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FRUIT p,-
NOTES

PREPARED BY
DEPARTMENT OF PLANT AND SOIL SCIENCES

COOPERATIVE EXTENSION SERVICE,
UNIVERSITY OF MASSACHUSETTS, UNITED
STATES DEPARTMENT OF AGRICULTURE AND
COUNTY EXTENSION SERVICES COOPERATING.

EDITORS
W. J. LORD AND W. J. BRAMLAGE

Vol. 48 No. 1
WINTER ISSUE, 1983

Table of Contents

FRUIT NOTES Subscription

Varieties of Grapes for Massachusetts

Varieties of Peaches for Massachusetts

Performance of Disease Resistant Apples
in Massachusetts

Disease Management for Apples in Massachusetts:
1982 Results and Summary of the Five-Year Program

Factors Affecting Nutrient Content of the Foliage
and Fruits of Apple Trees

Pomological Notes

Integrated Management of Apple Pests in Massachusetts,
1982 Results: Insects

Issued by the Cooperative Extension Service, Daniel I. Padberg, Director, in furtherance
of the Acts of May 8 and June 30, 1 91 4; United States Department of Agriculture and
County Extension Services cooperating. The Cooperative Extension Service offers equal
opportunity in programs and employment.

The cost of publishing FRUIT NOTES has become a significant
portion of the Smith-Lever allocation for my extension
program. If we continue to send it free- of - charge very
little money will be left for travel, attendance at meetings,
and supplies. Thus, starting with the Spring Issue, FRUIT
NOTES will be on a subscription basis at $3.00 per year for
4 issues. Hereafter, the subscription year will commence
with the Winter Issue. A notice for renewing your subscription
will appear in the fall issue of the previous year.

To subscribe to FRUIT NOTES, complete and mail the following
form with your check for $3.00.

William J. Lord
William J. Bramlage
Editors, FRUIT NOTES

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Mailing address

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Make checks payable to: FRUIT NOTES ACTIVITY ACCOUNT

Send subscription form and check to: William J. Lord

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French Hall

University of Massachusetts
Amherst, MA 01003

VARIETIES OF GRAPES FOR MASSACHUSETTS

James F. Anderson
Department of Plant and Soil Sciences

The following is a list of varieties that are currently
recommended for planting in Massachusetts. Many new seeded and
seedless varieties have been introduced in recent years. Some
of these may be equal to or better than the one listed. Those
growers interested in grapes for wine should obtain a copy of
the Catalog of New and Notev\forthy Fruits from the New York State
Fruit Testing Cooperative Association, Inc., Geneva, NY 14456.
This catalog offers a description of the French-hybrid and
other varieties suitable for wine production.

Variety

Recommended for

Harvest Season

Schuyler

Himrod

Van Buren

Ontario

Seneca

Suffolk Red

Fredonia

Buffalo

Delaware

Lakemont

Worden

Blue Boy (Cook)

Niagara

Concord

Steuben

T = Trial

H
C& H

T
C& H

H
C&H

T
C&H
C&H
C&H
C&H

H = Home garden

late-August

late August— early September

early September

mid-September

late-September

C = Commercial

All varieties are not necessarily equally adapted to all sections of the state. Late ripening varieties are recommended
only for those areas with a sufficiently long growing season to permit satisfactory ripening of the fruit.

Variety Notes

Schuyler — A very early, high-quality, black grape. The clusters are medium to large and moderately compact. The

berries are medium in size, tender, and juicy. The vine is vigorous, productive, and medium in hardiness.
Schuyler require severe pruning to prevent overbearing.

Himrod — An early-ripening, seedless grape resulting from a cross between Ontario and Thompson Seedless. Its

clusters are large and rather loose. The berries are medium, oval, sweet, yellow, vinous, and good. The
vine is not completely winter-hardy under our conditions and should be restricted to the more favored
sites.

Van Buren - An attractive, black grape of good to excellent quality. The vine is vigorous and productive. It is particu-
larly susceptible to downy mildew.

An early-ripening, white grape of high quality. The plust^rs are medium in size and tend to be loose. The
berries tend to shatter considerably within a few days after harvest. The vines are medium in vigor and
productivity, and are hardy.

An early-ripening, white grape with a thin, tender, adherent skin. The berries are medium in size, oval,
and have excellent flavor. The clusters are medium in size and compactness. Seneca is susceptible to win-
ter injury.
Suffolk Red - A bright-red, seedless grape. The clusters are medium in size and tend to be loose. The berries are medium
in size, round, and have very good quality. The vine is medium in hardiness.

Ontario —

Seneca

Fredonia — A good-quality, black grape especially recommended for the roadside stand trade. The clusters are com-

pact and medium in size. The vine is vigorous, hardy, and productive. It should be pruned less severely
than Concord.

Buffalo — A black grape with medium to large size, sweet, vinous flavor and good adherence. The clusters are large

and tend to be loose. The vine is vigorous and productive, and the fruit holds very well in storage. Buffalo
tends to overbear and to be susceptible to winter injury if not properly pruned.

Lakemont — A yellowish-green, seedless grape. Its clusters are medium to large and moderately compact. The berries
are medium to small in size, oval, tender, juicy, and sweet. The vine has moderate vigor and hardiness.
Tends to overbear.

Delaware — A high-quality, red grape with small clusters and berries. The vines are hardy and are moderate in vigor

and production. Delaware would add to the attractiveness of displays on a roadside stand.

Worden — Similar to Concord, but ripens a week to ten days earlier. While slightly superior to Concord in quality

and attractiveness, it has a tendency to crack when ripe and shatters badly within a few days after it is
harvested. A desirable variety for local trade and the home vineyard.

Blue Boy — This is an attractive, black grape with an abundance of bluish bloom. Adherence of the berries is good and
(Cook) the quality is excellent. Vines are productive and the fruit holds in storage unusually well. Recommended

for commercial planting and is a desirable variety for the home vineyard.

Niagara — A white grape of high quality with large compact clusters. Would add to attractiveness of display on a

roadside stand. Ripens with Concord.

Concord — The particular merits of Concord are its adaptability to a wide variety of soils, its productiveness, hardi-

ness, vigor, and shipping quality. Concord requires a growing season of approximately 160 days for
proper ripening of its crop.

Steuben — Those growers who can mature Concord might wish to try this variety. The grapes are bluish-black in

color, medium in size, and have very good quality. The clusters are medium to large, compact, and attrac-
tive. The vines are usually hardy, vigorous, and productive.

■A *********

Variety

■ A-

VAR urn lis 0|- PHACIIHS for MASSACimSr.TTS

.James F. Anderson
nepartmcnt of Plant and Soil Sciences

Recommended for

Flesh color

Approximate harvest date

Harbinger

Candor

Garnet Beauty

Sweethaven

Brighton

Harbelle

Reliance

Raritan Rose

Redhaven

Harken

Harbrite

Velvet

Jayhaven

Glohaven

Eden

Richhaven

Canadian Harmony

Cresthaven

Jerseyglo

Autumnglo

C — Commercial

C Y

T Y

C Y

T Y

T" Y

C Y

H Y

C W

C Y

T Y

C Y

T W

C Y

T Y

H — Home garden

-30
-20
-13
-13
-13

-8

-4

-2

+7
+10
+11
+12
+16
+21
+26
+30

T - Trial

All varieties are not necessarily equally adapted to all sections of the state.

2 V - Yellow flesh
W - White flesh

Based on harvest date for Redhaven (approximately August 20, but can vary from location to location and season
to season). Minus sign indicates number of days before; plus sign indicates number of days after Redhaven.

Harbinger —

Candor* —
Garnet Beauty —

Sweethaven* —

Variety Notes

An attractive, small to medium-sized clingstone peach. The flesh is yellow, firm, melting, and has
very good flavor for this season. The tree is vigorous, productive, and equal to Redhaven in bud
hardiness.

The fruits are well-colored, and small to medium in size. The flesh is yellow, firm, and juicy and
the stone is semi-cling. The buds are hardy and the tree vigorous and productive.

A bud-sport of Redhaven. Resembles Redhaven in color and texture. It is a semi-clingstone. The
tree is vigorous, productive, and hardy.

An early, yellow-fleshed, semi-clingstone peach. The fruits are medium in size, roundish, and well
colored. The flesh is juicy, slightly fibrous, but soft. The tree is vigorous, productive, and similar
to Redhaven in bud hardiness.

Brighton* —

Harbelle —

Reliance —
Raritan Rose —
Redhaven —
Harken —

Harbrite —
Velvet -
Jayhaven* —
Glohaven —

Eden* -

Richhaven —
Canadian Harmony
Cresthaven* —

Jerseyglo* —
Autumnglo* —

An attractive, high-quality, yellow-fleshed peach. The fruit is roundish, uniformly medium in
size, and highly colored. The flesh is medium firm, juicy, with very good flavor. The pit is semi-
cling. The tree is vigorous, productive, and medium-hardy.

The fruit is large, attractive, with deep-yellow ground color and a bright-red blush. Flesh is a rich
yellow, medium in firmness, of good quality. The stone is semi-free. The tree is productive, and
medium in vigor and bud hardiness.

A medium-sized, roundish, yellow-fleshed freestone peach of fair to good flavor. Reliance is
recommended as a very hardy variety for the home fruit planting.

The fruit is large, round, attractive. The flesh is white, firm and juicy. The tree is large, upright-
spreading, and productive. Bud hardiness is above average.

The medium-sized fruit is highly colored, attractive, and has firm flesh and fair flavor. The tree
is very productive and requires heavy thinning.

A large attractive, yellow-fleshed peach. The flesh is firm, juicy, of good quality and the stone is
free. The tree is vigorous, productive, and equal to Redhaven in bud hardiness.

A large, attractive, yellow-fleshed peach. The flesh is medium-firm, juicy, and of good flavor. The
stone is free. The tree is very productive, hardy and moderately vigorous.

A medium-to-large, attractive, freestone peach. The flesh is yellow, firm, juicy, and has very good
flavor. The tree is moderately bud hardy.

A medium-large, round, bright-colored freestone. The flesh is yellow and melting. The tree is
more bud hardy than Glohaven.

A large, roundish, mostly red peach with very little fuzz. The flesh is yellow, very firm, and has
very good flavor. The stone is free. The tree is medium in bud hardiness, but is vigorous and pro-
ductive.

The fruit is large, roundish, with 60 percent red on a creamy white ground color. The white
flesh is thick, firm, juicy, smooth, and very good in flavor. The stone is free. The tree is vigorous,
equal to Redhaven in bud hardiness, and very productive.

A large, attractive, highly-colored freestone of very good quality. The tree is large, vigorous,
and productive. Bud hardiness is above average.

A large, highly-colored, yellow-fleshed peach. The flesh is firm, juicy and of good flavor. The
tree is vigorous, productive, and about equal to Redhaven in bud hardiness.

A large, oblate-shaped peach with a dark-red blush. The bright yellow flesh is firm, juicy and
slightly fibrous. There is some red at the pit. The flavor is very good. The tree is vigorous, pro-
ductive, and medium in hardiness.

The fruits are large, attractive, and freestone. The flesh is yellow and firm. The trees are vigorous
and productive, and about equal to Redhaven in bud hardiness.

A large, round, highly-colored freestone. The flesh is yellow, firm, and melting. The trees are
vigorous, productive, and are equal to Redhaven in bud hardiness.

A A A ft A A A A A A

■6-

PERFORMANCE OF DISEASE RESISTANT APPLES IN MASSACHUSETTS

Christopher M. Beckerl Daniel R. Cooley,
and William J. Manning3

Department of Plant Pathology,
University of Massachusetts, Amherst

A number of apple cultivars, with immunity to apple scab, and varying
degrees of resistance to rusts, powdery mildew and fireblight, are currently
available from commercial nurseries. As these cultivars have potential use
in apple disease management programs, designed to reduce fungicide usage, we
established a block of disease resistant apple cultivars at the Horticultural
Research Center in the spring of 1978 to determine their performance in Mass-
achusetts. Fruit were harvested in 1982 for the first time.

Eight cultivars were planted. Prima, Priscilla, and Sir Prize were developed
by the Purdue, Rutgers, and Illinois (PRI) Agricultural Experiment Station co-
operative apple breeding program. MacFree and Nova Easy-gro were developed in
Canada and Liberty and NY61345-2 by the New York Agricultural Experiment
Station. Disease-susceptible Imperial Mcintosh was used for comparisons. Trees
were obtained from either the New York State Fruit Testing Cooperative or Stark
Bros. Nurseries.

Cultivars used have been described by their developers as follows:

Prima: 2-1/2 to 3". 60-80% bright red, over yellow ground color.

Rich flavor and crisp texture, with mild subacid flavor.
Flesh, light cream color. Little tendency for fruit to drop
before harvest. Fruit matures 1 month before Red Delicious,
and will retain its flavor for up to 1 month at 34 F. Trees
are spreading and vigorous. Immune to apple scab, susceptible
to cedar apple rust, slightly susceptible to powdery mildew,
and resistant to fire blight. Excellent dessert apple.

Priscilla : 2-1/2 to 3". 75-90% bright red, over yellow ground color..
Crisp texture and pleasant aromatic flavor. Texture and
flavor maintained for 2-3 months at 34 F. 2 weeks before
Delicious (10 days after Prima) . Little tendency for fruit
drop before harvest. Trees are moderately spreading and
vigorous: terminal growth frequently determinate, ending in
a flower bud. Trees and fruit are immune to apple scab,
and resistant to cedar apple rust, and fire blight. Fine
dessert quality.

Sir Prize : 3 to 3-1/2". Yellow, russet free. Ripens with Golden

Delicious (4 weeks after Prima). Juicy flesh, fine grained
texture with thin skir^ that is easily bruised with rough
handling. Waxy skin does not shrivel in storage. Very good
keeping quality through the winter season. Trees are vigorous,
triploid and produce an annual crop. Immune to apple scab,
moderately resistant to cedar apple rust and powdery mildew,
trees have shown little fire blight. Excellent for home
planting or use with direct sales or pick-your-own.

1 9

Disease Management Technician ^ Extension Technician

3 Professor of Plant Pathology

Macfree: 2-3/4", 75% medium to dark lively red, slightly stripped,

over greenish-yellow ground color. Juicy white flesh, sometimes
tinged with green. Slightly course, tough texture, moderate
acidity and firm; pleasant flavor. Ripens a few days before
Red Delicious, Stores 3 months at 32 C. Vigorous spreading
tree: fruit borne throughout. Resistant to apple scab.

Nova Easy-gro : 2-1/2", blushed or stripped medium red over pale greenish-
yellow ground color. Creamy white flesh, firm, crisp, moderately
juicy, subacid; pleasant. Matures with Cortland, keeps well.
Trees are moderately vigorous, and spreading, with fruit borne
throughout the tree. Fruit resistant to apple scab. (Multigenic
resistance from Russian seedling) .

Liberty : 2-3/4", deep bright red, stripped on greenish-yellow ground
color. (Mcintosh parentage easily recognizable.) Flesh pale
yellow, nearly white; crisp, juicy, slightly coarse in texture.
"Sprightly", subacid; browns rapidly upon exposure to air.
Keeps well under refridgeration until January and stores very
well as juice, cider and sauce. Trees are "precocious"; out-
yielded Mcintosh and Red Delicious on similar topworked trees.
Vigorous growth, round topped and spreading: very productive
with fruitbuds terminally and laterally on shoots of current
year's growth and spurs. Immune to apple scab and cedar apple
rust; resistant to powdery mildew and fire blight.

NY 61345-2 : 2-7/8", 90% red blush. Crisp, juicy, slightly coarse; sprightly.
Tree: vigorous and upright. 2 days before Red Delicious. Immune
to apple scab, moderately resistant to cedar apple rust and
powdery mildew.

Standard insecticide sprays were applied from 1978-1982, but no fungicides
were used. Natural inoculum for apple scab and cedar-apple rust was abundant
in all years.

In mid-September, 100 randomly-chosen leaves per tree were evaluated for
per cent apple scab, cedar-apple rust, and frog-eye leaf spot (black rot). Fruit
were evaluated at harvest for scab and other diseases. Results are summarized
in Table 1.

All of the disease resistant cultivars were completely free from fruit
and foliar scab. Imperial Mcintosh, however, had 48.5% foliar and 28.3% fruit
scab. While all the disease resistant cultivars had less foliar cedar-apple
rust than Imperial Mcintosh, Macfree and Sir Prize had more foliar infection
than Nova Easy-gro, NY 61345-1, Priscilla, and Liberty. The original Prima
trees died before 1982. Several younger Prima trees were completely free from
scab, but had extensive cedar-apple rust on leaves. One Prima fruit also had
a rust infection spot. All cultivars had frog-eye leaf spot, with Sir Prize
having the highest incidence. Frog-eye leaf spot on Sir Prize, however, consists
primarily of small purplish flecks, rather than more typical symptoms.

To determine fruit quality. Nova Easy-gro, Liberty, Macfree, NY 61345-2, and
Imperial Mcintosh fruit were harvested and stored at 34 F. in a conventional
cold storage. After one month of storage, fruit were removed, sliced, and
offered to 29 randomly-chosen students, secretaries, faculty and technicians.

Most tasters found little difference between Imperial Mcintosh, Macfree, and
Nova Easy-gro. While all had similar textures Nova Easy-gro, and Macfree were
judged to have slightly less flavor than Imperial Mcintosh. Wi 61345-2 was
generally agreed to be a tasty and slightly tart apple. While not as firm as
Imperial Mcintosh, NY 61345-2 was rated as the first choice of most tasters.
Liberty compared well with Imperial Mcintosh, but was not as sweet and did
not store as well.

When tasters were shown nonlabelled fruit of all the cultivars, all comments
were favorable. More than 80% of the tasters agreed that they would purchase
the fruit if available in roadside stands or in supermarkets.

In 1983, we will be adding the following new cultivars to our planting:

Redfree: Redfree is a medium size (2-3/4") apple with 90% good red

color and smooth, waxy, russet-free skin. Flesh is white,
crisp and juicy. Retains quality for two months or more in
storage. Fruit ripens 3 weeks before Prima and 7 weeks before
Delicious. Immune to scab and cedar rust, moderately resistant
to fire blight and mildew.

Jonaf ree: Closely resembles and matures with Jonathan. Fruits are
2-1/2 to 2-3/4", 75% medium red, with a smooth russet-free
skin. Flesh is pale, crisp, and juicy. Immune to scab and
resistant to fire blight and cedar-apple rust. Moderately
susceptible to mildew. Fruit hangs well to maturity and do
not develop Jonathan spot.

King Luscious : A very large, highly-colored apple with good keeping, eating
and cooking qualities. The skin is a deep red with a beautiful
bloom. The flesh is pure white, with excellent flavor. Season
of ripening is with Rome Beauty and Stayman, although it may
be picked sooner for cooking purposes. The tree is a young
and annual bearer, blooming a week after Rome Beauty, to
make it almost completely frost-proof. The tree is semi-
dwarf in habit, sets it scaffold branches well, and needs
little pruning. Both tree and fruit are resistant to apple
scab. U.S. Plant Patent No, 1994.

Redfree and Jonaf ree are being obtained from Hilltop Nurseries. King
Luscious will come from Bountiful Ridge Nurseries.

All of the trees in the Disease Resistance block will be labelled this
spring by name. Please feel free to examine them when you visit the Horticultural
Research Center. For additional information on disease resistant apple trees,
contact Dr. William J. Manning in the Department of Plant Pathology.

This activity is supported by the Massachusetts Cooperative Extension Service.

Table 1. Performance of young disease resistant apple trees in Massachusetts
in 1982.

% foliar disease

No.

(100

leaves

evaluated/ tree)

trees

Cultivars

Scab

Rust

Frog-eye

fruit

% Scab

Macfree

■

18.5

22.5

Nova Easy-gro

0.5

15.5

NY 61345-2

0.5

23.3

Priscilla

4.0

15.0

Sir Prize

32.0

75.5

Liberty

1.3

11.3

Imp. Mcintosh

48.5

44.0

20.0

26.3

-10-

DISEASE MANAGE^fENT FOR APPLES IN MASSACHUSETTS:
1982 RESULTS AND SUMMARY OF THE FIVE-YEAR PROGRAM

Christopher M. Becker,^ Ted R. Bardinelli,2
Daniel R. Cooley,^ Kristin G. Pategas,^and
William J. Manning^

Department of Plant Pathology
University of Massachusetts, Amherst

The five-year pilot program to develop and evaluate new and innovative
apple disease management practices in Massachusetts terminated in 1982. Our
results for 1982 and a summary of the entire program are presented here.

1982 Results

In 1982, 13 commercial apple orchards were involved in the program. Four
followed traditional disease management practices and served as controls for
comparisons. The other 9 were visited by scouts on a regular basis and ap-
plied fungicides to manage apple scab (and other diseases) on a "post-infection"
basis only. Hygro thermographs were used to determine when infection periods
had occurred and when fungicides should be applied. A more complete descrip-
tion of the disease management program can be found in Fruit Notes 46(1) pp. 3-4.

Like many growing seasons in Massachusetts, 1982 was unusual. New green
apple leaves emerged at the same time that mature ascospores of the scab fungus
were available. Two extensive Infection periods occurred in late May with heavy
inoculum released. Primary scab season ended on 4th June. A complete summary
of wetting and infection periods for 1982 is given in Table 1.

Fungicide usage and fruit disease incidence for disease management orch-
ards are given in Table 2. Results for control orchards are In Table 3.
Disease management orchards averaged one less fungicide application. Reduc-
tion in dosage equivalents (2.6 fewer than controls), however, resulted in
savings of $32 per acre for fungicides. Disease management orchards had a
slight increase in per cent diseased fruit at harvest when compared to con-
trols. Savings realized with reduced fungicide costs, however, more than
offset the slight increase in costs due to a few more diseased fruit at
harvest.

Paired t-tests were used to compare results from disease management and
control orchards (Table 4). No significant differences (P = 0.05) were found
between the number of fungicide applications, per cent diseased fruit at har-
vest, and dollar losses from disease. There was a significant difference
between actual fungicide usage, or dosage equivalents, and fungicide costs
per acre. Disease management growers used less fungicide without significant
increases in fruit diseases at harvest.

Variation in the number of fungicide sprays (8-14) and dosage equivalents
(5.67-11.88) in IPM orchards is closely related with both efficiency in timing
of scab sprays, and the necessity for fungicide applications for diseases other
than apple scab, especially the rusts, and powdery mildew. When post- infec-
tion scab sprays were too late to Inhibit apple scab infections, or poor cover-
age was achieved by spraying during windy weather, additional fungicide appli-

llPM Technician 1981-82 ^IFH Technician 1978-80 3Extension Technician
^IPM Scout ^Professor of Plant Pathology

-11-

cations at high rates were necessary to "burn-out" or eradicate scab lesions.
Where rust control was essential, protective sprays were necessary before
all wetting periods (over 4 hours in length) as post-infection applications
of fungicides are not possible for rust management.

Five- Year Summary

A cost/benefit analysis for the five-year program is presented in Table
A. In each year of the program, disease management growers made fewer fungi-
cide applications, with fewer dosage equivalents, and reduced fungicide costs,
compared to control growers. Per cent diseased fruit at harvest in disease
management orchards was either comparable to or only slightly higher than in
control orchards. Disease management benefits per acre were variable, but
always positive for cooperating growers.

When we examined the results for a five-year period, three trends became
evident to us. The first was that disease management benefits are most likely
to occur at a higher dollar level in dry spring seasons, as in 1980, rather
than in wet ones, as in 1982. With fewer wetting periods, greater efficiency
can be achieved in timing post-infection sprays.

The second trend is that continued benefits from disease management de-
crease in magnitude with time. Fungicide sprays and dosage equivalents can-
not be further reduced in number every year. Many control growers have also
begun to adopt disease management practices, obtained from the numerous Ex-
tension education programs we have been involved in over the past five years.
It is becoming increasingly difficult to find control orchards where only
traditional methods are used.

Per cent disease incidence for the five-year period is summarized in
Table 5. Apple scab incidence has been reduced. The trend for calyx end
rots, however, is increasing slightly. Timing sprays only for scab manage-
ment may have increased infection possibilities for end rot fungi before
or after bloom. Using fungicides that are good for scab management may also
mean that they are not as good for end rot management. Anytime a practice
is changed, we can expect that new problems may develop. The use of one or
more sprays of a protective fungicide, rather than a "post-infection" or
"kick-back" material, from tight cluster to petal fall, should eliminate
calyx end rot problems, especially during wet growing seasons.

Acknowledgements :

We have been able to obtain considerable information about apple disease
management during the last five years. We could not have done this without
the enthusiastic and generous support and cooperation of the participating
Massachusetts fruit growers.

This program was supported by special funds from the USDA, by the Massa-
chusetts Cooperative Extension Service, and the Massachusetts Fruit Growers
Association.

12-

Table 1. Wetting and infection periods for the apple scab fungus at the Horticultural
Research Center in Belchertown, MA in 1982

Apple
growth

Wetting Periods

Rain

% Mature
apple scab

Potential

Hour

Duration Mean Temp.

primary-

Date

stage

began

(hrs . )

CF)

(mm)

ascospores

scab infec-

tion

severity

A/17/82

Green tip

17.2

None

4/21/82

Green tip

4.5

None

4/24/82

1" green

0.01

None

4/26/82

1" green

23.5

Heavy

4/27/82

Tight cluster

4.6

None

5/8/82

Early bloom

0.7

None

5/19/82

Petal fall

7.8

None

5/22/82

Petal fall

16.1

Heavy

5/29/82

Late petal

fall

70.8

Heavy

5/30/82

1/4" fruit

0.5

Moderate

6/1/82

1/4" fruit

24.5

Moderate

*6/4/82

1/4" fruit

93.2

Heavy

*End of primary scab season.

Table 2. Cost/benefit analysis of fungicide usage and fruit quality in disease
management orchards in 1982

Orchard

% Diseased
fruits at
harvest

$ Loss to
disease per
acre

Number of
fungicide
sprays

Dosage
equivalents

Fungicide
cost per
acre

0,1 scab

0.1 end rot

7.70

8.26

$ 81.75

0.1 scab
0.1 black rot
1.1 end rot
1.1 quince rust

92.40

11.76

$122.72

0.1 scab

0.2 quince rust

1.8 end rot

80.85

10.2

$100.40

0.3 scab
0.1 quince rust
2.3 end rot
0.1 black rot

107.80

11.88

$113.46

0.2 scab

7.70

10.32

$121.28

0.1 scab
0.1 quince rust
0.1 bitter rot
2.8 end rot

119.35

8.80

$ 95.01

0.1 scab

19.25

8.48

$ 97.14

0.4 end rot

15.40

9.44

$122.31

0.1 end rot

3.85

5.67

$ 66.18

Avg.

0.11 scab
1.00 end rot
0.16 quince rust
0.04 other

1.31 TOTAL

50.48

11.20

9.42

$102.25

Table 3. Cost/benefit analysis of fungicide usage and fruit quality in control
orchards in 1982

% Diseased

$ Loss to

Number of

Dosage

Fungicide

Orchard

fruits at

disease per

f ungic ide

equivalents

cost per

harvest

acre

sprays

acre

13.64

$149.10

0.10 scab

3.85

11.64

$133.44

0.60 scab

0.30 end rot

77.00

9.81

$106.38

0.10 black rot

13.0

$148.29

Average . 53

20.21

12.5

12.02

$134.30

15-

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-16-

Table 5. Per cent disease incidence at harvest in apples from disease
management orchards in Massachusetts for a five-year period

Disease 1978 1979 1980 1981 1982

Apple scab
Calyx end rots
Rusts
Black rot
Bitter rot
Fly speck
Other*

Total 3.45 0.99 0.90 0.77 1.31

*0ther includes sooty blotch, moldy core and white rot.

2.88

0.66

0.46

0.13

0.11

0.08

0.19

0.14

1.00

0.06

0.07

0.03

0.17

0.44

0.07

0.08

0.02

0.05

0.02

0.04

0.01

0.06

0.04

0.05

0.01

0.05

0.37

-17-

FACTORS AFFECTING NUTRIENT CONTENT OF THE FOLIAGE
AND FRUITS OF APPLE TREES

William J. Lord and William J. Bramlage
Department of Plant and Soil Sciences

Ideas as to what constitutes a desirable fertilizer program
have changed several times during the last 80 years. At one
time it was thought that orchards needed only phosphorous (P)
and potassium (K) containing fertilizers. Very little, if any,
nitrogen (N) was recommended. The use of N, only, was the next
concept for meeting the nutrient need of trees. By 1950 annual
applications of N and occasional applications of K, magnesium
(Mg) and boron (B) were being recommended in Massachusetts. Witli
the exception of N, Mg was considered the element most likely
to be deficient in our orchard soils. P was not considered a
limiting factor in orchard soils and there was no evidence that
apple trees suffered from lack of calcium (Ca) .

In the mid-1950's, Weeks et al . in Massachusetts reported
that Mcintosh trees with a medium level of leaf N and a high level
of leaf K produced fruit with more red color than those with high
or medium N and low K, and growers were advised to use less N
and more K. By this time the detrimental effects of high N on
pre-harvest drop, flesh firmness and storage life of fruits was
well recognized. Leaf analysis now was considered a more useful
diagnostic tool than soil analysis for determining the nutritional
needs of apple trees.

During the last 2 decades even greater attention has been
given to the effects of nutrition on the quality of harvested
fruits. Calcium deficiency was found associated with some physio-
logical disorders of apples. These findings have continued to
stimulate considerable research emphasis on the roles of both
macro- and micro-elements in the postharvest quality of fruits.
An area of particular interest in England and Massachusetts is
determining the usefulness of fruit analysis for predicting
storage life. Hence, it is obvious that the scope of apple nutri-
tion has widened from theconcern about the tree to achieving
optimum nutrition for both the tree and the fruit. Unfortunately,
the needs of the tree and fruit may differ and a compromise is
necessary in some instances. Here we review the factors affect-
ing the nutrient content of the trees and fruit, and the relation-
ship between nutrition and fruit quality.

Crop Size

The effects of crop size on vegetative growth, nutrient uptake,
and leaf and fruit nutrition are shown in Table 1.

-18-

Table 1. The effects of cropping on growth, and leaf and fruit
nutrition of apple trees.

Measure

Heavy cropping trees in comparison to
non-bearing or light - cropping trees
will have:

Vegetative growth
Nutrient uptake

Leaf N
Fruit N

Leaf K
Fruit K

Leaf Ca
Fruit Ca
Leaf Mg
Fruit Mg
Leaf P
Fruit P

Less shoot and root growth .

Less uptake of elements because of
restriction oi' root growth.

Higher leaf N

No effect but if fruit N too high
quality will be reduced.

Lower leaf K

Lower fruit K because of large demand
of fruits for this element

High leaf Ca

Higher fruit Ca

Slightly higher leaf Mg

Little, if any, effect

Leaves from a large crop tree may contain 0.2 to 0.3-0 more N
than when the same tree has a light crop. K in leaves may decline
as much as 0.4% in a heavy crop year. Leaf Ca follows the same
trend as N and exhibits about the same difference as N in leaf
content between the light and heavy crop years. Leaf Mg is slightly
higher in a heavy crop than in a light crop year. Crop size has
little, if any, effect on leaf P.

Total K absorbed and the total dry matter produced is similar
for fruiting and non-fruiting trees but in heavy-cropping trees
is translocated into the fruits. Thus, the demand of a large crop
for K is great and both the tree and fruit may be deficient in
this element. Leaf injury because of K deficiency can cause pre-
harvest drop and reduce fruit size. In contrast, light cropping
trees are probably much higher in K than is needed because of
"luxury" uptake.

-19-

A very small amount of Ca moves into the fruits in compari-
son to the amounts of Mg , N, P and K. Nevertheless the presence
of adequate Ca in the soil does not assure sufficient uptake by
the tree and translocation especially to the fruit; nor does
adequate Ca in the tree ensure optimum Ca levels in the fruit
because there is competition between leaves and fruits for this
clement and leaves are a stronger competitor. The high leaf/fruit
ratio on light cropping trees tends to increase fruit size which
dilutes the Ca content of the fruit. In contrast, heavy cropping
reduces the excessive vegetative demand for Ca and makes this
element more available to the fruit. Fruit size may be reduced
by heavy cropping; smaller fruit have more Ca than larger fruit.

Fruits which constitute the greater part of the total dry
matter iii fruiting trees, have a much lower N concentration in
their dry matter than is found in the new growth of non-fruiting
or light- fruit ing trees. Therefore, N deficiency is most likely
to occur on non- or light - fruiting trees which have large demand
for this element for root and top growth, than on a heavy- cropping
tree. Mg tends to accumulate at a uniform rate in the fruit and
any reduction in Ca accumulation is reflected by a higher ratio
of Mg and/or K to Ca .

It is clear from above that the nutrient needs differ greatly
for the non- or light-cropping tree in comparison to the heavy-
cropping tree. Except for uptake of K, which is very mobile, the
uptake and transport of nutrients is suppressed by heavy fruiting.
Also with the exception of K the demands for the other nutrients
is much less in heavily bearing trees in comparison to those
with no crop or a light crop. What does this mean in regard to
fertilization?

Young non-bearing trees require heavy fertilization with N
to stimulate growth and only moderate amounts of K, and P is not
considered a limiting factor in orchard soils. N levels should be
reduced in bearing trees (1.80 - 2.00% "leaf N is optimum for most
varieties) and moderate levels of K, Mg , B and high levels of
Ca should be maintained. Unfortunately, sufficiently high levels
of Ca generally are possible only by spray applications of CaCl^.
And, as discussed later, soil management practices may have greater
influence on tree nutrition than fertilization.

Interaction Among Elements

Ca deficiency can occur independently of its availability in
the soil because excess K can affect uptake, and after uptake the
distribution within the tree. Thus, the Ca/K ratio may be as
important as the availability of the Ca. Researchers in South Africa
believe that leaf Ca level of 1.60% and a K/Ca ratio of 0.65 are
necessary to minimize the incidence of bitter pit under their
conditions .

20-

An excess of N increases the need for Ca. In young leaves
of rapidly j^rowing shoots most of the Ca may be tied up in the
form of calcium oxalate and the supply of this element may tlius
be low for other functions.

Leaf Mg is apt to be suppressed by high leaf K but in fruits
there is a positive correlation between K and Mg , showing that an
increase in one element is accompanied by an increase in the otlicr.
At Ca levels below a certain threshold value, Mg may substitute
for Ca . However, increasing Mg from a deficient to an adequate
level can actually increase Ca uptake because breakdown of the feeder
root system, essential foi- nutrient uptake, is the first effect of Mg
de f iciency .

Roots and Soil

The growth and function of the roots are closely linked to
those of the shoot. The roots are dependent on the shoots for
assimilation whereas roots produce hormones and remove from the soil
elements essential for shoot activity. An important factor re-
stricting root development is the aeration status of the soil.
Roots of fruit trees will avoid regions of poor aeration. Thus,
on soils with a high water table, the trees will be shallow rooted.
Nutrient uptake may be sufficient on these soils, however, shallow-
rooted trees will suffer from drought sooner than those with deep
roots. A drought will lower the availability of nutrients to the
roots, restrict root growth, and may decrease the absorptive
capacity of the roots quite markedly.

Far more insidious conditions occur in soils subject to tempor-
ary water logging because of the presence of a hardpan near the soil
surface. This occurs on a Wethersfield soil at the Horticultural
Research Center where trees will become severely weakened or die
for lack of soil oxygen because of temporary water saturation within
20 inches of the soil surface in the spring.

Not all horizons in the soil are equally able to supply nutrients
to the tree. The concentrations of most elements are highest at
the soil surface and decrease with depth, but the rate of decrease
differs between elements. For example, there is a strong vertical
difference in K status in soil, K being highest near the surface.

Under drought conditions the permeability of the roots to water
uptake decreases very rapidly; reduction in water permeability
reduces the uptake of all ions. In Massachusetts we arc particularly
concerned about K and B deficiency and reduced fruit size in drought
years .

21-

Soil Management

Soil-mulch systems . When apple trees are heavily mulched, it is
necessary to adjust fertilizer programs, especially aTter the
mulch commenced to decay. While the material applied as mulch
varies considerably in chemical content, the average hay mulch
contains approximately 1% N, 0.41 P, and 1.3% K. On this basis,
33 pounds of hay mulch is equivalent to 1 pound of ammonium
nitrate in respect to the N added to the soil. The heavy appli-
cation of mulch eventually adds large quantities of K and N to
the soil. In addition to adding K to the soil, mulch makes more
readily available the soil's reserve supply of K.

Mulching presents a dilemma in regards to nutrition. Hay
mulch can suppress grass and weed growth, improve soil structure,
conserve moisture, and is a source of N and K. Calcium mobility
might be greater under mulched trees becaus'e this element is
carried by water. High K is favorable for red color development
and the need of this element is high in heavy- cropping trees.
In contrast, high K can suppress Ca uptake and mulch might pro-
vide excessive N.

Cult ivation . This system of soil management is generally practiced
only in young plantings when land has been cleared from woods
or when an old orchard site is renovated. After a year or 2,
grasses and weeds are allowed to re-establish themselves between
the rows or the land is re- seeded.

Cultivation under the trees can affect nutrient level because
it destroys the roots in the surface soil which is particularly
high in K and P. Grass and weed competition are reduced by
cultivation, thus soil moisture is conserved and N is more avail-
able because grass competes with the trees for N.

Chemical Weed Control . Considerable attention has been given to
the effect of herbicides on nutrition. A number of workers have
reported that sub-lethal concentrations of simazine will increase
leaf N of apple trees. In contrast, in our field studies, no
differences in nutrient levels or in growth of apple trees could
be attributed to simazine. However, in greenhouse studies, we
found th'at low concentrations of soi 1 - incorporated simazine did
increase leaf N of Mcintosh apple trees grown in 30 lb. cans. We
believe the lack of a response under our field conditions is
because most of the simazine is adsorbed by the organic matter in
the upper 3 inches of the soil and not available to tree roots.

The effects of herbicide strips on root growth and nutrient
uptake have recently received much attention in England and Europe
The studies at East Mailing Research Station show that apple trees
produce most of their roots in and obtain most of their mineral
nutrients from the soil of the herbicide strip. Root growth under

22-

the grassed alley appeai'ed deeper and more sparse.

Herbicides indirectly affect the nutrition of fruit trees
because killing of vegetation under the trees reduces the com-
petition between the grass and tree roots for minerals and
water. Furthermore, herbicides will decrease soil pH and ad-
versely affect earthworm populations and thereby soil structure.

Effects of Fertilization on Fruit Quality

Calcium : In 1936 bitter pit was found to be related to low Ca
levels in apples. Thirty years later it could still be stated
that "Inspite of the very low Ca status of many orchards soils.,
there have been few reports of direct responses by bearing apple
trees to Ca . . . " ( Temperate to Tropical Fruit Nutrition , Norman
F. Childers, Editor) . Today , however , there is strong concern
about Ca levels in apples and pears just about anywhere in the
world that they are grown .

At first, this concern was directed at bitter pit and cork
spot but today we know that many physiological disorders may be
at least partly related to low Ca levels in the fruit. In Vv-armer
fruit growing areas, cork spot and bitter pit remain the most
serious effects of low Ca, but in cooler areas various forms of
internal breakdown are the most serious Ca-def iciency problem.
In British Columbia, Canada, the 'Spartan' apple industry was
almost destroyed by breakdown problems before methods of raising
fruit Ca levels were successfully developed.

Nitrogen : Excessive amount of N in the tree and fruit can severely
reduce fruit quality. The vigorous growth that it encourages
reduces the Ca level of the fruit. Moreover, the high N fruit
tend to be larger, greener, softer, more subject to preharvest
drop, and to have more cork spot and bitter pit. These fruit
also tend to develop greater amounts of scald, bitter pit, inter-
nal browning, and internal breakdown during and after storage.

Excessive N levels are probably very common but deficient
levels rarely occur. In the Pacific Northwest it has been esti-
mated that 50 to 751 of apple orchards and a smaller percentage
of pear orchards, are excessively high in N. The effects of high
N on apples are perhaps being masked at harvest by use of growth
regulators, especially Alar, but growth regulators cannot mask
their consequences after storage.

Potassium : K deficiency has only a mild effect on fruit quality,
reducing acidity of the fruit and reducing red coloration. Ex-
cessive amounts of K in fruit are a greater danger to fruit quality,
since they lead to increased scald, bitter pit, and internal break-
down after storage.

-23-

Magnesi um : There is little evidence that either too little
or too much Mg directly affects fruit quality. However, excess
Mg interferes with Ca just as does excess K, so excessive amounts
of Mg will produce Ca deficiency effects in fruit.

Phosphorus : P deficiency can reduce tree growth and yield, and
in several parts of the world it has also been shown to cause
increased amounts of breakdown of apples during storage. How-
ever, in North America there has been very little evidence f6r
P deficiency in fruit. We have recently found that high levels
of P in apples, especially in combination with low levels of
Ca, greatly increased breakdown of apples during storage.

Boron : B deficiency has occurred over much of North America,
causing both internal and external cork development in fruit.
Excessive levels of B in fruit can cause earlier maturation and
increased amounts of water core at harvest, and increased amounts
of breakdown after storage. Thus, a moderate level of B is
important for good fruit quality.

B also influences Ca movement in the tree. If it is deficient,
less Ca is moved to the fruit and Ca deficiency can result. It
is therefore important to maintain adequate B levels as a part of
a program to avoid Ca deficiency.

POMOLOGICAL NOTES

For Those Who Care To Know . The first mimeographed copies of
FRUIT NOTES was issued in March, 1936 with Bill Thies, Editor, at
about the time of the spring flood. (The spring flood of 1936 is
well remembered by some of us older folks.) With an exception
of a few months when no issue was prepared, it has appeared at
regular intervals from 1936 to the present time. William Lord be-
came Editor in 1955 and William Bramlage, Co-editor, in 1966. We
have a mailing list of approximately 1600 and it is mailed to
19 foreign countries.

W . M .

INTEGRATED MANAGEMENT OF APPLE PESTS IN MASSACHUSETTS,
1982 RESULTS: INSECTS

Coli , R. Zahnleuter , D. Gordon , K. Leahy , J. Parella ,
D. Roberts and R.J. Prokopy

Summary of Results.

In 1982, 36 IPM blocks received 11% fewer insect-
icide and 171 fewer miticide but 201 more aphicide
dosage equivalents than check blocks. Insect
injury to fruit at harvest in IPM blocks averaged
4.2-0, versus 3.5% in the checks. Growers completely
implementing IPM specialist recommendations (100%
cooperator blocks) realized a net benefit of $56.95
per acre from IPM.

Number of orchard blocks scouted .

In 1982, each week from April 12 to September 15, field
staff visited 36 IPM blocks (about 400 acres) in 20 commercial
orchards throughout the state. Growers received a written scouting
report and were contacted in person or by telephone by the IPM
specialist regarding the need for spraying, recommended materials,
rates and timing.

Four commercial check blocks were monitored for presence of
aphids and mites and their predators 2 or 3 times during the season.
In addition, on-tree harvest surveys and comparisons of spray records
were performed in 7 commercial check orchards.

Grower financial support .

All participating IPM growers were charged $20 per scouted acre
for insect and mite scouting and advising. A minimum charge of $400
was instituted for growers v^ho wished to be on the program but who
signed up less than 20 acres. The charge for disease scouting,
weather monitoring stations and grower advising was $200 per orchard
in 1982.

Pest Management Specialist
2
Senior Field Scout

Field Scout
4
Extension Entomologist

Reduced spray programs on apples have been discussed in previous
issues of Fruit Notes : 41(1), 41(2), 41(3), and 43(3) , and our
1978, 44(6) , 45(6) and 47(1).

Total grower contribution to the IPM program was $9,500 in

1982, up from $8,500 in 1981. This money was placed in an Extension

Activity Account earmarked for Apple IPM program uses (scout sala-
ries , etc . ) .

We would like to extend special thanks to Mr. David Chandler,
Meadowbrook Orchards for his generous donation of a 1975 Buick sta-
tion wagon for IPM use. The addition of this fine vehicle should
enable us to extend the useful life of other IPM vehicles previously
donated by the Massachusetts Fruit Growers Association.

The extent of grower financial support of the Apple IPM pro-
gram has been commendable and will serve as a standard by which to
gauge levels of support of new IPM projects serving other commodity
groups in the state.

On behalf of all IPM program staff past and present, we wish to
express our sincere appreciation for the support and cooperation our
pilot program has received.

Sampling methods .

We have discussed our monitoring techniques in previous issues
of Fruit Notes . One major addition to these techniques was continued
field testing of a visual trap for Tentiform leafminer. As we report-
ed in 1981, preliminary results are encouraging. These results will
be discussed in a later issue of Fruit Notes .

Degree of cooperation with IPM specialist advising .

The extent of grower cooperation with specialist spray recommend-
ations was excellent in 1982, averaging 831 cooperation (range 43 -
100%). While this is somewhat lower than last year when cooperation
averaged 891, in 1981 only 11% of IPM blocks (4 36 blocks) com-
pletely followed specialist advising, but in 1982, 42% of IPM blocks
(15 out of 36) completely implemented specialist recommendations.

Such blocks had substantially lower harvest injury in spite of
fewer insecticide spray applications when compared to all partial co-
operator IPM blocks (Table 1).

Table 1. Percent insect injury and number of insecticide dosage

equivalents (DE) in 1001 vs. partial cooperator IPM blocks, 1982.

Previous Year
All IPM Blocks IPM Blocks only

% Insect
Injury

Insecticide
DE

No.
Blocks

% Insect
Inj viry

Insecticide
DE

No.
Blocks

100%
Cooperators

Partial
Cooperators

3.4
4.7

4.9
6.2

15
21

2.8
5.6

4.6

6.4

12
12

RESULTS ^^

New or unusual occurrences .

Some blocks again experienced a problem with gypsy moths (GM)
blowing in during bloom. Very little fruit injury resulted from GM
feeding this year, however, and control with petal fall sprays was
excellent. Few growers experienced problems with large, late instar
larvae migrating from adjacent defoliated oak stands in 1982.

Spotted tentiform and apple blotch leafminers (STLM/ABLM) were
,.^11 below treatment levels in many IPM blocks where 1981 mine counts
had been high. Although some IPM groivers used Vydate* (oxamyl) at
pink, others who elected to wait for results of mine counts were
able to withhold leafminer treatments for the entire season without
the harmful polulation increases that occurred in past years.

The reasons for this drop in leafminer pressure are unclear,
and our present knowledge does not allow us to predict the potential
for leafminer problems in 1983.

Both syrphid fly and cecidomyiid midge aphid predators were
abundant in IPM blocks in 1982 (Table 3). In spite of this, honey-
dew accumulation was extensive enough to warrant aphicide sprays in
10 such blocks.

Fruit injury .

Fruit injury at harvest in Previous -year IPM, First-year IPM
and check blocks averaged 4.3, 3.8 and 3.5%, respectively (Table 2).
The somewhat higher injury level in Previous -year blocks was due
largely to sooty mold fungus growing on aphid honeydew observed on
21% of sampled fruit in one IPM block.

This injury resulted from a late season (August) infestation
of green aphids on watersprout regrowth in the top center of tree
canopies. It is doubtful that such injury is of economic signifi-
cance in this case, however, as the grower typically wipes and pol-
ishes fruit prior to display in the apple sales room at the farm
and should be able to remove most of this injury.

Of insects causing non-removable injury, San Jose Scale (SJS)
was most troublesome and difficult to control in many commercial
block samples (Table 2) . For the first time in recent memory av-
erage injury from SJS surpassed that of the tarnished plant bug,
(TPB) normally the single most injurious apple pest in Massachusetts.

Lack of adequate SJS control can be attributed to several fac-
tors. These include: (a) reduced usage of semidormant oil sprays;
(b) frequent and heavy rain showers when treatment was required for
1st generation SJS crawlers; (c) grower reliance on concentrate
sprays (30-50 gals, per acre) on large trees in hot, dry weather
when treating for 2nd generation crawlers; and (d) substantially
reduced use of microencapsulated methylparathion (Penncap-M*) in

Trade Name

response to pesticide board regulations governing its use.

In one block with a long history of SJS problems, Diazinon*pro-
vided excellent SJS control in combination with an aggressive oil
program, pruning to enhance spray penetration, and frequent grower
scouting. This program resulted in 01 SJS injury in 1982 compared
to 91 such injury in the block in 1980.

European apple sawfly (EAS) injury was substantially higher in
all blocks checked in 1982 than in previous years (Table 2). This
finding, also observed by IPM personnel in Vermont, may have been
due largely to higher EAS populations in several blocks (cumulative
average of 43 EAS per trap in one case, 27 per trap in another, for
example) .

This apparently higher than normal EAS injury may also be re-
lated to our continued efforts to distinguish between TPB "dimples"
and EAS "stings" which are similar in appearance. Inasmuch as most
EAS injury in 1982 consisted of "stings" rather than well developed
larval burrows, most EAS injury was not of economic significance.

Tarnished plant bug injury was somewhat lower in 1982 than in
recent years. As we have noted previously and as researchers in
New York State have recently confirmed, the majority of TPB injury
consists of "dimples" in the fruit calyx which will not adversely
affect fruit grade.

In 1982, based on use of white TPB traps, 21% of IPM blocks
were able to withhold pre-bloom TPB sprays while sustaining 1.1%
injury from this pest, compared to 0.83% injury in the sprayed
checks .

Plum curculio (PC) injury was lower on average in all blocks in
1982, accounting for 0.43, 0.37 and 0.26% average injury in Previous-
year IPM, First-year IPM and checks, respectively (Table 2).

Much of the observed PC injury occurred in late June with an
unexpected burst of PC activity and most injury was confined to
block peripheries. Several blocks achieved good PC control using
border sprays subsequent to an initial block-wide PC treatment ap-
plied in response to first observation of this pest's activity in
commercial blocks.

Combined injury from Gypsy moth, Apple maggot fly (AMP), Leaf-
rollers (LR) , Codling moth (CM), White apple leafhopper (WAL) and
Green fruitworms (GFW) was low in 1982, accounting for a total of
0.04, 0.12, and 0.09% injury in Previous -year IPM, First-year IPM
and check blocks, respectively.

Private scout/consultants (New England Fruit Consultants)
report a possible case of resistance in Green Fruitworm to organo-
phosphate insecticides. Such resistance in GFW has been noted in
the Hudson Valley of New York and points out the need for continued
monitoring of pests which are presently of minor significance in
New England.

Trade name

Table 2. Average I insect injury on fruit at harvest in Previous
Year IPM, First-Year IPM and Check commercial orchards in
Massachusetts, 1982.

1982 Injury ("a)

Previous-Year'^ First Year
IPM blocks IPM blocks
Pests (25 blocks) (11 blocks)

Check

blocks)

.83

,26

,86

,47

,04

,01

Tarnished Plant Bug 1.12

Plum Curculio 0.43

San Jose Scale 0.84

European Apple Sawfly 0.87

Gypsy Moth 0.01

Apple Maggot Fly 0.01

Leaf Roller 0.02

Codling Moth 0.0

IVhite Apple Leafhopper 0.0

Green ^ruitworm 0.01

Sooty Mold fungus 1.00

.76

.37

.61

.83

.06

.04

.02

.12

Total % injury 4.31 3.81 3.51

Based on on-tree survey of 600-2,000 fruit per block at harvest (100
fruit per tree from each of 2 trees adjacent to each trapping station),

■^Orchards which have been on an IPM program one or more years.

Mite populations .

Table 3 contains results of mite sampling performed in IPM and
check commercial orchards in 1982. Relatively high numbers of mites
per leaf in IPM orchards probably have more to do with sampling methods
than with any differences in control efficacy among blocks.

In IPM blocks samples were taken on a weekly basis proximal to
"hot spots" and were initiated when signs of bronzing or active mites
were observed. Samples in Check orchards, on the other hand, were
collected at random intervals, often after growers had treated for
mites .

There is an apparent association between higher prey mite numbers
and higher predatory mite numbers. However, from a pest management
perspective, 1982 was not a good year for biological mite control in
Massachusetts. In most IPM blocks the early part of the growing season
(through early July) saw few mite problems. Heavy rainshowers apparent-
ly washed adult mites off the leaves and cool wet weather was not con-
ducive to mite reproduction. Bronzing was mild at this time and trees
were growing vigorously.

In July and August, however, hot dry conditions resulted in rapid
mite buildup in many blocks. ERM numbers above treatment level con-
tinued in some cases into September. Red mite eggs were observed in

Table 3. Mean abundance of pest and predaceous arthropods at peak

sample populations on foliage in Previous-Year IPM, First-Year IPM,
and Check blocks, 1982.

Species^

Mean abundance/Sample unit'

IPM Blocks

47.

,02

43.

11.

,31

,39

,65

New

Check

IPM Blocks

Blocks

51.8

1.1

3.0

0.4

0.04

0.01

39.9

16.0

21.0

5.7

21.5

2.0

0.19

0.0

0.36

0.0

0.36

0.0

European red mite
Two spotted mite
A. f allacis
Green aphids
A. aphidimyza
Syrphid spp.

Leafminers'

(1st

gen

(2nd

gen

(3rd

gen

Sample unit = Individual leaves for mites and leafminers, and foliar
terminals for aphids and aphid predators.

^In 1982, mite sampling was performed near "hot spots" when initial
leaf bronzing or numerous active mites were noticed. In check blocks,
trees were sampled randomly.

■'^First generation mine counts in 21 previous and 9 new IPM blocks; 2nd
generation mine counts in 20 previous and 11 new IPM blocks; 3rd gen-
eration mine counts in -23 previous and 12 new blocks.

the fruit calyx in significant numbers in 2 blocks. Amblyseius
fallacis , our major predatory mite, was present in low numbers in
1982, a phenomenon reported by other Northeast and Canadian tree fruit
entomologists. A. fallacis was first observed on August 4, after
red mite and two spotted mite populations had reached treatment levels
at several sites. A. fallacis was ultimately found in 211 of IPM
blocks, but the highest recorded sample had only 0.3 predators per
leaf. IPM blocks averaged 0.03 A. fallacis per leaf compared to 0.01
per leaf in the checks.

We are not able to explain why predator mite numbers were low in
1982 (down from an' average of 0.2 per leaf in 1981). However,
A. fallacis appeared too late and in too few numbers to affect red
and two spotted mite numbers in monitored orchards.

Insecticide, aphicide

and miticide use ,
blocks (average 6

Previous-Year IPM blocks (average 6.3 insecticide sprays, range
4 to 10) and First-Year IPM blocks (average 7.0 insecticide sprays.

range 4 to 10.4) received 28% and 20% fewer insecticide spray
applications, respectively, than check blocks (average 8.8 sprays,
range 4 to 12) (Table 4). Check blocks received no aphicide sprays.
Previous-Year IPM blocks averaged 0.2 aphicide applications and
First-Year IPM blocks averaged 0.4 such sprays. Miticide spray
applications were 32% and 43% lower in Previous -Year and First-Year
IPM blocks, respectively, than in checks, due in part to grower
interest in preserving and encouraging predatory mites.

Dosage equivalents of pesticides that were used followed sim-
ilar patterns. DE of insecticide used in Previous-Year or First-
Year IPM blocks were 30% and 21% less than in the checks. DE of
miticide used were 17% and 9% less than those of the checks. DE of
aphicide used were 20% and 30% more than those of the checks, however,

Table 4, Numbers of pesticide treatments and dosage equivalents of
pesticide applied for insect and mite pest control in IPM and
check blocks, 1982.

Previous Y

ear

First Year

Check

Treatment

IPM

blocks

(24)

IPM blocks

(12)

blocks (7)

Oil

0.8

1.0

0.6

Insecticide

6.3

7.0

8.8

Miticide

1.3

1.1

1.9

Aphicide

0.2

0.4

0.0

Dosage

Equivalents

Oil

0.7

1.0

0.6

Insecticide

5.5

6.2

7.8

Miticide

1.0

1.1

1.2

Aphicide

0.2

0.3

0.0

Dosage equiva

lent ■■

= Actual

pesticide

t: t: ^

rate/100

-:r^ i ^T-^. .

gal.

Amount recommended in New England
Pest Control Guide

Cost benefit analysis .

Both Previous-and First-Year IPM blocks realized substantial
savings in insecticide spray materials and spray application costs
compared to check blocks (Table 5), However, cost inputs for oil,
aphicide and miticide materials were higher in both types of IPM
blocks compared to the checks. In addition, higher levels of fruit
injury resulted in $34.65 and $11.55 more fruit lost due to insect
injury compared to the checks in Previous -Year and First-Year IPM
blocks, respectively. Cost savings from IPM practices averaged

$17.64/A in Previous -Year IPM blocks, and $3.25/A in First-Year
IPM blocks.

It is interesting to note that in 1982, the most favorable
cost/benefit ratio existed in 15 1001 Cooperator IPM blocks. While
the cost of oil, miticide and aphicide sprays was greater in such
blocks compared to the checks, substantial per-acre savings in
insecticide materials and application costs, combined with a slight
reduction in the value of fruit lost due to insect injury, resulted
in an average net benefit from IPM of $56.95 per acre.

This finding may illustrate the potential value to growers
from complete rather than partial implementation of an IPM system.
This is particularly true with regard to the use of reduced pesti-
cide rates and the need for cooperation between pest manager and
grower to insure optimal spray timing. This latter factor is of
particular significance inasmuch as IPM spray decisions frequently
are made when pest levels have reached an action threshold level.
Substantial delays in spray application beyond this point may
result in higher levels of injury than if growers had followed a
traditional preventative program.

Pesticide use, insect injury and cost benefit analysis, 1978-1982 .
Figure la details trends in dosage equivalents of insecticide
used in IPM vs. check blocks since the inception of the Apple IPM
pilot program. Check insecticide use remained near the level used
prior to IPM program initiation while cooperating IPM blocks have
experience an overall 26% reduction in insecticide DE used. Similar
results are evident in Figure lb, detailing miticide DE used from
1978-1982. In this case, IPM blocks have used an average of 54%
fewer such materials than check blocks.

Fruit injury at harvest was lower in IPM blocks in 3 out of 5
years in spite of lower pesticide use, averaging 13°6 less fruit
injury than checks.

Table 6 contains results of cost benefit comparisons performed
from 1978-1982. Data from 1980 to 1982 are subsets of all IPM blocks
which account for degree of cooperation with specialist recommenda-
tions, a parameter which may strongly influence program results.

Over the 5 year span of the pilot program, highly cooperative
IPM growers realized an average net benefit of about $82.00 per
acre, exclusive of scouting costs. Private scout consultants
presently are offering IPM services to growers for $20-$30 per acre,
indicating a potential savings to growers for continued IPM effort.
Growers who plan to perform their own scouting will be able to save
even this scout/consultant fee and should be able to realize a more
favorable net benefit.

' v.

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Table 6. Cost/benefit analysis of arthropod pest control practices
in IPM vs Check blocks, 1978-1982.

Difference IPM vs

Check

1978

1979

1980^

1981^

1982^

Cost of materials

Oil
Insecticide

Miticide
Aphicide

- $5.81
-$12.51
-$15.83
0.0

+$ 0.23
-$51.64
-$14.59
-$ 0.11

-$ 2.84
-$42.50
-$19.49
-$ 4.30

-$ 2.62
-$37.01
-$16.85
0.0

+$ 1.30
-$51.92
+$ 6.37
+$ 3.33

Cost of pesticide
application

-$ 9.64

-$16,05

-$ 7. 32

-$ 8.96

-$12.18

Value of fruit lost
due to insect injury

-$53.37

-$40.46

-$16.42

+$25.26

-$ 3.85

Avg. net benefit
from IPM

+$97.16

+$122.83

+$93.37

+40.18

+$56.95

Five year average net benefit from IPM +82.10

'1980 data = Complete cooperator blocks.

1981 data = Previous- Year IPM blocks.

1982 data = Complete cooperator IPM blocks

C
CI

Clt

Figure 1. Trends in Pesticide Usage and Insect Injury to Fruit, 1977-1982.

Insecticide Usage
IPM»— — • X - 6.3
CHECK O O X • 8.5

b. Hiticide Usage

CHECK O O ^ ~ ^-^

(8)

(9) (7)

-N.

V-

■^-^

(8)

(16)^

'''(19)-""^

(36)

(18)

—i 1

•77 '78 '79 '80 '81 '82
<? 26Z reduction in IPM Blodcs

-4-

-I-

■+-

'78 '79 '8b '81 '82
54J reduction in IPM Blocks

1 ■■

Total Insect Injury to
Fruit at Harvest

tS '7^ ^iJ ^81

@ 132 reduction in IPM Blocks

Cooperative Extension Service
U.S. Department of Agriculture
University of Massachusetts
Amfierst, Massachusetts 01003

OFFICIAL BUSINESS

PENALTY FOR PRIVATE USE, $300

POSTAGE AND FEES PAID
U.S. DEPARTMENT OF
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FRUIT
NOTES

PREPARED BY
DEPARTMENT OF PLANT AND SOIL SCIENCES

COOPERATIVE EXTENSION SERVICE,
UNIVERSITY OF MASSACHUSETTS. UNITED
STATES DEPARTMENT OF AGRICULTURE AND
COUNTY EXTENSION SERVICES COOPERATING.

EDITORS
W. J. LORD AND W. J. BRAMLAGE

Vol. 48 No. 2
SPRING ISSUE, 1983

Table of Contents

FRUIT NOTES Subscription Form

Nutritional Problems in 1982 and Suggestions for
Fertilization of Apple Trees in 1983

Effects of Type of Nitrogenous Fertilizer Applied
Under Sturdeespur Delicious Trees on Exchangeable
Elements in the Soil

Preliminary Findings From the Multi-State
Cooperative Apple Interstem Planting

Future of Tree Fruit IPM in Massachusetts

Publication Available

Sampling Soil for Nematodes

Pruning Plum Trees

A Visual Monitoring Trap for the Apple Blotch
Leafminer

Are High Density Strawberries on Ridges For You?

Suggestions for Use of Calcium Sprays in 1983

An Up-date on Calyz-end Rot, and Report of an
Apple Leaf Spot Caused by the Fungus

Sclerotinia sclerotiorum

Use of Promalin to Increase Branching of Young Trees

I Issued by the Cooperative Extension Service, Daniel I. Padberg, Director, in furtherance
I of the Acts of May 8 and June 30, 1914; United States Department of Agriculture and

County Extension Services cooperating. The Cooperative Extension Service offers equal

opportunity in programs and employment.

NIITRTTTONAL PROBLEMS IN 1982
AND SUGGESTIONS FOR FERTILIZATION OF APPLE TREES IN 1983

Wi lliam J . Lord
Department of Plant and Soil Sciences

Prospects for a heavy bloom in 1983 are not too likely follow-
ing the large crop in 1982. However, there are ample flower buds
for a good crop in 1983.

The analysis of leaf samples from commercial orchards showed
that potassium (K) and magnesium (Mg) was deficient in many
orchards in 1982 and boron (B) was generally low. Visual obser-
vations of Mg deficiency were quite prevalent on both apple and
pear trees, which is unusual, and perhaps resulted from leaching
of this element by the heavy rainfall in June (9.6 inches at the
Horticultural Research Center). It is possible that leaching of
K and Mg occurred both from the leaves and soil. Mineral analysis
of Mcintosh fruits from 24 orchards sampled shortly prior to
harvest in 1982 showed that calcium (Ca) levels were low. Two
blocks of trees in each orchard were sampled. Only 5 of the 24
orchards produced fruit in both blocks with Ca levels high enough
to clearly predict that their fruit had a high potential for long-
term storage of good quality fruit.

Information on the Leaf Analysis Reports indicated that some
growers continue to apply a "complete fertilizer". Cost could be
reduced by using fertilizer that contains no phosphorous (P) since
there is no evidence that our apple trees need this element beyond
what is present in the soil.

With the above observations in mind, we present the following
suggestions as a guide for fertilization in 1983.

Nitrogen (N) : Most orchards had a large crop in 1982, there-
fore! the trees may be low in available N for utilization this spring,
We suggest higher rates than normal of N this year unless the trees
were excessively vigorous in 1982 or were heavily pruned this past
winter.

Potassium (K) : Over 901 of the leaf samples were deficient,
probably due to the demand for this element by the large crop, and/or
leaching because of heavy rainfall.

The leaf scorch symptoms of K deficiency may be confused with
the leaf margin burn from calcium chloride sprays. However, unlike
leaf burn from calcium chloride sprays, the scorch of leaf margins
due to K deficiency progresses from the older leaves to the younger
leaves of current season shoots as the season advances. The scorch
may turn gray in color and leaf fall may occur late in the growing
season .

-2-

The K requirements of apple trees with a large crop are high
because the fruit utilizes about 3 times as much K as N. Since
the quantity of K stored by the tree is extremely small, it seems
important to supply adequate K this spring on trees that had heavy
fruit set in 1982.

The requirements of apple trees for K (expressed as K2O), based
on potential yields, are as follows: (a) less than 15 bu: 1.3 lbs.
/tree; (b) 15 to 25 bu: 1.3 to 2.7 lbs/tree; and (c) more than
25 bu: 2.7 to 4.3 lbs/tree. It is necessary, however, to maintain
a balance among the essential nutrients for apple trees. For
example, excessive levels of K can reduce both leaf and fruit Ca.
Therefore, we strongly urge that you participate in our leaf
analysis program to more accurately determine the K needs of your
apple trees .

Calcium CCa) : Our suggestions for meeting the Ca needs of apple
trees can be found in another article in this issue of FRUIT NOTES.

Boron (B) : B can be supplied to apple trees either by foliar
or soil applications. Use the most economical and convenient
method. However, it is safest to apply all elements as a fertilizer
except in emergency situations .

Soil applications of boron should be applied to orchards every
3 years. The rate of application per tree vary with tree age and
size. In low density orchards, apply h pound of borax (11.1°
actual B) or its equivalent under young trees coming into bearing ,
h to 3/4 pound to medium age and size trees and 3/4 to 1 pound to
large or mature trees. Be sure to note the percent actual B in
the fertilizer being used to supply this element . B containing
fertilizers vary from approximately 11 to T\\ actual B.

In medium and high density orchards (115 trees/acre or higher),
it might be best to apply B on an acre basis. We suggest the follow-
ing rates per acre of borax (11.1% actual B) or its equivalent:
(a) trees 4 to 7 years of age - 12 lbs; (b) trees 8 to 15 years of
age - 12 to 24 lbs; and (c) trees 16 to 30 years of age - 24 to
48 lbs.

When the soil application of B is followed by a wet spring,
it may be advisable to apply 2 foliar applications of B the follow-
ing year.

per acre in each of the 2 applications. For young orchards, the
addition of 1/2 pound of Solubor per 100 gallons (dilute basis)
to the first 2 cover sprays meets the B requirements of these
trees. Reports of New York State indicate that sprays can be con-
centrated up to 8X with satisfactory results.

Leaf samples from orchards treated with Solubor have indicated
adequate leaf boron levels but the fruit was deficient in this
element . Whether or not B applied as a fertilizer more adequately
meets the B requirement of apples than foliar applied B is not
known by us.

Magnesium (Mg) : Deficiency symptoms of this element are char-
acterized by necrotic (brown) areas between the veins. The older,
basal leaves on shoots and spurs are usually affected first, and
as the season progresses the injury symptoms appear on the younger
leaves. The deficiency symptoms frequently become apparent in
late July and early August. By late summer, the shoots on which
leaves show Mg deficiency may be defoliated except for a few
leaves near their terminals. Mg deficiency increases fruit drop
at harvest.

Weather conditions may have been responsible for the frequent
symptoms last year and the question is what to do if you suspect
or know that you had trees low in Mg. If you have been applying
a dolomitic limestone on a regular basis (dolomitic limestone con-
tains magnesium), no corrective procedures should be necessary.
However, take leaf samples again for analysis in 1983.

If you have not applied dolomitic limestone recently and you
suspect low Mg levels in your trees, we suggest applying this kind
of lime this spring.

Manganese (Mn) : Apple leaves from trees showing Mn deficiency
in 1978 had 12 to 15 ppm of this element which is much below the
desired levels of 30 to 60 ppm. Mn deficiency symptoms are char-
acterized by interveinal fading of chlorophyll with the veins re-
maining green. For those who are unfamiliar with the symptoms of
Mn deficiency, we refer vou to the photograph that appeared in the
May/June 1978 Issue of FRUIT NOTES.

Mn deficiency should be corrected on trees sho\\ring considerable
foliage damage. Although we have no definite proof, Mn deficiency
appeared to be associated with excessive fruit drop on a few trees
in orchard in 1977. Mn deficiency can be corrected by foliar
applications of manganese sulfate or of a fungicide containing Mn.
Apply manganese sulfate at about first cover at the rate of 3 lbs.
per 100 gallons of water. If using a Mn-containing fungicide, 2 or
3 applications are necessary with timings about petal fall, first
and second cover.

-4-

Zinc (,Zn): Based on optimum levels of Zn established by Warren

Stiles7~Cornell University (See FRUIT NOTES 47(2):20-26, 1982] some

of our orchards continue to be low in this element. W. Stiles believes

that apple trees require approximately 2 lbs. of Zn per acre annually

if applied as inorganic salts in dormant sprays or approximately 0.2

to 0.3 lbs. of actual Zn applied as foliar sprays of EDTA chelates

(3 to 5 lbs/acre) .

**********

EFFECTS OF TYPE OF NITROGENOUS FERTILIZER APPLIED UNDER STURDEESPUR
DELICIOUS TREES ON EXCHANGEABLE ELEMENTS IN THE SOIL

William J. Lord, John Baker and Richard A. Damon, Jr.

In a previous issue of FRUIT NOTES (Vol. 45, No. 4), we reported
our findings on the effects of calcium nitrate (Ca(N02)2' amnionium
nitrate (NH.NO^) or potassium nitrate (KNO^) applied annually from
1972 through 1979 on soil pH , the nutrient levels in leaves, on bitter
pit, and fruit calcium (Ca) levels. To briefly review these findings,
neither Ca(N0^)2 nor KNO, affected soil pH , whereas NH-NO^ increased
soil acidity. Nitrogen [N) source had little influenc? on N, potassium
(K) , magnesium (Mg) , or Ca content of leaves, no appreciable influence
on fruit Ca and no effect on the incidence of bitter pit.

Here we present our findings on the effects of N sources applied
annually since 1972 on exchangeable Ca, Mg and K in the soil (Table 1) .

Table 1. Effects of N sources applied annually since 1972 on
exchangeable Ca, Mg and K in the surface 6 inches of soil.

Meq/100 g in soil of:

Treatment

Ca Mg

1978

Control
KNOj
NH^NOj
Ca(N02) 2

Control
NH^NOj

Ca(N02)2

, 40ab^

,00b

.04c

,44a

.34a

.36b

. 35a

.06a

.02b

.45b

1981

.90a

.57b

,26b

,30a

,15a

.98a

.ISb

.73a

8.33a 1.50b 0.77a

Untreated soil between trees.
y

Numbers in a column for each year followed by a different letter

are significantly different at odds of 19 to 1.

-5-

In 1978 soil treated with NH^NO^ for 7 consecutive years had
less exchangeable Ca and Mg than untreated soil from between
the trees. In contrast exchangeable Ca was similar in untreated
soil and in soil fertilized with KNO^ or Ca(NO,)^. Soil K was
higher under the trees than between the trees out N source did
not influence K, which had been applied equivalently under all
trees .

the

The
el imi
or

NH^NOj
secut ive
those obt
tially in
our study
tree and
applied i

original experimental design was changed in 1980 with
nation of the KNO, treatment but with the continuation of

i(N0,)2 applications. Our data in 1981 after 10 con-
annual applications of Ca(N0,)2 are in agreement with
ained in 1978 (Table 1) in tnat its use has not substan-
creased the amount of exchangeable Ca in the soil. Thus,
continues to emphasize the difficulty of affecting soil,
fruit Ca when fertilizing with CaCN0,)2 because the amount

s small when it is based on the N needs of the trees.

*******

PRELIMINARY FINDINGS FROM THE MULTI -STATE
COOPERATIVE APPLE INTERSTEM PLANTING-"- ' ^

William J . Lord
Department of Plant and Soil Sciences

The preliminary results from a cooperative interstem plant-
ing established in 10 states in 1976 are published in the Fruit
Varieties Journal, 1982 (Vol. 36, No. 1) and authored by David
Ferree of the Ohio Agricultural Research and Development Center,
Wooster, Ohio. The purpose of this multi-state planting is to
study the growth and yield potential of 2 scion cultivars with
an M9 interstem for dwarfing on 3 vigorous rootstocks under a
diversity of climatic conditions.

Trees for the plantings were propagated by double grafting
a 6-inch stempiece of M9 on scions of Sturdeespur Delicious or
Empire and on rootstocks of MMlll, Ottawa II or Antonovka Seed-
lings. Ottawa II and Antonovka rootstocks were selected because
they provide good anchorage and cold hardiness. MMlll served as
the control. This rootstock has shown good soil adaptability
but lacks precocity when used as the understock on 2-piece trees,

States cooperating in this study were Illinois, Indiana, Iowa,
Kansas, Kentucky, Massachusetts, Michigan, Missouri, Ohio and
Wiscons in.

Editors Note. The trees for the Massachusetts planting were
exceptionally poor, causing tree loss the year of planting, poor
growth of surviving trees and lack of fruitfulness . Other inter-
stem trees were planted on this site in 1979, and no tree loss
has been experienced and growth is vigorous.

■6-

The data from the multi-state plantings, summarized by
Ferree after the first 5-years of study showed that tree losses
occurred at all sites except in Illinois and Iowa. The highest
tree losses were experienced in Massachusetts and Wisconsin.
The losses were attributed to poor tree quality. Trees on the
Kentucky site experienced severe frost heaving in 1978. Regard-
less of rootstock, the growth on the trees was weak in 1979 and
they were removed in 1980.

Tree size based on cross- sectional area was quite variable
among the planting sites. In general, the trees in Illinois,
Iowa, Kansas, Missouri and Ohio were larger than those in Massa-
chusetts, Michigan, Wisconsin and Indiana. Those on the Indiana
site were smallest.

Compilation of the data from the 9 sites indicated that the
trees on MMlll were 15-201 smaller than those on Antonovka seed-
ling or Ottawa II. The trunk circumference and branch spread of

the Empire trees were larger than those of Sturdeespur on com-
parable rootstocks.

The trees were planted with the stempiece 2 inches above
the soil line and the development of root suckers had been of
concern on all sites. Trees on Ottawa II have tended to pro-
duce fewer root suckers than Antonovka or MMlll, particularly in
Kansas, Massachusetts and Ohio. Trees in Missouri and Ohio
produced nearly twice as many suckers as in other states. Of
particular interest in areas where fireblight is of major concern
is the fact that several states observed fireblight strikes on
Antonovka root suckers in 1981 .

The trees produced their first crop in 1979 and the Empire
trees showed the tendency to bear earlier than Sturdeespur Deli-
cious. However, adequate data are yet not available to evaluate
the yield efficiency of the various scion/rootstock combinations.

Ferree summarized the preliminary findings from the multi-
state interstem planting by stating "...it is clear that signi-
ficant differences exist in root suckering potential of vigorous
rootstocks used as root systems for interstem trees. An assoc-
iation also appears to exist between increased suckering and
vigorous scion growth. We have also confirmed that producing inter-
stem trees through double grafting should be avoided because of
poor tree quality and general lack of vigor is considered as a
major factor contributing to poor early tree performance in
several of the test sites".

«« 7b #« «« «

Future of Tree Fruit IPM in Massachusetts

17 7

W.M. Coli , R.J. Prokopy" and W.J. Manning

As we have stated previously, 1982 was the final year of
the Apple IPM pilot program. We anticipate the future of tree
fruit IPM in the state to be two fold:

1) Continued extension involvement - Federal funds for
IPM will continue to come to the state on a formula
basis at least through FY 1983. While no one can accu-
rately predict the level of funding or the security of
such funds given the cost-cutting emphasis of the present
administration, IPM monies are a high priority item in
USDA's budget and appear to be reasonably safe from the
"budget axe."

The 1983 growing season will see the implementation
of IPM programs in cranberries, forage crops, and potatoes,
thereby substantially reducing the amount of USDA money
available for continuing an apple IPM program.

Nonetheless, the Extension administration has ac-
cepted a proposal to continue a part-time IPM Specialist
position at the University for the purpose of maintaining
a scaled-down apple program effort, A major factor in
this decision was the willingness of many large and small
growers throughout the state to pledge their financial
support of such an effort. As of this writing, $3,500
has been pledged by growers, for which we extend our
thanks .

Mr. William Coli will remain in his present capacity
of Tree Fruit IPM Specialist, with additional responsibil-
ities in the area of peach and pear pest management and as
overall coordinator of the multi-crop Massachusetts IPM
program, Mr. Coli will serve as a resource person for
pest management related questions. In addition, he will
continue to take principal responsibility for development
of the twice-weekly insect and disease pest status messages
based on his own scouting in commercial orchards at several
locations as well as on reports from cooperating private
scout/consultants, and regional fruit specialists. As in
the past, apple scab spore maturity information will be
provided by W,J, Manning, Dan Cooley and Chris Becker in
the Department of Plant Pathology.

Extension Pest Management Specialist

Extension Entomologist

Extension Plant Pathologist

-8-

2) Private sector implementation - During the course of

tlie apple pilot program, numerous growers have received
IPM training or have assigned some member of their
orchard staff to receive such training. In most cases,
these individuals will be able, with some support from
extension, to continue with an IPM approach on their own.

For other growers, there presently are 3 individuals
offering private IPM scouting/consultant services in the
region. These three, and a fourth person who recently
announced similar plans, all received their initial IPM
training with the Massachusetts apple IPM program and
should provide growers with an excellent choice of avail-
able services.

The individuals we refer to and their addresses are:

Clarence Boston
242 Cayenne Street
West Springfield, MA

David Gordon
51 Pond View Drive
Amherst, MA 01002
(413) 523-5293

Glenn Morin/Dr. Robin Spitko

D.B.A. New England Fruit Consultants

P.O. Box J

Lake Pleasant, MA 01347

(413) 367-9578

PUBLICATION AVAILABLE

The Northeast Regional Agricultural Engineering Service Publi-
cation - 4 entitled "Trickle Irrigation in the Eastern United States"
may be obtained by writing to the Cooperative Plan-Service, Agri-
cultural Engineering Building, University of Massachusetts, Amherst,
MA 01003. There is a $1.50 charge for the publication. Make checks
payable to: Cooperative Extension Activity Fund.

Dr. Donald Elfving, Research Scientist, Simcoe, Ontario referred
to the above publication during his talk on trickle irrigation of
apple trees at the New England Fruit Meetings in January, 1983.
Elfving stated that NRAES-4 is a valuable guide for tree fruit and
small fruit growers interested in trickle irrigation. Information
is presented on advantages and potential problems; plant-soil-water
relationships; system components, specific crop recommendations; system
planning; designing laterals and submains ; preventing line clogging,
and water application calculations.

-9

SAMPLING SOIL FOR NEMATODES

Dr. Richard Rohde
Department of Plant Pathology
University of Massachusetts

The best time to take soil samples for counts of nematode
populations is mid-May through early-July and in mid-September
through October. Nematodes are distributed in clusters
through the field, thus it is important to collect soil from
several areas. For each 5000 sq. ft. area take 10 or more
sub-samples. Samples should be taken at soil depths of 2-10
inches and can be collected with a trowel, spade or soil sampl-
ing tube. On sites sampled prior to planting, obtain the soil
samples where you think the tree rows will be located. When
sampling an established orchard, obtain the soil for nematode
counts from the root zone of the fruit trees. The sample should
also include small roots of the fruit trees since lesion nema-
todes, the most common orchard nematode in our area, is in the
roots during part of its life cycle.

Mix the soil in a bucket and then put 1 quart of the mixed
soil in a plastic container. Samples can be stored in a refrig-
erator for several months but should not be exposed to high
temperatures such as could occur in a plastic bag lying in
direct sunlight or in a car trunk on a hot day. Also, dried-
out soil is useless.

The soil samples for nematode counts should be sent to your
Regional Fruit Specialist, or directly to Dr. Richard Rohde,
Department of Plant Pathology, Fernald Hall, University of
Massachusetts, .Amherst 01003.

********************

PRUNING PLUM TREES

James F. Anderson
Department of Plant and Soil Sciences

There has been an increased interest in the production of
plums in Massachusetts, especially on the part of growers oper-
ating farm markets. Since the apple is the major tree fruit
in Massachusetts, most research and extension activity has been

-10-

dcvotcd to that crop and little attention has been given to tlic
pi uni .

Tlie discussion that follows is offered as a brief guide to
the training and pruning of plum trees.

Training Young Trees

There is a marked difference in the growth habit of plum
trees depending on type and variety. Some are decidedly up-
right while others are distinctly spreading in growth habit.
Regardless of growth habit, most are probably best trained as
a central or modified central leader tree.

The plum tree should have 5 or 6 scaffold branches spaced
about 6 inches apart and spirally around the leader. On upright
growing trees, it would be advisable to spread the branches to
improve the trees structure. Excessively long branches should
be shortened, preferably by cutting it back to an outward grow-
ing lateral. Heading-back cuts may be used when necessary to
shorten and/or stiffen the scaffold branches.

Pruning Bearing Trees

Flower buds are formed laterally on current seasons growth
and on the extension growth of spurs. The flower buds are sim-
ple, containing 1 to 3 flowers, but no leaves. The terminal
bud of both shoots and spurs are leaf buds. European varieties
fruit more heavily from spurs; Japanese types fruit heavily from
both shoots and spurs. The shoot of a Japanese plum is similar
to the peach in flower bud development.

Annual pruning helps to maintain a supply of new wood on
which the flower buds can form. For the Japanese varieties, an
annual shoot growth of 10 to 20 inches for young trees and 10 to
12 inches for older bearing trees is desired. European varie-
ties should average 9 to 18 inches of annual shoot growth for
young trees and 6 to 10 inches for older bearing trees. After a
plum tree begins bearing, an annual thinning out of watersprouts
and branches growing towards the center of the tree will con-
stitute the major part of the pruning operation. The tree should
be kept open to allow for good light penetration, air movement
and spray coverage. Control of brown rot will be much easier if
the tree is prevented from becoming too dense. Keeping the trees
open will also maintain fruiting throughout the lower and inner
portions of the tree. Some heading-back cuts may be necessary to
shorten and/or stiffen the scaffold branches.

Removal of Black Knots

The plum is particularly susceptible to the fungus disease,
black knot, which may be identified in the dormant season by

black swellings or cankers on the branches. The principal control
for this disease is to prune off and burn these knots. Remove
small brandies entirely. On larger branches, cut to an outward
growing lateral. In any case, the cut should be made at least
six inches below any evidence of the disease and all diseased wood
should be removed from the orchard. This may necessitate more
drastic pruning than would be recommended ordinarily.

***********

A VISUAL MONITORING TRAP FOR THE APPLE BLOTCH LEAFMINER"^

2 3 4

Thomas Green , William Coli , Geoffrey Hubbell ,

and Ronald Prokopy
Department of Entomology

For the past 3 years, we have attempted to develop a visual
monitoring trap for the apple blotch leafminer, Phyllonorycter
crataegella . This insect, an organophosphate-resistant pest of
apple foliage, is implicated in premature leaf and fruit drop
and reduction in fruit set the following season. A pheromone
trap is available for a related species, P. blancardella (spotted
tentiform leafminer) , but this pheromone is not effective in
attracting P. crataegella , the predominant species in Massa-
chusetts commercial orchards . We theorized that if a visual moni-
toring trap were available for P. crataegella, the need for a
pre-bloom insecticide application against the overwintering gener-
ation adults might be determined from trap capture levels. Here,
we present a brief summary of our research on the development and
utility of a visual trap for P. crataegella .

Results

In 6 experiments , we determined the number of P. crataegella
captured on sticky-coated (=Tangle-Trap^) traps painted with
commercially available paints of various colors. The consistently
highest captures in these experiments were on traps painted with
Sherwin-Williams Tartar Red DarkR Enamel. Results of 2 of the
experiments are presented in Table 1.

1
We wish to express our appreciation to the following IPM field
scouts for assistance with data collection: David Gordon, Kath-
leen Leahv, Joseph Parella, Douglas Roberts, and Roy Zahnleuter

2
Extension Technician

3
Extension Pest Management Specialist

4
Research Assistant

5
Extension Entomologist

-12-

Table 1. Comparison of P. crataegella captures on 20 x 30 centi-
meter* (cm) horizontal ( s t i cky - s i de - up ) traps of various colors
positioned 1.5 meters** (m) above ground in the interior part
of the tree canopy.

Experiment

Color

Avi

erag(

2 number

Color

Avi

erage number

crataegella

trap

per

trap

per

trap

Red

610

Red

1580

Green

548

Green

1267

Orange

500

Light

Gray

1200

Gray

486

Black

1141

Foil

470

White

1126

White

467

Medium

Gray

1113

Yellow

447

Dark G

ray

976

Blue

411

Clear

368

Black

356

One centimeter = 2.54 inches
One meter = 39.37 inches

The next step in the development and utilization of a visual
trap was to evaluate the influence of the orientation of the trap
on its effectiveness in capturing P. crataegella . The orientations
tested were: (1) horizontal, sticky-side-up ; (2) horizontal, sticky-
side-down; (3) vertical; (4) 90 degree (tent- shaped) , sticky-side-
up; and (5) 90 degree (V-shaped), sticky-side down. Captures were
higher on the horizontal, sticky-side-up traps than on those with
the vertical or sticky-side-down orientations (Table 2).

Table 2. Comparison of P. crataegella captures on 20 x 30 cm red
traps of various orientations, positioned 1.5m above ground
in the interior part of the tree canopy.

Orientation of trap Average number P. crataegella per trap

Horizontal, sticky-
side-up 131

90° (tent-shaped) ,

sticky-side-up 85

Vertical 12

90° (V-shaped) ,

sticky-side-down 10

Horizontal ,

St icky- side-down 5

13-

on horizontal
positions within

block of semi-
iameter. The in-tree
alfway between the
alfway between the
top, halfway between
ove ground, . 5 m
ground, 0.5 m in
he trunk and 1.5m
st leafminers (Table

Table 3. Comparison of P. crataegella captures on 20 x 30 cm
horizontal red traps ( s t i cky - s i de - up ) at various positions
within the tree.

We then

compared P,

. crataegella

captures

(sticky-side-

up) red traps placed at

various

the tree. Th

lis ex

periment was conducted in

dwarf trees,

ca. 5

m in

height and 4

m in

positionings

were :

(1)

0.5 m above

ground ,

trunk and dri

pline

; (2)

1.5m above ;

ground.

trunk and dri

.pline

; (3)

0.5m below

the tree

the trunk and

[ outermost

foliage; (4)

. 5 m a

out from the

tree

trunk ;

; and (5) 1.5

above

from the drip

• line .

Traps placed 0.5

from

above the ground (

position 4) captured

the mo

3).

Position of trap

Average number P. crataegella per trap

1.5m height ,

0.5 m out from trunk

1.5m height ,
halfway between
dripline and trunk

0.5 m height ,
halfway between
dripline and trunk

1.5m height ,

0.5 m in from dripline

0.5 m from tree top,
halfway between trunk
and outermost foliage

161

125

96
87

In the spring of 1982, the red horizontal (sticky- side-up)
traps were used in 21 IPM orchard blocks in Massachusetts. The
traps were placed 1.5 m above the ground and ca. halfway between
the tree trunk and dripline. Each week, as part of the regular
field scouting routine, leafminer adults were counted and removed
from the traps, and foliage was sampled to determine the average
number of mines per leaf. Cumulative average trop captures were
highly positively correlated with the number of mines per leaf
in the 21 blocks sampled. Figure 1 represents a regression of
mines per leaf on trap captures through 2 weeks after petal fall and
illustrates a prediction of 0.13 mines per leaf (the first gener-
ation Economic Injury Level for stressed trees) at a cumulative
average of 12 P. crataegella per trap.

14-

Conclusions

Sticky-coated, 20 x 30 centimeter red traps, hung at
height inside the canopy o£ apple trees, were effective fo
itoring P. crataegella adults. We recommend that the trap
at a rate of 1 per 0.8-1.2 hectares*, and that a pesticide
(oxamyl or fenvalerate) against the adults be applied befo
white shows on the flower petals if cumulative pre-bloom c
(from silver-tip through late pink) reach or exceed 6 adul
trap. This tentative action threshold is conservative, al
for both the reproductive potential of P. crataegella and
stress due to drought, calcium chloride burn, and/or mite
Additional work is planned for the 1983 season to further
this threshold and to develop an additional action thresho
unstressed trees. This trap should be valuable in reducin
need to wait until first generation mines appear before a
spray decision can be accurately made.

chest
r mon-
s be used

treatment
re any
aptures
ts per
lowing
for tree
injury,
validate
Id for
g the
leafminer

0.6r

0.5 -

0.4 -

AVG

MINES

PER

LEAFo.3

0.2

0.1

O ^

45 60 75

NO. LM PER TRAP

00 211

Figure 1. Regression of first generation mines per leaf on

visual trap captures in 21 commercial orchard blocks

One hectare = 2.471 acres

-15-

ARE HIGH DHNSriY STRAIVRERRIES ON RIDGES FOR YOU?

Dominic A. Marini
Regional Fruit and Vegetable Specialist
Plymouth Countv Extension Service
Hanson', MA 02341

High density systems with up to 58,000 plants per acre
planted three inches apart on ridges 8 to 12 inches high and 3
feet apart are presently receiving a great deal of attention.
Yields of up to 45,000 quarts per acre are reported; and many
grovvers are wondering if they should adopt this system. Here
are a few things to consider in arriving at a decision.

Is your soil suited to the ridge system? A fairly level,
well-drained site is a necessity. Breaking up the soil to a
depth of 16 to 18 inches vvfith a subsoiler, followed by deep
plowing, 10 to 12 inches deep, is practiced by growers who use
the system successfully. Specialized, expensive equipment is
needed for leveling the soil and constructing the ridges.

Soil fumigation is recommended for any system of growing
strawberries. It is essential to prevent losses from black
root rot and other soil-borne diseases in order to obtain the
high yields possible with this system. Overhead irrigation for
frost protection and to maintain ample soil moisture is also
recommended for all growers, but is more essential for the
ridge system since the ridges dry out much faster than level
beds. More frequent nitrogen fertilization is necessary with
the ridge system because of the leaching of nitrogen resulting
from irrigating more often. And greater attention to insect,
disease and weed control, and winter protection must be given in
order to obtain high yields. Maintaining the winter mulch is
more difficult because of the sloping sides of the ridges.

Extremely high yields are possible with the high density
ridge system of growing strawberries for large scale, top notch,
specialist strawberry growers with the proper site and soil
conditions. For the average grower operating on a small scale,
growing a variety of crops on hilly, rocky. New England soils,
such yields are not very likely. Most growers are probably bet-
ter off with the more conventional systems of matted row or
some sort of spaced runner system on 4 to 6 inch high raised
beds .

AAA*****

-16-

SUHGESTIONS FOR USE OF CALCIUM SPRAYS IN 1983

Mack Drake and William J. Bramlage
Department of Plant and Soil Sciences

Calcium chloride fCaCl-,) foliar sprays are recommended in
Massachusetts for all apple growers to increase the flesh calcium
(Ca) content. Higher flesh Ca can markedly reduce bitter pit,
cork spot and fruit breakdown during storage.

Apply foliar sprays of CaCl2, beginning 3 weeks after petal
fall and repeat at 2 week intervals totaling 6 to 8 applications.
Apply 6 pounds CaCl2 per acre per spray until mid-July. After mid-
July apply 8-10 pounds per acre per spray. Continue foliar CaCl2
until fruit are ready for harvest. Use a technical grade of CaCi-;,
such as Allied Chemical Dow Plake, 77-801 CaCl^. Other brands may
be equally suitable.

Experience in Massachusetts has shown that CaCl^ can be com-
bined with pesticide sprays. However, some growers nave observed
that the combination of Captan or Guthion (azinphos methyl) 50 WP
and CaCl^ may increase foliar burn. DO NOT MIX CaCl^ AND SOLUBOR
SPRAYS! ALWAYS DISSOLVE CaCl2 IN A PAIL OF WATER and add this
last, when the spray tank is nearly full, to insure that the CaCl2
is completely dissolved before spraying begins.

Foliar CaCl2 sprays may be applied as dilute (300 gallons/acre)
or up to lOX concentration (30 gallons/acre). In our research,
apple flesh Ca was increased more by concentrated than by dilute
sprays .

CaCl2 sprays can cause burn of leaf margins. Foliar injury
has been more serious on Mcintosh than on Delicious or Cortland.
Apple leaves are less susceptible to CaCl-, burn after mid-July.
Mcintosh growing on M7 may be more susceptible to foliar burn than
those on standard rootstock. Weak or injured trees may be more
susceptible to CaCl^ burn than healthv trees" To reduce the chance
of leaf burn, DO NOT REPEAT A FOLIAR CaCl^ SPRAY UNLESS ONE-HALF TO
ONE INCH OF RAIN HAS FALLEN SINCE THE LAST APPLICATION'.'

In 1982, 3 different materials were compared as suppliers of
foliar Ca at the University of Massachusetts Horticultural Research
Center. One was commercial CaCl^; the second was a proprietary
formulation of CaCl^; and the thnrd was a chelated Ca compound.
Rate of application^was 86 grams Ca per tree in a total of 8 appli-
cations. Fruit Ca was 115, 165, 155 and 158 parts per million
respectively, for control, CaCl2, Formulation 1 and Formulation 2;
the amount of the breakdown was 33, 7, 7 and 11 percent, respectively,
for fruit air stored at 32°F for 5 months and then held at 74°F for
7 days. These results agree with those of previous years, and show

-17'

the positive effect of increased fruit Ca in reducing storage
breakdown of Massachusetts-grown Mcintosh apples. We do not
recommend long term storage of Mcintosh apples with less than
150 ppm flesh Ca.

Questions have been asked about possible accumulations of
chloride (CI) in the soil. Chloride salts are highly soluble.
Research in the Netherlands showed that there was no annual build-
up or accumulation of chloride where annual rainfall exceeded
30 inches per year. Rainfall in all areas of Massachusetts
exceeds 30 inches per year.

Annual application of muriate of potash (potassium chloride)
for corn silage, vegetable crops and alfalfa in Massachusetts
usually exceeds 200 pounds per acre, supplying about 100 pounds
of chloride per acre. Only 35 pounds of chloride are applied
per acre when our recommendations for foliar CaCl-, sprays are
followed. Also, it is important to note that this 35 pounds of
chloride is applied in 6 to 8 increments of 4 to 6 pounds per acre
foliar application as compared to the 100 pounds of chloride in
one application for corn, vegetables and alfalfa.

WARNING : The initial pH of commercial CaCl^ in water is 10.3,
since small amounts of free CaO form Ca(OH) in water. There is
evidence that the high pH may reduce effectiveness of some pesti-
cides. It is therefore recommended that 2 quarts of 5% vinegar
be added per 100 pounds of CaCl2 to neutralize the excess (OH)
and bring the reaction of the spray solution to about pH 6.0.

**********

AN UPDATE ON CALYX- END ROT, AND REPORT OF AN

APPLE LEAF SPOT CAUSED BY THE FUNGUS

SCLEROTINIA SCLEROTIORUM

12 3

Christopher M. Becker , Daniel R. Cooley and William J. Manning

Department of Plant Pathology

Calyx-end rot of apple, caused by the fungus Sclerotinia
sclerotiorum , has been observed in Massachusetts orchards in recent
years. A report on fruit symptoms and losses in 1980 was published
in FRUIT NOTES 46(1) :l-3. During the 1982 growing season, calyx-
end rot was again prevalent in many Massachusetts orchards. S.
sclerotiorum was also found to cause a previously unreported leaf
spot .

Research Assistant
2

Extension Technician
3

Professor of Plant Pathology

-17a-
ADDENDUM

After this issue of FRUIT NOTES had gone to press, it came to
our attention that the recommendations for use of CaCl2 appear to
be in conflict with statements in the "Annual March Message to Massa-
chusetts Fruit Growers (1983)", issued by Ronald Prokopy, William
Coli and Thomas Green of the Department of Entomology. To avoid
confusion from "mixed messages", the following additional comments
are presented:

Beginning about 1975, in Massachusetts we recommended separating
the applications of CaCl2 and pesticides. However, for the past 5
years many Massachusetts growers have combined CaCl^ with pesticide
sprays without observed reduction in effectiveness of pesticides.
Nevertheless, as we warn on page 17, addition of CaCl2 can signifi-
cantly raise the pH of the spray solution, which theoretically can
reduce the effectiveness of the pesticides.

This past year. Dr. George Greene conducted experiments at Big-
lerville, PA which showed that while CaCl^ raised the pH of water
it caused no measurable increase in disease or insect damage to apples
when combined with the pesticides he was using. It should be noted,
however, that some other researchers have reported evidence of reduced
effectiveness of pesticides at these high pH ' s .

In 1982 a number of Massachusetts growers added vinegar to lower
the solution to about pH 6, as recommended on page 17, to their mix-
ture of CaCl2 and pesticides. There was no dissatisfaction with
results .

Nevertheless, since some researchers and some states have issued
warnings of possible ineffectiveness of vinegar as a remedy, the
following additional steps can be taken if a grower feels that they
are necessary .

1. Use CaCl^ of a higher purity grade. Technical grade (77-
80l)CaCl2 will affect pH somewhat more than high purity
grade materials. However, the higher purity grade is
much more expensive and less available.

2. Apply CaCl2 sprays separately from pesticides.

3. Use a commercial buffer rather than vinegar to lower the
pH. Some concerns have been published that acetic acid,
the chief component of vinegar, may not be stable over
long periods in the spray mixture. However, it should
also be noted that some commercial buffers may cause Ca
to precipitate from solution, thereby reducing the value
of the CaCl2 sprays.

It should be recognized that we are not recommending the above
steps. We are alerting growers to concerns that have been raised
elsewhere, and to steps that can be taken if they feel that these
concerns warrant extra precautions.

William J. Bramlage, William Coli and Mack Drake

18-

the

man-

Fig. 1. Developing Mcintosh fruit
with calyx-end rot.

In mid-June, 2-81 of the Mcintosh fruit observed in 8 of
10 orchards visited by disease management scouts, were developing
calyx-end rots CFig« 1) •
Delicious, Cortland, and
Macoun also had end rots,
but at lower rates. Most
infected fruits ripened
prematurely, or dropped
by mid-August. Despite
premature drop, disease
agement scouts recorded
average of 1.001 infected
fruit in 10 orchards dur-
ing a harvest survey
CFRUIT NOTES 48(1) :11) .

All orchards with
calyx-end rotted fruit
in mid-June developed a
previously undescribed
leaf spot. Spots were
1-3 cm in diameter,
light brown, and vis-
ible on both sides of
the leaf (Fig. 2) .
These lesions were not
bound by veins. Some
lesions were noticed
next to non-pollinated,
wilted blossoms, and
several lesions had
developed following
contact with young end
rotted- fruit . Numerous
other spots contained
an antherl in the center
of the lesion. Infected
leaves seldom had more
than one spot per leaf,
with lesions typically
larger than frog^eye
leaf spot (caused by
Physalospora obtusa ) or
"captan spot". In con-
trast to typical frog-
eye leaf spot, the
Sclerotinia lesions
were an even than with-
out concentric darkened
areas. Most infected
leaves turned yellow

Fig

Mcintosh leaf with
tinia leaf spot.

Sclero-

from an apple blossom

-19-

within several weeks and dropped by mid-July to mid-August.

Isolations from the center or edge of these foliar infections
onto sterile petri plates of potato carrot agar consistently
yielded the fungus Sclerotinia sclerotiorum . This was the first
reported isolation of the fungus from apple foliage. Controlled
laboratory studies were conducted to determine the conditions
necessary for foliar infection by S. sclerotiorum . Results
showed that not only would the fungus infect wounded leaves , but
that unwounded leaves developed lesions providing that continuous
moisture was present.

The life cycle of Sclerotinia sclerotiorum is well known on
beans, lettuce and many other vegetable crops. However, to date
no successful studies have been done on how the fungus infects
apples. It is presently believed that spores, released during
spring rains, infect blossoms. It is further thought that pro-
longed wet weather encourages the fungus to continue growth into
developing fruit with an end rot resulting. It is likely that
foliage infections occurred directly from spores, or following
contact with young fruit infected with S. sclerotiorum . It may
be possible that fungal spores are present on anthers or pollen
grains, thus, explaining many of the foliar infections described
above.

At this time, the fungus does not seem to present an economic
threat to apple foliage. However, end rots have been increasing
during the past 3 years (FRUIT NOTES 48 (1) : 10- 16) . Current apple
scab fungicide programs may not provide adequate control of calyx-
end rots and no fungicides are currently registered for the disease
When prolonged infection periods exist between pink and first
cover, applications of captan and benomyl may be helpful.

In attempts to gain more information about the disease on
apples, the Department of Plant Pathology hopes to monitor develop-
ment of Sclerotinia sclerotiorum under controlled conditions in the
field next season.

**********

-20-

USE OF PROMALIN TO INCREASE BRANCHING OF YOUNG TREES

Duane W. Greene
Department of Plant and Soil Sciences

Abbott Laboratories has been granted final label registration
for Promalin to improve branching on apple trees. There are sever-
al varieties and strains such as Macoun, Empire, Macspur and other
spur-types that branch sparsely, which limits their productive cap-
acity. Promalin*may increase lateral bud break and total shoot
growth per tree and improve branch angles on non-bearing trees.
Promalin may also reduce the potential return bloom for the season
following application. Therefore, Promalin is primarily recommended
for non-bearing trees to enhance early scaffold branch growth and
development and to provide a better tree framework.

Application Methods and Rates Suggested on Label

Foliar sprays . Use one-half (0.50) to one CI) pint of Promalin
per 5 gallons of spray solution to attain a concentration of 250
ppm of Promalin in the final spray solution. Wetting, spray cover-
age and subsequent absorption can be improved by the addition of a
wetting agent such as Buffer-X, Tween 20, or Glyodin. The wetting
agent should be added to the spray tank before Promalin. The final
spray should not be alkaline. If you have reason to suspect that
your water may be alkaline, then it may be advisable to add a buffer
such as Sorba Spray, vinegar or a buffered surfactant such as
Buffer-X.

Latex applications . Use one-third (0.33) pint of Promalin per one
(1) pint of interior flat latex paint to attain a concentration of
7500 ppm. Mix thoroughly. A buffered wetting agent such as Buffer-X
or Tween-20 should be added to the tank mix at a rate of 0.5 to 1.01
prior to the addition of the Promalin. This practice will improve
the solubility of Promalin in the latex paint and will also improve
wetting and absorption through the waxy layers on the bark surfaces.

Research in Massachusetts showed that sometimes too many branches
are stimulated following a Promalin application. This is especially
true when 500 ppm Promalin is used on very responsive varieties, such
as Macspur and Empire, at a time when growth is rapid and environmental
conditions favor foliar penetration. This situation can be overcome
by: 1) using lower rates of Promalin; 2) using the high rate of
Promalin, then returning about 3-4 weeks after application and remov-
ing the unwanted developing shoots.

Method of Application Suggested on Label

Foliar sprays . Uniformly apply the Promalin spray mixture with a
pressurized hand sprayer, hand gun attachment to an airblast sprayer,
or an airblast sprayer to thoroughly wet the bark and foliage sur-
faces. Do not apply to point of runoff. It is suggested that

Trade name

-21-

approximately five to ten (5-10) gallons of spray mixture will
treat an acre of non-bearing (1-5 year old) trees on a 12 x 12
spacing (310 trees). Spray volume should be adjusted to tree size
and density.

On small trees we have found a small (2-3 gal.) hand sprayer
very useful. Branching is stimulated only on portions of the tree
that are sprayed. The spray can be directed only to the areas of
the tree where branching is desired.

Latex applications . Uniformly apply the Promalin- latex mixture
with a brush or sponge to thoroughly cover the bark surface. Apply
only to one-year-old dormant branches.

Under Massachusetts conditions we believe that foliar sprays
should be the first choice of application. Foliar sprays are
easier to apply and may be more effective. The exception to this
might be during the first year the trees are in the ground.

Timing of Application

Foliar sprays . Application of Promalin should be made during the
period when there are from one (1) to three (3) inches of new ter-
minal shoot growth. This period generally coincides with a timing
of one (1) to two (2) weeks after full bloom. There are a few var-
ieties such as Spur Rome that can be stimulated to branch beyond
this period. Nursery stock should be treated after trees attain
a terminal height at which the first lateral scaffold branches are
desired (i.e., greater than 30 cm).

Latex applications . Since this treatment is intended primarily for
stimulating lateral growth from vegetative buds on one-year-old
dormant wood, applicaton of Promalin should be made in late April
and early May depending on season and locality. A useful guide is
to make the application just as the terminal buds on shoots or spurs
are beginning to break. Applications after lateral buds have broken
may cause some injury to the tender shoot tips and fail to promote
continued shoot growth from that point.

Application Considerations

Since Promalin is a plant growth regulator that must be absorbed
by the plant to be effective, best performance can be expected with
good absorption conditions. Furthermore, not all varieties respond
equally well to Promalin; Spur-type Mcintosh and Empire respond very
well, Delicious is intermediate and Northern Spy and Paulared are
almost unresponsive.

Do not treat trees of low vigor. Results will always be dis-
appointing. Promalin will not stimulate growth or branching on low-
vigor trees or trees suffering from drought, winter injury or low
fertility. Promalin is mot effective when used on healthy, vigorously

-22-

growing trees.

Promalin at the rates recommended can thin the crop the year
of application and prevent flower bud formation for the following
year. Therefore, whole tree treatments should be limited to young
non-bearing trees. However, a localized application on one-year-
old wood in either latex paint or by a directed spray may be done
without reducing flower bud formation on spurs. Localized appli-
cations would be useful to stimulate branches for a 2nd or 3rd
whorl of scaffold limbs or to stimulate branching on portions of
a limb.

Promalin is not effective in stimulating branching on limbs
with blind wood. Most branching that occurs following a Promalin
application results from stimulation of growth of healthy spurs
having a large leaf area or from large buds on 1-year- old-wood.

**********

Cooperative Extension Service
U. S. Department of Agriculture
University of Massachusetts
Amherst, MA 01003

Official Business

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FRUIT
NOTES

PREPARED BY
DEPARTMENT OF PLANT AND SOIL SCIENCES

COOPERATIVE EXTENSION SERVICE,
UNIVERSITY OF MASSACHUSETTS. UNITED
STATES DEPARTMENT OF AGRICULTURE AND
COUNTY EXTENSION SERVICES COOPERATING.

EDITORS
W. J. LORD AND W. J. BRAMLAGE

Vol.48 No. 3
SUMMER ISSUE, 1983

Table of Contents

Leaf Analysis Service and Standards
for Nutrient Levels

Gypsy Moth as a Pest of Highbush Blueberry
in Massachusetts

Marketing Your Fresh Fruits and Vegetables

NRAES-16 Planning Farm Shops

Why, When and How to Summer Prune
and Results to Expect

Extent of Damage by Major Apple Fruit
Injuring Insects in Massachusetts

Issued by the Cooperative Extension Service, Daniel I. Padberg, Director, in furtherance
of the Acts of May 8 and June 30. 1 91 4; United States Department of Agriculture and
County Extension Services cooperating. The Cooperative Extension Service offers equal
opportunity in prograrns and employment.

LEAF ANALYSIS SERVICE AND STANDARDS FOR NUTRIENT LEVELS

William J. Lord
Department of Plant and Soil Sciences

Leaf analysis is an effective guide to more economical and
efficient fertilizer practices; and as an aid in diagnosing
specific problems in individual orchards. The accuracy of
diagnosis depends upon accuracy of sample collection. Thus,
it is important that the procedures described below are followed.

The leaves are analyzed for nitrogen, potassium, phosphorous,
calcium, magnesium, manganese, iron, copper, boron, zinc and
sodium. Nutrient sprays of calcium, manganese, zinc, copper, and
boron leave residues which make analyses for these micronutrients
meainingless without carefully washing the leaves prior to wilt-
ing, to remove the residue. Washing procedures to remove this
residue require specific laboratory procedures which cannot be
provided by or compensated for by this service. Therefore,
leaves from trees sprayed with these micronutrients cannot be
used for micronutrient analyses.

Sampling Procedure

1. Sampling Individual Trees to Diagnose Problem. ( Leaves from
each tree constitute the sample . )

Select a minimum of 3 trees of the same variety in a block
showing the condition in question. Then as an aid in diag-
nosing, select a minimum of 2 trees of this variety not
showing the condition in question. Now sample each tree

separately the leaves from each tree will constitute a

sample. A leaf sample consists of: apple trees (50 leaves
per tree); peach tree (80 leaves per tree).

Analysis of leaves from individual trees in a block is more
expensive, but is more meaningful than a composite sample
from several trees .

2. Composite Sample to Diagnose Problem. ( Leaves from several
trees are combined into one sample ) .

Obtain 10 leaves from each of 5 or more trees of the same

variety in a block showing the condition in question and put

them together as one sample. Then, obtain a similar sample
from trees not showing the condition in question.

3. Composite Sample to Determine Genera] Nutritional Level.

( When no problem is apparent and the knowledjje of the general
nutritional level is desired . )

Select If) trees of the same variety which represent, as nearly
as possible, the general vigor and crop load of the block
being sampled. Collect 10 leaves from each tree to make up
a single sample.

Sampling Instructions

1. Collect all leaf samples between July 15 and August 15. Sample
when leaves are dry.

2. The leaf samples should be restricted to tlie healthy leaves
on trees suspected of being deficient of some nutrients. All
leaves should be free from insect, disease, or mechanical
injury. Be sure the trees are free of mouse injury .

3. Select all leaves from the middle of current terminal or
lateral shoots. Do not select spur leaves. Not more than
two (2) leaves should be taken from any one shoot. Sample
around the periphery of the tree at a mean height of five
feet from the ground.

4. Remove the leaves in such a way that the stem of the leaf
is attached.

5. Label or make a map so that the trees sampled can be located
at any time in the future. This will enable you to sample
the same tree in tow or three years to determine any change
in nutritional status as a result of a fertilizer program
adjustment .

6. Place the leaves in bag purchased from the SOIL AND PLANT
TESTING LABORATORY, 240 BEAVER STREET, WALTHAM, MA 02254.

Standards For Nutrient Levels

On the next 2 pages are our leaf analysis standards for nutrient
levels in: (1) young, non-bearing apple trees; (2) bearing apple
trees; and (3) peach trees. When using these standards as a guide
for fertilization, remember that the crop size on the trees at time
of sampling influences greatly the nutrient level of the leaves. For
example, leaves taken from an apple tree with a large crop may be
0.2 to 0.3% higher in N than when the same tree has a light crop.
The factors affecting nutrient content of the foliage and fruits of
apple trees were discussed in the winter 1982 issue of FRUIT NOTES
(Vol. 48).

Table 1. Leaf analysis standards for nutrient levels in young, non-bearing
apple trees.

Element

Ni t rogen (N)
Potassium (K)
Cal ci urn (Ca)
Magnesium (Mg)
Manganese (Mn)
Boron (B)
Copper (Cu)
Zinc (Zn)

Shortage
(Below)

2
Optimum

(Within)

Excess
(More than)

2.00%

2.00-2.50%

2.50%

1.00%

1.20-1.50%

1.50%

1.00%

1 .25-1.80%

0.20%

0.25-0.^40%

0.50%

20 ppm

25-75 ppm

75 ppm

25 ppm

35-50 ppm

80 ppm

A ppm

6-10 ppm

10 ppm

15 ppm

25-50 ppm

50 ppm

Shortage: Corrective measures needed.
2

Optimum: Applications should be continued as present rate or increased
to tree age.
3

Excess: Amount applied should be decreased or eliminated.
k

Don't be concerned about low B levels until trees begin to fruit.

Young trees, particularly those on weak size-control rootstocks, are

eas i ly i njured by B.

Table 2. Standards for nutrient levels in leaves for bearing apple trees.

E 1 emen t

Shortage
(Below)

Optimum

(Within)

Excess
(More than)

h
Nitrogen (N)

1.70%

1.80-2.00%

2.20%

Potassium (K)

1.00%

1.20-1.50%

1.50%

Calcium (Ca)

1.00%

1.25-1.80%

Magnesium (Mg)

0.20%

0.25-0.^0%

0.50%

Manganese (Mn)

20 ppm

25-75 ppm

75 ppm

Boron (B)

25 ppm

35-50 ppm

80 ppm

Copper (Cu)

A ppm

6-10 ppm

10 ppm

Zinc (Zn)

15 ppm

25-60 ppm

50 ppm

Shortage: Corrective measures needed,
2
Optimum: Applications should be continued at present rate or adjusted
according to anticipated crop size.

3
Excess: Amount applied should be decreased or eliminated.

N levels of 2.0-2.50% for non-bearing trees and trees of firm-fleshed
varieties (Empire, Spartan, Delicious, Idared, etc.) are satisfactory.
On Golden Delicious 1.70-1.80% is best.

-k-

Table 3. Standards for nutrient levels in peach leaves

Element

2
Shortage

(Less than)

Optimum
(Within)

Excess
(More than)

Nitrogen (N)

3.00%

3.00-3.50%

3.70%

Potassium (K)

1.25%

1.50-2.50%

2.50%

Calcium (Ca)

1 . 35%

1.35-1.50%

Magnesium (Mg)

0.25%

0.35-0.50%

0.50%

Boron (B)

Copper (Cu)

5 ppm

7-10 ppm

10 ppm

Manganese (Mn)

25 ppm

90-110 ppm

110 ppm

Zinc (Zn)

15 ppm

25-50 ppm

50 ppm

Young trees should mai<e about 18 inches of new terminal growth
annually; 12-15 inches are sufficient for mature trees.
2
Shortage: Corrective measures needed.

3
Optimum: Applications should be continued at present rate of adjusted
according to anticipated crop size.

k
Excess: Amount applied should be decreased or eliminated.

5
Peach trees are very sensitive to excessive B. According to Ernest Christ,
former Extension Specialist of Pomology at Rutgers University in New Jersey
fertilizer with 5 pounds of borax per ton is satisfactory for peaches.
No additional B is ever needed or added.

■5-

GYPSY MOTH AS A PEST OF HIGHBUSH BLUEBERRY IN MASSACHUSETTS '

Charles F. Brodel
Extension Entomologist
Cranberry Experiment Station
East Warehara, MA

Highbush blueberry, Vaccinium corymbosum L., is one of many
plant species occasionally used as food by the gypsy moth (GM) .
In most years, it escapes serious damage because GM larvae prefer
to feed on deciduous trees such as oak, willow, poplar, apple,
and certain types of birch. From 1979 to 1982, however, GM larvae
were numerous enough to defoliate millions of acres of deciduous
forest in the Northeast. Supplies of preferred foliage were ex-
hausted in many locations, forcing partly developed larvae to
seek non-preferred plants. Also, in the spring of each year,
countless newly hatched larvae were blown from treetops within
infested areas to previously uninfested sites.

As small fruits extension specialist, I wanted to learn what
impact these unusual GM outbreaks have had on the Mass. highbush
blueberry industry. At their annual meeting this past December,
members of the Mass. Cultivated Blueberry Growers' Assoc, willing-
ly filled out a questionnaire concerning their experiences with
GM during the last 4 years. The following report summarizes and
evaluates their responses.

The average highbush blueberry planting in southeastern Mas-
sachusetts occupies an area of 1.46 acres, ranging between '^ and
4 acres. Plantings are rather uniformly distributed, with 4 being
situated on or near Cape Cod, 5 in the New Bedford-Fall River
area, 5 in the Franklin-Holliston area, and 8 in the Brockton-
Plymouth area. The northwestern perimeter of the blueberry growing
region seems to be formed by a line of 4 plantings extending from
Dudley in the south to Carlisle in the north.

Of the growers who returned questionnaires, 37% reported hav-
ing no problem with GM from 1979 through 1982. In most cases.

Many thanks are extended to the members of the Mass. Cultivated
Blueberry Growers' Assoc, whose cooperative support made this
evaluation possible.

Mention of trade names does not constitute endorsement or recom-
mendation for use.

their plantings were located on the Cape or along the southern
coastal region. The remainder of growers experienced problems
with GM in 1 or more years.

None of the plantings was infested in 1979, and only 2
plantings were infested in 1980, a year in which 5.1 million
acres of forested land in the Northeast were defoliated by GM.
However, in 1981, 71% of the blueberry plantings infested during
a 4-year period experienced noticeable GM populations. The
problem continued in 1982, when 6 of 17 infested plantings had
sizable numbers of GM.

A common concern of growers is whether or not a planting
infested with GM one season is likely to be infested the fol-
lowing season. Questionnaire responses do not provide a clear-
cut answer. On one hand, 2 plantings infested with GM in 1980
were reinfested in 1981. On the other, only 1 of 12 plantings
infested in 1981 was reinfested in 1982. These observations
indicate that an answer should only be attempted for particular
plantings after the following questions have been considered.
Were areas around the planting treated with insecticides? Were
surrounding woodlands defoliated by mid to late June or was a
considerable amount of foliage left after GM feeding? Were GM
moths observed in the woodlands and/or planting in August?
Were egg masses observed in the woodlands or planting in the
fall?

Another matter often pondered is whether or not the pres-
ence and composition of woodlands around plantings influences
the likelihood of an infestation. Again, questionnaire res-
ponses do not enable a definite answer, but do provide a few
clues. Regarding borders, responses showed that 15 plantings
where GM was a problem had woodland on at least 1 side. Ten
plantings not infested by GM likewise were bordered on at least
1 side. Contrary tc popular belief, the directional relation-
ship of woodland to a planting had no apparent bearing on the
likelihood of infestation. Interestingly, 2 plantings not
bordered by woodland became infested with GM. It would seem,
then, that woodland borders do less to affect the probability of
an infestation than the presence or absence of GM in the general
locale of the blueberry planting.

The composition of adjoining woodland does not seem to mat-
ter either, given that GM has accepted the tree species as food
plants. In 15 of 17 infested plantings, woodlands consisted of
deciduous species only or a mixture of deciduous and coniferous
species. In 2 other plantings, however, infestations originated
from solid stands of conifers, food plants that are known to be
less favored by GM.

-7-

The actual damage done to plantings by the larvae was of
interest. Growers were asked to estimate the percentage of
blossoms lost when larvae consumed either blossoms or blossom
stems. A summary of responses is given in Table 1. These esti-
mates should be viewed as conservative because in many instances,
control measures were undertaken during the initial stages of
larval feeding. Clearly, GM reduced potential crops in 1981 and
1982 and temporarily superseded the blueberry maggot as the most
important insect pest of blueberry.

Table 1. Feeding damage by gypsy moth larvae in southeastern

Mass. blueberry plantings, 1980-1982.

Percent

flowers Number of plantings

consumed 1980 1981 1982

9-25 5 3

26-50 10

51-75 13

76-100 110

Insecticide usage ranks alongside damage as a leading indi-
cator of pest status. A glance at Table 2 should leave no doubt
about the impact GM feeding had on the minds of most blueberry
growers from 1980 through 1982, During that period, half of the
growers who applied insecticide used Sevin , 5 treated with for-
mulations of the bacterium. Bacillus thuringiensis , and 3 treated
with malathion. On average, 3 applications were made prior to
and during bloom by each grower, with 10 being the maximum number.
Opinions about the results of these applications were mixed
(Table 2). Dissatisfied growers lamented the insecticides' lack
of residual activity and the ineffectiveness of Dipel^ and Thuri-
cide^ against older GM larvae. Only positive opinions were re-
corded by lone users of methoxychlor, Guthion^, and Imidan^. A
planting deliberately left untreated despite damaging levels of
GM lost an estimated 75% of its flowers.

Insecticide applications during bloom are potentially harm-
ful to native and rented pollinators. New Jersey has overcome
the problem somewhat by obtaining a state local need registra-
tion for Dylox^, an insecticide reported to be less harmful to
pollinators than Sevin. The questionnaire alluded to this issue
by asking if additional insecticides are needed in Massachusetts
to control GM larvae during bloom . Ten growers responded posi-
tively, 10 were negative, and 7 had no opinion.

Table 2. Use and perceived efficacy of insecticides against
gypsy moth larvae by Mass. blueberry growers, 1980-

1982.

Opinion on efficacy
Pos . Neq. Unsure

No. of

Insecticide

growers

Sevin

Dipel/Thuricide

Malathion

Methoxychlor

Guthion

Imidan

1
2
1

1
1

2
3

In summary, GM has been the most important regional insect
pest on highbush blueberry during the last 2 years. It has in-
fested about 65% of the plantings in southeastern Massachusetts,
causing considerable loss of crop via cons\imption of flowers and
flower stems. It has compelled growers to apply insecticides an
average of 3 times per season to reduce losses. Its distribu-
tion and population levels in the region have not been predict-
able from year to year; however, the south coastal region seems
to have been least affected.

**********

MARKETING YOUR FRESH FRUITS AND VEGETABLES

Donald R. Marion
Department of Agricultural and Resource Economics

How would
fruits and vege
doing so might
There is no que
possibly the mo
fresh fruits an
result, growers
with a bit of c
good crops . Un
financially sue
themselves. Th

you like to increase your income from growing fresh
tables? If you would (and who wouldn't) the key to
very well lie in improving your marketing program,
stion that marketing is an important consideration.,
st important. The technical aspects of producing
d vegetables have become quite scientific. As a
are able to control most pests and diseases and,
ooperation from the weather, are able to produce
fortunately, it takes more than a good crop to be
cessful because the products often don't market
e old adage about a better mouse trap is a familiar

one, but not very useful in many cases today. Tf you only built
a better mouse trap, what very well might happen is that, instead
of the world beating a pathway to your door, the pathway could
grow full of weeds. The reason is competition. In most situations
in the U.S. there is not just one mouse trap builder per area,
but instead several, perhaps many. That means that buyers have
a choice to make and, if all the mouse traps are of reasonably
good quality, that choice may be based upon something other than
the quality of the mouse trap (e.g. , convenience of availability,
price, nature of customer service, etc.); that is marketing.

Mouse traps and fresh fruits and vegetables may have little
in common, but the basics of effective marketing programs for the
two products would be surprisingly similar.

Important as the topic of marketing is, it is difficult to
be very specific to a group of growers because there is usually
no single, best solution for all. Individual situations are enough
different to call for som.ewhat different marketing programs in
each case.

Many of the differences in the marketing programs of individual
growers are small or subtle, and might easily be overlooked - but
those fine differences are important. That "fine tuning" often
marks the difference between success and failure. As suggested
earlier, to be successful, each grower must be better than other
growers in some respect that consumers view as important; that is,
he must give customers some reason to come to his place of busi-
ness and buy his products, rather than to buy from another seller.
In marketing jargon, that is called a "differential advantage".
It is necessary because a business firm does not automatically get
some particular quota or amount of business just by its existence -
it has to be earned - over, and over and over again. The pres-
ident of a small food chain in Massachusetts says that doing busi-
ness with food shoppers is like a long romance - - you must romance
them, and romance them, and romance them -- continuously. A large
successful pick-your-own strawberry operator says you have to reach
out to customers; you can't sit back and wait for them to come
to you because of your superior product.

Furthermore, no individual seller can expect to attract all
types of buyers. Some seldom ever buy from roadside stands, some
never pick their own, and so on. It is important to identify and
focus your attention upon that set of shoppers that represents the
best potential market for you - - your "target market".

And so, a first recommendation might be -

1. Get to know your customers and those in your target group -
who they are and what their needs and preferences are -
and then extend your business toward them by trying to
meet those needs and preferences.

-10-

Marketinp success is largely a matter of attitude. Let
your customers see a positive attitude; make it clear that you
appreciate their business.

But simply rcacliing out to potential customers is not
enough - you must have something to offer. That "something"
should be a "good" product. Don't forget that a "good" product
is not limited to the physical product itself, but includes an
assortment of services that are involved in the sale of the
physical product. Some specific examples will help to illustrate
this point.

-have products available in reasonably abundant quantities
and of "good" condition. Incidentally, it is very important
to judge quality from the customer point of view. For
example, many shoppers think that a Mcintosh or Red Delicious
apple must be solid red to be of "good" quality, and that
tomatoes should be uniformly red and perfectly round, and
that "good" sweet corn must be bi-color. Growers, of
course know that those characteristics are not exactly-
necessary to a "good" product but, until customer attitudes
and preferences have changed, they will not be completely
satisfied unless those conditions are met.

-make sure your equipment and facilities used in selling the
product are clean and wel 1 -appearing .

-provide adequate supervision and orderly handling of cus-
tomers from the parking area to the checking out area.

-use signs generously to:

1. lay out policies and regulations

2. post prices, etc.

3. give directions to product locations, to the check-
out area, etc.

And remember, signs are one part of the image that a business
projects to customers; make certain that your signs represent
you well.

-in handling customers be sure to give the impression that you
really want to satisfy them with your product.

For pick-your-own operators there are some additional consider-
ations. Surveys of 'pick-your-own customers indicate that they
appreciate the availability of toilet facilities, that ready-picked
fruit and/or other crops for sale adds variety and convenience
that is appreciated by pickers, and a special area provided for
children (playground and/or picking area) will enable pickers with
children to be more relaxed, and will help to avoid conflicts witli

-11-

other pickers and damage to crops and plants.

And so, the second suggestion offered is -

2. Provide customers with a really "good" product (includ-
ing related services) -a product that will please them.

The third suggestion is -

3. Price realistically and with conviction . This means
a "fair" price - not too high and not too low - and
don't be timid about it. No matter how low prices might
be set, some customers would surely complain that they
are too high. Unfortunately, that is the nature of some
customers. But if, in fact, your prices are fair there
is no reason to feel apologetic or to "pussy foot" about
them. Quite the opposite; customers are more likely

to feel assured that prices are reasonable when sales
personnel are quite positive and forthright in talking
about them.

To do a good job of setting prices, a grower must know
his costs well, to know what price is necessary. Doing
so has become difficult in recent years, with herky- jerky
but generally rapid changes in operating costs. As a
result, a grower must work his records harder than ever
before to be certain of maintaining a financially healthy
position .

It is also important to keep abreast of market conditions
to have a sense for prices elsewhere in the market and, therefore,
what customers will consider to be a reasonable price. Probably
the most important prices to stay in touch with are those at the
wholesale market and at supermarkets in your area. Many growers
object to the suggestion of using supermarket prices as at least
part of the basis for setting their own. However, it is a super-
market that is the principal competitor for most growers who are
retailing, and because of frequent visits there, it is supermarket
prices that most shoppers are likely to be familiar with. Further-
more, using supermarket prices as a pricing guide does not necessar-
ily mean following them exactly.

Special mention should be made of the problem of pricing for
a "bumper crop". As background, a very brief lesson in the
economics of demand and supply would be helpful. For most agri-
cultural products, a relatively small change in the quantity avail-
able in the markets results in a relatively large change in market
prices. That is, a 10 percent decrease in the supply of a
particular commodity would result in a price increase of more than
10 percent, and vice-versa. In the jargon of economics, that
condition is referred to as a relatively inelastic demand . The

-12-

dcmand for most agricultural products is of that nature and that
is a major part of tlic reason that many of our farm programs,
used to support agricultural commodity prices, operate on the
basis of government purchase of surplus supplies. Removing a
relatively small quantity of a commodity from the marketing sys-
tem, results in a relatively larger increase in the market price
for that product.

For individual growers that means that prices usually would
have to fall by a fairly large amount to clear the market in times
of a modest increase in market supplies available. In other words,
price-cutting or price-wars must be quite severe for very large
crops to stimulate consumer buying enough to sell the entire crop.
Likewise, during those same times, selling less, by grading more
selectively or simply not taking the surplus to the market, would
have a relatively greater effect on the market price and, therefore,
would increase total revenue. Most growers have probably noticed
this effect in times of short crops resulting from adverse weather
conditions , etc.

Of course, for this result to occur, essentially all growers
must follow the same practice so that market supplies are, in
fact, reduced. Each grower must choose to follow such practices
independently and voluntarily, however, since agreements of this
nature among producers would be a voilation of antitrust laws.

Realistically there is not a single price, but instead, pro-
bably a narrow range of prices that could be used successfully.
Where in that range a grower sets his price is a matter of policy
and philosophy, and also a matter of long run plans. Some mar-
keters have a philosophy of taking all they can get - charging
"what the market will bear" - while others are content to get wh„^
they need. Obviously, if you plan to be in business for some time
it is important that your prices create a favorable image among
shoppers, but must also provide a reasonable profit (return- to-
your investment in the business) in addition to a satisfactory
wage for the time devoted to that part of the business.

Most growers perfer a single price for all customers. Cer-
tainly, that is a simple and straightforward policy and may help
to avoid hassles over who is entitled to a reduced price. Per-
sonally, I prefer a multiple-pricing system that offers customers
an incentive to buy larger quantities for preserving, especially
in times of large crops.

No matter how good your product, nor how attractive your
price, it will all go for naught if consumers don't know about it.
Advertise freely in newspapers and on radio - even TV for large

-13-

operations. Also explore .ill possible opportunities for free
publicity via press releases, feature articles, public service
broadcasts, etc. Some other suggestions that might bear con-
sideration are -

- consider preparing a "standing ad", that is ready to be
used, before the marketing season. During the harvest
period it is often difficult to find time to prepare an
ad, but that could be just what is needed during the time
of surplus supplies. Having an ad prepared in advance
might, under those circumstances, be very helpful.

- consider special promotions such as a strawberry festival,
a cherry pie baking contest, a corn roast, an apple festi-
val , etc.

- print up hand-out materials on the handling and preparation
of the commodities you sell, with recipes.

- use telephone recorded information on prices, hours of
business, etc. , when the volume of telephone inquiries is
high.

The fourth suggestion offered, then, is -

4 . Promote your business adequately

Recapping the suggestions offered -

- get to know your customers and extend your business to
them

- provide all customers with a "good" product

- set prices realistically and with conviction

- promote your business

To be sure, the preceding discussion is a brief and simpli-
fied treatment of the subject of marketing. Much has been omitted
and of the suggestions offered, most could be discussed in much
greater detail. However, it was not the intent of this article
to "dot all of the i's and cross all of the t's" with respect to
marketing, but rather, to briefly review some of the important
considerations for a successful marketing program. Serious atten-
tion to the suggestions offered should help most growers to develop
a more effective and, therefore, more profitable marketing program
for their operation.

14-

Lines

SPUR BLIGHT OF RASPBERRIES

Daniel R. Coolcy, C. M Becker^
and W. J. Manning

Department of Plant Pathology
University of Massachusetts, Amherst

Spur blight is a disease of raspberries caused by the fungus
Didymella applanata . The fungus infects buds, nodes and sometime:
the internodal regions of raspberry canes during the summer. The
disease surreptitiously depresses berry yields, for canes are seldom
Killed, yet some bearing nodes and transport tissue on each cane
may be destroyed. Serious epidemics can reduce yields by 30%,
though light infections may not depress yields at all. It is'also
thought that spur blight makes canes more susceptible to winter
injury .

Symptoms

Spur blight first appears on new canes, usually near the base,
m late spring or early summer. In Massachusetts, the first lesions
should appear in June. Brown or purplish soots develop around areas
where leaves are or were attached. These spots may enlarge to cover
the cane for 4 or 5 inches, but usually lesions are limited to an
area around the leaf petiole. These lesions turn to gray areas with
tiny black spots on the cane in the second (fruiting) year. Buds in
the affected area are weak, and some buds fail to develop at all.
Laterals in the area are weak and yellowed, and may wither and die.

The grey lesions are similar to those caused by another disease,
anthracnose. However, anthracnose has a characteristic bulls-eye
pattern of dark rings in the lesion. Spur blight lesions are more
scattered, and are almost always associated with leaf nodes.

Disease Cycle

The spur blight fungus produces two similar kinds of fruiting
bodies. These occur together on lesions. There are differences in
the length of time during which each type of fruiting body releases
spores. However, spores of one type or the other are present from
early spring to late fall.

One type of spore is called an ascospore, which is produced in
a fungal fruiting structure called a perithecium. Perithecia are
found in lesions on second year canes. The majority of ascospores
are released when new canes are emerging in April or May. The spores
are released largely during and after rain, though low levels may
be released by dew. Most ascospores are released by the end of
June. While these spores cause new infections on first year canes,
they do not cause all primary infections, and they are not the only
type of overwintering spore.

1 7 "5

Extension Technician "^Research Assistant Professor of Plant Patholog
The authors would like to thank Paula Saucier for the illustration,
and Dr. William Lord for advice on pruning techniques.

-15-

A second kind of spore is released over a larger part of the
growing season. These spores are called pycnospores and they are
borne in another type of fruiting body called a pycnidium. Pycnidia
appear as tiny black pustules in the old infections. As with the
ascospores, the pycnospores mature over the winter and are ready
for release during the next season. Pycnospores are mature and
may be released from March to October. However, the bulk of the
pycnospores appear to be released from June to mid-August. It is
during this period that most new infections occur, indicating the
importance of these spores in the disease process.

Once released, both types of spores are wind-carried to the
leaves and buds of canes. Senescent tissue is most susceptible.
One theory states that the lower leaves are preferentially infected
because they begin to senesce in June. The infection then travels
down the leaf stem and infects the node. Others feel that buds and
laterals in the lower part of the planting provide relatively moist
niches for fungus development.

Once the spores have germinated they infect and injure or kill
an area around the leaf petiole and its base. There is little in-
formation as to what stimulates pycnidial formation versus perithecial
formation. The fungus overwinters in the infected tissue producing
pycnidia and perithecia. The next spring these structures release
spores which infect new plants. The life cycle is shown in Figure 1.

Management

The first decision a grower should make is whether there is a
serious spur blight problem in a planting. As mentioned, serious
outbreaks can reduce yields by 301. If the problem is causing eco-
nomic damage, there are a number of steps which can help manage the
disease. When growing summer-bearing raspberries in the narrow
hedge-row system, cut out old canes immediately after harvest. Also
remove weak and diseased canes, and thin the rows. The rows sliould
be no more than 1 ft. wide at ground level. There should be about
25 canes growing in every 10 feet of row. Good weed control is
also essential for maintaining good aeration and spur blight control.

1. Insure proper ventilation in the planting. This is important
in managing other fungus diseases, particularly fruit and cane blight
( Botrytis ) and anthracnose ( Gloeosporium ) . Too dense a row inhibits
drying and spray penetration, and encourages fungal development.

2. Do not overfertilize, or push growth too fast. Raspberries
are a vigorous plant and respond well to fertilization. However,
too much growth causes dense foliage (see 1. above) and increases
senescence in the lower leaves. This increased number of senescent
leaves increases the number of places where infection can occur.
There is a practice which advocates applying a controlled amount

of contact herbicide to the first flush of cane growth in spring to
reduce overall growth and promote cane health through the rest of
the year. This practice is still experimental, but illustrates how

-16-

a slower growing raspberry plant will often have less disease pro-
hlems .

3. Apply fungicides at the correct intervals. Fungicides
(Table 1) are useful in reducing spur blight when applied as pro-
tectants during the growing season, and as eradicants on dormant
canes .

During the growing season, use captan or ferbam. Apply the
first spray when new canes first appear. Apply subsequent sprays
at 14 day intervals, up to 2 weeks before harvest. If rain is
particularly heavy, that is, in excess of two inches, it may be
necessary to reapply the fungicide before 14 days have elapsed.
This treatment usually requires 4 or 5 sprays in a season. The
most critical stage is at early bloom. A spray should be scheduled
at early bloom for maximum effect.

At bud swell, and when canes are dormant in late fall, a lime
sulfur treatment may be applied. Bordeaux (3-3-50) may be applied
when new canes are 8 to 12 inches high. These applications are
designed to kill the fungus in bearing canes.

Future Developments

Unfortunately, there are no raspberry varieties resistant to
spur blight. However, sources of resistance have been found, and
resistant varieties are being bred. Resistant varieties should
provide the best solution to spur blight problems.

Table 1. Fungicides for Spur Blight

Dormant and Early Spring

Fungicide Amt/100 gal Timing

Lime sulfur 1 to 4 gal No later than bud break

or
Bordeaux 6 lbs spray lime No later than 12 in. of

plus growth on new canes

6 lbs copper sulfate

Bud Break Through Harvest

Fungicide Amt/100 gal Timing

Captan 501 WP 2 lbs At 10-14 day intervals;

or maintain good coverage

Ferbam 761 WP 2 lbs especially at early bloom

Apply approximately 200 gal/acre in mature plantings. In small
plantings, spray until plant surfaces are throughly covered.

Figure

I'Lsen.sc cvcle of rasni-.errv utiir hli'-,l:t.

1 7-

From
spring through
summer mature
spores are released

CIDCHDt

During winter, spores develop in
infected tissue in plants Infected
canes are weakened

Spores land on
susceptible tissue and Invade
First symptoms are dark areas
in leaves

Purple lesions develop on the base of new canes,
especially around petioles, during sum mer

-18-

NRAi:S-16 PLANNING FARiM SHOPS

Rick Grant
nepartment of Food Engineering
University of Massachusetts

With equipment needing maintenance and various construction
and/or fabrication projects going on, every farm needs a good
and efficient farm shop. A good shop consists of work areas for
machinery, metal, repair, and woodworking along with a storage
area. So to have a good and efficient shop means careful planning.
Now careful planning means consideration of shop location on farm-
stead, type of structure, space requirements for each work area,
and locating tools near their respective work area. As each
area requires different tools, proper storage for easy accessibility
must, also, be taken into account.

Northeast Regional Agricultural Hnginerring Service (NRAES)
has published a new booklet entitled, "Planning Farm Shops".
In this booklet, NRAES very carefully covers various aspects in-
volved in designing the proper shop for the need. It contains
sections on building designs, utilities, space requirements, tool
and parts storage, equipment and tool specifications, shop safety,
plus an appendix on equipment templates. To elaborate more,
let's look into what each section has to consider.

Section one is on building design. Subjects covered in this
section deals with tlie fundamental components of the shop's struc-
ture as well as shop location and orientation. After locating the
shop, the type of building frame has to be chosen. Structural
materials to be used in construction has to be thoughtfully selected
especially in light of making the shop fire resistant. How well
insulated is the shop to be? What type of insulation should be
used? What type and how many doors and windows should there be?
What type of floor and should the possible use of a foundation be
considered? All these aspects must be carefully and thoughtfully
included in planning.

In the next section, the various utilities are discussed. After
a detailed floor plan has been laid forth, the different environmental
systems can then be intelligently planned in light of work area lo-
cations. Are enough electric circuits provided? Is the amperage
and voltage enough to run the equipment in each area? Is the light-
ing sufficient for each area? Is an adequate heating system installed?
If some type of plumbing is needed, is it sufficient to do the job?
How about ventilation? Has it been properly provided for? If a
hoist is to be installed, has the structural system been designed to
carry the load? All these utilities are vital to any shop and need
to be carefully incorporated into the design.

19-

When considerini: space requirements, three basic types of
work should be kept in mind. They are metal, engine and machinery,
and wood. Within these types of work are various pieces of
equipment. Kach piece of equipment has tliree space requirements
to consider. They arc the equipment itself, operator's space,
and workpiece space. So this section takes a look at planning
templates, template arrangement rules, and equipment and area
arrangement .

The next two sections deal with specifications of equipment
power hand tools, and hand tools. Suggestions are given as to
the quantity of tools and the capacity of various tools to cover
possible projects that may well be carried out in the shop. Guide-
lines for lists of hand tools are given for various areas of main-
tenance and construction.

A small one-page section on shop safety gives some pointers
in keeping the shop a safe place to work.

The appendix has templates of various pieces of equipment
which can be cut out and used in laying out the shop floor plan.
These are valuable aids in showing how large the shop must be for
the equipment to be placed in it. In addition, it allows for the
farmer to see exactly where electrical outlets, lighting, and
other environmental systems should be located to make the shop func-
tion properly.

As you can see, there is a lot to consider when planning a
farm shop. NRAES-16, "Planning Farm Shops" provides you with the
essentials you need when planning a shop for your farm. This book-
let may be obtained by writing to the Cooperative Plan Service, Agri-
cultural Engineering Building, University of Massachusetts, Amherst, MA. 01003.

There is a $2.00 charge for the publication. Make the check payable

to the Cooperative Extension Activity Fund.

20-

WHY, WHKN, AND HdW TO SUMMER PRUNI; AND RF.SIJLTS TO EXPECT

William .1. Lord and Duanc W. Greene
Depart men t of Plant and Soil Sciences

Last year we discussed the results of our summer pruning
experiments (FRUIT NOTES 47(3) :l-6, 1982). In the article below
we have answered the following questions about summer pruning:
(1) why, when and how; (2) what results to expect; and (3) advan-
tages and disadvantages.

Whj£. Recent results from England, South Africa, Europe, and
Massachusetts indicated that late summer pruning can restrict
growth, increase red color on fruit, increase leaf Ca, reduce
the incidence of bitter pit, increase fruit flesh Ca , and reduce
internal breakdown in storage. In England Preston pruned by the
established spur method. This involved the removal of strong
laterals not needed for new branches and shortening of weak ones
to 3 inches to induce spur formation. Laterals of medium vigor,
mainly on the tree periphery, were not pruned. Subsequently,
these were shortened to a spur, or removed when crowding occurred
or they became too large. Laterals from spur systems or induced
spurs were shortened to 1 inch. In Massachusetts, the trees were
summer pruned by removing all current season's shoots. Terblanche
et al. in South Africa removed all current season's growth of the
bearing units as well as excessive shoot growth. Only sufficient
shoots were left to serve as future bearing units. Utermark in
West Germany drastically reduced leaf area by removing growth
beyond the outermost fruiting spur on each branch.

The summer pruning techniques that enhanced fruit quality
seem severe and time consuming, and contradictory findings have
been reported. Thus, our experiments were designed to compare
effects of summer pruning with winter pruning and to evaluate
methods that fruit growers might adapt. The experiments were
established on young bearing trees of: (1) Mcintosh on seedling
roots; (2) Cortland on M7a; and C3) Red Prince Delicious on MM106
rootstock.

When and How to Summer Prune . August is the best time to summer
prune because of less regrowth than from earlier pruning. We
believe that the need to summer prune can be reduced with contain-
ment and corrective pruning during the winter to restrict tree
spread and height. The following procedures are suggested during
dormant pruning.

1. Branches that crowd those of adjacent trees will have to be
removed or cut back to a weaker side branch. (Cuts made only
to maintain the desired outer profile of the tree compounds
rather than alleviates tree containment problems, Such cuts will
produce vigorous growth which by the end of the next growing
season may extend as far as the original branch was before
shortening, and may cause more shading within the tree than did
the original uncut branch.)

-21-

2. Maintain conical tree shape by removing large limbs in the
top third of the tree or cutting back to a very much weaker
side branch.

.3. Initiate a limb rotation program in the top 1/3 of the tree
by retaining weak branches, spreading desirable watersprouts
which in turn may have to be removed when they become too
large.

4. Remove watersprouts which are not needed to protect branches
from sunscald or to provide for branch renewal. Those retained
for branch renewal generally require spreading.

5. Remove weak drooping branches which are severely shaded and
have few fruiting spurs.

6. Reduce the height of excessively tall trees by stubbing to

a strong outward growing lateral branch originating at a lower
level on the leader.

7. Frequently a strong scaffold branch with a narrow crotch angle
develops in the upper 1/3 of the tree. If this branch is not
removed or its growth restricted, the tree will become a
multiply leader tree. Trees of this type are much more diffi-
cult to prune when practicing containment pruning or lowering
tree height.

8. Delicious trees are subject to weak crotches, and branches are
prone to develop whorls and to droop. The ends of drooping
branches should be removed back to a lateral growing in a
somewhat upright position. This will shorten and stiffen the
branches. The tip of the lateral on a pruned drooping branch
should be higher from the ground than any other portion of the
branch. This should reduce the problem of suckering.

9. Cortland produce many small lateral branches. Detailed pruning
is required to reduce the number of these branches. Remove
slender hanging branches. Thin out the remaining branches on
each scaffold limb.

During August remove 1 to 3 year old wood that is causing shad-
ing. Concentrate efforts in the tree's periphery and particularly
in the upper crown area of the tree. Remove watersprouts, risers
and shorten drooping limbs that are too close to the ground. If
the trees have not been pruned well during dormant pruning, it
may be necessary to remove a few large limbs at their point of
origin on the trunk in the lower two-thirds of the tree canopy. Avoid
thinning or stubbing large branches in the top 1/3 of the tree.
When these branches fall they cause bruising and drop of some fruit
on the lower branches.

-22-

We have one grower in Massachusetts who has summer pruned
with a tractor-mounted sickle bar for the last 3 or 4 years.
He believes red color is increased on the hedged trees and that
the practice reduces the cost for winter pruning.

Resulte. We compared the effects on growth and fruit quality from
winter pruning and summer pruning. The fruit quality measurements
include fruit size, soluble solids (sugar content), fruit flesh
firmness, fruit flesh calcium content, and senescent breakdown
during storage.

The corrective winter pruning or corrective winter pruning-plus-
summer pruning procedures reduced the problem of tree crowding in
the block of Red Prince Delicious trees. However, corrective
winter pruning-plus - summer pruning in comparison to corrective
winter pruning had little or no effect on growth or fruit quality.

Summer pruning has been suggested as a technique for devital-
izing trees in crowded plantings. The overall growth of the Cort-
land trees, as indicated by trunk circumference increase, was
reduced by summer pruning. Nevertheless, terminal growth the year
following summer pruning was greater than on the dormant-pruned
trees. The Red Prince Delicious trees also were not devitalized
by summer pruning. The only consistent beneficial effect of summer
pruning was improved red color of Mcintosh apples from trees
receiving the dormant-type mechanical hedging, or the cutting to
the first fruiting spur summer pruning treatments.

Advantages of Summer Pruning

1. Increase red color development on some varieites.

2. Could provide work for employees experienced in pruning during
the slow season, in some orchards, prior to harvest.

3. Reduce the amount of pruning necessary during the winter months.

Disadvantages of Summer Pruning .

1. Finding the time to prune.

2. It may not reduce terminal growth the year after pruning which
is the primary cause of tree crowding.

3. In most cases, there may be either no effect of summer pruning

or the responses may not be consistent from year to year, or they
may be undesirable. Smaller fruits, lower soluble solids (sug.T
content) , more storage scald, bitter pit and cork spot are
examples of undesirable responses in our experiments.

-23-

4. Woolly apple aphids may colonize at the pTuninj; cuts.

5. Some regrowth may occur after summer pruning and leaf drop
is later on this wood. Delayed leaf drop is an indicator of
delayed maturity of wood, which increases the risk of winter
injury and has been one of the concerns with summer pruning.
Raymond Granger, CD. A. Research Station in Quebec reported
that summer pruning, among other factors, appeared to increase
severity of winter injury to apple trees during the winter of
1980-81.

6. The summer pruning practices of R.P. Marini and J. A. Barden
in Virginia reduced the amount of bloom on 2-year-old wood.

Cone lusions Majority of trees in Massachusetts are on vigorous-
size controlling rootstocks and the responses to summer pruning,
with the exception of improved red color, may be slow to develop.
Summer pruning can reduce the amount of pruning necessary during
the winter months and possibly improve work efficiency during
the summer. However, it is doubtful that summer pruning will
become a common practice except in a few situations of severe
tree crowding. Summer pruning will be mainly practiced for tree
training in non-bearing blocks and has the potential for improv-
ing fruit color in crowded bearing trees.

**********

EXTENT OF DAMAGE BY MAJOR APPLE FRUIT INJURING INSECTS

IN MASSACHUSETTS

R.J. Prokopy, W.M. Coli and G. Morin
Department of Entomology

Now that the 5-year (1978-1982) pilot integrated pest manage-
ment (IPM) program on apples has ended in Massachusetts, we take
the opportunity to present here a summarized account of insect
injury to fruit which we and the IPM field scouts encountered at
harvest in the various IPM and check commercial orchards that were
sampled .

The data in Table 1 have been reported previously as portions
of other articles in FRUIT NOTES [V.44(l), V. 44(6), V. 45(6), V. 47
(1); V. 48(1)]. They are offered here, in condensed form, to pro-
vide an overview of the major insects which directly injure apple
fruit in Massachusetts. They were obtained via on-tree surveys at

-24-

liarvest: 100 fruit per tree on 6-24 trees per block, depending
on block size. Each sampled fruit was examined carefully, and any
insect injury, no matter how slight, was recorded. The data in-
clude about 151,000 apples sampled over 5 years from 87 "good-
cooperator" I PM blocks and about 64,000 apples sampled over 5
years from 40 check blocks. Sampled I PM and check blocks were
scattered from east-central to west-central portions of the state.

The data show that total insect -caused fruit injury averaged
3.18% in the IPM blocks versus 3.80% in the check blocks. The 5
most injurious pests in the IPM blocks were, in decreasing order
of importance, tarnished plant bug, plum curculio, San Jose scale,
European apple sawfly, and apple maggot. Together, these 5 pests
accounted for 98% of all insect - inj ured fruit in IPM blocks.
These same 5 pests accounted for 95% of all insect - injured fruit
in the check blocks, with plant bug again being the most injurious.

Do all insect injuries detected on trees at harvest by field
scouts result in downgrading of fruit in the packing shed? To help
answer this question, we refer to a packout survey published in
FRUIT NOTES 46(3). This survey involved examination of about
400,000 apples by packing shed personnel and about 60,000 of the
culls by Glenn Morin. It was conducted in 16 Massachusetts packing
sheds on 1980-grown fruit. Some of the orchards and blocks sampled
in the packout study were the same as those sampled for on-tree
injury in 1980, but several were not. Although this lack of
direct correspondence of sampled blocks does not permit accurate
direct comparison of on-tree injury with packout injury, the
substantial number of orchard blocks and apples sampled by each
method may be suggestive.

The packout survey of 1980 fruit showed a total of 0.63% of
the fruit culled owing to insect injury, or about 15% as much as
the average of 3.9% insect injury from 1980 on-tree surveys in
IPM and check blocks combined. In the packout survey, the most
injurious insects, in decreasing order of importance, were tarnished
plant bug (0.23%), San Jose scale (0.21%), plum curculio (0.10%),
and European apple sawfly (0.07%). Together these 4 pests accounted
for 97% of all insect -culled fruit at the packing shed. These were
the same 4 pests found to be the most injurious in the on-tree sur-
vey. Apple maggot egglaying stings, difficult to see with the
unaided eye but indicative of probable infestation by larvae in
the fruit flesh, were very rarely detected in the packing shed,
even though this insect caused injury to an average of 0.12% of
tree-sampled fruit in 1980.

Together, these findings indicte that among insects which dir-
ectly attack apple fruit, Massachusetts researchers, extension per-
sonnel, and fruit gorwers should be concerned primarily with the
aforementioned 5 species. For the past several years, we and/or
Drs. R.W. Weires and W.H. Reissig of New York have been conducting
research on improved ways of monitoring and controlling plant bug,
scale, curculio, sawfly, and apple maggot. We hope that continued
research progress will result in decrease of future injury from
these pests.

-25-

Table 1. Percent insect - injured fruit in on-tree surveys conducted
in integrated pest management (IPM) and check orchards, 1978-1982

Damaging insect

injured

fruit in^'^-

Avg.
inj ur

1978

1979

198

1981

1982

ed fruit

IPM

blocks

Tarnished plant bug

1.60

2.74

1.44

1.25

1 .12

.63

Plum curculio

.17

.39

1.19

.61

.43

.56

San Jose scale

.03

.33

.72

.27

.84

.44

European sawfly

.68

.03

.24

.16

.87

.40

Apple maggot

.13

.12

.10

.05

.01

.08

Leafroller

.01

.02

.05

.02

Fruitworms

.02

.01

Codling moth

.01

.04

.01

Other

.01

.11

.01

.03

Totals

2.64

3.64

3.76
Check

2.50
blocks

3.31

.18

Tarnished plant bug

2.33

3.10

1.44

1.20

.83

.78

Plum curculio

.17

.87

.47

.26

.59

San Jose scale

.96

1.07

1.43

.23

1.86

.11

European sawfly

.54

.04

.11

.02

.47

.24

Apple maggot

.08

.23

.14

.01

.09

Leafroller

.05

.04

.03

.01

.04

.03

Fruitworms

.59

.07

.03

.01

.15

Codling moth

.01

Other
Totals

4.72

4.73

4.09

.04
2.01

3.47

.01
.80

z
Number of blocks sampled: IPM - 1978(8), 1979(16), 1980(18),
1981(20), 1982(25). Check- 1978(8), 1979(9), 1980(9), 1981(7),

and 1982 (7) .

Number of fruits sampled: IPM - 1978(16,000), 1979 (32,000),
1980 (20,000), 1981 (30,000), 1982 (33,000); Check - 1978(16,000)
1979(18,000), 1980 (10,000), 1981 (11,000) and 1982 (9,000).

FRUIT
NOTES

PREPARED BY
DEPARTMENT OF PLANT AND SOIL SCIENCES

COOPERATIVE EXTENSION SERVICE,
UNIVERSITY OF MASSACHUSETTS, UNITED
STATES DEPARTMENT OF AGRICULTURE AND
COUNTY EXTENSION SERVICES COOPERATING.

EDITORS
W. J. LORD AND W. J. BRAMLAGE

Vol. 48, No. 4
FALL ISSUE, 1983

Table of Contents:

Cycling Fans in Apple Cold Storage Rooms
Can Be a Good Way to Conserve Energy

Effects of Mineral Nutrition on Keeping Quality
of Massachusetts Mcintosh: Results of a
Four-Year Survey

The Apple Markets from 1967 through 1982,
Locally and Nationally

Cider Notes

Pomological Paragraph: What Are Genetic Dwarfs?

The Starch Test Guide for Apple Maturity

Pomological Paragraph: Storage Temperature
for Mcintosh in CA

Postharvest Calcium Chloride Treatment

Acid Rain Affects Apple Maggot Fly Egglaying

New Publications Available

FRUIT NOTES Index for 1983

issued by the Cooperative Extension Service in furtherance

of the Acts of May 8 and June 30, 1914; United States Department of Agriculture and
County Extension Services cooperating. The Cooperative Extension Service offers equal
opportunity in programs and employment.

FRUIT NOTES SUBSCRIPTION

The Fall issue of FRUIT NOTES is the 4th and last issue for the
year. Now is the time to renew your subscription for 1984. The
question has been asked about multi-year subscriptions. This
would be desirable but the Editor of FRUIT NOTES retires in 1985
and the fate of this publication after this date is unknown.

To subscribe to FRUIT NOTES complete and mail the following form
with your check for $3.00. (Canadian subscribers please send a
U.S. postal money order.)

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Editor, FRUIT NOTES

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Make checks payable to: FRUIT NOTES ACTIVITY ACCOUNT.

Send subscription form and check to:

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University of Massachusetts

Amherst, MA 01003

CYCLING FANS IN APPLE COLD STORAGE ROOMS
CAN BE GOOD WAY TO CONSERVE ENERGY*

Gilbert E. Yost
Agricultural Engineer
USDA-ARS, Tree Fruit Research Laboratory
Wenatchee, WA

Energy used to operate fans in 'Red and Golden Delicious'
apple cold storage rooms could be cut nearly in half by using
a fan cycling scheme.

Refrigerated storage of apples in the Pacific Northwest re-
quires a large amount of electrical energy. Cost of electrical
energy has increased rapidly and future trends indicate it will
go higher.

USDA's Agricultural Research Service and the fruit industry
are looking for ways to reduce electrical energy input to save
energy and reduce costs.

Fans and refrigeration must run continuously in storage rooms
from harvest until the field heat is removed from the apples and
proper storage temperature is attained. At this point in time,
cycling fans and refrigeration could still maintain proper fruit
temperatures and save energy (Fig. 1). Fans cycled half of the
time use 52 to 601 of the energy used to run them continuously.

Five years of monitoring different fan cycling schemes such
as 12-hours on, 12-hours off; 6-hQurs on, 6-hours off; 8-hours on,
16-hours off; and 16-hours on, 8-hours off, in storages ranging
from "antiquated rooms to those featuring the latest state-of-the-
art in construction and equipment", show that "over all" the 6-
hours on, 6-hours off seems to be the best scheme.

Cycling 6-hours on, 6-hours off fits well with storage manage-
ment. This scheme compensated for the outside air temperature
fluctuations in the fall and spring and maintained the proper
average fruit temperature in different rooms in which it was tested

The cycling scheme could be scheduled around "peak load" hours
of the local utility company (some utility companies have a special
rate for customers that do not use power during these times) and
this adjustment would not interfere with the maintenance of the
fruit temperature.

This article appeared in the January 15, 1983 issue of the GoodFruit
Grower. Reprinted by permission of the author.

In a 1000-bin (800 pounds per bin) room held at 30-32°F
there are 800,000 pounds or 400 tons of apples. According to
"Modern Refrigeration and Air Conditioning" by Althouse, Turn-
quist and Braccinao, the heat of respiration of a ton of apples
at 32 F is 700 BTU's in 24 hours and 1/3 horsepower fan motors
give off 4250 BTU's per horsepower per hour.

Assuming this room contains twelve fan motors, the heat
produced by the motors would be 408,000 BTU's in 24 hours while
the heat of respiration would be only 280,000 BTU's for the same
time period. There would be 1.45 times more heat produced by
the fan motors than by the heat of respiration from the apples.
There are other factors involved but this example illustrates
one of the major areas for energy cost savings.

On-going research at the USDA Tree Fruit Research Laboratory
in Wenatchee, Washington includes monitoring and recording of
'Red and Golden Delicious' fruit temperatures during commerical
regular and CA apple storage rooms. The data collected over a
five year period showed:

(1) once a room was loaded with bins of apples the air pattern
established at the time remained the same throughout the
storage season.

(2) average fruit temperatures were maintained between 31-32 F
in cold rooms tested when the fans were run continuously
1/3, 1/2, and 2/3 of the time (by maintaining the fruit
temperatures, adjusting the cycling time to compensate

for the physical conditions of the room, and maintaining
proper fruit temperatures, the most efficient cycle time
can be established) .

(3) there was a fruit temperature gradient from the coldest
to the warmest sensored apple of 3-4 F;

(4) in rooms where the coils were located above the bins,
with air being blown out over the bins and filtering down
through the fruit and bins and then pulled back through
the stacks of bins to the coils, the apples in the top
bins were the coldest;

(5) the fans and refrigeration could be off up to 36 hours
before average fruit temperature rose 1 F (this could
vary depending upon the physical condition of the rooms) ;

(6) data from fruit quality evaluation tests indicted no signi-
ficant difference was detected between apples held in
noncycled rooms over the cycled rooms (however, during
periods of extreme cold weather (0 to -10 F or colder)
for several weeks it would be a wise practice to run the
fans continuously to restore some of the heat being lost
from the room to the outside atmosphere.

-3-

Most apple storages use cold room air temperature readings as
a guide to apple temperatures, but these do not give a true pic-
ture during storage.

Many cold storage rooms hold over a quarter-million dollars
worth o£ apples, and whether or not the rooms are cycled, both
air and apple temperatures should be monitored.

A system to do this c
probed for temperature mo
each bin, and put bins in
across the back, three ac
o£ the room; (2) use at 1
front of the coils and on
flow of the room; (3) con
ing device that automatic
four times every 24 hours
for "back-up" temperature

ould be to (1) use n
nitoring placed abou

the top layer of th
ross the middle and
east two air tempera
e behind the coils o
nect all air and fru
ally prints out temp
; and (4) use severa

readings in case of

ine bins with an apple
t 6-inches deep in
e stack of bins, three
three across the front
ture probes, one in
r in the return air
it probes to a record-
eratures at least
1 regular thermometers
electronic failure.

This type of cold room instrumentation can give management a
better insight on which to base their storage operation decisions
for each type of cold room.

Fan and refrigeration cycling will work. It will save energy,
lower energy costs and still maintain optimum apple temperatures
during storage.

Editors note - The author would like to express his thanks to the Washington
State Tree Fruit Research Commission, Tree Top, Inc., Pacific Power and Light
Company, City of Cashmere Light Department, Blue Star Growers, Snokist Growers,
Skookum, Inc., Stemilt Growers and to the personnel of the USDA-ARS, Tree Fruit
Research Laboratory for their cooperation in this study.

KWH
X 1000

150 -

100

SEPT. OCT.

— I 1 —

NOV. DEC.

JAN.

79-80

81 82

Figure 1. This chart
shows the amount of
energy used in a six-room
apple storage facility for
three seasons. After the
initial fruit cool-down per-
iod the fans and refrigera-
tion were cycled at 6-hours
on, 6-hours off during the
1981-82 season. During the
months of November, December
and January of the 1981-82
season a savings of approx-
imately 100,000 KWH over the
same months of the 1980-81
seasons was evident. This
would amount to a $1000 sav-
ings if the power rate was
one cent per KWH.

Figure 1,

•4-

EFFECTS OF MINERAL NUTRITION ON KEEPING QUALITY
OF MASSACHUSETTS McINTOSH: RESULTS OF A FOUR-YEAR SURVEY

W.J. Bramlage, M. Drake, S,A. Weis, and C.A. Marmo
Department of Plant and Soil Sciences

During the past 4 years we have been sampling commercial Mc-
intosh orchards in Massachusetts and comparing the mineral con-
centrations in fruit at harvest with their keeping quality after
storage. Full details of the procedures and of the results with
apples from regular air storage have been published in the Proceed-
ings of the 1983 Massachusetts Fruit Growers' Association, Inc.
Annual Meeting; only the thrust of those findings will be presented
here .

Between 1979 and 1982, a total of 172 orchard blocks of Mc-
intosh were sampled. Samples came from 6 counties in Massachusetts.
Fruit samples for analyses were taken 2 weeks before harvest, and at
the start of commercial harvest 2 bushels of fruit were taken from
each block. These 2 bushels were stored at the Horticultural Research
Center in Belchertown, 1 bushel at 32°F in air storage, and 1 bushel
in CA storage. Only results for air storage are reported here.

The air-stored fruit were removed in late January or early Feb-
ruary and placed at 70-80 F. After 1 day they were tested for firm-
ness and after 1 week they were examined for the occurrences of break-
down, scald, rot and bitter pit. Bitter pit was so infrequent that
data for it have been omitted. The average Ca and Mg concentrations
were quite uniform across the 4 years, and the concentrations of K
and P were only slightly more variable (Table 1). The concentrations
of N changed dramatically, however, falling by nearly 50% between
1979 and 1981. The cause of this decline is not known, but no com-
parable reduction of leaf N has been observed during this period.

The ranges of mineral concentrations among orchards are also
shown in Table 1. For Ca , in each year there were very broad ranges,
with some samples containing twice as much Ca as other samples. Many
of these orchards used calcium chloride foliar sprays during this
period, which likely contributed to this wide range. For K, P and
N there were approximately 50% ranges, i.e., some samples contained
50% more of the element than other samples. For Mg , less than
a 50% range existed in all years but 1980. Thus, Ca was the most
variable element in fruit from these orchards.

-5-

Table 1. Averages and ranges of concentrations of 5 minerals
(ppm, dry wt . basis, outer cortex tissue) in Mcintosh apples
from commercial orchards in Massachusetts, 1979-1982.

Mineral

1979^

1980

1981

1982

Average

145

153

145

152

4909

5459

5300

5100

360

438

358

392

243

283

256

262

2665

2227
Range

1500

103-183

101-240

110-252

105-208

3880-6110

4200-6750

4000-6400

4000-6000

291-444

335-551

288-482

343-460

214-278

241-367

216-288

222-310

2300-3300

1700-2900

1000-1800

1250-1870

z
Numbers of samples: 1979 = 34; 1980 = 49; 1981 = 41
1982 = 48.

Relationships between mineral concentrations in fruit at
harvest and the occurrences of breakdown, scald, and rot after
storage are illustrated in Table 2. For each element, 4 groups
of samples were established at arbitrary points within the
range for that element, in order to demonstrate the patterns of
relationships that appeared to exist.

Samples with increasing Ca concentrations developed de-
creasing amounts of breakdown after storage. In addition, with
increasing Ca concentrations, the frequencies of scald and of
rot also seemed to decline, though to a lesser extent than did
the amount of breakdown.

Most of the orchards sampled produced fruit with moderate
concentrations of K, but a few samples were relatively high in
this element. These high-K samples appeared to develop slightly
more breakdown and substantially more scald and rot than the rest
of the samples, but statistical analyses showed that due to large
variations within these groupings, only the effect on scald was
real.

As with K, most orchards produced fruit containing moderate
concentrations of P. However, a few samples had relatively low
P, and statistical analyses showed that these samples developed
relatively large amounts of breakdown and rot. For Mg , a few

-6-

Table 2. Relationships between concentrations of 5 minerals
in Mcintosh apples, and the occurrences of internal break
down, scald, and rot in samples from Massachusetts orcharc
after storage in 32°F air for 5 months followed by 1 week
at 75°F. . 1979-1982.

Ppm, dry
wt .basis

Number of
samples

Breakdown

Scald

Rot
(I)

Calcium

Less than

126

126-150

151-164

Greater th

164

7
Potassium

Less than

4750

4750-5200

5201-5800

Greater th

5800

21
Phosphorus

Less than

325

325-400

401-450

Greater th

450

7
Magnesium

Less than

241

241-270

271-300

Greater th

300

7
Nitrogen

Less than

1500 45

1500-2000 57

2001-2500 42
Greater than

2500 27

19
16
12

51
43
50

9
6
6

7
7
6

9
5
9

7
7
9

samples contained relatively high concentrations, and these
samples developed relatively small amounts of breakdown and rot,
although the effect on rot was not evident in the averages on
Table 2 due to the presence of a couple of high-rot samples in
this group. There was also a significant relationship between
N concentration in fruit and the occurrence of breakdown, with
higher N being associated with lower frequency of breakdown.

Fruit firmness is a crucially important quality character-
istic for apples, especially Mcintosh. It is therefore import-
ant to know if mineral composition of the fruit affected firmness.
There was no significant relationship between any of these elements
and fruit firmness, either at harvest or after storage. Thus,
differences in fruit firmness among these orchards could not be
attributed to differences in their mineral composition.

In 1980 and 1981, 5 micronutrients within the fruit were
also surveyed: boron (B) , zinc (Zn) , manganese (Mn) , iron (Fe)
and aluminum (Al) . The relationships between their concentrations
in fruit andquality of the apples after storage were generally
quite low. The strongest relationship was between low B and
increased breakdown in 1981 (though not in 1980) , but this effect
was much less than that of low Ca on breakdown.

The 4-year time period and the wide geographical distribution
of the orchards sampled in this survey produce an excellent view
of the effects of fruit mineral composition on the storage life
of Massachusetts Mcintosh apples. These findings indicate to
us that inadequate Ca in fruits is the primary nutritional factor
influencing quality of Mcintosh apples in Massachusetts, and that
this factor is expressed mostly in the occurrence of breakdown
after storage. Although excessive N and K in the fruit can cause
severe reduction in fruit quality, very few samples in our survey
appeared to be excessively high in these elements. Few samples
contained Mg concentrations that appeared to impair fruit quality,
and while low P did seem to be detrimental, only a small number
of samples contained detrimentally low P concentrations.

The relationship between low Ca and occurrence of breakdown
is further illustrated in Figure 1, where post-storage breakdown
in each of the 172 samples was plotted against its Ca concentration.
Regardless of their concentrations of other elements, samples
very low in Ca (e.g., less than 130 ppm) almost invariably developed
more than 10% breakdown, which we consider to be unacceptable
quality. In contrast, samples high in Ca (e.g., more than 175 ppm)
almost never developed lO";; breakdown. At intermediate Ca concen-
trations, it appeared that the fruit were susceptible to break-
down but whether or not it developed was determined by other
factors, one of which may have been the concentration of another
element. It appears that when Ca concentration was high, the

> -8-

apples were resistant to breakdown regardless of the concentrations
of other elements.

100

o
o

<
z

UJ
O

tr.

UJ
Q.

r • -.401

• • • » staff i\*»|^.»«* • •

100 130 160 190 " 250

ppm CALCIUM, OUTER CORTEX TISSUE

Figure 1. Scattergram showing percent breakdown after air storage
in relation to the Ca concentration in fruit at harvest
for each of the 172 commercial samples surveyed, 1979-
1982.

Our study reaffirms the importance of establishing adequate Ca
concentrations in Mcintosh apples if they are to be stored for long
intervals. There are 2 feasible approaches to this: foliar and post-
harvest applications of Ca. Application of a total of approximately
75 lbs. of CaCl2 per acre during the growing season can raise fruit
Ca concentrations by about 50 ppm, and a postharvest dip in 4% CaCl2
can increase it by about 35 ppm. It is evident that many commercial
samples did not contain adequate Ca concentrations and that they would
have benefited from the above treatments.

The
are rest
and rot.
after st
inf luenc
ly soft
and soft
storage
harveste
temperat
exhibit
position
manageme

effe
ricte
Pro
orage
ed by
fruit
ening
manag
d ove
ure o
infer
s doe
nt.

cts of m
d to the
bably th
is the
variati
is unac
of the
ement .
rmature,
r at the
ior qual
s not re

ineral nutrition

occurrence of d

e most significa

firmness of the

ons of any of th

ceptable, whethe

fruit is control

Regardless of th

cooled improper

wrong atmospher

ity after storag

duce the need fo

on apple quality recorded here
isorders (breakdown and scald)
nt attribute of Mcintosh quality
fruit, and fruit firmness was not
e minerals surveyed. An excessive
r or not it develops disorders,
led primarily by harvest and
eir mineral concentrations, apples
ly, or stored at too high a
ic composition are likely to
e. The best of mineral com-
r careful harvest and storage

THE APPLE MARKETS FROM 1967 THROUGH 1982, LOCALLY AND NATIONALLY

William J. Lord
Department of Plant and Soil Sciences

We have summarized yearly since 1967 the apple production in
the United States and in Massachusetts, and the F.O.B. prices at
Country Shipping Points in Massachusetts for 120 counts, U.S.
Fancy or better Mcintosh apples^. This information, which is pre-
sented in Table 1, indicates some of the factors that affect the
profitability of a marketing season.

Marketing Seasons

1967-68 and 1968-69 . Nationally these were "short" crop
years and prices for Massachusetts grown apples were good. The
fruit were in good condition and the demand for CA Mcintosh was
strong.

1969-70 . The national crop was the second largest in 30
years'^ This contributed to lower wholesale prices for Massachusetts-
grown apples than for the 2 preceding marketing seasons. Apple
growers in the western states of the U.S. produced about 17 million
more bushels in 1969 than in 1968 but received $41 million less
for their crop2. In Massachusetts, "Soft Mcintosh Problem" was
encountered after CA storage and wholesale prices remained low for
the entire season.

1970-71 . The hot summer and fall reduced fruit quality in New
England, Appalachia and Hudson Valley and many growers had low pack-
outs because of poor fruit color and condition. In Massachusetts
the returns for the large sizes of Delicious were better than in
1969-70 and prices for CA Mcintosh finished strong.

1971-72 . The 3rd consecutive national crop greater than 50
million was produced. U.S. growers asked the Secretary of Agri-
culture to appoint a team to study the marketing problems of the
apple industry because of low net returns during these years. (A
report of the team's findings with their recommendations as to
needed action was published in 1972. The team did an excellent
job of identifying the marketing problems of the apple industry,
most of which still persist.)

Slow color development in Massachusetts delayed the harvest
and marketing season and resulted in the harvest of too many large,
soft, poorly colored apples. Massachusetts growers harvested

Taken from the Special Apple Market Report published by the Division
of Markets, 100 Cambridge St., Boston, MA.
2
The Good Fruit Grower, Sept. 15, 1970.

10-

through the entire month o£ October. Prices for Mcintosh apples
from regular storage averaged only slightly higher than in 1970-71
and most growers lost money on bagged apples. During May and June,
1972, some Massachusetts growers again encountered the "soft
Mcintosh Problem". Low prices for CA-Mclntosh through the remainder
of the marketing season reflected the market concern about fruit
softness ,

1972- 75 . A small crop was harvested in Massachusetts and in
the U.S. as a whole. Prices in Massachusetts were $0.75 to $1.00
higher for regular storage Mcintosh than during the previous year.
Stored Mcintosh kept exceptionally well, no soft Mcintosh were
encountered and prices reflected this quality.

1973- 74 . The U.S. apple production was higher than in 1972
but the New England apple crop was the smallest since 1956 because
of frost and poor pollination weather. Massachusetts experienced
extremely hot weather from August 27 through September 4, 1973
and fruit probably softened rapidly. After September 4, the weather
became favorable for color development.

Due to a short Mcintosh crop, a light crop in eastern U.S.,
and an increasing demand for juice and sauce, prices were very
favorable for apples from regular storage. Most growers made money
on their bagged apples, which is not a common occurrence.

In early March of 1974, some storage operators again encoun-
tered soft Mcintosh, especially with larger sizes. Although the
problem was not as serious as other years the market reflected its
concern.

1974-75 . The national crop again exceeded 150 million bushels
and in New England it was 30% larger than in 1973. Mcintosh apples
in Massachusetts were smaller than usual, but the harvest season
was favorable for good color development.

Prices for regular storage Mcintosh were only slightly higher
than during the previous season. The prices for bagged and juice
apples were lower than in 1973, and those for CA Mcintosh reflected
the sof t-McIntosh problem encountered the previous year. Mean-
while, production and marketing costs increased drastically because
of the energy crisis.

1975-76 . The national crop was a record 178 million bushels
with 52 million from Washington alone. The early crop forecast for
New England was a 15% increase from 1974. However, rains delayed
harvest and drop was excessive in some orchards. Consequently,
storage holdings in Massachusetts were less than the previous season.

Prices for 120 counts were $0.75 to $1.00 less than during the
previous season for regular storage Mcintosh and somewhat less for

11-

those from CA storage. Consequently, growers who sold mainly
wholesale lost money.

New York and Washington growers also had no profit from the
record apple crop of 1975. New York had its largest apple crop
in 50 years, but apples were left unpicked because of heavy carry-
over of processed apples, the bumper crop, and financial problems
of processing plants.

1976-77 . The national crop decreased to 154 million bushels,
but in Massachusetts it was somewhat larger than during the previous
year. Prices for both regular and CA storage Mcintosh in Massa-
chusetts were very favorable throughout the 1976-77 marketing sea-
son. No soft Mcintosh were encountered and prices of those from
CA reached $11.00 in May and June.

1977-78 . A national crop in excess of 160 million bushels
was harvested. The New England crop was up 101 over 1976. In
Massachusetts frost reduced the Delicious crop. Wholesale prices
in Massachusetts were about the same as in 1976 for regular storage
Mcintosh but a strong demand for CA apples pushed prices higher
later in the season.

The 1977-78 marketing season was the 2nd consecutive profitable
year for most Massachusetts growers. The market for apples con-
tinued to improve during the late 1970 's because of increased
demand for fresh fruit and a growing demand for apple juice and
cider .

1978-79 . The national crop was about 101 higher than in 1978
with the increase being greater in the eastern and central states
than in the western states. Harvest in Massachusetts was 10-14
days later than in 1977. However, weather during harvest was ideal
with warm days and cool nights and no rain.

Marketing started about 10 days later than usual in Massachusetts,
but movement was good and the prices received were higher than dur-
ing the previous marketing season.

1979-80 . Massachusetts crop was down about 101, whereas the
national crop was larger. Some drop of Mcintosh was experienced in
late-August but weather became cooler and drop was not troublesome
thereafter. Many growers had an "umbrella" crop of Mcintosh, thus
they harvested many less fruits than originally anticipated.

Apple prices remained at the same level as in 1978-79. How-
ever, no soft Mcintosh were encountered from CA storage and the
price for these apples in April and May finished strong.

Nationally, this was the 4th consecutive large national crop
marketed without encountering the burden of over supply. One

12-

reason these large crops were manageable was the strengthening of
the export market. Market opportunities developed in the Middle
East, Latin America, and the Far East. In 1979-80, U.S. apple
exports reached 12.4 million bushels. In the 1960's the U.S. was
exporting only about 2 million bushels, with Canada taking close
to half of those.

1 980-81 . The U.S. apple industry encountered an oversupply
due to a national crop in excess of 210 million bushels. However,
the crop size in Massachusetts was similar to that of the previous
year. The harvested fruit was small in some Massachusetts orchards
due to dry weather. The season was 10-14 days late but rain did
not interfere with harvest.

Apple prices were quite favorable for 120 count Mcintosh in
September (approximately $11.00) but they declined to about $9.00
by early December. Basically, the poor movement and decline in
prices was caused by the supply pressure from Michigan and Washing-
ton. The prices for 120 counts increased $0.50 with the opening
of CA storages but remained at this level for the remainder of
the marketing season.

1981-82 . It was estimated that the New England apple crop
would be 201 less than in 1980. Massachusetts experienced a
freeze on April 22 and most orchards had poor pollinating weather
at bloom. Thus, few orchardists had a large crop.

New York state apple crop decreased from 26 million in 1980
to about 19 million in 1981. Production also decreased in Mich-
igan, Ohio, and Pennsylvania.

Prices for U.S. Extra Fancy Mcintosh 120 count started at
$11.00 in September, increased to $12.25 in October and $13.25
in December. Mcintosh were scarce in April and CA Mcintosh fin-
ished in middle May at $14.75 for 120 counts.

The large Washington state crop and small fruit size hurt
the New England's bagged Delicious market. The Washington crop
suppressed sales in the 1982 crop of Paulared.

1982-85 . Less apples were harvested than anticipated because
of the presence of small, seedless fruits on trees in many Massa-
chusetts orchards. Fruit color developed rapidly in late August
and Friday prior to Labor Day (Sept. 3) some growers picked Mcin-
tosh apples for CA storage. Unfortunately, color developed slowly
thereafter. The early market in September was "soft" in Massa-
chusetts because of carry-over of the 1981 Washington crop. The
carry-over hurt the sales of Paulared and September sales of
Mcintosh.

This and other factors including a large national crop of
apples and oranges, poor fruit color, and storage disorders were

-13-

largely responsible for the unfavorable prices during the 1982-83
marketing season (Table 1). In October, 1981 prices quoted for
Mcintosh Extra Fancy 120 counts in the Special Apple Market Report
averaged $11.00 and by December had risen to #13.25. In contrast,
apples started at $8.75 in October, 1982 and prices were virtually
unchanged fro the remainder of the 1982-83 marketing season.

Summary

For the 5-year period from 1964-68 the national crop averaged
about 132 million bushels. From 1973-77 it averaged 158 million,
a 19% increase. The average production for the 5-year period
1976-80 increased to 178 million, 12% over that of 1973-77. The
production nationally fluctuated from a low of 128 million bushels
in 1967 to a high of 210 million bushels in 1980. To the contrary,
apple production of Massachusetts remained quite stable from 1967
through 1982.

Over supply occurred during the 1969-70, 1970-71, 1975-76,
1980-81 and 1982-83 marketing seasons. Due to heavy plantings,
especially in Washington, it is possible that we may again have
devastating surpluses which will depress prices, increase wastage,
reduce interest in new plantings and cause orchard abandonment.

During the period from 1967 through 1982 many factors affect-
ing the profitability of a marketing season were evident. These
include the size of the national crop, the regional distribution
of the crop, weather prior to and during harvest, the keepability
of stored apples, the demand for processing apples, the export
market and the earliness or lateness of the marketing season.

Table 1. Apple production in the United States and for Massachusetts
and F.O.B. prices at country shipping points in Massachusetts,
1967 through 1982.

Year

Crop size
U.S.

(million bu.)
Mass.

Avg

price for
. Storage

season ($)
CA

CAj

)rice

Start

End

season season

1967

128

2.5

4.58

5.83

5.00

6.75

1968

129

2.1

5.00

6.28

5.75

7.00

1969

159

2.4

4.17

4.46

4.60

4.50

1970

151

2.6

3.75

5.10

4.75

6.00

1971

152

2.7

3.59

3.19

5.10

5.25

1972

139

2.2

5.18

6.31

5.60

7.50

1973

147

1.8

7.23

7.85

7.75

8.15

1974

154

2.2

7.64

8.02

8.00

8.40

1975

179

2.0

6.72

7.70

7.35

8.00

1976

152

2.2

7.89

7.70

8.65

11.00

1977

164

2.1

8.16

9.59

8.75

13.00

1978

182

2.4

9.24

9.98

10.25

11.25

1979

193

2.3

9.28

7.81

9.75

13.40

1980

210

2.3

9.52

9.50

1981

182

2.0

12.27

14.41

13.75

14.75

1982

195

2.4

8.78

8.73

8.25

9.75

-14-

CIDER NOTES
Kirby M. Hayes
Department of Food Science and Nutrition

A question that often arises is how to make good cider.
Although there is no easy answer, or hard and fast rules, two
of the most important factors to consider are maturity and
variety.

Maturity

Firm, ripe apples- - those that are ripe enough to eat out of
hand- -make the best cider and give the highest yield. Immature
or overripe apples lower the quality. Early-maturing varieties
should be allowed to ripen sufficiently to yield a high-quality
juice .

Variety

The best cider is usually made from a blend of different var-
ieties of apples. A blend provides an appealing balance of sweet-
ness, tartness, and tang, as well as aromatic overtones.

A single variety of apple seldom makes a satisfactory cider.
However, "Mcintosh" has been used alone successfully, but only at
the peak of its maturity.

Sometimes the desired fullness and balance can be obtained
from two varieties. A blend of three or more varieties is better.
Using several varieties, permits greater latitude in varying the
proportions to obtain the desired blend, and also allows practical
management of the available supply.

Many commercially important varieties may be separated into
four groups according to their suitability as cider material:
Sweet subacid, mildly acid to slightly tart, aromatic and stringent,
A strict classification is not possible because many varieties have
a number of different flavor characteristics. For example, "Deli-
cious" may be listed in both the sweet subacid and aromatic groups.
Moreover, varieties differ in their characteristics from one area
to another.

Varieties in the sweet subacid group are grown primarily for
eating raw; they usually furnish the highest percentage of the
total stock used for cider.

Varieties in the aromatic group have outstanding fragrance,
aroma and flavor that are carried over into the cider.

-15

Crabapples, in the astringent group, provide tannin - a
constituent difficult to obtain in making a high-grade cider.
The juices of this astringent group also are highly acidic.
Only a small quantity of these apples should be used in the
blend.

Use of the following list as a guide in selecting the right
blend of varieties.

Sweet subacid group: Baldwin, Delicious, Cortland, Spartan,

Empire, Macoun.

Mildly acid to slightly tart group: Winesap, Jonathan,

Northern Spy, R.I. Greening, Roxbury
Ru s s e t .

Aromatic group: Delicious, Golden Delicious, Mcintosh,

Empire.

By fitting the above suggestions to your operation, using
sound clean apples, pressing in a clean mill, and storing and
displaying the finished product under refrigeration, you can
keep your customers coming back for more.

POMOLOGICAL PARAGRAPH

What are genetic dwarfs ? This question is common now that genetic
dwarf varieties of peach, apricot, nectarine and apple are avail-
able to commercial orchardists. Genetic dwarfs are selections of
natural mutants or mutants induced by radiation that produce trees
smaller than typical. Thus, the dwarfing is induced by the scion
variety rather than the rootstock. Trees of Starkspur Compact Mac
and peach and nectarine varieties are very small and could be grown
in a tub on a patio. The internodes on these trees are so short
that the wood is flat and thickened. In contrast, trees of the
genetic dwarf Compact Red Delicious (Cascade strain) has "normal"
appearing wood because of greater internodal spacing and may be
10-12 feet in height when on a seedling rootstock. We are currently
testing the Compact Red Delicious , Starkspur Compact Mac and some
dwarf nectarine varieties at our Horticultural Research Center in
Belchertown.

16-

THE STARCH TEST GUIDE FOR APPLE MATURITY

William J. Bramlage
Department of Plant and Soil Sciences

Once apples begin to ripen, a large portion of the potential
benefit from CA storage is lost, since CA has the capability of
suppressing the beginning of ripening. It is therefore very help-
ful in harvest management to know which apples are and which are
not yet ripening. The most precise measure of the onset of ripen-
ing is through ethylene analyses since ripening is accompanied by
a huge burst of ethylene production. Unfortunately, methods for
measuring ethylene production during commercial harvesting have
been hampered by many technical difficulties and few observers
feel that ethylene measurements are commercially feasible today.

It has long been known that as apples ripen, their starch is
rapidly converted to sugar. Starch concentrations, starch pat-
terns, and starch conversion rates vary among varieties and are
influenced by environmental conditions, yet for some varieties
the changes can be very clear and dramatic. Mcintosh is such a
variety. At the University of Guelph, in Ontario, extensive stu-
dies led to the development of a very simple procedure for
measuring the progress of ripening in Mcintosh by following the
loss of starch from the fruit.

The test is based on the fact that starch, but not sugar,
will react with iodine to form a blue-black color. To perform
the test, a random sample of 10 to 20 fruit are cut open and half
of each apple is immersed briefly in a shallow dish containing an
iodine solution. The apples are allowed to sit a minute or 2 to
allow the color to develop, and the color is then matched to a
chart which tells whether the apples were "immature," "mature,"
or "overmature." For "finer tuning," each of these classes is
subdivided into 3 numerical classes.

This very simple, rapid test allows growers to see for them-
selves the stage of development of their fruit. Periodic sampling
of fruit from different blocks can give them an ongoing view of
where ripening is occurring fastest, and help in determining when
and where to pick. The test also can be a very important guide
in deciding which fruit should be directed into Ck storage. Cer-
tainly, batches of fruit in which a large percentage of the
apples are scoring as "overmature" should not be placed in CA, as
they are too ripe to hold up during and following storage.

17-

All that is needed to perforin the starch tests are (1) a
chart with instructions; (2) some iodine and potassium iodide
crystals; (3) a shallow dish; and (4) a pocketknife. A chart is
available, entitled "Evaluating apple maturity. Using the
starch-iodine test." It can be obtained free from Dr. E.G.
Lougheed, Horticultural Science Department, University of Guelph,
Guelph, Ontario, Canada NIG 2W1. The chart also contains
instructions for testing apples.

The chemicals can be obtained from a pharmacist, who may
have to order them for you. Although they are expensive, small
quantities go a long way. The chart described above includes a
recipe for making up the chemicals, but a simpler recipe has been
suggested by Dr. M.E. Saltveit, Jr., formerly at North Carolina
State University. It is as follows: "First dissolve 1 level
teaspoon of potassium iodide crystals in approximately 1/8 cup
clean water in a 1-quart container. Gently swirl the container
until the crystals dissolve. Next, add 1/4 teaspoon of iodine
and swirl the container until the iodine dissolves. Finally, di-
lute this solution with clean water to make one quart.

This solution is sensitive to light and should be kept in a
dark container, such as a glass jar wrapped in aluminum foil.
Fresh solution should be made every season."

The above chart is designed for use on Mcintosh, and the
brochure contains an accompanying chart for use with Delicious.
North Carolina also has a brochure available with charts for De-
licious, Golden Delicious, and Law Rome. ("Determining the matu-
rity of North Carolina apples. The starch- iodine staining
technique." Publication AG-282). It ws prepared by M.E. Salt-
veit, Jr. and Susan A. Hale, Dept. of Horticultural Science,
North Carolina State University, Raleigh, NC 27650.

We strongly urge growers to try the starch- iodine test for
apple maturity, and to see for themselves the clear changes that
are portrayed by the tests. We believe that the tests will pro-
vide information that will make it easier for growers to make
wise decisions during a very stressful period.

POMO LOGICAL PARAGRAPH

Storage temperature for Mcintosh in CA . The correct temperature
for holding Mcintosh in CA is 36-38-F. Growers operating their
rooms at less than 36 -F are increasing the risk of low temperature
injury, as occurred during the 1982-1983 storage season. Symp-
toms of low temperature injury this past storage season were a
brownish-gray discoloration around the stem-end of the apple
and/or internal browning of the flesh near the core of the apple.

-18-

POSTHARVEST CALCIUM CHLORIDE TREATMENT

William J. Bramlage
Department of Plant and Soil Sciences

Our orchard surveys have shown that approximately one-third
of the commercial samples of Mcintosh apples in Massachusetts are
at such low calcium (Ca) concentrations that they possess a high
risk of developing breakdown after storage. Most other samples
contain Ca concentrations that carry a lower risk of breakdown,
but they could still benefit from some additional Ca.

There are 2 feasible ways of successfully applying Ca to
apples: tree sprays and postharvest drenches. Even when a con-
scientious tree-spray program has been followed, apples can
usually still benefit from postharvest treatment. Thus, posthar-
vest Ca treatments have potentially wide benefit for the fruit
industry.

A postharvest Ca application is viewed as a food-additive
process by the Food and Drug Administration. That agency has
stipulated that "Brining Grade" calcium chloride, containing 94%

^^^^2, is acceptable for postharvest use. The technical flake
CaCl? commonly used for tree sprays is still acceptable for tree
sprays, but it may not be used for postharvest treatments .
There for e~| anyone wishing to use postharvest CaCl2 treatments
must obtain the Briner's Grade material, which is now readily
available from suppliers.

CaCl2 may be combined with scald inhibitors and fungicides
in the postharvest treatment solution. Cornell University has
recommended the following mixture for postharvest treatment of
Mcintosh:

21 lbs of CaCl2 per 100 gal of water

h lb of Benlate* or 16 fluid ounces of Mertect*

1 lb of Captan

1000-2000 ppm DPA
We suggest that h quart of vinegar also be addded to this mixture
in 100 gallons of water. The vinegar neutralizes the CaCl2,
which otherwise makes the solution alkaline. There is evidence
that the alkaline solution may cause the fungicides to break down
rapidly in solution, and the addition of vinegar can protect
against their alkaline degradation.

Trade names

-19-

In use of postharvest CaCl2 drenches, it is important to
understand that little or no Ca enters the fruit during the
drenching process. The purpose of the drench is to leave a resi-
due of CaCl2 on the fruit. Ca is slowly absorbed by the apple
from the residue during storage. Therefore, the drench is never
followed by a rinse, which would remove the residue. Further-
more, for Ca to be absorbed from the residue, the residue must
not dry out. The apples should not be allowed to air-dry before
storage. If the storage is operating at the desired relative
humidity (90-95%), the residue should not dry out. However, if
the storage is operated at less than 90% relative humidity the
residue may dry out and no Ca uptake will occur as a result of
the drench treatment.

We have encountered no difficulty from this residue when
apples are removed from storage. It will be removed if apples
are water-dumped, but even with hand-packed fruit no difficulty
has been reported.

CaCl2 drenches can cause fruit injury, which occurs as tiny
black spots on the surface of the fruit. Generally, these spots
are concentrated in the calyx cup of the apple and are not objec-
tionable, although under some circumstances they may coalesce
into more unsightly blotches or may occur at the lenticels on the
cheeks. Do not exceed the recommended CaCl2 concentration, as
risk of this injury escalates rapidly at higher concentrations.

CaCl2 is also corrosive, so equipment should be thoroughly
cleaned at completion of treatment. However, with appropriate
rinsing corrosion should not be a concern.

The purpose of the postharvest application of CaCl2 is to
reduce the risk of breakdown, rot, and scald during but especial-
ly after storage. The recommended treatment will not make fruit
firmer, but will improve their ability to hold up during market-
ing. Treatments will be of greatest benefit to mature fruit des-
tined for long-term storage. Overripe fruit cannot be expected
to benefit significantly from a CaCl2 treatment.

-20-

ACID RAIN AFFECTS APPLE MAGGOT FLY EGGLAYING

Averill and Ronald J. I
Department of Entomology

1 2

Anne L, Averill and Ronald J. Prokopy

Acid rain occurs when airborne sulfur and nitrogen oxides
originating from combustion of fossil fuels are washed to the
earth during rainfall as sulfuric and nitric acids. In addition
to being a popular topic in magazines and newspapers, this phen-
omenon is a complex political issue: although Massachusetts has
the most acidic precipitation in the country, many scientists be-
lieve that the bulk of our rain's contamination emanates from
Midwestern smoke stacks. Residents of the Northeast have become
progressively concerned and bitter as an increasing number of
scientific studies demonstrate detrimental effects of acid rain,
especially on aquatic ecosystems, soils, and crop and forest
vegetation.

In the course of studies of apple maggot fly egglaying be-
havior, we noted a particularly intriguing effect of acid rain.
Our observations suggested that a host fruit exposed to acid
rain was less acceptable to the flies for egglaying than was an
unexposed fruit. To test this possibility more thoroughly, we
are hanging clean fruits in trees during each of this summer's
rains, with some fruits protected from rainfall by plastic hoods.
These fruits are brought to the lab, and by observing the number
of flies which attempt egglaying, we can evaluate the influence
of rain exposure on fruit acceptibility . Acidity (pH analysis)
of each rain event is determined by Dr. O.T. Zajicek of the Depart-
ment of Chemistry at UMASS. Thus far, most rains have fallen into
1 of 2 categories: those with pH values well below 4 (3.6-3.8)
and those with pH values above 4. These categories largely reflect
the dominant weather pattern at the time of the storm. Usually,
the more acidic contaminated storms (pH 3.6-3.8) move into our
region from the Midwest and the less contaminated storms move in
from elsewhere. The data available to date (Table 1) show that
apple maggot egglaying was not influenced when fruits were washed
by rains with a pH above 4, whereas egglaying was significantly
decreased when fruits were washed by rains of pH 3.6-3.8.

This phenomenon may be explained by the fact that apple mag-
got flies have contact chemical receptors (hairs) which are loca-
ted on the bottom of their feet. Via these receptors, a fly may
receive cues emanating from the fruit to control steps in fruit
acceptance and egglaying. The presence of acids on the fruit
surface may interfere with perception of these cues, or may ac-
tually damage or destroy the chemical receptors.

Whatever the explanation for our observations, it is possibly
to our advantage, and to the disadvantage of the apple maggot fly,
that acid precipitation is most severe in the summer months during
peak fly activity.

2Graduate Student
Extension Entomologist

-21

Table 1. Percent arriving apple maggot flies attempting egglay-
ing into fruits exposed to summer rain storms. Non
rain-exposed fruits were protected from rain under
plastic hoods.

-a ^

Rain with Attempted Rain with Attempted,

pH 4.0-4.2 egglaying^ pH 3.6-3.8 egglaying

Non rain-exposed Non rain-exposed

fruits 50 fruits 65

Rain-exposed Rain-exposed

fruits 55 fruits 46*

, Average of 6 storms
Average of 3 storms
*Signif icantly less than egglaying into non rain-exposed fruits

NEW PUBLICATIONS AVAILABLE

Two new publications are available to the public.

One, entitled "Postharvest disorders of apples and pears,"
was prepared by S.W. Porritt and M. Meheriuk of the Agriculture
Canada Research Station, Summerland, British Columbia, and by
P.D. Lidster of the Agriculture Canada Research Station, Kent-
ville. Nova Scotia. It contains excellent color prints of various
disorders along with very useful information about the disorders.
It is available free, as Publication 1737, from the Communications
Branch, Agriculture Canada, Ottawa, Ontario K1A0C7.

The second publication was prepared by CD. Blanpied and
R.M. Smock of Cornell University and is entitled, "Storage of
fresh market apples." It contains a great deal of information on
current thinking about apple storage management, and is available
as Information Bulletin 191 for a fee from Distribution Center C,
7 Research Park, Cornell University, Ithaca, New York 14850. The
fee is $4.50 per copy. Send a check or money order payable to
Cornell University. Be sure to print your name, complete address,
and ZIP code clearly on your request for the publication.

■22-

FRUIT NOTES INDEX FOR 1983

(This index of major articles has been prepared for those who
keep a file of FRUIT NOTES. The number in parenthesis indicates
the pages on which the item appears.)

WINTER ISSUE - Vol. 48, No. 1

Varieties of Grapes for Massachusetts (2-3)

Varieties of Peaches for Massachusetts (4-5)

Performance of Disease Resistant Apples in Massachusetts (6-9)

Disease Management for Apples in Massachusetts: 1982 Results

and Summary of the Five-Year Program (10-16)
Factors Affecting Nutrient Content of the Foliage and Fruits

of Apple Trees (17-23)
Integrated Management of Apple Pests in Massachusetts, 1982

Results: Insects (24-34)

SPRING ISSUE - Vol. 48, No. 2

Nutritional Problems in 1982 and Suggestions for Fertilization

of Apple Trees in 1983 (1-4)
Effects of Type of Nitrogenous Fertilizer Applied Under

Sturdeespur Delicious Trees on Exchangeable Elements in

the Soil (4-5)
Preliminary Findings from the Multi-State Cooperative Apple

Interstem Planting (5-6)
Future of Tree Fruit IPM in Massachusetts (7-8)
Sampling Soil for Nematodes (9)
Pruning Plum Trees (9-11)

A Visual Monitoring Trap for the Apple Blotch Leafminer (11-14)
Are High Density Strawberries on Ridges for You? (15)
Suggestions for Use of Calcium Sprays in 1983 (16-17)
An Up-date on Calyx-end Rot, and Report of an Apple Leaf Spot

Caused by the Fungus Sclerotinia sclerotior ium (17-19)
Use of Promalin to Increase Branching of Young Trees (20-22)

SUMMER ISSUE - Vol. 48, No. 3

Leaf Analysis Service and Standards for Nutrient Levels (1-4)
Gypsy Moth as a Pest of Highbush Blueberry in Massachusetts (5-8)
Marketing Your Fresh Fruits and Vegetables (8-13)
Spur Blight of Raspberries (14-17)
NRAES-16 Planning Farm Shops (18-19)

Why, When and How to Summer Prune and Results to Expect (20-23)
Extent of Damage by Major Apple Fruit Injuring Insects in
Massachusetts (23-25)

23-

FALL ISSUE - Vol. 48, No. 4

Cycling Fans in Apple Cold Storage Rooms Can Be a Good Way

to Conserve Energy (1-3)
Effects of Mineral Nutrition on Keeping Quality of Massachu

setts Mcintosh: Results of a Four-Year Study (4-8)
The Apple Markets from 1967 through 1982, Locally and

Nationally (9-13)
Cider Notes (14-15)

The Starch Test Guide for Apple Maturity (16-17)
Postharvest Calcium Chloride Treatment (18-19)
Acid Rain Affects Apple Maggot Fly Egglaying (20-21)

Department of Plant and Soil Sciences

French Hall

University of Massachusetts

Amherst, MA 01003

3-20028

Non-Prof it Org.

U.S. POSTAGE

PAID

Permit No. 2
Amherst, MA 01002

FRUIT
NOTES

PREPARED BY
DEPARTMENT OF PLANT AND SOIL SCIENCES

COOPERATIVE EXTENSION SERVICE,
UNIVERSITY OF MASSACHUSETTS, UNITED
STATES DEPARTMENT OF AGRICULTURE AND
COUNTY EXTENSION SERVICES COOPERATING.

EDITORS
W. J. LORD AND W. J. BRAMLAGE

Vol.49: 1

WINTER ISSUE, 1984

Table of Contents:

Subscription to FRUIT NOTES

A Report on the 1983 Apple IPM Program

Variations in Tree Form in an Eight-Year-Oid Spur-Type
Mcintosh Planting

Height Containment on Spartan and Idared Trees

Pomological Paragraph - Increased Interest in Cherry Growing

Response of Interstem Trees to Planting Depth

Using W Clips to Train Fruit Trees

Effect of Mineral Nutrition on Keeping Quality of
CA Mcintosh in Massachusetts

Pomological Paragraph - Differences between M7 and M7a

Issued by the Cooperative Extension Service in furtherance

of the Acts of May 8 and June 30, 1914, United States Department of Agriculture and
County Extension Services cooperating. The Cooperative Extension Service offers equal
opportunity in programs and employment.

FRUIT NOTES SUBSCRIPTION

To subscribe to FRUIT NOTES complete
and mail the following form with your check
for $3.00 (Canadian subscribers, please send
a U.S. postal money order).

William J. Lord
William J. Bramlage
Editors

Name

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Make check payable to: FRUIT NOTES ACTIVITY ACCOUNT

Send subscription form and check to: William J. Lord

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1984

-1-

A Report on the 1983 Apple IPM Program
W.M. Coli-^, R.J. Prokopy-^, and W.J. Manning'

1983 was a year of transition for Apple IPM in Massachusetts, during
which program emphasis shifted from providing scouting and pest management
advisory services for a limited number of growers toward a stronger
educational and information transfer effort for all the state's growers as
well as support of private sector IPM implementation.

Grower interest in and support of IPM continued to be excellent, with
informal surveys indicating that over 2/3 of the state's total apple
acreage is presently under some form of integrated management (e.g. private
sector scout/consultants, grower scouting, careful attention to proper
timing of pesticide application, or selection and use of IPM-compatible
pesticides). In FY 1983, growers contributed $3200 toward the continuation
of the program and apple IPM specialist position — a substantial
committment when one considers that many of these same growers also paid
@$20/acre for private scout/consultant services. Further, a mechanism was
established to lease to private parties 9 hygrothermograph units.

Extension faculty and professional staff conducted or participated in

12 IPM training sessions (usable for pesticide certification credits) (4 in

each of the three major fruit-growing regions of the state.)

Entomology Department
Plant Pathology Department

Acknowledgments: We wish to thank Ms. Kathleen Leahy for scouting and
computer-related assistance.

Special thanks to Glenn Morin and Roberta Spitko for providing a
substantial portion of the harvest injury survey data which is compiled in
Table 2.

-2-

In addition, the Entomology IPM Specialist performed weekly scouting
in six commercial, orchards to collect data and samples on insect/mite and
disease pest status. With the cooperation of Plant Pathology staff (Mr. Dan
Cooley and Dr. W. Manning), Mr. Coli was primarily responsible for
maintaining a frequently updated (2 x weekly), computer-based message
system accessable by terminals in regional fruit specialist offices. These
messages also contained information gathered by other extension staff (Jim
Williams, Tom Green and Ron Prokopy), private sector scouts (Glenn Morin,
Roberta Spitko, Breck Parker, Wayne Rice and Ed Roberts Jr.) and from
weekly access to New York State's excellent computerized information system
(SCAMP). Regional specialists sent this information to growers via weekly
newsletters and 24 hour code-a-phone devices (over 1370 calls were made to
these code-a-phones in 1983, an increase of 20% in utilization over 1982).
Numerous favorable grower comments have been received concerning the
quality of the 1983 pest messages and their value to growers as management
aids.

Table 1 is a graph of weekly totals of calls received on Jim Williams'
and Karen Hauschild's code-a-phones during the 1983 season (data from Dom.
Marini's region are not available since his code-a-phone has no counter.)
Total calls received in these regions were 1222. There are several
interesting points to note in this graph, including:

1. A six-fold increase in use from week 1 to week 2 as the pest control
season began in earnest, particularly with regard to frequent wetting
periods and changes in fungal spore maturity.

2. A substantial drop in calls during bloom, followed by a major peak in
usage during late May - early June. This peak coincides with the

-3-

approaching end of primary scab season, as well as the onset of sprays
against plum curculio and 1st generation leafminer larvae.

3. Another peak during the week of June 21 when 1st generation San Jose
scale (SJS) crawlers first became active.

4. Increased calling from July 12-July 19 following the first reported
apple maggot (AMF) capture in an early developing commercial orchard
(7/11) .

5. A final period of high usage from July 26 to August 9, a time of
decision-making with regard to 2nd generation leafminer (LM) in many
areas.

6. It is somewhat surprising to note the relatively low number of calls
received thereafter, in spite of the impending activity of 2nd
generation San Jose scale crawlers.

Other IPM-related information was published in the form of four "Fruit
Notes" articles, a paper presented at the annual meeting of the Mass. Fruit
Growers Association (co-authored by SJV. Weis, Plant and Soil Science and
Dr. J.M. Clark, Entomology) and a symposium talk presented to the Eastern
Branch ESA Meetings in Hartford Connecticut (co-authored by F. Drummond, T.
Green and R. Prokopy, Entomology Dept). The Entomology Specialist, in
collaboration with Dr. Clark, recently applied for and received a $1200
grant from the M.F.GJ^. to perform laboratory work to further investigate
effects of spray mix pH on pesticide stability and effectiveness.

An additional accomplishment was the receipt of a $6850 grant from
USDA to be used to publish a photographic manual of IPM techniques for use
on apples in New England. This publication, an expansion of the Apple
Insect/Mite Photo manual which many growers have seen at IPM training

-4-

sessions, will contain over 100 4-color photographs with text on major
insect/mite, disease and vertebrate pests of apples as well as a segment on
integrated management of orchard cover crops.

Insect Pest Injury, 1983 - Direct Pests - Table 2 contains results of on
tree harvest injury surveys conducted by extension and private sector IPM
personnel. It is interesting to note that tarnished plant bug (TPB) again
accounted for the majority of fruit injury observed just prior to harvest.
However, with the exception of a few blocks where TPB injury to individual
fruit was severe (similar to "cat-facing" injury on peaches), much of this
"injury" would pass through a grading line with no effect on fruit grade.

While many growers appear to be achieving good San Jose scale (SJS)
control, largely due to improved monitoring and better spray coverage, SJS
ranked second in importance in monitored blocks (range 0-4.3% injury) in
1983. As was the case last year, SJS crawlers continued activity well into
September, when pre-harvest interval considerations made treatment
inpossible.

European apple saw fly (EAS) injury was about at average levels for the
last 5 years (0.40% in IPM blocks, 1978-1982). In 1983, however, much EAS
injury consisted of a "dimple" in the fruit calyx, which would likely not
affect fruit grade.

Green fruitworm (GFW) injury, which will probably result in fruit
culling, was up from 5-year averages, largely due to suspected resistance
to Guthion and Imidan in several blocks. Growers who experienced
substantial injury from GFW in spite of pink and/or petal fall sprays of OP
compounds should consider use of other materials (carbamates, for example)
in the spray program next year. Most other direct pests were of minor
importance in 1983.

-5-

Indirect Pests - Injury from 2 indirect pests, white apple leafhopper
(WAL) , and aphids, was substantial in some blocks. 2nd generation WAL
populations reached outbreak levels immediately prior to Mcintosh harvest
in at least one monitored orchard (active stages exceeding 10 per leaf).
Injury to leaves and excrement on fruit was extensive in this case. A
further problem was the annoyance factor of leafhoppers flying into
picker's faces during harvest. While aphids were controlled by predators
at many sites this year, substantial sooty mold growth on honeydew (as high
as 43% of fruit in one case) can probably be explained by lack of
significant rain showers in many areas.

Pyrethroid insecticides (e.g. Pydrin) provided excellent control of
leafminers in almost all cases. Interestingly, growers who used
pyrethroids averaged only 1.6 percent TPB injury versus the state average
of 2.52%, reinforcing our earlier research plot data which suggested that
pyrethroids may be excellent materials for integrating controls of a key
direct pest (TPB) and a key indirect pest (ABLM/STLM). Growers who applied
carbamate materials against 1st generation miners generally experienced
excellent control results. Where 1st and 2nd generation controls were not
adequate, 3rd generation moth flight was quite large, as expected. A few
growers applied sprays for miners of this generation, even though such
sprays may be more harmful then helpful.

Spider mites (European red mites, two spotted mites) were a problem at
many locations throughout the year, due to hot, dry weather. Frequent
reapplication of miticide was needed in some cases to achieve control.
Even where controls were applied, some locations experienced late mite
outbreaks with renewed hot weather in early September. Levels of our major

-6-

mite predator Amblyseius fallacis ^ were lower than normal this year
possibly owing to low overwintering numbers of this beneficial mite or to
the effects of pyrethroid or carbamate insecticides directed at other
pests.

Plans for 1984 - It appears that funding for apple IPM, as well as for IPM
programs begun in Mass. in 1983 in other commodities, will continue at
present levels in 1984. Based on this premise, we plan to continue with a
similar apple IPM effort, focusing particularly on the IPM training
sessions and maintenance of an extensive, frequently updated, tree fruit
pest message system. We welcome grower suggestions and comments on the
pest messages to ensure that grower needs are met.

As mentioned above, we expect to publish a field manual of IPM
techniques prior to the 1984 growing season. We feel that this publication
will provide growers with a comprehensive field reference to
identification, life histories, damage, monitoring and control measures
for the major New England apple pests.

In addition, Massachusetts will be one of a group of states
participating in a national study on IPM program impact. This study, under
the leadership of Virginia Polytechnic Institute, will examine overall
social and economic benefits of IPM implementation to the state's apple
growers. We will be one of two states in the Northeast (New York is the
other) to focus on apples. It is hoped that this study will provide
information which will be useful in justifying further Federal support for
IPM and in determining areas where program modifications are required to be
more responsive to private sector needs.

-7-

iia-

loa-

Total calls =

14 19 25 29 3 6 10 13 19 24 1 7 10 14 21 26 1 8 12 19 22 26 9 19 31

April May June July August

DATES

Table 1. Code-a-phone use. Northeast and Western regions, 1983.

-8-

Table 2. Percent insect injured fruit in
on-tree surveys of 48 IPM commercial orchard
blocks. 1983^

Insect pest

Tarnished plant bug . 2.52

San Jose Scale 0.49

European apple sawfly 0.41

Fruitworms 0.38

Plum curculio 0.17

Leafrollers 0.07

Apple maggot 0.03

Codling moth 0.00

Total Injury - Direct Pests 4.07

White afple leafhopper 0.22

Sooty mold 1.06

Total Injury - Indirect Pests 1.28

■^Data from 38 blocks receiving private IPM
scouting/consultant services from New
England Fruit Consultants, Mr. Glenn Morin
and Dr. Roberta Spitko. Samples consisted
of 50 fruits per tree on 6-16 trees per
block .

Data from 10 other commercial blocks
collected by Extension IPM staff. Samples
consisted of 100 fruits per tree on 4-10
trees per block.

VARIATIONS IN TREE FORM IN AN EIGHT-YEAR-OLD
SPUR-TYPE McINTOSH PLANTING

C.G. Embree
Agriculture Canada, Kentville, N.S.

Editor ' s Note. The growth habits of Maaspur and Morspur trees are
variable in Massachusetts. Thus, it is of interest to note that
the same difficulty is being encountered with Starkspur Ultra Mac
under Nova Scotia conditions .

Nova Scotia apple
type strains of commer
size control is provid
rootstock such as the
can be used. These tr
adopted 155 (14 x 20)
seedling stock that ha
and orchards in Nova S
other seedlings, hardy
tosh and Cortland.

growers have a keen interest in the spur-
cial apple cultivars. When considerable
ed by the cultivar a more vigorous reliable
locally grown Beautiful Arcade seedlings
ees are not expected to outgrow the widely
planting system. Beautiful Arcade is a
s performed well in experimental trials
cotia, being productive, smaller than many

and a promoter of early yields with Mcln-

Early indications of spur-type variants of Mcintosh from B.C.

coincided with
the development
of a mother or-
chard for the
production of
virus-free,
true-to-name
propagation
material by the
Nova Scotia
Fruit Growers
Association.
Following in-
vestigations of
the various
strains it was
decided that the
Dewar strain was
most appropriate
for this region.
Negotiations with
Mr. Dewar led to
his forwarding a
sample of scion
wood to the Re-
search Station
for testing with
possible inclu-
sion in the mother
orchard .

Fig. 1. Dewar Mcintosh on Alnarp II in P. Van
Oostrum Orchard planted in 1974 exhib-
iting spur- type growth habit. Photo
taken May, 1983.

-10-

Thc scion wood was grafted on Alnarp II roots at about 14"
above the rootzone and grown in a nursery for one year. They were
planted in a growers' demonstration trial in the sprini; of 1974.
Trees were spaced at 15 x 22 at 50 trees per row in two adjacent
rows. Early productivity has been good, as have been fruit color
and size, when compared with other trees in the block. However,
the strain has since been sold to Stark Brothers Nursery and re-
leased as Starkspur Ultra Mac.

Variation in growth habit has become obvious in the Nova

Scotia planting (Figures 1^2)

In 1983 trees with considerable

branching and

Fig. 2. Dewar tree in same block as shown in

Figure 1 but with standard type growth
habit (non-spur) .

side shoots
represented 21%
of this plant-
ing. Forty-six
percent of the
trees had typ-
ical spur-type
growth habit
with virtually
no side branches
on the main
limbs. The re-
maining 33% of
the trees had
some degree of
spur-type char-
acter but some
side branching
was also present
Detailed records
of the number of
spurs per meter
of growth and th
amount of extens
growth will be
recorded in 1984
prior to pruning

ion

Reports of variation in spur-type tree from have been observed
in other strains and cultivars in Nova Scotia orchards but no ratings
have been done at this time.

It is of interest to note that some trees in this block had
little or no bloom in 1983. This is also true of Idared on MMlll
and Spy on M26. It should be noted that the soil in this planting
is quite coarse and excessively drained. This coupled with the
very dry harvest season and heavy crop in 1982. appears to have
accentuated an inherent biennial bearing tendency. Concerns of
this tendency in the spur types are described in 1973 publication
titled, "Spur-Type Apple Trees" and is available from the author.

-11-

HEIGHT CONTAINMENT ON SPARTAN AND IDARED TREES

William J. Lord and Anthony W. Rossi
Department of Plant and Soil Sciences

In the January/February, 1980 issue of FRUIT NOTES we dis-
cussed our progress with height containment of Spartan and
Idared trees on M7a rootstocks. The objective of this demon-
stration was to answer 2 questions: (1) What is a suitable
pruning method for containing tree height?, and (2) What is
the influence of height reduction on yield? Below we have:
(1) summarized previously reported findings through harvest in
1979, (2) included our data and observations for the last 3
years, and (3) described containment pruning.

Summary of Previous Findings Through Harvest, 1979

Limb rotation in the top third of the crown of Spartan and
Idared trees on M7a rootstock was a suitable procedure for con-
taining tree height. The pruning demonstration was initiated
in February, 1976, and after dormant pruning in February, 1979,
the average height of the control trees was 2.5 feet greater
than that of the height- restricted trees. In spite of the
height difference, yields were not consistently reduced from
1976 through 1979 on the height-reduced trees (Table 1) .

Table 1. Influence on yield from height reduction of Spartan
and Idared trees .

Year

Spartan^
Height

reduced

control

Idared'

Height
reduced

control

1976
1977
1978
1979
1980
1981
1982

Cumulative
yield

6.0a

4.0b

10.4b

9.6h

6.5a

14.0a

13.1b

64b

Bushels/tree

8.0a

5. 3a
12.5a
12.2a

6. 3a
16.3a
14.4a

76a

6.2a

7.5a

4.1a

4.8a

10.2a

12.4a

8.9b

11.4a

8.2a

9.5a

9.3b

11.7a

14.2b

15.2a

61b

73a

Trees planted in 1964; trial started in February, 1976.

Tree height 3/79: Control, 11.4 ft.; height-reduced trees,

8.9 ft. Height 3/82: Control, 12.5 ft.,; height-reduced trees,

8.5 ft.

Tree height 3/79: Control, 10.6 ft.,; height - reduced trees,
8.3 ft. Height 3/82: Control 11.8 ft.; height- reduced trees,
8.1 ft.

Means in any row for each variety followed by different letters
are significantly difference at odds of 19 to 1.

12-

Results Through Harvest of 1982 and Conclusions

Containment pruning to restrict tree height continued to
be successful. The height difference (measured at top of
central leaderj between the control Spartan and Idared trees
and the height-restricted trees of these varieties now averages
4.0 and 3.7 feet, respectively. Although the influence of
height restriction on yield still is not consistent (Table 1) ,
the cumulative yields for the 7 years have been 12 bushels
less per tree on the height-restricted trees.

The harvest crew has expressed its preference for the
height-restricted trees but the yield reduction may be unaccept-
able to most growers. Theoretically, yields per acre of the
height-restricted and control trees would be similar if the
shorter trees were spaced 20% closer. For example, the trees
in this trial are spaced 20 feet x 30 feet (72 trees/acre) . To
increase tree numbers by 20% (86 trees/acre) one would plant
the trees at 18 x 28 foot spacing.

Containment pruning will work on many varieties but certain
varieties are much more vegetative than others. We have en-
countered no difficulty in maintaining the Idared and Spartan
trees on M7 at 8.3 feet and 9 feet, respectively. However, tree
height of 9 feet is too low for the innate vigor of non-spur
Delicious on M7 at our Horticultural Research Center. In con-
trast, spur-type trees of Delicious on M7a could be easily
maintained at 9 feet (height of central leaders) .

Procedures Suggested to Contain Tree Size

1. Branches that crowd those of adjacent trees will have to be
removed or cut back to a weaker side branch. (Cuts made
only to maintain the desired outer profile of the tree com-
pounds rather than alleviates tree containment problems.
Such cuts stimulate vigorous growth and by the end of the
next growing season, the limb may extend as far as the
original branch did before shortening, and may cause more
shading within the tree than did the original uncut branch.)

2. Maintain conical tree shape by removing large limbs in the
top third of the tree or cutting them back to a very much
weaker side branch.

3. Initiate a limb rotation program in the top third of the
tree by retaining weak branches or spreading desirable water
sprouts, which in turn may have to be removed when they be-
come too large.

4. Reduce the height of excessively tall trees by cutting them
back to a strong outward growing lateral branch originating
at a lower level on the leader.

-13-

5. Frequently a strong scaffold branch with a narrow crotch
angle develops in the upper third of the tree. If this
branch is not removed or its growth is not restricted,
the tree will become a multiple leader tree. Trees of
this type are much more difficult to prune when practicing
containment pruning or lowering tree height.

6. Delicious trees are subject to weak crotches, and branches
are prone to develop in whorls and to droop. The ends of
drooping branches should be removed back to a lateral grow-
ing in a somewhat upright position. This will shorten

and stiffen the branches. The tip of the lateral on a
pruned drooping branch should be higher from the ground
than any other portion of the branch. This should reduce
the problem, of suckering.

**********

POMOLOGICAL PARAGRAPH

William J. Lord
Department of Plant and Soil Sciences

Increased Interest in Cherry Growing . Interest in cherry grow-
ing has increased in Massacnusetts because of labeling permitting
use of Mesurol* for repelling birds. While sour cherries are
relatively winter hardy, sweet cherries may be severely injured,
if not killed, by low temperatures. However, sweet cherries
can be grown successfully with limited amounts of nitrogenous
fertilizer. To eliminate or reduce injury to sweet cherry
trees caused by low temperatures, the soil under the trees should
not be cultivated.

Sour cherry trees are smaller than sweet cherry trees and are
better suited for U-pick operations. At this time we cannot
recommend the use of dwarf rootstocks for either sweet or sour
cherry trees.

Several sweet cherry varieties you may want to consider are
Emperor Francis, Schmidt, Hedelfingen and Windsor. Montmorency
is the most popular sour cherry variety; other varieties are
EArly Richmond, English Morello, North Star, and Meteor. North
Star and Meteor produce much smaller trees than the other varieties

Trade name

RESPONSE OF INTERSTEM TREES TO PLANTING DEPTH

1 2

William J. Lord and Joseph Costante

The responses of Empire, Rogers M
Oregon Spur Delicious trees on M9/MM
planting depth were investigated in
at the Green Mountain Orchards, Putn
Joseph Costante, Extension Fruit Spe
author. The planting depth treatmen
line approximately 2 inches below th
union; (B) the soil line at the mid-
and (C) the soil line approximately
piece/variety union (see diagram bel
the trees was 7 inches. The i'nforma
findings at the completion of the st

cintosh, Macspur and
106 or M9/MM111 to
an experiment initiated
ey, Vermont in 1976 by
cialist and the senior
ts were: (A) the soil
e stempiece/rootstock
section of the M9 stempiece;
2 inches below the stem-
ow) . The stempiece on
tion below summarizes the
udy in November, 1982.

variety

SOIL LINE

Planting depth A

Planting depth B

Planting depth C

-15-

Cultural Problems .

Tree training difficulties were experienced particularly
with Empire because the central leader lost its dominance.
Leader leaning, which was corrected by staking, appears assoc-
iated with the growth characteristics of Empire on interstem
trees on M26 rootstock rather than due to cropping. None of
the trees needed staking because of poor anchorage.

The burrknots on the M9 stempieces on trees particularly
at the (A) and (B) (the soil line at the mid-section of the stem-
piece) planting heights were the entry sites of apple bark borer
larvae in 1981. These were eradicated manually by probing for
the larvae with a knife as well as scraping with a wire brush.
Observations here, and at other locations have led us to conclude
that the problem is associated with the use of mouse guards made
of plastic which impede adequate coverage of pesticide sprays on
the tree trunks.

Crovvfth and Yield

Burying or partially burying the stempiece tended to decrease
the number of root suckers and increase the trunk cross- sectional
area (TCA) and yield efficiency, but did not affect tree height
and spread. Trees with the stempiece exposed had smaller trunks
than those with the stempiece buried, but trees with the stempiece
partially exposed did not differ in TCA from those at the other
planting depths. Trees with the stempiece exposed produced the
most root suckers regardless of the cultivar/inter stem/rootstock
combination. These findings support the claim of Carlson in Michi-
gan that deeper planting reduces the tendency of interstem trees
to produce root suckers.

Since root suckering was most severe when the stempiece was
exposed, the question was posed whether the amount of suckering
affected tree growth. There was a negative correlation between
number of suckers and trunk circumference (r = -.15, p = .02).
Because tree size varied across rootstock and cultivars, each
rootstock and cultivar were evaluated separately. The number of
suckers correlated negatively with trunk circumference for M9/MM106
(r = -.23, p = .01) and the Macspur (r = -.33, p = .01) and Mcin-
tosh (r = -.48. p = .001). Ferree in Ohio reported a positive
correlation between number of root suckers and trunk circumference
on interstem trees with the lower union of the stempiece 5 cm above
the soil line.

-16-

The trees were slow in coming into production partly due to
poor tree quality at planting and poor growth in the orchard. The
first crop was harvested from the Empire, Macspur, and Mcintosh
trees in 1980 and from Oregon Red Spur Delicious in 1981. Thus,
the yield data was still inadequate at the completion of the study
in 1982 for a good evaluation of the influences of planting depth
on yield and this problem was confounded by the fact that the
orchardist inadvertently harvested the Macspur and Mcintosh in
1982, Preliminary data for the Empire and Delicious show that
trees with the stempiece exposed have produced less per TCA than
those with the stempiece buried. Yield efficiency of trees with
the stempiece partially exposed was not different from the others.
Both the growth and limited yield data support the suggestion that
interstem trees will be weakened and bear less if the stempiece is
above the soil line.

The rootstock and/or cultivar had more effect than planting
depth on several factors. Tree spread was greater for trees on
M9/MM106 than on M9/MM111. Delicious trees were smaller and had
less bloom than the other cultivars. Macspur had less branch spread
than Mcintosh or Empire.

Roots from burrknots were present on all but 3 trees with the
stempiece buried. Conditions were considered very favorable for
rooting from the burrknots because the soil had been heavily mulched
with hay since 1980 and rain was ample for optimum grov;th. Never-
theless, 26% of the stempieces had only short, fibrous roots less
than 18 cm in length. Since the trees were not dug up, the original
roots could not be observed but it does seem that this rooting may
be too limited to entirely replace the original roots as was
observed by Rogers and Parry in England. Rootstock and cultivar had
no influence on the amount of rooting.

After 7 growing seasons, interstem trees of Oregon Spur Red
Delicious are smaller and less productive than similar trees of
Empire, Macspur and Rogers Mcintosh. It appears that because of
the upright branching nature and small leaf surface, the spur-type
Delicious strain is slow to develop.

Summary

Production of root suckers by interstem trees can be reduced
by deeper planting. Our limited observations lead us to conclude
that interstem trees will require more care than those on vigorous
size-controlling rootstocks and that the stempiece is a site for
possible difficulty with weather, rodents, insects and disease.
Further testing is needed before we can recommend planting of inter-
stem trees other than for trial.

-17-

USING W CLIPS TO TRAIN

FRUIT
1

TREES

George M. Greene'
Associate Professor of Pomology
Pennsylvania State University
Fruit Research Laboratory, Biglerville, PA

Most frui
with the use o
pins to spread
shoots of upri
vars. The use
help good crot
and will help
becoming trapp
leader and the

t growers are familiar
f spring-type clothes

young 2-4 inch long
ght growing apple culti

of this technique will
ch angles to develop
prevent dead bark from
ed between the central

lateral scaffold limbs

Unfortunately many upright grow-
ing cultivars need additional branch
spreading in years 3 through perhaps
6. Most fruit growers are familiar
with the use of wooden spreaders
(with nails in the ends) to spread
laterals away from the central leader
into a more horizontal position. This
spreading tends to reduce the vigor
and increase the fruitfulness of the
spread branch. In addition, if
lateral branching can be encouraged
on the spread scaffold limbs, trees
will tend to be more productive since
more sunlight can be intercepted by
the enlarged tree canopy. The author
saw VI clips being used in England in
1979 to spread branches but no source
of the clips in the U.S. was known.
However, hop growers in Washington use
this style of clip to help construct
the string trellises to support hop

Pennsylvania Extension Hort Series II:
permission of the author.

140, 1983. Reprinted by

•18-

plants. For fruit trees, the clips
can be used to hold plastic ba'ler
twine in the ground to spread
scaffold limbs and to hold erect,
young trees that have leaned. A
loop is placed in the end of the
twine and the loop is placed onto
the W clip that has been placed on
the end of the applicator. In the
spring when the soil is moist, the
^^ clip can fairly easily be forced
6-10 inches into the ground. The
plastic baler twine can then be used
to straighten up a tree trunk or to
spread a branch. The advantage the
W clips over wooden spreaders is
that the point of application of the
spreading force can be placed any-
where along a limb. By moving the
point of spreading force further out
on the limb, some of the spreading
action can be placed onto the limb
itself and less placed on the crotch.
The flexibility in being able to
move the point of attachment seems
to be a major advantage over wooden
spreaders. In addition, for those growers interested in spreading
peach and other Prunus species, the W clips and baler twine have an
advantage in that no nail holes are made in the bark where cytospora
canker could enter the tree.

On the negative side, the twine coming out of the ground up to
the branches must not be hit with equipment. Using an offset nozzle
at the end of the weed boom should allow herbicides to be applied
without hitting the trees.

Supplies :
Source :

W clips - 2000
Applicator - 4

per carton, 22 lbs
lbs.

Hop Growers Supply Co., Inc.

PO Box 325

Toppenish, Washington 98948

Attn: Jim Owens

Phone: (509)865-3731

Cost

1 carton (2,000 w clips)
1 clip applicator
U. P. S . on cl ips
U.P.S. on applicator
Handling

$18.40

10.90

10.06

3.51

10.00

$52.87

Editor's Note:

Cost of supplies based on quotes received July, 1983
At press time we were informed that Orchard Equipment and Supply
Company, Conway, MA 01341 sell W clips and twine.

-19-

EFFECTS OF MINERAL NUTRITION ON KEEPING QUALITY
OF CA McINTOSH IN MASSACHUSETTS

W.J. Bramlage, M. Drake and S.A. Weiss
Department of Plant and Soil Sciences

In the previous issue of FRUIT NOTES (Fall Issue, 1983)
we reported results from a four-year study showing relation-
ships of mineral nutrition to keeping quality of Mcintosh apples
kept in air storage. We now have the results from this study
showing how mineral nutrition is affecting keeping quality after
CA storage.

As described previously, 172 orchard blocks were sampled
over a 4-year period. One bushel of apples from each block was
stored in CA at 31 Oj, S% CO2, and 36°F for approximately 8 mon-
ths, then kept 70-80 degrees F. After 1 day firmness was measured
and after 1 week the apples were examined for the occurrence of
breakdown, rot, scald, and bitter pit. However, scald and bitter
pit were too infrequent on these samples for any relationships to
mineral concentrations in the fruit to be established.

Maintaining fruit firmness is vitally important to quality of
Mcintosh after storage. In these tests firmness was measured at
harvest and after storage. As we reported previously for air
storage, mineral concentrations had no relationship to firmness
after CA; all correlation coefficents were non- significant . Fruit
maturity at harvest and postharvest conditions, not mineral concen-
trations, are what regulated fruit firmness in these tests.

Although the fruit were stored 3 months longer in CA than in
air storage, the CA samples generally developed less breakdown and
rot than did- the air-stored samples because CA greatly slows down
changes in apples. Therefore, with smaller amounts of these problems,
relationships of minerals to them tended to be lower than were the
relationships to the same problems after air storage. This is
illustrated in Table 1. Correlation coefficients express these
relationships in such a way that the larger the number (whether it
is positive or negative), the closer is the relationship. It can
therefore be seen that in nearly every case, the relationship be-
tween a mineral and a problem is somewhat less for CA-stored than
for air-stored samples.

Table 1 shows that mineral concentrations affected the occurr-
ence of rot after storage. In this relationship, P concentration
was more important than that of Ca. However, rot can generally be
controlled by use of fungicides in postharvest treatments, which
were not used in these tests.

-20-

For breakdown after CA-storage, Ca was twice as important as
any other element. This relationship is shown graphically in

any otner element. inis reiatiunsnip ib snown grapnicaiiy in
Figure 1, where the percent ofthe fruit that developed breakdown
after CA storage is plotted in relationship to the Ca concentration
in the sample at harvest. This graph is virtually identical to
the one presented in our previous article on Air-stored fruit. As
pointed out then, samples very low in Ca (e.g., less than 130 ppm)
almost always developed breakdown in more than 101 of the fruit,
while samples high in Ca (e.g., more than 175 ppm) almost never
developed breakdown in 10% or more of the fruit. Between these
extremes, the lower the Ca the more likely the fruit were to develo
excessive amounts of breakdown, although other factors probably
determined whether or not these intermediate-Ca apples actually
developed breakdown. These results show once again the importance
of Ca in preventing breakdown of Mcintosh apples during and after
long-term storage.

Table 1. Correlation coefficients relating mineral concentrations
in apples at harvest to occurrences of internal breakdown and
rot after storage in air at 320F for 5 months, or after CA
storage at 360F for 8 months.

Element

Breakdown after

Rot

after

ir storage

CA storage

Air storage

■ CA storage

Calcium

-.40***

-.37***

-.19**

-.14*

Phosphorus

-.33***

-.16*

-.31***

_ 27***

Magnesium

-.22**

-.14*

-.22**

-.14*

Potassium

+ .12

-.13*

.00

Nitrogen

-.35***

-.18**

+ .06

-.17*

Asterisks indicate the statistical odds that a real relationship
exists :

Odds of 19:1; **Odds of 99:1; ***Odds of 999:1

-21-

100

o
cr

60 -

40 -

r --.37*"

• \» ••#i^» • • • • •*. •• — -:~-

, •• • * *^ #••• J • «» «

100

130 160 190

CALCIUM, OUTER CORTEX TISSUE(ppm)

2 50

Figure 1. Relationship between occurrence of internal breakdown in
Mcintosh apples after CA storage and the concentration of
calcium in the samples at harvest. Points represent 172
samples taken over a 4-year period.

**********
POMOLOGICAL PARAGRAPH

V/illiam J. Lord
Department of Plant and Soil Sciences

Differences between M7 and M7a . Occasionally we are asked what is
the differences between Mailing (M) 7 rootstock and M7a rootstock.
The rootstocks are similar except that M7a has been selected for its
freedom from the so-called "latent viruses". These are viruses that
are commonly present in apple varieties and include stem pitting,
chlorotic leaf spot, platycarpa scaly bark and apple stem grooving.

FRUIT
NOTES

PREPARED BY
DEPARTMENT OF PLANT AND SOIL SCIENCES

COOPERATIVE EXTENSION SERVICE,
UNIVERSITY OF MASSACHUSETTS, UNITED
STATES DEPARTMENT OF AGRICULTURE AND
COUNTY EXTENSION SERVICES COOPERATING.

EDITORS
W. J. LORD AND W. J. BRAMLAGE

Volume 49 No. 2
SPRING ISSUE, 1984

Table of Contents

Heading Cuts on Apple Trees Reduce Yields

Pomoiogical Paragraph — Soil and Plant Tissue Testing

Recommendations for Fertilizing Apple Trees and
Increasing Calcium Content of Fruit

Care of Trees on Arrival from the Nursery

Practicality and Longevity of Hardpan Modification

The Apple Maggot in Massachusetts, Michigan and
West Coast States

Gala — An Apple Variety Worthy of Trial

The Use of Promalin to Improve the Shape of
Delicious Apples

Freedom: A New Disease-Resistant Apple

Performance of Disease-Resistant Apples

Gray Mold on Strawberries

Issued by the Cooperative Extension Service in furtherance

^■^S> ^^^^^^^^^^^^H

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^P^M M

HEADING CUTS ON APPLE TREES REDUCE YIELDS

W.J. Lord, R.A. Damon, Jr., J. Sincuk, and K.E. Slossepl

University of Massachusetts

In the past there was a general agreement in most fruit growing areas in the East on
the basic principles and procedures recommended for training young apple trees. A
central leader or modified central leader tree was usually favored, such a tree had the
scaffold branches spaced 8 or more inches apart and spirally around the leader. To
develop this tree thinning cuts were most often used; heading cuts were suggested only
when necessary to balance the length of the scaffold limbs. We define pruning cuts as
follows: Heading, reducing the length of 1-year-old wood by 25%; Stubbing, reducing
the length of the branches with cuts made into 2-year-old or older wood; Thinning, remov-
ing an entire shoot or branch at its junction with another shoot, branch or leader. Since
the early 1970's pruning by heading cuts increased drastically in apple orchards throughout
northeastern United States. On young, non-bearing trees, heading cuts are being used to
stiffen branches, increase the length of the extension shoot of structural limbs, and
particularly to increase secondary branching from structural limbs. In bearing orchards
branches are headed to control size and shape of trees particularly when too closely
spaced. The cuts are made with hand held tools and machines.

During the last 7 years we have made extensive studies of growth and fruiting responses
of Redspur Delicious trees to heading cuts. Our findings are summarized below.

Methods and Materials

The trees used in this experiment were planted in 1976, during the first growing season
pruning was limited to the removal of branches arising within 18 inches of the ground. In
March, 1977 the following pruning treatments were established and continued through 1982:
(1) control[(conventional) Fig. la]; (2) thinning limbs to develop tiers and dormant heading
cuts on I-year-old wood [(Tiers and Heading) Fig. IB]; and (3) minimum pruning (Slender

Fig. 1A.

Fig. IB.

Two year old tree being pruned by standard prun-
ing procedures. The lowest limb should be 18 to
20 inches from the ground, all others spaced 4 to
8 inches apart vertically on the trunk and each
one about 90° around the trunk from the one
below it.

Two year old tree being pruned as suggested by
the USDA. It has 2 layers of limbs. The leader
will be headed annually [heavy marks ( — ) indi-
cate heading cuts] . The one year old wood on the
branches is headed annually until branches on
which this wood is borne start to fruit.

^Extension Fruit Specialist, Statistician, and Technical Assistants, respectively.

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Spindle). All trees were trained to the central leader, free-standing pyramidal form.
Limbs that required positioning were spread to a 45° to 60° angle to promote strong
crotches and early bearing.

Procedures followed in training trees to the Conventional system were as follows:
(1) removing branches with narrow crotch angles; (2) removing undesirable branches to
eliminate whorls and thus permitting only 1 branch to develop at a given level; (3) main-
taining the dominance of the leader by suppressing or removing competing leaders;
and (4) restricting too rapid development of certain structural (scoffold) limbs by stubbing-
back to an outward horizontal shoot or branch. The objective was to develop a central
leader tree with structural limbs symmetrically arranged around the vertical axis of the
leader and spaced 8-12 inches verticallywith none directly above one another. Most cuts
were thinning and stubbing cuts.

Trees trained by the Tiers and Heading system received heading cuts on 1-year-old
wood each dormant pruning season, starting in March, 1977, to shorten by 25% (a) the
extension shoot of the central leader; (b) the extension shoot of each structural branch;
and (c) each lateral shoot longer than 20 cm on structural branches (Fig. 2) . These cuts

MOW TO GET IMt HIGH DENSITY T«EE OFF TO A GOOD STAIT.
HEAVY MASKS SHOW WHEII PRUNING CUTS SHOULD «E MADE

1-y«ar-otd itttion R«mov« oil
compiling ihooti Hcod bock l«r-
minal ihoot

3-y»or-old lethoo Sel«(t and
h«od lof«rol bron<h«i R«n<ov«
unnacciiary lat«raU

3-y«of-old i«cf<on Spfcod broncH-
»t, remov* foiksd termtnaU 'o o
lingl* ihoot and htod thol ihoof.
H*ad fidt ihoott

4-yaor old f«ction Spraod branch-
• t. f«move loried t«m\inoli to o
lingle ih»et and hood thol thool
Hood fid* ihoolt

S-yoor-old lOclton ond oldor If
ffoe hoi fillod ollotlod tpoco,
hood botk whofo noioiionr into
I yoor old wood to on yntioodod
lido ihoot Avoid hooding cult
into l-y«Of-old ihooti ont.l tho
Iroo It fruiting woll

Fig. 2. A diagram of the "constructive training" program suggested by Dr. D.R. Heinicke in \JSDA Agriculture Handbook
No. 458 entitled "High Density Apple Orchards— Planning, Training and Pruning." (Reproduced with permission of
the author.) >

were made to encourage development of lateral shoots which eventually became structural
branches originating from the central leader or secondary branches as suggested by D.R.
Heinicke and illustrated in Fig. 2. The lateral shoots on the central leader were thinned to
create tiers of structural limbs spaced 20 to 24 inches apart. The headed wood generally
produced a cluster of vigorous shoots directly behind the cut during the following growing
season. Each summer when these shoots were 4 to 6 inches long, one was selected for the
permanent extension shoot and 2 competitors were removed by hand to simulate the growth
on a non-headed branch and to prevent excessive proliferation of the extension shoots.

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On Slender Spindle trees the strong vertical leader was removed during dormant
pruning and a weaker, upright-growing competitor was retained for the new extension
shoot to weaken growth in the top of the tree. All lateral branches developing from

Fig. 3. Structural branch from 'Redspur Delicious' trees on which no heading cuts
have been made. The secondary branching is shorter than on the branch
shown in Fig. 4 but it has more fruit spurs and has been more productive.

-4-

the central leader were utilized unless they iiad narrow crotcli angles or competed
with the central leader.

Fig. 4. Structural branch from 'Redspur Delicious' tree on which heading cuts were
made annually for 4-consecutive years. The white lines mark where heading
cuts were made. The bearing surface on this limb is slightly greater than on
the "typical" non-headed branch shown in Fig.3 but the procedure eliminated
many potential fruiting spurs.

-5-

Results and Discussion

Heading all of the 1-year-old shoots during dormant pruning followed with removal
of 2 shoots directly below each heading cut during the growing season to leave 1
terminal extension shoot, increased lateral growth some years but not others (Fig. 3
and 4). However, yields were reduced on the Tiers and Headed trees in comparison
to the Conventional and Slender Spindle Trees (Table 1).

Table 1. Effects of pruning systems on tree size, and yield of redspur Delicious trees
on M26.

Variable

Year

Conven-
tional

Increase in trunk

circum. (cm)

1977

3.73aZ

1978

3.62a

1979

2.74a

1980

3.04a

1981

3.32a

1982

2.50a

Yields (bushels)

1979

0.2ab

1980

0.8a

1981

l.Oab

1982

3.4a

Cumulative Yield

(bushels)

1982

5.4a

No. scaffold

limbs/tree

1982

13a

Tree height (ft)

1982

10.8a

Tree spread (ft)

1982

9.6a

Pruning Treatment

Tiers & Slender

heading spindle

3.06b

3.41ab

3.44a

3.72a

3.04a

2.68a

3.13a

3.20a

3.10a

3.54a

3.09a

2.48a

0.1b

0.3a

0.4b

0.8a

0.8b

1.2a

2.6b

3.5a

3.9a

5.8a

13a

L7a

10.7a

8.2b

10.0a

^Mean separation in rows by Duncan's range test, 5% level.

The decreased productivity of the Tiers and Headed trees was clearly a result of
the heading-back cuts since the number of structural limbs per tree and tree size
at the completion of the study, with the exception for branch spread, were smiliar
among treatments (Table 1). The spread of the Tiers and Headed trees was less than
that of Conventional and Slender Spindle trees because the branches were more up-
right due to lighter cropping. Heading cuts reduced the length of 1-year-old wood,
forced some lateral buds to produce vigorous shoots rather than flower buds; and removed
the most productive section of the wood because the apical sections have more blossom
clusters and fruit than the more basal sections of wood.

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Our findings agree with a similar study conducted by Lord and Sincuk (2) with Spartan
apple trees and with experiments of Elfving and Forshey in New York state (1). The latter
workers used heading cuts of various severity on vigorous 1-year-old wood of a non-spur
Delicious. Increased severity (removal of a greater fraction of 1-year-old wood) produced
increased shoot growth from 1 and 2-year old wood. Fruitfulness decreased as severity increased.

It is of interest to note in Table 1 that yields on the Conventional and Slender Spindle
trees were comparable. However, the annual practice of removing the strong extension
shoots of the central leader and using a weaker upright growing competitor as the new
extension shoot on Slender Spinle trees to produce a zig-zag growth pattern was discontinued
after the 1979 dormant pruning season due to difficulty in maintaining leader dominance.
Trees on M26 seem to react more to unfavorable growing conditions tha those on more vigorous-
size controlling rootstocks and the central leaders often require support but we also encounter-
ed problems with apical dominance with Spartan trees on IV17a rootstock trained as Slender
Spindles (2). These results and observations in a trial with Gardiner Delicious on MM106,
IVIYa and M26 suggest that pruning the leaders to develop a zig-zag growth pattern and to
reduce growth should be delayed on free standing trees until the leader nearly attains
the height desired for the tree.

Summary

In todays economic climate of high interest rates growers must obtain a return on
capital investment as soon as possible. The key to early fruiting is the planting of a well-
feathered (branched) tree and the rapid development of a productive bearing surface.
The grower has little control over the quality of the nursery stock, except to reject inferior
trees; but has no one to blame but him/herself if early yields are reduced by improper
pruning, especially an excessive number of heading cuts. Emphasis should be on training
rather than pruning young trees since fruiting is the key to control of vegetative growth.

Certainly, some pruning is necessary but the majority of cuts should be thinning rather
than heading cuts on trees of all ages. Thinning cuts usually improve light penetration
into the tree, thus increasing carbohydrates that encourage flower bud initiation. Heading
cuts encourage vegetative growth which may increase shading in the interior of the tree and
reduces fruitfulness.

Fruiting decreases from the exterior to the interior of the tree and much of the wood
4 years or older may have few, if any, flowering spurs. Thus, the 2- and 3-year-old wood
is of great importance to the fruitfulness of apple trees and should be subjected to only
modest pruning using thinning rather than heading cuts.

Literature cited

1. Elfving, D.C. and C.G. Forshey. 1972. Growth and fruiting responses of vigorous

apple branches to pruning and branch orientation treatments. J. Amer. Soc.
Hort. Sci. 101:290-293.

2. Lord, W.J. and J. Sincuk. 1980. Progress report: Pruning effects on growth and

fruiting of Spartan apple trees. Massachusetts Agr. Ext. Serv. Fruit Notes
45(5):l-8.

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POMOLOGICAL PARAGRAPH

William J. Lord
Department of Plant and Soil Sciences

Soil and Plant Tissue Testing. Occasionally we receive inquiries from persons
from other states about having leaf samples and/or soil samples analyzed at
the Suburban Experiment Station in Waltham, Massachusetts.

The service is avilable to all persons regardless of residence. To receive
containers for soil and/or leaves, individuals desiring this service should complete
and mail the following form with a check made payable to Soil Testing labor-
atory. Send form and check to Suburban Experiment Station, 240 Beaver Street,
Waltham, MA 02254.

Soil is analyzed for pH and elements. Leaves are analyzed for 16 major and
minor elements.

Order form

Please send me the following kits:

Soil @ $5.00 each.

Leaf sample @ $10.00 each.

Enclosed please find $ .

Name:_

Address

_^ ^^^ zip

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RECOMMENDATIONS FOR FERTILIZING APPLE TREES
AND INCREASING CALCIUM CONTENT OF FRUIT

William J. Lord and W.J. Bramlage
Department of Plant and Soil Sciences

NITROGEN (N)

Many apple orchards are established in sod although we suggest eliminating the
sod by plowing and disking or if the soil is extremely stony, by herbicides. If the
site has been properly prepared and pH and nutritional problems have been corrected,
no fertilizer may be needed the year of planting. However, trees planted on hay
fields or pastures without extensive land preparation should receive N. Those planted
on land previously in forest generally should receive a fertilizer containing both major
and minor elements.

Non-bearing trees. Lime but not fertilizer or manures can be put in the planting
hole with the roots. Fertilizer, a complete fertilizer, or one containing N, potassium
(K„0) and minor elements, should be applied after a rain has firmed the soil around
the roots of the newly planted tree. Fertilize at the rate If 1/3 - 1/2 pound of
ammonium nitrate (33% N) or its equivalent by spreading lightly in a wide circle around
the tree (8 to 12 inches from the tree trunk).
12 inches from the tree trunk).

Table 1. Fertilizers, their nitrogen (N) content, and pounds that must be applied to
equal a certain amount of actual N.

Fertilizer % N Approximate pounds that must be applied to be

equivalent to the following pounds of actual N.

0.3 lb .6 lb 1.0 lb

2.2

3.0

6.3

20.0

12.5

10.0

It is extremely important to obtain good growth on the trees in their non-bearing
years. However, water rather than N may be the limiting factor some years on some
sites.

N is usually applied at high rates to stimulate growth of trees while non-bearing.
For example, at our Horticultural Research Center in Belchertown, MA, young,
non-bearing trees may receive 0.3 - 0.6 lb of actual N/tree whereas bearing trees
receive 0.0 - 0.3 lb of actual N/tree.

After the year of planting, fertilizer, either nitrogen (N) alone, a complete
fertilizer, or a fertilizer containing N and potassium (K„0) and minor elements, should
be applied 3 to 4 weeks prior to bloom and at a rate of 1/3 pound of ammonium nitrate
or its equivalent for each year of age.

Urea

0.7

1.3

Ammonium nitrate

0.9

1.8

Sodium nitrate

1.9

3.8

Calcium nitrate

1.9

3.8

5-10-10

6.0

12.0

8-16-16

3.8

8.0

10-20-20

3.0

6.0

-9-

Reduce or omit N on young, vigorous Mcintosh trees when they start to bear fruit,
if the trees appear very vigorous, to avoid excessively large, poorly colored apples.
With this cultivar and all other cultivars, start participating in the Leaf Analysis
Program when the trees start to fruit in order to determine the fertilizer requirements
of the trees. (Information concerning the Leaf Analysis Program and specific details
on orchard fertilization can be obtained from your County Extension Service.)

Bearing trees. There is no way to go broke faster than by producing high yields of
soft, green apples that bruise easily and keep poorly. On older, bearing Mcintosh trees,
N levels of 1.8 - 2.0% appear optimum. If the leaf analysis shows that the N level
is above 2.0%, adjust the fertilizer program according to tree vigor, productiveness
and fruit color, as experience indicates. High leaf N levels fall very slowly even when
no additional N fertilizer is supplied because large reserves of the element accumulates
in the soil, sod and tree. Therefore, it may take several years to bring an excess N
level down to the normal level.

Our data shows that the total amount of N being applied is usually more important
concern to fruit quality than whether the N is supplied by applying ammonium nitrate,
sodium nitrate, calcium nitrate, etc.

Fertilizer Placement Under Bearing Trees. The mass of the secondary root system
of apple trees lies between 2 and 3 feet in depth and within half the distance from
the tree trunk and its dripline. This explains why our studies show that more efficient
use of N and other elements can be obtained by application within a limited area closer
to the tree trunk rather than by application near the tree's dripline or a broadcast
application under the entire spread of the tree. Recent studies in England show that
under herbicide-strip management and with a wide in-row spacing, as in common in
Massachusetts, there was little N uptake from the grassed alley.

POTASSIUM (K)

Generally N is the only element required by non-bearing trees. However, experience
has shown that K is needed by non-bearing trees on land cleared from forests and on
sites with sandy or gravelly soil, or very acid soil.

Not all horizons in the soil are equally able to supply nutrients to the tree. The
concentration of most elements are highest at the soil surface and decrease with
depth, but the rate of decrease differs between elements. For example, there is a
strong vertical difference in K status in soil, K being highest near the surface.

Under drought conditions the permeability of the roots to water uptake decreases
very rapidly; reduction in water permeability reduces the uptake of all ions. In Massa-
chusetts we are particularly concerned about K and B deficiency and reduced fruit
size in drought years as was experienced during the summer of 1983.

Total K absorbed and the total dry matter produced is similar for fruiting and non-
fruiting trees of the same size but in heavy-cropping trees K is translocated into the
fruits. Thus, the demand of a larger crop for K is great and both the tree and fruit
may be deficient in this element.

-in-

Tree requirements for K. K„0* needed to meet the K requirements based on potential
yields are as follows: (a) less than 15 bushels: 1.3 lbs/tree; (b) 15 to 25 bushels: 1.3
- 2.7 lbs/tree; and (c) more than 25 bushels: 2.7 - 4.3 lbs/tree. The K„0 requirements
can be supplied by applying muriate of potash, a "complete" fertilizer or Sulpomag**.
Increasing the K level in the trees will further reduce IVIg. Therefore, Sulpomag is
suggested when trees are low both in K and Mg because the elements must be kept
in balance. This fertilizer contains not less than 21% of potash (K2O), nor less than
53% of sulfate of magnesia. Mature trees below normal in K will require 200-300
of K or 600 lbs of Sulpomag per acre. FERTILIZERS SIMILAR TO SULPOMAG MAY
BE AVAILABLE AND EQUALLY SUITABLE.

CALCIUM (Ca)

If Ca is below normal, continue to apply 3 tons of limestone per acre every 2 to
3 years. Where high magnesium lime was used in the last application, the use of a
more soluble high Ca, low Mg lime (5 - 7% MgO) will act more rapidly and will provide
more Ca.

Apply foliar sprays of CaCl2, beginning 3 weeks after petal fall and repeat at 2
week intervals totaling 6 to 8 applications. Apply 6 pounds CaCl2 per acre per spray
until mid-July. After mid-July apply 8-10 pounds per acre per spray. Continue foliar
CaCl2 until fruit are ready for harvest. Use a technical grade of CaCl2 such as Allied
Chemical Dow Flake, 77-80% CaCl2. Other brands may be equally suitable.

Experience in Massachusetts has shown that CaCl2 can be combined with pesticide
sprays. However, some growers have observed that the combination of Captan or
Guthion (azinphosmethyl) 50 WP and CaCl2 may increase foliar burn. DO NOT MIX
CaCl2 AND SOLUBOR SPRAYS! ALWAYS DISSOLVE CaCl2 IN A PAIL OF WATER
and add this last, when the spray tank is nearly full, to insure that the CaCl2 is
completely dissolvedbefore spraying begins.

Foliar CaCl2 sprays may be applied as dilute (300 gallons/acre) or up to lOX
concentration (30 gallons/acre) . In our research, apple flesh Ca was increased more
by concentrated than by dilute sprays.

CaCl2 sprays can cause burn of leaf margins. Foliar injury has been more serious
on Mcintosh than on Delicious or Cortland. Apple leaves are less susceptible to CaCl2
burn after mid-July. Mcintosh growing on M7 may be more susceptible to foliar burn
than those on standard rootstock. Weak or injured trees may be more susceptible to
CaCl2 burn than healthy trees. To reduce the chance of leaf burn, DO NOT REPEAT
A FOLIAR CaCl2 SPRAY UNLESS ONE-HALF TO ONE INCH OF RAIN HAS FALLEN
SINCE THE LAST APPLICATION.

We also urge growers to seriously consider supplementing CaCl2 sprays with
post-harvest CaCl2 dips or drenches especially fruit intended for long-term storage.
A postharvest Ca application is viewed as a food-additive process by the Food and Drug
Administration. That agency has stipulated the "Brining Grade" CaCl2 containing 94%
CaCl2 is acceptable for postharvest use. The technical flake CaCl2 commonly used
for tree sprays is still acceptable for tree sprays, but it may not be used for postharvest
treatments. Therefore, anyone wishing to use postharvest CaCl2 treatments must obtain
the Briner's Grade material, which is now readily available from suppliers.

*
Potassic fertilizers are usually guaranteed in terms of their content of the oxide of

potassium (K2O). The commonly used potash salts are the refined muriate or chloride

containing 50-60% K2O.
**

Trade name

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Calc2 may be combined with scald inhibitors and fungicides in the post-harvest
treatment solution. Cornell University has recommended the following mixture for
postharvest treatment of Mcintosh:

21 lbs of CaCl2 per 100 gallons of water

1/2 lb of Benlate or 16 fluid ounces of Mertect

1 lb of Captan

1000 - 2000 ppm DPA

We suggest that 1/2 quart of vinegar also be added to this mixture in 100 gallons
of water. The vinegar neutralizes the CaCl2, which otherwise makes the solution
alkaline. There is evidence that the alkaline solution may cause the fungicides to
break down rapidly in solution, and the addition of vinegar can protect against their
alkaline degradation.

In use of postharvest CaCl2 drenches or dips, it is important to understand that
little or no Ca enters the fruit during the treatment. The purpose of the drench is
to leave a residue of CaCl2 on the fruit. Ca is slowly absorbed by the apple from
the residue during storage. Therefore, the drench is never followed by a rinse, which
would remove the residue. Furthermore, for Ca to be absorbed from the residue, the
residue must not dry out. However, if the storage is operated at lesss than 90% relative
humidity the residue may dry out and no Ca uptake will occur as a result of the drench
treatment.

We have encountered no difficulty from this residue when apples are removed from
storage. It will be removed if apples are water-dumped, but even with hand-packed
fruit no difficulty has been reported.

CaCl2 drenches can cause fruit injury, which occurs as tiny black spots on the surface
of the fruit. Generally, these spots are concentrated in the calyx cup of the apple
and are not objectionable, although under some circumstances they may coalesce into
more unsightly blotches or may occur at the lenticels on the cheeks. Do not exceed
the recommended CaCl2 concentration, as risk of this injury escalates rapidly at higher
concentrations.

CaCl2 is also corrosive, so equipment should be thoroughly cleaned at completion
of treatment. However, with appropriate rinsing corrosion should not be a concern.

The purpose of the postharvest application of CaCl2 is to reduce the risk of
breakdown, rot, and scald during but especially after storage. The recommended
treatment will not make fruit firmer, but will improve their ability to hold up during
marketing. Treatments will be of greatest benefit to mature fruit destined for long-term
storage. Overripe fruit cannot be expected to benefit significantly from a CaCl2
treatment.

MAGNESIUM (Mg)

Mg deficiency is closely associated with very acid soils. The pH in most orchards
is higher than 25-years ago because liming programs and the change from sulfur to
organic fungicides; thus, Mg deficiency is now not common.

Dolomitic lime (high Mg lime) is the least expensive source of Mg for orchards.
It can be applied anytime during the year. If the Mg level in leaves is below 0.25%
apply 3 tons/A of dolomitic lime to maintain a soil pH of 6.0 - 6.5. If the Mg level
is below 0.20%, we also recommend 2 or 3 Epsom salt sprays at 15 to 20 lbs per 100
gallons dilute at approximately petal fall, first, and second cover. We suggest that
the Epsom salt sprays be applied as separate applications. However, pomologists in
other fruit growing areas in eastern United States believe that Epsom salts are
compatible with most pesticides up to 15X concentration.

12-

MANGANESE (Mn)

Mn is the most frequently deficient element in apple trees. Mn deficiency should
be corrected on trees showing considerable foliage damage. Although we have no
definite proof, Mn deficiency appeared to be associated with excessive fruit drop
on a few trees in orchard in 1977. Mn deficiency can be corrected by foliar applications
of manganese sulfate or of a fungicide containing Mn. Apply manganese sulfate at
about first cover at the rate of 3 lb per 100 gallons of water. If using a Mn-containing
fungicide, 2 or 3 applications are necessary with timings about petal fall, first and
second cover.

BORON (B)

B can be supplied to bearing apple trees either by foliar or soil applications. Use
the most economical and convenient method. However, it is safest to apply all elements
as a fertilizer except in emergency situations.

Soil applications of boron should be applied to orchards every 3 years. The rate
of application per tree vary with tree age and size. In low density orchards, apply
1/4 lb of borax (11.1% actual B) or its equivalent under young trees coming into bearing,
1/2 to 3/4 pound to medium age and size trees and 3/4 to 1 lb to large or mature trees.
Be sure to note the percent actual B in the fertilizer being used to supply this element.
B containing fertilizers vary from approximately 11 to 21% actual B.

In medium and high density orchards (115 trees/acre or higher), it might be best
to apply B on an acre basis. We suggest the following rates per acre of borax (11.1%
actual B) or its equivalent: (a) trees 4 to 7 years of age - 12 lbs; (b) trees 8 to 15 years
of age - 12 to 24 lbs; and (c) trees 16 to 30 years of age - 24 to 48 lbs.

When the soil application of B is followed by a wet spring, it may be advisable to
apply 2 foliar applications of B the following year.

Many growers now rely on annual foliar applications of B. The usual practice is
to add Solubor to the first 2 cover sprays. Fertilizer grades of borax may contain
grit and should not be used in a sprayer. Mature trees should receive 4 pounds of Solubor
per acre each year. Consequently, the goal is to apply about 2 pounds per acre in each
of the 2 applications. For young orchards, the addition of 1/2 pound of Solubor per
100 gallons (dilute basis) to the first 2 cover sprays meets the B requirements of these
trees. Reports of New York State indicate that sprays can be concentrated up to 8X
with satisfactory results.

Leaf samples from orchards treated with Solubor have indicated adequate leaf
B levels but the fruit was deficient in this element. Whether or not B applied as a
fertilizer more adequately meets the B requirement of apples than foliar applied B
is not known to us.

ZINC (Zn)

Based on optimum levels of Zn established by Dr. Warren Stiles, Cornell University
(See FRUIT NOTES 47(2):20-26, 1982) some of our orchards continue to be low in this

-13-

element. W. Stiles considers optimum Zn leaf levels to be 35 - 50 ppm with
concentrations below 15 ppm being deficient. He has stated that "annual requirements
for Zn are approximately 2 lbs per acre if applied as inorganic salts in dormant sprays
or approximately 0.2 - 0.3 lbs of actual Zn applied as foliar sprays of EDTA chelates
IT to 5 lbs/acre). Amounts of Zn required to correct severe deficiencies may be 4
to 5 times these amounts. Zn-containing fungicides provide some benefit but are not
adequate to supply the total need."

CARE OF TREES ON ARRIVAL FROM THE NURSERY

William J. Lord
Department of Plant and Soil Sciences

A local nurseryman expressed concern last year about grower care of trees prior
to planting. He was particularly concerned with storage of trees with apples and about
soaking trees in water for 2-3 weeks.

If trees from the nursery arrive in bad condition from drying in transit, pomologists
years ago suggested soaking the entire tree in a brook or a pond for a day or two. We
have seen no comments concerning the effect of soaking trees for longer periods of
time! Due to the possibility of tree injury from the lack of oxygen, we suggest soaking
the roots in water no longer than a day or two.

Our recommendations for care of trees on arrival from the nursery are as follows:

1. Check the trees to determine if tree count and cultivar/rootstock and size agrees
with order and to determine if injury to the trees might have occurred in handling
and shipping. Do this where it is cool and the roots will not dry out.

2. If planting conditions are not suitable, open the bundles of trees and store them
in a cool, well-ventilated area and be sure the roots are kept moist, or heal them
in a shady area, or cover the roots with wet soil, peat or sawdust in an open shed.

3. DO NOT STORE trees with apples or where they have been stored. It is possible
that residual ethylene in the storage atmosphere might break dormancy of the trees
and when planted they may fail to grow properly or even die. Pear trees are especially
sensitive to injury.

4. If the roots of the trees are dry, soak the roots in water for 2-24 hours prior to
planting.

-14-

PRACTICALITY AND LONGEVITY OF HARDPAN MODIFICATION

Peter L.M. Veneman
Department of Plant and Soil Sciences

About 40% of the soils in Massachusetts have a hardpan within 3 ft of the soil surface.
Considering the fact that a large number of our orchards are located on drumlins
(elongated or oval hills of glacial drift), I estimate that between 50 to 60% of the
Massachusetts orchard soils have a hardpan within 3 ft depth. The presence of this
pan is well known to most fruit growers as it often necessitates sub-surface tile drainage.
The low water permeability is due to a high bulk density of the pan material. This often
inhibits root proliferation as well, which may result in increased susceptibility to
midsummer droughts and excessive frost heaving during the winter.

Modern, size-controlling rootstocks seem especially sensitive to the presence
of this hardpan. The dwarfing effect not only occurs above-ground, but is also evident
from a less prolific root system as compared to that of standard rootstocks. In addition,
size-controlling rootstocks such as M7a are in full production after about 10-12 years,
while the standard trees take much longer to become productive. The longer time period
permits the establishment of an extensive root system before this becomes strained
under the demands of a maturing fruit crop. Even though economic conditions dictate
the need for early production, tree vigor and the need to sustain long-term production
capacity necessitate the establishment of a healthy and extensive root system prior
to the onset of production.

This article reviews the pertinent literature concerning the long-term persistence
of soil profile modifications and discusses practical methods which may improve root
vigor of fruit trees in hardpan soils.

A variety of experiments have been carried out in past years to evaluate the effects
of soil profile modification on drainage, water availability, frost heaving and crop yield.
In general, the deeper and more extensive the initial soil disturbance is, the better the
results (Unger 1979). Various experiments (Mech et al. 1967, Bradford and Blanchar
1977) found that mixing the top soil with sub-surface layers, and additions of lime,
fertilizer or even sawdust significantly increased yields of alfalfa and sorghum. It is
reasonable to assume that such an improved growth environment also will foster the
development of fruit trees, both above and below ground. Recent research reports
(Unger, 1979) stress the importance of mixing the topsoil with the subsoil to obtain lasting
results. Studies in New York indicated that modification of a hardpan by mechanical
disturbance alone, resulted in re-establish ment of dense soil layers in less than 11 years
while buried topsoil remained less dense even after that period (Fritton and Olson, 1972).
Researchers in Pennsylvania found that additions of organic matter wiU delay the
soil's return to its original bulk density for a period of 7 to 8 years (Fritton et al. 1983).
That study also reported the ineffectiveness of subsoiling and deep tillage when the
topsoil was not mixed with subsoil.

The use of topsoil from old orchards for new plantings may be less desirable when
the soil is suspected to contain large numbers of nematodes. Thorough mechanical
mixing may reduce the nematode population susbstantially (R. Rohde, personal
communication). Use of non-orchard topsoil, hay or peat will prevent a nematode problem
and give the young trees a head start, although this method probably is more costly.

-15-

A comparison of various apple planting methods in West Virginia (Auxt et al.,
1980) showed that tree vigor was best when procedures were used which resulted in
a large disturbance of the soil. Trees planted by backhoe or tree planter were most
successfully established, while a conventional 24" soil auger resulted in less tree vigor
and anchorage. It was found that use of 12" or 24" augers resulted in significant soil
compaction, which negatively affected tree growth. The West Virginia soils contained
more clay than most Massachusetts orchard soils, but smearing of the soil can be a
significant problem in this region as most of the trees are planted during early spring
when the soil often is extremely wet.

While the long-term effects of soil profile modification are debatable, the
short-term benefits are beyond doubt. These include improved drainage, aeration and
water holding capacity, and less problems with frost heaving. When planting fruit trees
it is generally a good practice to make the planting hole as large as possible. When
the soil contains a hardpan at shallow depth this procedure is even more important to
provide the tree with an environment for optimum growth. Mixing topsoil with the
subsoil, and additions of lime, fertilizer and organic matter such as hay and peat, will
prolong the effect of soil profile modification and thus lengthen the period of root
prolification. Smearing of the soil should be prevented, but is especially important
when augers are used. When smearing in the borehole is evident, remove the smeared
surface with a knife. Never plant the trees in waterlogged planting holes. Wait until
the soils dry out or plant the trees in the fall. If excessive wetness is a reoccuring
problem at the future planting site, ensure proper drainage first and select rootstocks
which can endure wet feet. Anybody can plant a tree. Planting of a tree which will
last and prosper takes considerable time and care.

References Cited

1. Auxt, T., S. Blizzard, and K. Elliott. 1980. Comparison of apple planting methods.
J. Am. Soc. Hort. 105:468-472.

2. Bradford, J.M. and R.W. Blanchar. 1977. Profile modification of a Fragiudalf to
increase crop production. Soil Sci. Soc. Am. J. 4:127-121.

3. Fritton, D.D., and G.W. Olson. 1972. Bulk density of a fragipan soil in natural and
disturbed profiles. Soil Sci. Soc. Am. Proc. 36:686-689.

4. Fritton, D.D., F.N. Swader, and K. Hoddinott. 1983. Profile modification persistence
in a fragipan soil. Soil Sci. 136:124-130.

5. Mech, S.J., G.M. Horner , L.M. Cox, and E.E. Cary. 1967. Soil profile modification
by backhoe mixing and deep plowing. Trans. Am. Soc. Agri. Eng. 10:775-779.

-16-

THE APPLE MAGGOT IN MASSACHUSETTS, MICHIGAN AND WEST COAST STATES

Ronald J. Prokopy
Department of Entomology

Massachusetts apple growers are all too familiar with the apple maggot and the
type of fruit injury that this pest can cause. During our pilot integrated pest management
(IPM) program on apples in Massachusetts from 1978-1982, we used sticky-coated red
wooden spheres to monitor the time and extent of maggot activity in 16-60 commercial
orchard blocks each year. Without exception, at least a few maggot flies were captured
annually in each block. In some cases, several hundred were caught in a single block.

Our experience shows that 99.9% or more orchard maggot fly populations in
Massachusetts originate from wild or abandoned host apple or hawthorn trees within
a few hundred yards of the orchard. On only 2 occasions have we found maggot flies
emerging from within a commercial orchard itself. In both of these, maggot-infested
early-maturing varieties such as Puritan and Astrachan were not harvested the previous
year.

Despite the continuous pressure that maggot flies exert on our Massachusetts
orchards, only 0.08 and 0.09% of harvested fruit showed maggot injury in IPM and check
orchards, respectively, during the 5 years of the pilot IPM program [see FRUIT NOTES
48(3)]. The principal reason for this comparatively low fruit injury is the high sensitivity
of the adults to even low dosages of pesticide. Moreover, as shown by the work of Dr.
Harvey Reissig of Geneva, New York, some pesticides such as Guthion are highly effective
not only against the adults but also kill the eggs and young larvae, just beneath the
fruit skin.

Our experience reveals that so long as growers rely on red sphere trap captures
to determine need and timing of maggot fly sprays, there is very little chance of any
injury occurring. Most of the maggot injury detected in Massachusetts has been on late
varieties such as Delicious and Golden Delicious in cases where substantial fly
immigration occurred 2 or more weeks after spraying ceased for the year.

Michigan apple growers in 1983 experienced more apple maggot injury than at
any time during the past 2-3 decades. According to Michigan fruit entomologist Dr.
Gus Howitt, fruit of late varieties such as Jonathan had more than 5% maggot injury
in many orchards. Dr. Howitt told me that hundreds of thousands of bushels have been
rejected for fresh fruit market and for processing because of excessive maggot injury.

Dr. Howitt attributed the severe maggot problem in Michigan in 1983 to the very
dry summer, which precluded summer emergence of flies from overwintering pupae.
Emergence didn't begin in full force until just after heavy rains in late August and early
September. By that time, most of the summer-maturing fruits on wild or abandoned
trees had fallen, thereby stimulating extensive immigration of flies into commercial
orchards. The warm September was favorable for fly egglaying in late varieties. Also,

-17-

red spheres were used by only a handful of Michigan growers to monitor fly activity,
and most spraying had ceased by early to mid-August. This combination of events
undoubtedly explains the maggot fly problem which occurred in Michigan. It should
serve as a reminder to us that the comparatively little effort required to emplace and
examine red spheres for monitoring maggot fly abundance can pay very large dividends.

Eastern and midwestern growers are not the only ones who must be concerned
with apple maggot. In 1979, a homeowner near Portland, Oregon brought some rotting
apples to the local extension service which were diagnosed as being heavily infested
with apple maggot larvae. Subsequent trapping and fruit injury surveys on the west
coast showed that apple maggot is more or less continuously distributed from southern
Washington to northern California. Numerous wild apple and hawthorn host trees in
presently infested areas appear capable of supporting substantial fly populations.

Just how far the fly can penetrate into the major apple growing regions around
Yakima and Wenatchee in Washington is uncertain. The very dry summers in the
Washington state fruit growing areas coupled with the relatively low numbers of wild
host trees, are factors arguing against the widespread establishment of apple maggot
much beyond the northern border of Oregon. Nonetheless, a concerted and expensive
effort is now underway to maintain a buffer (fly-free) zone around the present infestation
area in Washington to prevent any further northward movement. The buffer zone, about
15 miles wide, is trapped heavily (50-80 traps per square mile) for maggot flies. Imidan
is sprayed extensively in locales surrounding sites of trap captures. In addition, there
is an intensive host tree removal program within the buffer zone.

In Oregon, the apple maggot is now so entrenched (it may have been there,
undetected, for 10-20 years prior to 1979) that no feasible means exists of exluding it
from the vicinity of any of the apple growing areas. However, buffer zones, similar
to those in Washington, have been erected immediately around certain locales of intensive
apple growing, such as the Hood River Valley.

Possibly California apple growers believed the fly would never be so bold as to
move south across the Oregon border. But on August 24, 1983 the first flies were detected
in traps about 50 miles into California. Within 2 months, the area of known infestation
reached about 150 miles south into California. Actually, it shouldn't be surprising that
the apple maggot was found in California. During the past 30 years apple maggot (in
the form of larvae in infested fruit) was intercepted by Border Station Inspectors more
often than any other insect pest entering that state.

In mid-October, 1983 1 was asked to chair a panel of scientists to go before officials
of the California Department of Agriculture, growers, and the public to make
recommendations as to what to do about this "sudden" invasion of the fly. Because
of the near hysteria caused by the Mediterranean fruit fly invasion of California in
1981, 1 was very reluctant to accept this charge. But it proved to be a highly informative
and relatively calm experience.

Our panel concluded that the apple maggot fly had probably been in California
for at least 5 years. Scouts were finding it nearly everywhere they looked, although

-18-

never in very large numbers at any one site. Possibly the apple maggot will have
difficulty building into high populations in more southern regions such as California.
At present, its southernmost distribution lies only a hundred miles or so north of one
of the major California apple producing areas.

For several biologically-based reasons, our panel concluded that it was virtually
impossible to eradicate the apple maggot from California, given its already widespread
distribution in that state and neighboring Oregon and given the fact that a major part
of the present area of infestation lies in the heart of the California marijuana growing
region. Marijuana is the largest "agricultural" crop of California, even exceeding cotton,
and is worth more than 1.3 billion dollars per year. It is very dangerous for state
employees to explore terrain within this region (often laden with land mines to deter
unwanted visitors) to seek out maggot flies and host trees to eradicate. Hence we
recommended adoption of buffer zone procedures similar to those used in Washington
and Oregon. Whether this recommendation will in fact be adopted remains to be seen.

Thus, 1983 was a big year for the apple maggot in Michigan, Washington, Oregon,
and California. We are fortunate that 1983 was not a problem year for apple maggot
in Massachusetts.

Gala - An Apple Variety Worthy of Trial

James F. Anderson
Department of Plant and Soil Sciences

Gala, a variety from New Zealand has been receiving much favorable attention.
This variety resulted from a cross between Kidd's Orange and Golden Delicious and
was introduced in 1960. We have fruited Gala for 4 seasons. The fruit has been medium
to large in size on these trees planted in 1978. The fruits are generally round-conic
in shape. The skin is smooth and the color golden-yellow overlaid with about 80% red.
The flesh is yellow crisp and has a very good flavor. The fruit in our Belchertown orchard
has been harvested during the second and third week of September, the fruit hangs well
on the tree. The fruit stores well for a fall apple. Gala appears to be a productive
variety and merits trial by those growers operating farm markets.

-19-

THE USE OF PROMALIN TO IMPROVE THE SHAPE OF DELICIOUS APPLES

Duane W. Greene and William J. Lord
Department of Plant and Soil Sciences

Promalin is a plant growth regulator that has been used for several years in
Massachusetts orchards to increase the length (L/D ratios or typiness) of Delicious apples
(Figure 1). Promalin contains equal amounts of gibberellins (GA4 and GA7) and a
cytokinin, 6-benzyladenine. We previously reviewed research results and made suggestions
for the use of Promalin (FRUIT NOTES 43(3):4-7, 44(3):4-8 and 45(3):8-12). The purposes
of this article are to summarize results from several years of research results with
Promalin, and to make suggestions for successful use of Promalin to enhance the shape
of Delicious.

Figure 1. The effect of Promalin on shape of Delicious apples. The apple on the left
was treated with I2 pt Promalin per acre and the one on the right was
unsprayed.

Coverage. When using plant growth regulators it is generally emphasized that uniform
spray coverage is essential for satisfactory results. This is especially true when using
Promalin. In both 1978 and 1979 the greatest increase in L/D ratio occurred only when
Promalin came in direct contact with the portion of the flower that develops into the
fruit (receptacle and calyx end of the receptacle). Application to the pedicel (stem)
was much less effective (Table 1).

-20-

Table 1. Effect of the site of Promalin application on the L/D ratio of Richared
Delicious apples.

Treatment^

L/D Ratio*

(Microliters)

1978

1979

Check

0.93cX

0.91c

Petals, 25y

0.94c

0.91c

Petals, 150

0.99b

Receptacle surface.

1.03a

In Calyx end,

, 25

1.03a

1.04a

Pedicel, 25

0.97b

Spur leaves.

250

0.90c

^50 ppm solution containing 0.05% X-77 applied at fullbloom. All blossom clusters
reduced to one flower and then hand-pollinated with Early Mcintosh pollen.

YA 25 microliter droplet was large enough to wet the receptacle or pedicel surface
with no runoff.

'^Numbers in a column followed by a different letter are significantly different at odds
of 19 to 1.

Petals at the normal application time account for a substantial portion of the flower
surface area. However, they appear to be relatively unimportant as a vehicle for
absorption. Even 150 pi applied to the petals (the volume comparable to a dilute
application) was only moderately effective at increasing the L/D ratios. Spur leaves
were totally ineffective as sites of Promalin absorption. Therefore, not only must
Promalin be directed uniformly to all parts of the tree but droplets must also come
in direct contact with the receptacle of each flower for the maximum response.

Use of surfactants and adjusting pH of spray solution. Surfactants frequently increase
the penetration of growth regulators. However, the use of surfactants is generally
not recommended with growth regulators, since most formulated growth regulators
(e.g.. Alar 85, Fruitone N, e.tc.) already contain a surfactant. In contrast, the Promalin
formulation contains no surfactant, so we thought that the use of a surfactant with
Promalin might increase the Promalin effect on fruit L/D ratio. In addition, the ability
of gibberellins to enter the plant may be regulated by spray pH. Reduction of the pH
of the spray from near neutrality (pH 7.0) down to near pH 4.0 should enhance penetration,
but field effects have not been well documented.

A trial was conducted using a combination of surfactants and a reduction in spray
pH was done on Royal Red Delicious. Glyodin, Biofilm and Buffer-X served as surfactants
and the pH was reduced in 2 treatments with the nutrient spray Sorba Mg. Buffer-X
contains a buffer to reduce pH (pH 4.8 in this trial). The combined sprays of a surfactant
with the commercial buffer tended to increase the L/D ratio beyond that produced
by Promalin alone (Table 2). Growers must be cautioned, however, that the enhanced
response with surfactants and/or buffers also increase the chance of thinning.

L/D = Length/diameter ratio. An apple with an L/D ratio of 1.04 is longer and more
"typey" than one with a ratio of 0.90.

-21-

Table 2. The effects of surfactants and pH modification on the performance of
Promalin applied to Royal Red Delicious, 1978.

Treatment^

Fruit

per cm

weight

limb circ.

L/D ratio

fe)

Check

7. lay

0.95c

154abc

Promalin

G.Oab

1.00b

142b

Promalin + Sorba (Mg)+

Glyodin

4.9bc

1.04a

146bc

Promalin + Sorba (Mg)+

Biofilm

4.8bc

1.03a

156ab

Promalin + Buffer-X

4.1c

1.02ab

161a

^l pt of each chemical was used per 100 gal. of water. Treatments applied at
rate of 125 gal/acre at petal fall of the king blossom.

yNumbers in a column followed by different letters are significantly different at
odds of 19 to 1.

Fruit set following Promalin application. Within 2-3 days following a Promalin appli-
cation, calyx swelling and closing is apparent, first on the king blossom and then on
lateral blossoms. Promalin merely accelerates that which normally occurs on pollinated
flowers. Ten to 12 days after application, Promalin appears to have increased fruit
set. However, about 15 days after bloom, yellowing of the pedicels occurs on many
of the developing fruit in the cluster. By 3 weeks after bloom most of the less vigorous
fruit have dropped and within 4 weeks after bloom fruit set has been determined and
subsequent drop is minimal.

Thinning due to Promalin application. It is well documented that Promalin can thin.
However, in most cases where Promalin has thinned, label directions were not followed.
Causes of thinning include:

1. Overapplication. The most frequent cause of thinning due to over-application is
poor sprayer calibration. Portions of a tree also may be overthinned due to poor
spray distribution within the tree. Lower, weaker spurs thin more easily than more
vigorous spurs located in the tops of trees.

2. Application during hot weather. If Promalin is applied when temperatures exceed
85°F, the likelihood of thinning is dramatically increased.

3. Application on young trees. Treatment of young trees frequently results in complete
removal of the crop. This is particularly detrimental on young Delicious trees just
coming into bearing since even a small crop is quite useful to bring down branches,
help slow growth and encourage consistent fruiting.

Nevertheless, thinning due to Promalin may also be more apparent than real. Pro-
malin may merely accelerate young fruit abscission that would normally occur during
the early 'June-drop' period. It would certainly appear that Promalin was increasing
thinning if you assessed fruit set 2-3 weeks after bloom. However, in most situations,
it appears that Promalin has advanced the 'June-drop' by about 2-3 weeks, thus giving
only the impression of thinning. While Promalin can indeed cause thinning, caution
should be exercised in concluding that this has happened on your trees.

-22-

Use of chemical thinning following Promalin application. Promalin applied by itself is
capable of thinning. A chemical thinner, generally Sevin, is often used during the
post-bloom period on Delicious. Frequently, increased thinning is observed when 2
different thinning agents are applied. Therefore, it is particularly important to know
if Promalin-treated trees are thinned to a greater extent than unsprayed trees when
chemical thinners are applied. We have attempted to answer this question with 5 different
experiments over the past 4 years using both Sevin and NAA as chemical thinners. Results
of a typical experiment are shown in Table 3. When applied as a dilute spray during the
bloom period, Promalin thinned. Sevin thinned Promalin-treated or untreated trees
comparably. In no experiment did the combination of Promalin with either chemical
thinner reduce the crop load below that on trees treated with either Promalin or the
chemical thinner alone. Very 'typey' fruit with large L/D ratios were harvested from
both Promalin and Promalin-plus-chemical thinner trees.

Table 3. Effect of Promalin, Sevin, and naphthaleneticetic acid (NAA) on fruit set, fruit characteristics anc
yield of Double Red Delicious apples.
1982.

Blossom

clusters/

cm limb

circum.

1982

Fruit

Fruit
wt.

(g)

L/D
ratio

Seeds/

fruit

Treatment^
(ppm)

per cm

limb
circum.

per 100
blossom
clusters

Yield
(bu/tree)

Check

10.1a

7.6ab

75.7b

169a

0.96b

6.3a

11.0a

Promalin 25

10.1a

5.1c

56.3bc

179a

1.04a

5.6b

8.9b

Promalin 25 +

Sevin 1200

9.9a

A.lc

/i0.3c

176a

l.OAa

4.5c

6.1c

Promalin 25 +

NAA 6

9.6a

6.3bc

66.9b

123b

1.03a

1.7d

7.2bc

Sevin 1200

9.0a

ii.lC

55.0bc

176a

0.96b

4.0c

6.5c

NAA 6

9.6a

9.1a

100.7a

122b

0.93c

1.9d

6.8bc

^Promalin applied 5/12/82 (full bloom 5/13/82) as a dilute spray with 1 pt/100 gal. Glyodin. Sevin and NAA
applied as a dilute spray on 5/30/82.

Weather conditions following chemical thinner application were cloudy and moist
thus favoring foliar penetration. Complete drying of spray droplets did not occur for
24 hours. Trees treated with NAA soon showed typical leaf epinasty (twisting) and the
development and retention of many small and seedless 'pygmy' fruit became apparent.
It is for this reason that NAA appears not to have thinned and that average fruit size
on these trees was considerably smaller (Table 3). Although 'pygmy' fruit were observed
only one year, this illustrates the potential danger of using NAA as a chemical thinner
for Delicious.

It should be noted that Promalin did not increase fruit weight (Table 3). We have
never observed an increase in fruit size following Promalin application unless the treatment
caused significant thinning. The increase in fruit length caused by Promalin was
accompanied by a corresponding reduction in fruit diameter. The reduced fruit diameter
is attributed to a reduction in seed number.

-23-

Uniformity of Promalin response on the tree. The L/D ratio of fruits will vary considerably
on a tree. This is due to the location of the fruit on the tree and their origin within the
blossom cluster. The L/D ratio distribution of fruits from untreated and Promalin-treated
trees is similar (Figure 2). This indicates that a Promalin application increases the L/D
ratio of all fruits on the tree equally. Therefore, a grower can expect to find some rather
flat-looking Delicious on Promalin-treated trees at harvest time although there should
be fewer than on check trees.

I .20

Figure 2. The L/D ratio distribution of fruits from trees receiving a 25 ppm dilute spray
of Promalin and from Control trees.

Variable Promalin response. It has been observed that the L/D ratio following Promalin
application is sometimes less than expected. We believe that there are at least two
reasons for this. Weather, and especially high temperature during and following the
bloom period, can influence fruit shape. Undoubtedly, part of the diminished response
can be attributed to high temperature during and following Promalin application. It
is known that temperature during and following bloom can have a direct effect on cell
division and expansion in the calyx end of fruit. Based upon several experiments over
several years where Promalin was placed directly in the calyx of fruit it is concluded
that Promalin always elongates fruit. Promalin promotes at least 2 independent processes:
fruit elongation and fruit thinning. In situations where a diminished response is observed,
Promalin may be thinning from the cluster the fruit that have been elongated.

-24-

Effect of Promalin on pollinizers. Delicious is not the only cultivar that can be elongated
with Promalin. If pollinizers are located within the rows of Delicious being sprayed you
can expect elongation of these fruit also. Increased length of such cultivars as Mcintosh
and Cortland in most cases would not be desirable. Therefore, when applying Promalin
attempts should be made to avoid spraying pollinizer trees where increased calyx-end
length is not wanted.

Suggestions for Promalin use

1. Calibrate your sprayer. Thinning due to Promalin has often been traced to
overapplication because of improper sprayer calibration and nozzle adjustment. The
margin of error with Promalin is not great. The label suggests that Promalin should
be applied in 100-200 gal/acre. Therefore, an error in application of only 50 gal/acre
can result in a 50% increase in the amount of Promalin applied.

2. Do not apply more than \i pts/acre of Promalin.

3. Do not apply Promalin when the temperature exceeds 85° F. Excessively warm
temperatures may increase the thinning response without a corresponding increase
in the shape response.

4. Do not apply Promalin on young trees. A good rule-of-thumb is not to apply this
growth regulator on any tree until it is bearing heavily enough to consider chemical
thinning.

5. Apply Promalin as soon after opening of the king blossom as weather permits. This
is earlier than we have suggested in the past. It is our feeling that the reduced leaf
surface at this earlier timing may reduce the possibility of thinning.

6. The addition of surfactants or spreader stickers increases both the fruit shape and
thinning response to Promalin. On trees where bloom is heavy and the use of a chemical
thinner is anticipated, the addition of a surfactant or spreader sticker is suggested.

7. Promalin may thin as well as accelerate the normal fruit abscission process. Therefore,
before using a chemical thinner on Promalin-treated trees, check initial set to see
if additional thinning would be desirable. It is possible that no chemical thinner is
needed on Promalin treated trees. If a thinner is used on Promalin-treated trees
it is unlikely that thinning will be excessive.

8. Leave a few untreated and representative trees in the Promalin-treated block. Initial
fruit set, subsquent drop and fruit shape are never constant from year to year.
Therefore, the only way to accurately assess the performance of Promalin in your
orchard is to leave a few untreated trees in the same block to indicate what would
have happened in the absence of the Promalin spray.

-25-

FREEDOM: A NEW DISEASE-RESISTANT APPLE

William J. Manning and Daniel R. Cooley
Department of Plant Pathology

The New York State Agricultural Experiment Station at Geneva has released a
new disease-resistant apple named Freedom. The new cultivar is described by Professor
Robert C. Lamb, Freedom's originator, as a "very productive, large attractive apple
of good quality that can be used either for the fresh market or for processing." Like
Liberty, Freedom (formerly NY58553-1) is immune to apple scab and moderately
resistant to powdery mildew, but slightly less resistant to cedar apple rust and fire
blight than Liberty.

Freedom blooms at midseason in Geneva and has been shown to be a good pollen
source for other cultivars. Fruit ripen with Delicious, around October 5 at Geneva.
They are described as being large (3g in.), oblate, with 80% bright red stripes over
yellow background. The fruit are medium fine, firm, tender and juicy, subacid, with
cream-colored flesh. Freedom will hold in normal refrigerated storage until January.

Freedom will be available (patent is pending) through licensed nurseries or from
the New York State Fruit Testing Cooperative, Geneva, N.Y. 14456. We plan to add
it to our disease-resistant test block at Belchertown.

**********

PERFORMANCE OF DISEASE-RESISTANT APPLES

William J. Manning and Daniel R. Cooley
Department of Plant Pathology

In 1978, we planted a block of disease-resistant apples at the Horticultural Research
Center at Belchertown. Fungicides have never been used in this block and only a
minimal insecticide program has been followed. Fruit were harvested for the first
time in 1982 and observations made and cultivar descriptions were published in FRUIT
NOTES (Vol. 48 No. 1, Winter, 1983, pp. 6-8).

Performance evaluations of the disease-resistant cultivars were continued in 1983.
Disease pressure was high in the spring due to long periods of cool wet weather and
near drought conditions and high temperatures were experienced during the summer.

During the second week in August, leaves were examined for symptoms of black
rot (frog-eye leaf spot) ( Physalospora obtusa ), cedar apple rust ( Gymnosporangium
juniperi-Virginianae), and scab (Venturia inaequalia). Twenty five leaves, on randomly-
selected terminals, were evaluated on each of 3 trees. Leaves were counted as having
significant symptoms if 2 or more spots of black rot, cedar apple rust or scab were
observed per leaf. Results were expressed as % of leaves with symptoms per 75 leaves
examined (Table 1).

-26-
Table 1. Evaluation of disease-resistant apples in Massachusetts, 1983.

Leaf symtpoms^

Cultivar

Black rot

Imperial Mcintosh

Liberty

Macfree

Nova Easy-gro

NY613452

Priscilla

Sir Prize

Cedar apple rust

Scab

48**

100***

% of 75 leaves on 3 trees with 2 or more spots/leaf-

5 or more spots/leaf.
**Both leaves and fruit.

All of the leaves and fruit of Imperial Mcintosh had significant scab lesions, while
all others were completely free from scab (Table 1). Sir Prize is very rust susceptible,
and respond accordingly. A few small, non-functional rust lesions were noted on
NY613452. Foliar black rot symptoms were more extensive than in 1982. An occasional
apple with black rot was observed for Macfree, NY613452, and Liberty (Table 1). This
may be a potential future concern if black rot innoculum continues to increase. For
comparison. Table 2 shows the disease-resistance ratings and commonly grown apple
cultivars from a test in New York State (Cornell University) published in 1983.

Table 2. List of disease resistance of some apple varieties from New York test, 1983.

Cultivar

Resistance rating

Apple scab Cedar apple rust fire blight Powdery mildew

Cortland

Delicious

Empire

Freedom

Golden Delicious

Idared

Jerseymac

Liberty

Macfree

Macoun

Mcintosh

Mutsu

Northern Spy

Nova Easygro

Paulared

Prima

Priscilla

Sir Prize

Spartan

3
1
2
2
4
3
1
1
3
2
1
3
3
1
2
4
1
3

3
2
2
3
3
4
3
2
2
3
3
4
2
2
3
2
2
4

4
2
3
2
3
3

3
3
4
3
3
3
2
3
2
2

1 = very resistant. No control needed.

2 = resistant. Control needed only under high disease pressure.

3 = susceptible. Control usually needed where disease is prevalent.

4 = very susceptible. Control always needed where disease is present.

Acknowledgements: We thank Tony Rossi and others at the Horticultural Research Center
for maintaining the block and applying insecticides. This activity is supported by
the Massachusetts Cooperative Extension Service.

-27-

GRAY MOLD ON STRAWBERRIES

Daniel R. Cooley and William J. Manning
Department of Plant Pathology

One of the most aggravating and economically damaging strawberry diseases is
gray mold. It strikes after primary investments in plants have been made, and presents
an ever-present, difficult to manage, disease problem. A conservative estimate gauges
yield lost from fruit rots in general at about 10%. In the Northeast, the majority
of this loss is caused by Botrytis cinerea, the gray mold fungus. Gray mold is a
particular problem because, unlike most other berry rots, it often attacks living plants
in the field as well as the harvested fruit.

The pathogen is well-adapted for survival. Botrytis occurs on a wide-range of
hosts, and while an isolate from a different host may not be as virulent as a strawberry
isolate, in most cases B. cinerea isolates can cause some degree of gray mold. Botrytis
also has the ability to colonize dead or living tissue. The fungus will often establish
itself on dead or aging plant tissue and move from that tissue to healthy areas. Petals
and other parts of older flowers are likely to be colonized first. These infections
may destroy the developing fruit immediately, or may remain latent until the fruit
is well-ripened or harvested. As the fruit ripens, it becomes easier for the fungus
to attack it, because endogenous enzymes in the fruit break down mechanical barriers
to fungal infection. Substrates for fungal growth become more available, and
biochemical defenses decrease as the fruit ripens, making a ripe strawberry an excellent
habitat for Botrytis and other rotting fungi.

Botrytis cinerea inoculum is very common. In strawberry plantings in the Northeast,
Botrytis usually overwinters in dead leaves and other decaying plant tissue, using
survival structures called sclerotia. In spring, as the temperature warms, the sclerotia
germinate and produce spores. These spores are carried about strawberry plantings
by air currents, splashing moisture or insects. In the presence of free water on the
plant, the spores germinate. Though the fungus is active over a wide range of
temperatures, optimum conditions for a Botrytis epidemic occur when temperatures
are approximately 60 to 70° F, and relative humidity exceeds 90%. If temperatures
and humidity are optimal, an epidemic can occur in as little as 28 hours. One of the
driving forces behind this rapid disease development is the prolific reproductive
capacity of the fungus. Gray mold is an example of what is called a 'compound interest
disease'. That is, each reproductive unit, in this case a condium or spore, can produce
hundreds of new spores, which can each produce hundreds more spores, and so on
as long as environmental conditions are favorable. Each generation progresses rapidly
in warm, humid weather. With conidia multiplying at a high 'interest' rate, disease
pressure becomes severe. Add to this the fact that initial inoculum is virtually always
present, and gray mold becomes extremely difficult to manage. Figure 1 shows a
diagram of the disease cycle for gray mold.

Most management efforts aimed at gray mold rely heavily on fungicides. To be
effective, fungicides must be applied at proper times. Most effective programs attempt
to prevent initial infections in the spring, and concentrate on protecting the plant,
particularly the flowers and fruit, from infections when environmental conditions
favor the disease. To be effective, a layer of fungicide must be kept on the plant

-28-
surface. A minimum spray schedule involves 3 applications, one at 10% bloom, one
at 50% bloom and one at tiie end of bloom. Where gray mold has historically been
a problem, applications should start at white bud, then the 3 bloom applications should
be made, and then applications should be made during fruit development at 5 to 10
day intervals. To maximize the protection it is wise to time spraying according to
plant development and weather. Rapid plant growth leaves tissue unprotected until
the next application, and heavy rain for more than 24 hours washes fungicides off
and provides an excellent infection environment. Therefore, in addition to the
prescribed applications, additional sprays should be made after 24 hours if rainy periods
occur.

Such intensive fungicide spraying can and has led to resistance to some chemicals.
Specifically, the systemmic fungicides, benomyl (Benlate®), thiophanate-methyl (Topsin
M®) and vinclozolin (Ronilan®) can become ineffective if used alone or too heavily.
The broad-spectrum contact fungicides, captan and thiram, are not likely to produce
the same problems. As a consequence Benlate®, Topsin-M® or Ronilan® should be
used in combination with a half-rate of captan. This reduces the risk of resistant
Botrytis developing, while enabling growers to use one of three very effective
chemicals. The rates for these chemicals are given in 'Managing Diseases and Insects
on Small Fruits in New England', available from the Massachusetts Extension Service,
Cottage A, University of Massachusetts, Amherst 01003.

There is another problem with the systemic fungicides in that they do not control
Rhizoctonia , Phytophthora , Rhizopus and Mucor , fungi which also cause berry rots.
In some cases, post-harvest rots caused by Rhizopus and Phytophthora have actually
increased where Benlate or Ronilan were the only fungicides used.

Cultural practices can reduce the amount of inoculum which contacts plants,
and reduce the free moisture on plants necessary for infection. Mulching with straw
or plastic keeps berries from contacting soil, hence reducing inoculum pressure and
improves fungicide coverage. Narrower rows promote air circulation and drying,
minimal weeds accomplishes similar goals. There is some evidence that adding
micronutrients may decrease gray mold, though the interaction of nutrition and the
disease has not received much study.

Some cultivars are more resistant to gray mold than others. In general, berries
which are firmer are more resistant. A recent study at Cornell rated the following
cultivars in decreasing order of susceptibility to berry rots: Honeoye, Guardian,
Canoga, Tenira, Surecrop, Holiday, Veestar, Vibrant and Earlidawn. Of these, the
first three cultivars were significantly more resistant than the others. Plant breeders
are continuing to develop gray mold resistant cultivars.

Finally, an experimental approach to control has been tried using the biological
control fungus Trichoderma . Preliminary results were not as consistent as control
achieved by fungicides, but Trichoderma may yet be developed into an effective
alternative to fungicide control. In the future, it may be possible to reduce or eliminate
fungicides by using a combination of resistant cultivars, biological control agents
and careful management of horticultural practices.

Obviously, these measures are aimed at reducing field incidence of gray mold.
These practices will, as a consequence, reduce post-harvest disease incidence.
Refrigeration is an option most small growers use to further reduce post-harvest
gray mold. Beyond one or two days after harvest, strawberries become increasingly
susceptible to rot, and the best strategy is to use or process them as soon as possible
after harvest.

Acknowledgment: Special thanks to Paula Saucier for the illustration.

-29-

spore
mass

In so'ing moisture encourages sderolia
to grow and produce spores

Fungus overwinters in plant debris, such
as dead leaves

When plants are wet. spores rapidly
intecl unprotected llorai parts

Infections cause browning and death in some
tlowers, or remain latent in developing Iruit

Alter harvest the potential lor rot increases greatly,
limiting storage to one to lour days

As llowers age and Iruit ripens, their susceptibility
to gray moid increases Older inlections are gray and
luzzy

GRAY MOLD ON STRAWBERRY,
BOTRYTIS CINEREA

Department of Plant and Soil Sciences Non-Profit Org.

French Hall U.S. POSTAGE

University of Massachusetts PAID

Annherst, MA 01003 Permit No. 2

3-20028 Amherst, MA 01002

FRUIT
NOTES

PREPARED BY
DEPARTMENT OF PLANT AND SOIL SCIENCES

COOPERATIVE EXTENSION SERVICE,
UNIVERSITY OF MASSACHUSETTS, UNITED
STATES DEPARTMENT OF AGRICULTURE AND
COUNTY EXTENSION SERVICES COOPERATING.

EDITORS
W. J. LORD AND W. J. BRAMLAGE

Volume 49 No. 3
SUMMER ISSUE, 1984

Table of Contents

Factors Influencing DPA Residues on Apples

Pomological Notes — Response to Chemical Thinning

Harvesting, Storing and Ripening Pears

Apple Fruit Growth

The "Marshall" Mcintosh

Pomological Paragraph

Pomological Notes

Predicting Harvest Size of Mcintosh Apples

A Survey of the Cost of Growing and Harvesting Apples
in Eastern New York in 1983.

Daily Activity of Apple Blotch Leafminer Adults

ssued by the Cooperative Extension Service, E. Bruce MacDougall, Dean, in further-
ince of the Acts of May 8 and June 30, 1914; United States Department of Agriculture
ind County Extension Services cooperating. The Cooperative Extension Service offers
squal opportunity in programs and employment.

FACTORS INFLUENCING DPA RESIDUES ON APPLES

William J. Bramlage
Department of Plant and Soil Sciences

Most apple growers in New England use diphenylamine (DPA) as a postharvest dip
or drench to control scald on apples. Although these treatments have been generally
effective in controlling scald, results of a given treatment are not always the same.
One reason for this is that fruit vary considerably in their susceptibility to scald,

depending on variety, fruit maturity, fruit nutrition, and growing conditions especially

the temperature that occurred during the days shortly before harvest.

Another reason for variable results is that a number of factors affect the amount
of residue left on fruit by a treatment. (It is this residue that protects the fruit from
scald during and following storage.) A recent study by Drs. Shih-Lo Lee, Asela Carag,
and Hesh Kaplan of Decco Tiltbelt Division, Pennwalt Corporation, Monrovia, California
(1) demonstrated some important factors influencing this residue.

Most of their studies were with Granny Smith apples, which are very sensitive to
scald, and most employed No Scald DPA EC-283®, 31% a.i., as the test material. Their
results can be summarized as follows:

1. Effect of DPA solution temperature. Cold apples were dipped in solutions at 41°,
55°, 70° and 95° F for 30 seconds, 1 minute, or 2 minutes. When dipped for 30
seconds, solution temperature had no effect on DPA residue, but when dipping
time was 1 minute a solution temperature of 95° F. doubled the residue left by
solutions at the lower temperatures. It should be noted that solutions of 41°, 55°,
and 70° F. all left approximately the same residue regardless of solution temperature
or treatment time.

2. Effect of fruit temperature. Cold apples were kept at 40°, 55°, or 72° F. for 10
to 12 hours to warm before dipping in a 70° F. solution for 1 minute. The coldest
apples (40° F) retained the least residue, but there was no difference between those
at 55° and 72° F.

3. Effect of dipping time. Apples were dipped for periods varying from 15 seconds
to 4 minutes. A dip of only 15 seconds produced less residue than the other dipping
periods, but all periods of 30 seconds or more produced the same residue.

4. Effect of DPA concentration. When apples were dipped in concentrations of DPA
varying from 500 to 2500 ppm, the amount of residue increased with concentration.
There was twice as much residue from 2500 ppm as from 500 ppm, but perhaps
of greater interest is the finding that there was about one-third more residue from
2000 ppm than from 1000 ppm, since our recommendation usually calls for use of
"1000 to 2000 ppm".

®
Trade name

-2-

5. Effect of additives. Addition of calcium chloride at 24 lbs. per 100 gallons did
not affect DPA residue, and neither did the addition of a surfactant.

6. Differences among varieties . The authors compared Granny Smith apples with
Golden Delicious, Delicious, Jonathan, and Rome Beauty. When the fruit were
all dipped under identical conditions, the residues were similar on all varieties
except Delicious, which retained almost twice as much residue as did the other
varieties.

7. Effect of DPA formulation. Three different commercial formulations of DPA
were tested under identical conditions, and one of the formulations left twice as
much residue as did the other 2 formulations.

Conclusions

These results indicate that apples should be treated for at least 30 seconds, but
that prolonged periods provide no additional benefit unless the dipping solution is hot.
They also show that cold apples will retain less residue than warm ones. However,
the temperature of the dip solution is of little consequence unless a quite warm solution
is used, which will greatly increase the amount of residue. They also illustrate that
the same treatment can protect different varieties to different extents, and that
different DPA formulations can produce different results. Within the solution itself,
DPA concentration was highly important, but addition of CaCl2 or surfactant had
no effect on DPA residue. Addition of fungicides to the solution was not tested.

The results of this study should be of considerable interest to apple growers, who
are frequently concerned about how treatment conditions affect scald control.

Literature Cited

1. Lee, S-L, A. Carag, and H.J. Kaplan. 1984. Factors influencing the uptake of
diphenylamine by apples. HortScience 19(l):94-95

POMOLOGICAL NOTES

William J. Lord
Department of Plant and Soil Sciences

Response to chemical thinning. The primary effect of chemical thinning is a reduction
in the number of smaller apples rather than a large increase in the size of the remaining
fruits. Thinning does not change a potentially small apple into a large fruit but helps
to insure that a potentially large apple will size properly.

-3-

HARVESTING, STORING AND RIPENING PEARS

William J. Bramlage
Department of Plant and Soil Sciences

Pears are not a major crop in New England, yet many growers have modest plantings
of them. Most of the crop is mari<eted locally by the grower, especially on roadside
stands. We are not presently conducting research on pears at the University of
Massachusetts, but we have periodically assessed the recommendations from other
areas to keep growers updated on developments. Here is our present view of the
requirements for marketing high quality pears.

Harvesting. Unlike most other fruits, pears cannot be tree-ripened or they will develop
core breakdown and will often become "gritty". They must be picked green, and most
importantly, they need to be picked at the correct stage of greenness. Unlike with
apples, for pears firmness is a reasonably good index of maturity. It can be measured
in the orchard with a penetrometer such as a Magness-Taylor pressure tester, but
because of the hardness of pears, it must be done with the 5/16 inch penetrometer
head, not the 7/16 inch head used on apples. The following firmness values have proven
to be resonably indicative of optimum maturity of pears in Massachusetts: Bartlett,
20-17 pounds; Bosc, 15-12 pounds; Anjou, 15-13 pounds; Comice, 13-11 pounds; Gorham
and Flemish, 14-12 pounds.

If pears are picked too immature, they tend to shrink in storage and to develop
poorer quality when ripe. However, the greater danger is from picking them at too
advanced a maturity, for this will greatly shorten their storage life and increase their
susceptibility to core breakdown, rotting, and CO2 injury. Perhaps the greatest problem
with pears is that growers do not pay close enough attention to picking them at the
correct time. It has been observed in England that a good key to pear maturity is
to note the ripening pattern of early apple varieties. If they are ripening unusually
early or unusually late, then pears are probably maturing in a similar pattern and their
expected harvest season should be altered accordingly. Maturity can then be monitored
more precisely with a pressure tester.

During packing, pears should be handled with care. Their hardness is misleading;
bruises incurred during harvest often do not show up until the pears ripen. Any two-inch
drop onto a hard surface will almost certainly produce a bruise.

S torage . If pears are to be stored, they should be cooled as quickly as possible. A
core temperature of 40° F. should be achieved in no more than 2-3 days, and the core
should be at storage temperature in no more than 10 days, or serious loss of storage
life will result.

Pears benefit greatly from storage as close to their freezing point as possible. Their
freezing point is between 27°F. and 29°F., and their recommended storage temperature
is 30-31° F. Obviously, that temperature requires great care in storage operation, but
the life of pears drops rapidly as storage temperature exceeds this recommendation.
For example, storage life of Bartletts is 3096 more at 30°F than at 32°F, and is 40%
more at 30°F than at 34°F.

-4-

Pears have clear limits on how long they can be stored and still retain their ability
to ripen properly after storage. In general, Bartletts seldom keep well in air beyond
December or early January; Bosc beyond February, and Anjou beyond March. If stored
longer than this in air, they will not ripen properly. Anjous present another requirement,
in that they will not ripen properly unless they have been kept at a low temperature
for close to 2 months.

Pears respond very well to CA for longer storage times. In some areas 1% O2 is
recommended. Pears can be very sensitive to CO2, so less than 1% CO2 in the storage
atmosphere is often recommended, especially in combination with 1% O2. CA studies
with pears in New York led to the recommendation of 2.5% O2 and less than 2.5%
CO2 for Bartlett and Bosc, so these conditions probably represent the best
recommendation for pears grown in the Northeast.

Pears are very susceptible to shrivel. Since it is difficult to maintain high enough
humidity in storage to avoid significant water loss and shrivel if pears are to be stored
for long, perforated polyethylene liners or bags are often used with success. At the
very least, it is desirable to place polyethylene sheets over the tops of bins before
storing pears. With a relatively high humidity to control shrivel, unacceptable amounts
of rots can develop on stored pears. Furthermore, pears (especially Anjou) may be
susceptible to scald. Protection against rot can be provided by a preharvest drenching
or dipping of the fruit with benomyl 50% WP at 8 ounces/100 gal. and if scald is a risk,
2700 ppm ethoxyquin can be added.

Ripening . For pears to achieve high quality, they must be properly ripened after storage.
They will ripen at 60-65°F, but if the humidity is low they can shrivel quickly during
this time. It is therefore necessary to either ripen them in a humid area or to cover
them with a polyethylene sheet during ripening.

If pears have been stored too long, they will not ripen properly regardless of
treatment. If it is intended to keep pears to the limit of their storage life, then you
should periodically remove samples from storage and test their ripening time. If it
takes less than 5 days for them to reach full ripeness, they are in danger of losing
their ability to ripen and should be stored no longer. Maturity at harvest and storage
temperature will markedly influence their maximum storage life.

Conclusion

Pears can be a very high quality commodity, but to produce this quality special
care is required. They must be harvested at the proper stage of maturity, handled
carefully, stored correctly and then ripened properly after storage if premium quality
is to be achieved. Many consumers are wary of pears due to unfavorable experiences
with them. When you are marketing your own pears locally, you have the opportunity
to educate your customers to the potential quality of pears, and to greatly increase
repeat sales.

-5-

APPLE FRUIT GROWTH
Franklin VV. Southwick^

There is often some confusion about the growth of apples, particularly concerning
the year-to-year variation in fruit shape and the growth during the harvest season.
During and shortly after bloom apparently is a critical stage in fruit development
because fruit size is primarily due to cell number, and cell division ceases about 3
weeks after full bloom. Thus, an apple with a greater number of cells at bloom, or
shortly thereafter, has the potential to become larger in size by harvest than one with
fewer cells.

Apple fruits increase in length and diameter after bloom. In 1914, J.R. Shaw in
Massachusetts reported on the relationship between shape of Ben Davis and Baldwin
apples and the temperature following bloom; the cooler the temperature, the more
elongated the apple. He concluded that during the post-bloom period, temperature
variations between the 6th and 16th day after full bloom fitted the observed variations
in shape more closely than did temperature variations during any other period. As
most growers know, distribution of seeds in fruit influences shape. Apples with a small
number of seeds are frequently lopsided, with the less fleshy side being the one lacking
seeds. The "king" fruit generally is larger than "side-bloom" fruit.

From approximately 3 weeks following bloom to harvest fruit growth is by cell
enlargement. Figure 1 shows typical growth curves for Early Mcintosh and Golden
Delicious apples plotted on the basis of fruit diameter and volume (assuming the fruit
to be a perfect sphere). It can be noted that the growth rate is constant with no "final
swell". In fact, when one plots the growth curve on the basis of diameter it appears
that the rate of apple fruit growth tends to slow down as the fruit approaches maturity.
This apparent slackening of growth rate is more pronounced for the later maturing
Golden Delicious than for the earlier maturing Early Mcintosh. If the data are calculated
on the basis of volume increase, however, it is apparent that the growth rate actually
accelerates in July and may not taper off appreciably for early apples and only slightly
before harvest for late varieties. Thus, there is no periods of accelerated or decelerated
growth as with the stone fruits. Fruit volume increases rapidly as fruit become larger
because progressively more volume is required to add a given increment to the fruit
diameter. This is shown in Table I where it can be seen, for example, that an increase
in diameter of 0.1 inch on a 2.60 inch apple represents a volume increase of 18.51 cubic
centimeters as compared to a 17.19 cubic centimeter increase in volume of a 1.50 inch
apple that has grown another 0.25 inch in diameter. Also, a 0.25 inch increase on a
3.00 inch apple represents an increase in volume almost equivalent to the entire cubic
contents of a 2.00 inch apple.

Since Mcintosh may grow at the rate of 0.07 to 0.10 inch in diameter per week
in September, the addition of 0.15 inch diameter on a 2.50 inch apple represents a 19.1
percent volume gain or a 17.2 percent increase in volume on a 2.75 apple within two
weeks. In other words, the delay in harvest of 2 weeks can add materially to the volume
of Mcintosh picked and to individual fruit size.

^Professor Emeritus, Department of Plant and Soil Sciences

-6-

Under optimum conditions the rate of fruit growth is so consistent that apple fruit
size at harvest can be predicted with reasonable accuracy as early as 35 days after
full bloom. However, a period of moisture stress can drastically reduce fruit growth.
The amount of growth lost from a soil moisture deficit or some other factor, causes
a non-recoverable loss in fruit size. Trickle irrigation is becoming a cost effective
practice to prevent loss in fruit size.

Table 1. The relationship of diameter increase to volume increase of apples (assumed to
be perfect spheres).

Apple

Increase in cubic

Diameter

Volume
ubic centimeters

centimeters per

Inches

Centimeters c

diameter increase

0.5

1.27

1.07

0.75

1.91

3.65

2.58

1.00

2.54

8.58

4.93

1.25

3.18

16.84

8.26

1.50

3.81

28.97

12.13

1.75

4.45

46.16

17.19

2.00

5.08

68.67

22.61

2.25

5.72

98.21

29.54

2.50

6.35

134.12

35.91

2.55

6.48

142.53

8.41

2.60

6.60

150.59

8.06

2.65

6.73

159.67

1:11) '-'

2.70

6.86

169.10

2.75

6.99

178.89

9.79

2.80

7.11

188.27

9.38

2.85

7.24

198.78

10.51

2.90

7.37

209.69

10.91

2.95

7.49

220.10

10.41

3.00

7.62

231.76

11.66

3.05

7.75

243.82

12.06 \

3.10

7.87

255.32

11.50/

3.15

8.00

268.19

12.87)

3.20

8.13

281.64

13.45 \ 63.43

3.25

8.26

295.19

13.55 /

When apples grow from
diameter % volume

(inches) increase

2.50

2.65

2.75

2. 90

19.1

17.2

-7-

^ 50

- 40

E
o

O £. Mc I ntosh- Diameter
D G. Delicious- Diameter
• f. Mc Intosh-Volume
■ (?. Delicious- Volume

- 160

- 140

- 120

00 3

c
o-

80 o'
O

60 %

13
June

II 21
July

I 12 25

August

29
September

Figure 1. Fruit growth rate for Early Mcintosh and Golden Delicious.

-8-

THE "MARSHALL" McINTOSH

William J. Lord and William J. Bramlage
Department of Plant and Soil Sciences

In recent years, tliousands of Marsiiall Mcintosh trees have been planted in New
England. The demand has exceeded the supply because until recently the only source
of this strain was a small nursery in Maine. We have described below the origin, growth
habit and fruit of the Marshall Mcintosh because of inquiries about the strain from
other Mclntosh-growing areas.

Marshall Mcintosh is a non-spur strain that originated on a branch mutation of
Mcintosh in the orchard of the Marshall Farm, Inc., 340 Marshall Road, Fitchburg,
Massachusetts 01420. The mutation was noticed in 1967 when the fruit developed red
color 2 or 3 weeks earlier than those on the rest of the tree.

The Marshall brothers have found that the Marshall strain can be harvested earlier
than other Mcintosh strains, and can also be pici<ed on the "normal" harvest dates without
adverse consequences. They report that the fruit stores well in both air and CA storage,
but believe more information is needed concerning the harvest and storage of the strain.

We at the University of Massachusetts as yet have little information about the
Marshall strain. However, we think it has real potential for CA storage because of
early coloring; that it will increase pack-out because of more red color; and that planting
of the strain will make the harvest season more orderly because the number of days
that Mcintosh can be harvested will be extended.

Our limited data show that at the Horticultural Research Center, Belchertown,
Massachusetts on September 6, 1978, 72% of the Marshall Mcintosh fruit were Extra
Fancy for color. On this date only 40% of the Cornell strain of Mcintosh was Extra
Fancy. On August 30, 1979, 75% of the Marshall were Extra Fancy in comparison to
43% of the Cornell fruit. Lastly, on September 4, 1980, 53% of the Marshall Mcintosh
were Extra Fancy and only 16% of the Cornell Mcintosh fruit were of this grade for
color. We also believe that the red color is more intense on Marshall than on other
strains of Mcintosh. Our data suggested that the maturations of Cornell and Marshall
strains were similar as indicated by flesh firmness and sugar content of the fruit. Thus,
limited observations suggested that Marshall Mcintosh is an early coloring strain, not
both an early coloring and early maturing strain.

In 1979 we established a planting in which Marshall Mcintosh is being compared
with 6 other strains of the variety. Hopefully, we shall be able to obtain more reliable
and complete information on the maturation of these strains and on their keepability
in air and CA storage.

-9-

In 1983, the trees for the first time bore sufficient fruit for some evaluations. On
three dates. ..September 1, 7, and 14. ..fruit on trees of all seven Mcintosh strains were
visually evaluated for red color. It should be recealled that August and early September
were very hot in 1983, and that red coloration was very slow. On both September 1
and 7, two-thirds of the Marshall Mcintosh had at least 5096 of their surface colored
red. This was far superior to the coloring on any of the other strains. By
mid-September, 84% of the Marshall were well colored, and only one other strain had
close to that amount of color. Thus, even under growing conditions unfavorable to
red color development, Marshall Mcintosh developed color earlier than other strains.

On September 7 and 14, samples of fruit were picked from these trees and measured
for firmness and for starch disappearance. At the first picking Marshall Mcintosh
were neither firmer nor softer than those of any other strain. At the second picking
they were firmer than Macspur, Eastman, and Gatzke Mcintosh, none of which was
as red as Marshall. At neither picking did Marshall have either more or less starch
than any other strain.

These results must be evaluated with great care as they represent fruit from young
trees, with the fruit varying in size but tending to be unusually large. It will not be
until the trees are bearing consistent and representative crops that reliable conclusions
can be drawn, but the indications in 1983 were consistent with earlier observations:
Marshall Mcintosh appear to color early, but not to mature early.

Table 1. Influence of Mcintosh strain on red color of fruit and fruit maturity, 1983.

Strain

Percentage of fruit with
sufficient color for
Extra Fancy grade^

""971 Wt 97TT

Fruit

Firmness
(lbs)

9/9

9/17

Maturity
(l-9)y

9/9

9/17

Morspur

Marshall

Imperial

Macspur

Eastman

Gatzke

Rogers

17b

20b

57bc

64a

67a

84a

15b

23bc

68ab

8bc

33b

56bc

25d

9bc

17c

53bc

8 be

28b

39cd

1 5 . Sab

15.3ab

14.7b

14.8b

15.3ab

16.0a

14. Sab
14.9a
14.4abc
13. Bed
13. 6d

1.40bcd
14.5abc

1.9ab

1.7ab

1.9a

1.36b

1.8ab

1.5ab

2.5a
2.8a
2.7a
2.6a
2.8a
2.3a
2.3a

^At least 50% of fruit surface with red color typical of the variety,
y Based on Starch-Iodine test: 1-im mature; 9-overmature

-10-

POMOLOGICAL PARAGRAPH

William J. Bramlage
Department of Plant and Soil Sciences

Measuring temperatures in cold storages. We have frequently urged storage operators
to stop relying on a single thermometer placed near the door to measure storage
temperatures. Totally unnecessary risks result from this method of monitoring storage
temperature. A better method is to use remote sensing devices, such as thermocouples
or thermistors, located at key positions within the storage.

A recent publication, prepared by J. A. Bartsch and G.D, Blanpied of Cornell
University, gives step-by-step instructions for installing and using a thermocouple
system for measuring storage temperatures. We urge any storage operator who is
not presently using remote temperature measurement to obtain this publication and
to use it as a guide for installing such a system. A small error in temperature control
can cause a very large loss in fruit quality. A storage operator needs to have as precise
a measure of storage temperatures as he can get. The publication, "Temperature
Monitoring System for Cold Storage" is Extension Bulletin 430, and can be obtained
by writing Helen Rogers, Department of Agricultural Engineering, Cornell University,
Ithaca, New York 14853.

:j(:^:^;t:^>t:4:4::f::t=

POMOLOGICAL NOTES

William J. Lord
Department of Plant and Soil Sciences

Plastic bags filled with dirt aid in tree training. According to the Great Lakes Fruit
Growers News (April, 1983) Paul Friday of Coloma, Michigan is using small plastic
bags with 2 to H lbs. of dirt as tree training aids for young peach, apricot, and tart
cherry trees. The dirt-filled plastic bags are fastened with 2 clothespins to the ends
of branches requiring spreading. Mr. Friday believes that wide crotch angles on peach
trees, as a result of limb positioning, has reduced the number of canker-infested
crotches.

Producing your own fruit trees. Until recently fruit growers experienced difficulty
in obtaining trees from nurseries. Because of this problem, many growers began to
propagate their own trees. However, it is now evident that most of us are producing
low quality trees which in the long-run will cost us more because of poor performance
in the orchard than those purchased from a commercial nursery. Reasons for our lack
of success in propagation include poor soil for a nursery, lateness of lining-out the
rootstocks, and/or neglect of the nursery.

-11-

PREDICTING HARVEST SIZE OF McINTOSH APPLES
F.W. Southwickl

It is known that apple fruit size at harvest from healthy trees can be predicted with
reasonable accuracy by measuring fruit size much earlier in the growing season.
Therefore, measurements of fruit diameters in July or later can be used to accurately
estimate average fruit size of Mcintosh in early- mid- or late-September, assuming
severe drought conditions do not develop during July or August. By taking some early
size measurements a grower can determine whether or not he should consider doing
some hand thinning to improve the overall size of the persisting fruit at harvest. The
earlier hand thinning is done after completion of the June drop, the greater the
improvement in size of the persisting fruit and the smaller the decrease in total yield.

Data in Table 1 can serve as a guide, showing the approximate harvest size of Mcintosh
on September 15 when fruit diameters were measured on July 15 and August 1. It is
assumed that the Mcintosh were sprayed with Alar-85 in mid-July at a concentration
of 1000 ppm for pre-harvest drop control. To determine average fruit size, measure
at least 25 fruits a random on several trees in each block. A suitable measuring device
for measuring fruit diameters (Cranston Calpher) can be purchased from the McCormack
Fruit Tree Co., Inc., 611-A Englewood, Yakima, Washington 98908.

Table 1. Prediction of fruit diameter (inches) of Mcintosh apples on September 15,
based on size on July 15 or August 1.

Fruit diameter

Predicted fruit

July

diameter on
September 15

1.4

2.45

1.5

2.55

1.6

2.65

1.7

2.75

1.8

2.85

1.9

3.00

2.0

3.10

Fruit diameter

Predicted fruit

August 1

diameter on

September 15

1.8

2.25

1.9

2.35

2.0

2.55

2.1

2.65

2.2

2.78

2.3

2.95

2.4

3.05

2.5

3.15

Professor Emeritus, Department of Plant and Soil Sciences

-12-

A SURVEY OF THE COST OF GROWING AND HARVESTING
APPLES IN EASTERN NEW YORK IN 1983

William D. Gerling^

Regional Extension Specialist

Hudson Valley Lab, Highland, New York

This is a survey and analysis of the cost of growing and harvesting apples for eight
operations in Eastern New York, It includes operations from throughout the Hudson
and Champlain Valley apple producing region. The objective of this study is to assist
growers in identifying and analyzing that portion of their total expenditures which
can be associated with the growing and harvesting portion of their business. The data
contained within the study is thought to be representative of what better-than average
growers are doing.

Method of Obtaining Data

Throughout the 1983 growing season, the growers in the survey were asked to keep
a record of where labor was used. In early 1984 the eight operations were mailed survey
forms to collect the labor information and other needed information. A short time
later, each operation was visited to pick up the forms and collect any additional
information that was required.

The operations included ranged in size from 41 acres of apples to 585 acres. The
fruit produced by these growers account for approximately 8% of the apples produced
in Eastern New York.

The sample of operations that is included in this study is neither a stratified nor
random sample. The purpose of this study is to provide growers with a management
tool with which to analyze their business. While the data contained in this report is
useful in evaluating a growers operation from a management standpoint, it may not
be representative of average costs in Eastern New York for other purposes.

Orchards Included in the Survey

For this study, acreage of bearing trees include all mature trees, even though they
may not have produced a crop or the crop may have have been harvested. It also includes
all young trees that produced enough fruit to make harvesting economically feasible,
even though the volume of apples might not have been sufficient to cover the cost
of growing the fruit. Using this method of determining a bearing acre can have a major
impact on a growers average yield, since the number of bushels of apples harvested
are divided by the total number of acres considered to be bearing. If a grower has

^Reprinted with the permission of the author.

-13-

a large acreage of young trees just coming into production, his average yield may be
considerably less than a grower who is dealing only with mature trees. This may also
increase both his growing and harvesting cost per bushel in the short run. However ,
if a grower is going to maintain a productive orchard over the long run, it is desirable
and even necessary that he constantly plant young trees. If a new planting is expected
to have a useful life of from 20-25 years, then approximately 4-5% of the total acreage
should be replanted each year. Replanting about the same number of acres each year
is desirable from several standpoints:

1. It insures that the productive base of the farm is constantly being renewed.

2. It makes it much easier to provide the labor and equipment needed for the operation
as compared to planting larger acreages on an irregular basis.

3. The cash flow needs of business are more constant. It costs from $6,000-$10,000
per acre to plant and care for a young orchard until it begins to pay its own way.
When replanting is done on a regular basis this cash flow drain is also more constant
and more easily planned for.

This year, data was again collected to show the age breakdown of the trees on
each operation. This is summarized in Table 1. It illustrates the importance that these
growers have placed on establishing new orchards in recent years. However, it also
illustrates that orchard replanting has been a very sporadic activity on several of the
operations in the study, rather than a regular activity. Many of these operators have
now recognized the need to plant approximately the same number of acres of young
orchards each year.

This year we collected information on the number of acres pruned, average number
of sprays per acre, number of acres receiving herbicides, average number of times
each grower mowed his orchard and information on irrigation practices. This data
is summarized in Table 1 also. Hopefully, it will provide growers with a better
understanding of how their cost might compare to the figures contained within this
publication.

Summer pruning includes all pruning activities done in the bearing orchards during
the time from petal fall to harvest, including suckering. The number of sprays per
acre include the average of all the sprays to an orchard for insect and disease control,
growth regulations, thinning, and foliar fertilizers. The number of bearing acres
receiving herbicides include those acres that received some type of herbicide treatment.
Some of these may have been treated more than once.

All the costs associated with the production of the apple crop on acres of apples
considered to be bearing acres are included in Table 2. In some cases, it was easy
to identify those expenses associated with the growing phase of the operation, for
others it was necessary to estimate what percent of the total expenditure was associated
with growing the crop. An example of the latter is the management salary. On none
of these operations was one person in charge of only growing the apples. Therefore,
it was necessary to estimate what portion of the manager's salary should be charged
to the growing phase of the operation. Also, it was necessary to separate the costs
of caring for the young non-bearing acres and the costs associated with the bearing
acres.

-14-

The return on investment for orchards, building and equipment recognizes the cost
of having capital tied up in the business. If a grower is relying on borrowed capital
to finance the ownership of the orchards, buildings and equipment, this cost of capital
is an easily identified cost. It is the interest he must pay his lender. However, this
cost exists, even if a grower is using his own money. The dollars invested in the business
have an earnings potential of their own. These dollars could be invested in the bank
or elsewhere and produce some income. This earnings potential must be recognized
as an opportunity cost of capital, when a grower invests his money in his own business.
His business must earn a profit, over and above the basic earning potential of his capital,
to be profitable in a real sense. In this publication the return on investment or
opportunity cost of capital is calculated at the rate of 1296 of the value of orchard,
buildings and equipment.

The value of the orchards, buildings and equipment was obtained by asking each
grower to estimate the market value of bearing orchards, buildings used in the growing
phase of the business and equipment used to grow the apple crop. The return on
investment for the orchards and buildings is included in the orchard overhead group.
The return on investment for the equipment is included under equipment on Table
2.

The real estate tax represents the taxes actually paid on the bearing orchards and
the taxes on the buildings used to store growing equipment and materials. In most
cases it was necessary to break these out from a total tax bill.

Rentals includes the payment made for orchards or buildings not owned by the
grower. Five of the participating growers rent some orchards and/or buildings.

The category "other" under orchard overhead in Table 2 includes insurance, short
term interest, and any miscellaneous cost associated with the growing phase of the
business. The short term interest includes only the interest on loans made to produce
the crop, typically they might include loans for pruning, materials, etc. It does not
include interest on loans for the purchase of equipment, buildings, orchards, etc. This
type of interest would be covered under the return on investment.

The labor costs in Table 2 includes the gross wages paid the employee plus the
employer's share of social security, workmen's compensation, unemployment insurance
and the cash cost of any fringe benefits.

Harvesting Cost

Table 3 illustrates the costs associated with the harvest operation. Many of these
costs, unlike those in the growing costs, vary directly with the amount of fruit harvested.
Therefore, they are shown on a per bushel basis, rather than a per acre basis.

The picking and other labor categories includes the gross wages paid for harvesting
apples plus any bonus and/or incentives. They also include the employer's share of
social security, workmen's compensation, unemployment insurance and any other benefits
paid other than housing and transportation. The harvesting costs include the cost of
harvesting all fruit, including drops.

-15-

Summary

The average 1983 growing cost was $1,231.61 per bearing acre. This was up 12%
from $1,100.97 in 1982. Most of this increase can be attributed to the weather
experienced throughout the 1983 growing season. The major increase occurred in the
labor and materials categories. The mild winter we experienced allowed growers to
prune more trees which increased the amount of labor cost associated with pruning
and brush removal. The cold, wet spring made it necessary for a number of growers
to apply more fungicides. The very hot and dry period of July, August, and early
September caused a number of growers to increase their use of insecticides and
miticides. This same weather pattern also meant that many growers had to irrigate
more than in past years.

The average per bushel growing cost was $2.67 in 1983 as compared to $2.10 in 1982.
This increase of 27% was due in part to the increase in the per acre costs but more
importantly to a decrease of 64 bushels in the average yield per acre. This yield
decrease can also be attributed at least in part to the weather.

The harvesting cost for 1983 was $1.50, approximately the same as the $1.48 in 1982.
The combined growing and harvesting cost for 1983 was $4.17 as compared to $3.58
in 1982 and $4.25 in 1981. The major reason for the changes in the per bushel costs
over the past three years has been the fluctuation in the average yield.

Fruit Quality

It should be remembered that these figures are an attempt to measure the cost
of growing and harvesting apples. One major factor, which impacts the profitability
of an operation, which has not been discussed, is fruit quality. This is a factor which
growers cannot afford to overlook when they are evaluating their yields and costs.
It is very possible for a grower with higher production per acre and lower costs to
be less profitable than his neighbor. This is because the increase in production and
reduction in costs may come at the expense of quality.

In using the figures contained in this article to analyze his business, a grower must
keep the concern for fruit quality foremost in mind. A growers ability to produce
high quality fruit at a reasonable cost will determine his success.

Table 1. Eight operations, 1983

-16-

Total acres of apples
Acres of bearing apples
Percent of non-bearing

Total
1,936
1,558

Average
242
195
20

Range

41-585

21-473

7-49

Tree age (% of total acreage)

1-5 years

6-10 years
11-15 years
16-20 years
21-30 years

over 30 years

24
23
9
14
11
19

6-59
2-38
2-20
0-25
1-20
0-39

Apples harvested (bu.)
Picked fruit
Drops

717,615

640,598

77,017

,702
,075
,627

10
10,

,385-162,115
151-154,175
234-28,561

Total estimated crop

724,615

,577

,885-162,115

Percent of crop harvested

95-100

Yield per acre (bu. harvested)

461

343-685

Percentage of crop harvested as drops

2-23

Number of bearing acres pruned
Dormant
Summer

1,268
783

159
98

NA
NA

Percentage of bearing acres pruned
Dormant
Summer

81
50

31-100
0-100

Average number of sprays per acre

13.5

10-17

Number of bearing acres receiving herbicides

161

20-473

Average number of times mowed

3.8

3-5

Number of acres irrigated

347

0-180

Average number of times acres irrigated

1.23

-17-

Table 2. Growing cost (dollars per bearing acre) eight operations, 1983

Orchard overhead
Real estate tax
Return on investment
Rental
Other

Management
Salary

Accounting/secretarial
Office expense

Labor

Pruning & brush removal

Spraying

Orchard floor management

Irrigation

Other

Equipment
Depreciation
Return on investment
Fuel

Repairs & maintenance
Other

Materials
Fungicides
Insecticides
Miticides
Spray oil

Growth regulators
Herbicides
Lime and fertilizer
Other

Total

Total growing cost per bearing acre
Yield per acre (bu.)
Cost per bushel

Average

$23.37

214.82

18.31

50.59

$307.09

$113.87

$273.66

Range

$15.08 - 28.30

83.52 - 545.14

0.00 - 98.34

8.00 - 113.81

$206.85 - 662.67

$86.41

$34.15 -

187.07

22.73

5.13 -

87.17

4.73

2.37 -

11.76

$55.99 - 276.61

$147.10

$77.02-

233.00

38.14

12.55 -

56.48

30.07

15.30 -

55.07

8.29

0.00 -

49.71

50.06

9.44 -

146.15

$166.31 - 366.00

$50.33

$31.34

- 112.10

60.40

37.61

- 134.52

47.79

16.28

- 68.81

75.32

34.21

- 105.71

7.60

0.00

- 13.00

$241.44

$157.08

- 409.81

$75.93

$49.99

- 115.38

54.32

30.25

- 90.32

53.13

36.49

- 77.38

6.71

0.00

- 17.61

29.53

17.10

- 44.80

8.88

2.18

- 16.89

28.57

7.56

- 49.21

38.48

13.42

- 68.86

$295.55

$209.67

- 441.32

$1,231.61

$977.43

-1,836.38

461

343

- 685

$2.67

$1.72

- 3.96

-18-

Table 3. Harvesting costs (dollars per bushel) , eight operations, 1983.

Equipment
Depreciation
Return on investment
Fuel

Repairs and maintenance
Other

Total

Containers
Depreciation
Return on investment
Repair and maintenance

Total

Housing for pickers
Depreciation
Return on investment
Repairs and maintenance
Insurance

Fuel and electrical
Real estate tax
Supplies

Total

Picking Labor

Picker transportation

Other labor
Supervision
Fruit handling
Accounting/secretarial

Total

Other harvesting costs

Total harvesting cost per bushel

Average

.03
.04
.03
.04
.02

.16"

.09
.10
.03

~J2

.02

.06

.03
*

.02
.01
.01

lis"

.59
.09

.13
.11
.02

'J26

.03

1.50

Range

.02 -

.06

.03 -

.08

.01 -

.05

.10

.06

.07 -

.33

.05 -

.12

.06 -

.14

* _

.11

.13 -

.30

.05

.01 -

.12

.10

.01 -

.05

.00 -

.01

* _

.01

.07 -

.30

.48 -

.87

.03 -

.13

.05 -

.23

.07 -

.17

* _

.05

.14 -

.40

.00 -

.08

1.12 -

1.98

Less than .01 per bushel

-19-

DAILY ACTIVITY OF APPLE BLOTCH LEAFMINER ADULTS^

T.A. Green and R.J. Prokopy
Department of Entomology

Over the past 8 years, the Apple Blotch Leafminer (ABLM), Phyllonorycter
crataegella, has become a serious pest in commercial apple orchards east of the Hudson
River, High populations of this organophosphate resistant insect have been associated
with reduced fruit size, premature fruit ripening, and reduced fruit set the following
year in some cultivars.

In a previous issue of FRUIT NOTES (Spring, 1983) we reported on the development
of a visual monitoring trap for ABLM adults. Concurrent with that work, we conducted
a study of the behavior of ABLM moths in and around commercial apple orchards. Our
study has thus far been restricted to the second and third adult flights, occurring in
early July and late August, respectively.

To determine the location and activity of ABLM adults, we performed 1 minute
observations of various tree structures including the upper leaf surface, lower leaf
surface, fruit, trunk, and ground cover, at 1 hour intervals. We recorded the numbers
of ABLM observed at each location. In like fashion, we observed the tree canopy for
flight activity.

Our results are presented in Figure 1. We found the primary location of stationary
ABLM throughout the day to be the lower leaf surface. We observed a number of mating
pairs, again predominantly on the lower leaf surface, and exclusively before 11:00 AM.
We also observed several ovipositing females, all on the lower leaf surface, and all in
the late afternoon and evening.

We found flight activity to be concentrated during two periods of the day, from
sunrise to 3-4 hours after sunrise, and from 3-4 hours before sunset to sunset. The number
of flights observed per minute during the AM flight period was approximately 2.5 times
that of the PM flight period. During the AM flight, landings on the upper leaf surface
outnumbered lower leaf surface landings by a 2 to 1 margin. This ratio was reversed
in the evening.

To further investigate the differences observed between the two flight periods,
we captured flying ABLM and determined their sex. We employed three capture methods:

^ We wish to express our appreciation to research assistants Geoffrey Hubell and Martin
Rose, and to the following families for use of their orchards: Jack DeLuca, Ed Roberts,
Dave Shearer, Harvey and Marvin Peck, Ray Davis, and Cameron Sewell (in New
Hampshire).

-20-

visual traps; net sweeps; and captures of moths by an aspirator immediately after landing.
These results are presented in Figure 2. All three methods indicated that the AM flights
were virtually all made by males, whereas the PM flights were made predominantly
by female moths.

We found the same general pattern of activity to occur on non-host trees adjacent
to orchards, but far fewer ABLM and no ovipositions were observed there.

In summary, then, our study indicates that at least during the second and third
generations, male ABLM moths fly from first light to approximately 9-10 AM, probably
searching for females to mate. Virtually all mating occurs during this time. This strategy
may be designed to minimize wind disruption of sex pheromone trails emitted by females,
by taking advantage of the lower wind speeds usually associated with this time of day.

From mid-morning to approximately 5 PM, ABLM adults are largely inactive and
are located in relatively concealed and shaded areas, possibly to avoid desiccation and
predation. In the evening, females are in flight, probably foraging for ovipostion sites.

On the basis of our results, we recommend that insecticide applications for adult
ABLM be timed to coincide with the evening flight period. This will maximize both
the effectiveness of any fumigant action and contact of females with fresh insecticide.
This season we plan to investigate the effect of temperature on oviposition rates, and
to extend our observations to the overwintering generation of adults.

-L

-21-

22.87

Number .
ABLM '
Dbserved

Sunrise
10 AM

I 1

I i

9.24

Number ,
ABLM '
Observed

10 AM to
5 PM 1

JZZL

8.24

lea

8.81

Number

ABLM 3
Observed

5 PM to
Sunset .

Lower

Leaf

Surface

Upper

Leaf
Surface

Fruit

Trunk

Ground
Cover

Flight

Figure 1. Number of ABLM adults observed per minute at various

locations during three different time periods.

-22-

-L

5.13

Number 2
of ABLM
Captures

Sunrise to
10 AM 1

cTU

K33L

Number
of ABLM
Captures

5 PM to
Sunset

:si

I — ^

_ r> . Sweep Net .

Trap Captures Captures Aspirations

Per Hour Per Minute Per Minute

Figure 2. Number of ABLM adults captured by three different

methods during morning and evening flight periods.

a UJ O

•; (J) CVJ .-

°< oS

- t- O 2 <

° O < t: f.

11. a. CL E t;

E
<

O M

CO ji

CO t') 5i

Q. ro «—

O ^ <

S- s; E E S

Q LL D < PO

FRUIT pr
NOTES

PREPARED BY
DEPARTMENT OF PLANT AND SOIL SCIENCES

COOPERATIVE EXTENSION SERVICE,
UNIVERSITY OF MASSACHUSETTS, UNITED
STATES DEPARTMENT OF AGRICULTURE AND
COUNTY EXTENSION SERVICES COOPERATING.

EDITORS
W. J. LORD AND W. J. BRAMLAGE

Volume 49 No. 4
FALL ISSUE, 1984

Table of Contents

Fruit Notes Subscription

Bigger Apples, Less Calcium, More Problems

Photographs of Nutrient Deficiencies and Toxicities
and Heat Stress

Pomological Paragraph —

New Apple Rootstock Available

The Consumer's View of Fresh Pears

Pomological Paragraph — Harvest Indices

Do Fungicide Residues Affect
Apple Maggot Fly Egglaying?

Effects of Rootstock and Stempiece/Rootstock
Combinations on Growth, Leaf Mineral Concentrations,
Yield and Fruit Quality of "Empire" Apple Trees

Issued by the Cooperative Extension Service, E. Bruce MacDougall, Dean, in further-
ance of the Acts of May 8 and June 30, 1914; United States Department of Agriculture
and County Extension Services cooperating. The Cooperative Extension Service offers
equal opportunity in programs and employment.

FRUIT NOTES SUBSCRIPTION

The Fall Issue of FRUIT NOTES is the 4th and last issue for the year. Now is
the time to renew your subscription for 1985. The question has been asked about
multi-year subscriptions. This would be desirable but the Editor of FRUIT NOTES
retires in 1985 and the fate of this publication after this date is unknown.

To subscribe to FRUIT NOTES complete and mail the following form with your
check for $3.00. (Canadian subscribers please send a U.S. postal money order.)

William J. Lord

Editor, FRUIT NOTES

Name

Mailing address_

Town, State, Country Zip

Make checks payable to: FRUIT NOTES ACTIVITY ACCOUNT.

Send subscription form and check to: William J. Lord

Department of Plant and Soil Sciences
French Hall

University of Massachusetts
Amherst, MA 01003

-2-

BIGGER APPLES, LESS CALCIUM, MORE PROBLEMS

William J. Bramlage
Department of Plant and Soil Sciences

It has frequently been observed that large apples do not store as well as small
apples within a given variety. When storage problems occur, they tend to be much
more prevalent on the largest apples within a box.

This relationship of storage disorders with fruit size is largely a reflection
of the fact that within a sample of fruit, calcium (Ca) concentrations are lower
within the larger fruit. For example, Dr. Mack Drake recently analyzed some
random samples of different sizes of packed Mcintosh apples. The results (Table
1) showed a marked reduction of fruit Ca as size increased. We have seen many
times that differences in Ca concentration of this magnitude can lead to quite
different amounts of breakdown, rot, bitter pit, and even scald on Mcintosh after
storage.

Table 1. Calcium concentration in Mcintosh apples of different sizes, 1983.

Box Fruit Average Ca concentration^

count circumference fruit weight (ppm dry wt.)

(g)

Fruit

circumference

(inches)

.5 -

.7 -

.9 -

.1 -

160 2.5 - 2.6 100 129

140 2.7 - 2.8 122 119

120 2.9 - 3.0 154 HI

96 3.1 - 3.2 186 90

^Ca concentration in outer cortex tissue on calyx half of the fruit.

The relationship between fruit size and fruit Ca concentration in apples has
been studied extensively by Michael A. Perring at the East Mailing Research Station,
Kent, England. In bulk samples, he has found that the relationship is very dramatic
(Figure 1). The main reason for larger fruit having lower Ca concentrations is
that the amount of Ca transported by the tree into developing apples is very small,
and as apples enlarge their cells get larger and the concentration of Ca in them
becomes diluted by water and other cellular constituents. Large apples have larger
cells, hence their Ca is more diluted.

Another reason for the fruit size: Ca relationship is that relatively large fruit
generally come from low-yielding trees, or areas of trees. With light cropping
more vegetation is produced, and what Ca is available in the tree is preferentially

-3-

transported to the vegetation; in general, the more vegetation there is per apple,
the less Ca is available for the fruit.

The pattern shown in Figure 1 can be expected when examining bulk samples
of apples. However, when you measure individual apples the pattern is not as
distinct (Perring and Jackson). A large apple does not always have a low Ca
concentration, and a small apple does not always have a high Ca concentration.

I 20

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50 100 150

MEAN WEIGHT PER APPLE (g)

200

-4-

even when the fruit all come from the same tree on the same date. Obviously,
there are factors that affect the movement of Ca into individual apples, since
apples of a given size and variety can vary considerably in the total amount of
Ca they contain (Perring and Jackson).

Perhaps the most dramatic variation from this pattern is found with very small
apples. Perring has observed that very small apples (which should have high Ca)
sometimes are heavily afflicted with bitter pit. We have also observed that very
small Mcintosh and Delicious are sometimes severely broken down. We have also
noted that these small apples with breakdown often contain no, or almost no,
plump seeds, and in a recent study we found that in Delicious, fruit Ca concentration
decreased as seed number decreased, even when the fruit were all the same size.
We have also noted that Mcintosh with few or no seeds tend to mature earlier
than ones with many seeds, as as is well known, more mature fruit tend to
deteriorate faster than less mature fruit. Thus, seed number may be one cause
of the variation in Ca concentration among fruit of a given size. Poor pollination
may contribute to low fruit Ca.

The absolute relationship between apple size and Ca concentration changes
somewhat from year to year (Perring and Jackson) and also varies considerably
from variety to variety (Perring), even when bulk samples are analyzed. For
example, Perring found that for a given size of fruit, Mutsu contained a higher
Ca concentration than did Cox, although in both varieties the general pattern
of Figure 1 was displayed.

These findings demonstrate that while there is not an absolute fruit size: fruit
Ca relationship, there certainly is a strong and highly important general relationship.
When growing conditions are such that average fruit size is increased for a variety,
average fruit Ca can be expected to be lowered, and with this lowering of fruit
Ca concentration there is increased potential for fruit disorders during and after
storage.

This situation creates a paradox for apple growers. Production of larger fruit
can increase yield substantially, thereby increasing potential income substantially.
However, this greater fruit size creates a greater Ca problem, and needs to be
accompanied by remedial actions to prevent reduced storage life of the fruit that
have been produced. Production of larger fruit increases then need for foliar
applications of Ca and/or for postharvest Ca treatments to the fruit.

It is the opinion of many investigators that the "calcium problem" of apples
that exists world-wide today is one that has been created by intensive production
methods that have increased average fruit size and yield. It is unlikely that the
need for high productivity will diminish with time, and so it is also unlikely that
the need for Ca treatments will diminish with time.

Literature Cited

1. Perring, M.A. 1979. The effects of environment and cultural practices on cal-

cium concentration in the apple fruit. Commun. Soil Science and Plant
Anal. 10:279-29 3.

2. Perring, M.A. and C.H. Jackson. 19 75. The mineral composition of apples.

Calcium concentration and bitter pit in relation to mean mass per apple.
J. Sci. Food Agric. 26:149 3-1502.

-5-

PHOTOGRAPHS OF NUTRIENT DEFICIENCIES AND TOXICITIES AND HEAT STRESS

William J. Lord
Department of Plant and Soil Sciences

In the past, we occasionally published in FRUIT NOTES photographs of nutrient
deficiencies. Last year when we had numerous problems - severe scab outbreak in
some orchards, hail, russetted apples, small fruit, an extremely wet spring, a dry
summer, slow color development on fruit of some varieties, etc. - it became apparent
that confusion existed concerning nutrient deficiency symptoms. Deficiency symptoms
recognition that caused problems were mainly boron (B), potassium (K) and magnesium
(Mg). Therefore, for your information we have again published photographs and brief
descriptions of some nutrient deficiencies of apples and pears.

Calcium (Ca). Bitter pit and cork spot are visual evidence of low Ca in apples and
are more prevalent on some varieties and years than others. Bitter pit is common
on Cortland, Baldwin and Northern Spy whereas cork spot is much less prevalent but
can be found on Delicious and Golden Delicious in New England.

The Delicious on the left in Figure 1 shows bitter pit and the one on the right

Figure 1. Symptoms of calcium deficiency on Delicious fruit.

-6-

has cork spot. Bitter pit is most frequently associated with the calyx end of the apple
and its severity may increase in storage. Cork spot is not localized and will appear
anywhere on the apple. The spots are more pronounced than bitter pit, being much
deeper and wider. In some cases the cork spot resembles the inner cone of a miniature
volcano, with the depressed skin area containing green or dark red pigment. Cork
spot does not increase in severity in storage.

Magnesium (Mg) Deficiency. Mg deficiency of apple and pear trees has been more
prevalent in orchards the last 2 years probably due to excessive rainfall early in the
growing season. These visual observations were supported by leaf analysis which
indicates that Mg is exceptionally low in some instances.

Mg symptoms are characterized necrotic (brown) areas between the veins (Figures
2, 3). The older basal leaves on shoots and spurs are usually affected first and as the

Figure 2. Magnesium deficiency symptoms on apple leaves.

-7-

season progresses the injury symptoms appear on the younger leaves. The deficiency
symptoms frequently become apparent in late July and early August. By late summer,
the shoots on which leaves show Mg deficiency may be defoliated except for a few
leaves near their terminals. Mg deficiency increases fruit drop at harvest.

Figure 3. Magneisum deficiency symptoms on pear leaves.

Figure 4. Heat stress symptoms on pear foliage.

-8-

Heat stress symptoms on pear foliage (Figure 4) are sometimes confused with Mg
deficiency. Symptoms of heat stress (scorch) appear suddenly after a period of intense
heat. The scorch generally can be found on spur and terminal leaves of several or
more branches throughout the trees, the leaves being partially brown or black. There
is no progression of symptoms from the older to the most recently-formed leaves on
terminal shoots as with Mg deficiency. Frequently, the majority of injured leaves
drop as the growing season progresses. The Bosc variety may be more susceptible
to heat stress than other pear varieties commonly grown in New England.

Potassium (K). Figure 5 shows leaf margin burn caused by K deficiency. This symptom
can be easily confused with the leaf margin burn from calcium chloride sprays and
sometimes confused with Mg deficiency. However, unlike leaf burn from calcium
chloride sprays, the scorch of leaf margins due to K deficiency progresses from the
older leaves to the younger leaves of current season shoots as the season advances.
The scorch may turn gray in color. Fraying and tattering of the leaves may occur
due to loss of the dead areas along their margins. When the deficiency is severe leaf
drop commencing with the older leaves of current season's terminal growth, is evident
in the latter part of the growing season. Nevertheless, leaf analysis is sometimes
necessary to confirm the problem is K and not calcium chloride burn.

Figure 5. Potassium deficiency symptoms on apple leaves.

Total K absorbed and the total dry matter produced is similar for fruiting and
non-fruiting trees but in heavy-cropping trees is translocated into the fruits. Thus,
the demand of a large crop for K is great and both the tree and fruit may be deficient
in this element. Leaf injury because of K deficiency can cause pre-harvest drop and
reduce fruit size. In contrast, light cropping trees are probably much higher in K than
is needed because of "luxury" uptake.

K deficiency symptoms are apt to be more frequent in dry years because drought
conditions reduces uptake of elements.

-9-

Boron Toxicity (B) . Toxicity symptoms of this element are observed in a few orchards
each year. Symptoms occur on bearing trees sprayed with a foliar application of B,
on trees fertilized with B the year of planting, or bearing trees that received excessive
rates of B containing fertilizer. Figure 6 shows typical foliar symptoms of B toxicity.
The symptoms are characterized by loss of chlorophyll (green coloration) from along
the midrib and larger lateral veins. The symptoms are first apparent at the base of
the leaf blade. In severe cases, loss of chlorophyU is more extensive than shown in
the picture.

Boron Deficiency (B) . Occasionally B deficiency is so acute in pear trees that the
fruits become malformed and cracked (Figure 7). B deficiency on apple trees is less
common than B toxicity. It is very easy to prevent, thus it is embarassing to have
the disorder. It certainly hurts financially because all the fruit where deficiency exist
should be sold only for cider.

The most common symptom of B deficiency is found internal in fruit being characterized
by brown, round or irregular shaped lesions of about 5 inch diameter (Figure 8). The
dead cell masses become dry, hard and corky before harvest. Fruit affected with the
disorder will have a pebbled surface (particularly noticeable on Cortland), open calyx,
and abnormally dark color as they mature. However, frequently the first recognition
of the problem is excessive preharvest drop.

Figure 6. Boron toxicity symptoms on apple leaves.

-10-

Figure 7. Symptoms of boron deficiency in pear fruit.

-u-

Manganese Deficiency (Mn). This element is found deficient in several orchards each
summer. As shown in Figure 9, apple leaves having Mn deficiency have interveinal
fading of chlorophyll with the veins remaining green. In the past we have analyzed
Mcintosh apple leaves from trees showing Mn deficiency and found the leaf of this
element to be 9 to 14 ppm. Mn levels of this magnitude are critically low in comparison
to the desired standard of 50-100 ppm set by other states for apple trees.

Manganese Toxicity (Mn) is implicated with the problem of "apple measles" shown
in Figure 10. The twig from Delicious at the top of the photograph shows severe
symptoms of measles while the twig below has normal bark. Measles can severely
injure or kill young Delicious trees. An over-application of a dormant-oil spray can
induce symptoms similar to that shown in Figure 10.

Figure 9. Symptoms of manganese toxicity on apple leaves.

-12-

Figure 10. Bark on three year-old wood from Delicious trees showing measles (top
of photograph) as compared to normal bark (bottom of photograph).

:jc])e:te:jt:je4:3(c^^4:3t:

POMOLOGICAL PARAGRAPH

William J. Lord
Department of Plant and Soil Sciences

New Apple Rootstock Will Soon Be Available. Mark a new size-controlling rootstock,
one of a series of rootstocks developed by Dr. Robert Carlson, Michigan State University,
Professor emeritus of Horticulture, will soon be commercially available. Trees on
Mark (formerly designated MAC-9) are reported to be well-anchored, precocious and
between M9 and M26 in size. Thus, Mark under Michigan conditions, shows great promise
as a size-controlling rootstock that enhances early fruit production and requires no
support because of poor anchorage or brittle roots.

We have Starkspur Supreme Delicious on Mark at our Horticultural Research Station
in Belchertown but the trees are only 4 years old. Nevertheless, the trees on Mark
presently appear to be well anchored, precocious and somewhat larger than those on
M26. In contrast, unsupported Starkspur Supreme Delicious trees on M9 or EMLA27
are leaning badly or have broke at the scion-rootstock union.

It is reported that limited quantities of trees on Mark will be available for purchase
during the winter of 19 86-87. By this time Mark will have been more thoroughly tested
because it has been included in the North Central Region Cooperative Rootstock Trial
established in 1980-81 at 25 locations in the United States and 2 in Canada.

-13-

The Consumer's View of Fresh Pears
William J. Bramlage
Department of Plant and Soil Sciences

A ripe pear can be a true delicacy, yet consumption of pears ranks far
below that of fruits such as oranges, apples, and bananas. Why don't we eat
more pears? A very interesting picture emerges from a study conducted in
England, entitled "The Pear Situation 1976" and published by The Apple and Pear
Development Council. As a part of this study housewives who were regular buyers
of fruit were interviewed, including ones who purchased pears frequently, irre-
gularly, or not at all .

Why buy pears ? Consumers purchased fruit for the following purposes: as a
dessert; as a snack; for inclusion in lunch boxes or picnic baskets; and for
casual eating, such as while watching TV. The main reasons for not ordinarily
purchasing pears were that the consumers either did not like them or because
they considered pears unsuitable for certain of these purposes, especially for
inclusion in lunch boxes and for casual eating.

Pears were considered unsuitable for lunch boxes primarily because they
were thought to be too fragile, while the main objection to them for casual
eating was that you cannot casually eat a ripe pear! Unlike apples or bananas,
pears usually require a plate, a knife, and a napkin when eaten. This point was
emphasized by mothers with young children, who felt that the most satisfactory
way to serve pears to a child was to peel, slice, and core the fruit.

Selecti on . In the store the consumers were searching for a basis on which
to predict the quality of pears. The most obvious possibilities are the
appearance and the variety name. However, variety names are not conspicuously
promoted and even when they are few consumers have sufficient knowledge to
relate quality with variety. Therefore, appearance is the al 1 -important factor
in choice of pears. Yet, consumers had little understanding of what to expect
from a pear's appearance. As a result, purchase of pears was very risky. Many
of those interviewed were unwilling to subject themselves to criticism from the
rest of the family, so they tended to avoid this risk and make a "safe" purchase
of other fruit.

What is so unpredictable about pears? First, their tendency to be hard
when the consumer wants them to be soft. A substantial portion of those inter-
viewed had little idea that pears could be ripened in the home, much less
knowledge of how to ripen them. Second, there was little perception of exactly
when a pear should be eaten. Therefore, when pears were purchased it was only
in small quantities and if the purchase proved disappointing the buyer usually
skinned pears for some time afterward.

Acceptabi lity . Consumers were generally well aware of the health-giving
properties of apples and oranges, but they questioned the nutritional value of
pears. Housewives were particularly anxious to provide their children with
good, wholesome, fresh fruit and were unclear of the nutritional role of pears.

There was also an image that pears tend to be more expensive than apples,
for example, and that pears therefore were a luxury item. This image plus the
uncertainty of quality were strong deterrents to regular purchases of pears.

-14-

Quite interestingly, there was strong indication that favorable disposition
to pears was often acquired early in life. Many of the consumers who were
enthusiastic ai^out pears were strongly encouraged to eat them as children.
Children were particularly strong motivators of fruit purchase, so it seemed
reasonable to conclude that pear buying would be stimulated by giving mothers a
good reason for buying them for their children.

The Ideal Pear . The housewives interviewed found it much easier to
describe what they did not like about pears than what they did like. The most
prominent dislikes were dryness and hardness, commonly thought to go together.
Other prominent dislikes were grittiness, tendency for bruises to appear during
ripening, and browning in the core.

The majority of those interviewed were seeking a pear that had an attrac-
tive smooth skin, was juicy, and had a smooth internal texture. (It should be
noted, though, that some consumers prefer hard pears, and that in the U.S. there
is reputed to be a growing preference for hard green peas among young
consumers.) There was a preference for clear skinned, green to yellow pears with
a true "pear shape", and opposition to ones with a brown ground color, which was
associated with tough pears having a leathery skin.

Conci usions . Although this study was conducted in England and is about 10
years old, it is likely that the perceptions revealed by the interviews are
widespread and still relevant. The study strongly suggests that pear sales and
consumption could be improved considerably by better promotion and information,
and especially by providing the consumer with more consistent quality, and with
information about how to handle pears once they have been purchased.

POMOLOGICAL PARAGRAPH

Wil 1 iam J. Lord

Department of Plant and Soil Sciences

Harvest Indices . Changes in firmness of flesh, surface color, seed color, size
of fruit, ground color, ease of separation from spur, days from full bloom, the
Starch-Iodine test, calendar date and ethylene production are indices of
maturity that a grower may follow to determine when to harvest his apples.
Ethylene level in the fruits clearly is the best measure to assess maturity,
ripening and storability but our experiences with a portable instrument to
measure this gas has been less than satisfactory. Among the indices that are of
little or no value are seed color, fruit size and fruit color. The seeds may
change color from light green to brown weeks before other indices indicate
picking maturity. Surface color is of no value with red strains because their
entire surface may redden when still wery immature.

Recently, there has been renewed interest in using the Starch-Iodine Test for
evaluating apple maturity. As apples mature and ripen, the starch in the imma-
ture fruit changes to sugar. This decreasing level of starch can be measured by
treating the fruit with an iodine solution. Contact your Regional Fruit
Specialist for further information concerning the Starch-Iodine tests.

Picking at the proper stage of maturity is particularly important if the
fruit is to be stored. But this is confounded by color required for sale, type
of storage and length of storage. Therefore, there is no such thing as optimum
maturity stage for all fruit. Fruit for long-term storage should be harvested
and stored before they gain the capacity to produce large quantities of ethy-
lene. However, those intended for shorter storage can and should be allowed to
remain on the trees longer to gain extra quality and sales appeal.

-15-

DO FUNGICIDE RESIDUES AFFECT APPLE MAGGOT FLY EGGLAYING?
Susan B. Oppl, Susan L. Butkewich^, and Ronald J. Prokopy-^
Department of Entomology

In previous issues of FRUIT NOTES, we described some of our studies
on the effects of various substances on apple maggot fly egglaying. For
example, we found that a substance (pheromone) released by female flies
following egglaying deters other females from attempting to lay an egg in
that fruit (Vol. 42, No. 1). We also found that sodium chloride (table
salt) Vol. 45, No. 5) and acid rain (Vol. 48, No. 4) deter egglaying,
while calcium chloride has no such effect (Vol. 45, No. 5).

Recently, we decided to test some of the fungicides commonly applied
to apples to control mid- to late-season diseases for possible effects
of their residues on apple maggot fly egglaying. We felt that an
egglaying deterrence from fungicides applied during the months of peak
apple maggot fly activity might affect grower choice of fungicides for
use against diseases.

We tested at field rates 9 organic fungicides currently recommended
for apples and 1 fungicide (Bordeaux mixture) no longer applied to
apples. Unfortunately, our laboratory trials showed no effects of any
of the organic fungicides on apple maggot fly egglaying. Only the
inorganic fungicide Bordeaux mixture significantly deterred fly
egglaying (Table 1). Before the introduction of organic fungicides,
Bordeaux mixture was widely used as an orchard fungicide. However, it
is phytotoxic and is not compatible with many other pesticides, and thus
is no longer recommended for orchard use.

It is also interesting to note that even the fungicides which left
visibly heavy residues on test fruit (such as sulfur) or had a
disagreeable odor (such as fenarimol ) did not deter fly egglaying. We
are reminded that insects may react in ways which differ dramatically
from what we might expect.

Graduate student. Entomology

Extension Technician
^ Extension Entomologist

-16-

Table 1. Percent of arriving females attempting egglaying into
hawthorn fruits treated with fungicide or spring water control.

Experiment Rate of formulated Egglaying

material (lb/100 gal ) attempts (%)

Control - 39.2

Captan (50WP) 2.0 49.1

Control - 58.2

Maneb (80WP) 1.5 62.5

Dodine (65WP) 0.375 54.2

Control - 42.8

Benomyl (50WP) 0.375 43.8

Sulfur (actual ) 5.0 56.6

Control - 67.5

Thiram (65WP) 2.0 67.3

Control - 65.4

Metiram (80WP) 2.0 49.1

Dikar (80WP) 2.0 60.0

Control - 49.2

Ferbam (76WP) 1.5 70.0

Fenarimol (12.5EC) 3 oz. 50.9

Control - 66.7

Bordeaux mi xture 3-11 12.1*
(copper sulfate-1 ime)

*Significantly less than egglaying into control fruits.

-17-

Effects of Rootstock and Stempiece/Rootstock Combinations on Growth, Leaf Mineral
Concentrations, Yield and Fruit Quality of 'Empire' Apple Trees!

W.J. Lord, D.W. Greene, R.A. Damon, Jr. and J.H. Baker
University of Massachusetts, Amherst 01003

A study of 8-year duration was recently completed in which we studied the
vegetative growth, leaf mineral concentrations, fruiting and fruit quality responses
of 'Empire' apple trees on M26, M9, M27, M9/MM106, M9/MM111, M27/MM106 and
M27/MM111. The stempieces were 8 inches (20 cm) in length. Our summary and
conclusions from this study are below.

Growth. It was difficult to train, without temporary support, trees on M26, 9/106,
9/111, 27/106 and 27/111 because of leader leaning. Leader leaning appeared associated
with the growth characteristic of 'Empire' rather than an excessive crop load. Since
this problem also has been encountered with other varieties on M26 or interstems,
we concluded that it may be frequently necessary to provide support for the central
leader until the trees have obtained the height and volume desired.

Interstem trees on MMlll produced more root suckers than those with MM106 as
the understock. Trees on M27 produced no root suckers. The root suckering was
not particularly troublesome on the interstem trees probably because all but 2 inches
of the stempiece was planted below ground and maintained by periodic removal or
addition of top soil. Costante et al. in Vermont showed that interstem trees planted
with most of the stempiece beneath ground had less root suckers and problems
associated with burrknots on the stempieces.

Height and spread of trees on M26, 9/106, 9/111, 27/106 and 27/111 were similar,
and they were larger than those on M9 and M27. The data disagreed with the suggestion
by nurserymen that a M27 stempiece on either MM106 or MMlll will produce a tree
approximately the size of the same cultivar on M9 rootstock.

M27 appears too dwarfing to be of value under less than extremely favorable
growing conditions and a high level of management. However, Tukey in Pennsylvania
predicts off bright future for this rootstock as the industry shifts to virus-tested
rootstocks which induce high vigor.

Leaf mineral concentrations. The rootstock and stempiece/rootstock combinations
influenced leaf phosphorous, magnesium, boron, manganese, and aluminum in 'Empire'
scion foliage but the differences were small except for manganese levels in trees
on M27. Manganese level in leaves from trees on M27 was much higher than those
for trees on the other rootstock and stempiece/rootstock combinations.

This study was funded in part by grants from the International Dwarf Fruit Tree
Association.

-18-

Effects of rootstock on nutrient uptake and movement may vary among locations
due to orchard conditions, tree age, variety and crop load. Nevertheless, appropriate
preventative measures may be necessary before planting trees on M27 rootstocks
where manganese has been associated with internal bark necrosis on Delicious apple
trees.

Fruitfulness and fruit size. No rootstock or stempiece/rootstock combination
consistently influenced bloom or fruit set although it is well known that M9 rootstock
can induce early precocity and limited data show that rootstocks can influence fruit
set. The trees fruited in their 3rd growing season but yields were low until the 6th
growing season. After 8 growing seasons it was found that trees on M26, 9/106 and
27/106 were more productive than those on 9/111, 1V19 and M27. However, when
fruitfulness was related to trunk girth, production efficiency did not differ among
the trees on the various rootstock and stempiece/rootstock combinations. There
was no consistent influence of rootstock or stempiece/rootstock combinations on
fruit size of 'Empire' in this study.

Individual trees within the rootstock and stempiece/rootstocks combinations became
somewhat biennial. Heavy cropping during the 7th or 8th growing seasons combined
with the tendency of 'Empire' to produce small fruit, indicated the need to chemically
thin this variety to enhance fruit size and to prevent biennial bearing.

Fruit maturity. Fruit from trees on 27/111 ripened later than those from trees on
the other rootstock and stempiece/rootstock combinations. However, the delay in
ripening was small and probably of no commercial importance.

Data cited above indicated that IV127 and M9 were equally suitable as stempieces.
No interstem combination showed an advantage over the lower-priced singly-worked
trees on M26 although MMlll is reported to be adapted to a greater variety of soils
than M26. We concluded that interstem trees will require a higher level of management
that is usually given trees on more vigorous size-controlling rootstocks in northeastern
United States.

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CHA^<LESTOWI^!. MASS.