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| UNITED STATES DEPARTMENT OF AGRI ICULTORE, hi

In Cooperation with the Oregon and Washington Agricultural Fcuditcan
2 Stations

DEPARTMENT BULLETIN No. 1434

| Washington, D. C. Vv November, 1926

CRANBERRY DISEASE INVESTIGATIONS ON THE PACIFIC COAST

By Henry F. Bain, Assistant Pathologist, Office of Fruit Diseases, Bureau of
Plant Industry -

CONTENTS
Page Page
AETLOGUCHION St 200 We EYE ee CRs 1 | Diseases of berries in storage._..._..--_-----
General considerations_--_--_----------- 1) |) Experimental worke2: = S20 ey Ae 9
Climaticiconditionsss2222. 2 eos ee 2 JIN TY BO KSA Seay a RS SUL AN aca a 9
imsect spestss. a. See oe we ot eter era 3 Preliminary experiments____--_----- 1... 2 10
TID SINS SERGE es a Ny SER eC Se eC SE 2 Experiments to determine time and num-
Diseases of the cranberry plant__+----------- 5 ber of applications of Bordeaux mix-
Red leaf spot and black stem spot----_--- 3 ALU gaps mS I SEE A GE Pa es OS Soe es 12
IEVOS O= 101 OO 1 ee ea aan eet hae en Es 4 WD UWShIMNCLEXPenIUMe MS we yee ee el 16
HAalSesl OSS OTe ee ns 28 iin ae eis en ie 5 Cold-storage experiments_...__._--_-__- 17
BPS se nt ec Ua a ag 5 | Relation of weather to keeping quality___-_-- 19
Wentuniavleatispotee mins ie Te v3 6 | Culture work with cranberry rot fungi____-- 21
Sclerotinia tip-blight___..____-_....-.-___ 6 INE TAME DORE CS 2 2 aik Se Be NE 21
‘Diseases of berries in the field___.___._.----- 6 Greentberries secs ae Ss a a ae 26
Sclerotinia hard rot (cotton ball) and tip- SUPT TIN ay Ty en RR ates ie ie late Seva ee 26
Deh PLB ee a Se Oy ed iteratwre teibe de 4 eet Ar A AAA ENE ee a 28
BlAckIsMoL on te truth. ey Pe an ae 8
AVI OTe e] OLS me etek ne eet 8
INTRODUCTION

Although the diseases of the cultivated cranberry (Vaccinium mac-
rocarpon) “have been studied rather intensively since 1901, most of
the work prior to 1922 was done in New Jersey, Massachusetts, and
Wisconsin. This bulletin summarizes the results of a four-year study
of cranberry diseases inthe States of Oregon and Washington. The
imate of the Pacific coast region is so different from that of the older
Been bemy -erowing sections that important modifications in cultural
practices have been found necessary. Since cultural methods have
avery important relation to the pathological problems considered in
this work, it seems essential to outline briefly the general methods
at present followed in this region, with particular reference to the
peuite in which these methods differ from those of the older cran-

erry sections.
GENERAL CONSIDERATIONS

_ Cranberry growing on the Pacific coast is a comparatively recent
eee y: its extensive development having been started in 1912 to
1915 (4).1. The problem of determining the most successful varieties

1The serial numbers (italic) in parentheses refer to ‘‘ Literature cited,” p. 28.
102485—26;——1

4. BULLETIN 1434, U. S. DEPARTMENT OF AGRICULTURE

and sometimes distorted in shape. The hypertrophied zone may
extend several centimeters along the stem, but the latter often con-
tinues its normal growth beyond the lesion. The disappearance of
red stem lesions later in the season, consistently followed by the ap-
pearance of black stem spot in the same vines, leads to the belief
that the fungus causing the latter disease often invades the red spots
and produces its fruiting bodies in the same lesions. Much more
frequently the black-spot fungus gains entrance through the red spots
on the leaves and proceeds to attack the stem, through the petiole,
without the appearance of any symptoms of reddening and swellin
associated with Exobasidium In this case the stem lesions are blac
from the beginning, and immature perithecia appear early. The in-
fected leaves are entirely killed, shrivel rapidly, and drop off easily,
a result that Exobasidium apparently does not cause when acting
alone. The minute immature perithecia are frequently borne on the
petioles of infected leaves and have occasionally been found on leaves.
Ascospores are produced the following spring.

The latter type of infection is the rule in severe attacks of the dis-
ease. The first indication is always an epidemic of red leaf spot.
If weather conditions continue favorable for any length of time the
leaves are completely killed by the invasion of the black-spot organ-
ism and turn brown in a manner similar to severe fireworm injury.
Close observation at this time will show numerous black stem lesions,
usually centering around leaf scars, on both runners and uprights.
The lesions generally encircle the stem entirely, though they may be
confined to the side on which infection occurred. In severe cases
most of the uprights may be killed by the black-spot fungus.

Control.—Red leaf spot and black stem spot are very dependent
upon weather conditions. The disease may appear during a period
of rainy or misty and cloudy weather at any time after vine growth
has started. It is more severe in shaded portions of a bog and in
sheltered places where air drainage is poor. The disease is rarely
severe in large plantings of producing vines and consequently rarely
warrants control measures other than cutting back the surrounding
brush and trees to give better air drainage and light. That it may be
controlled by Bordeaux mixture was demonstrated on the Fieselman
bog, at Columbia Beach, Oreg., in 1923. <A portion of this bog was
so severely attacked late in July that all the uprights were killed.
Beginning about the 1st of August, several applications of 3-3—50
Bordeaux mixture were made at frequent intervals. New uprights
which grew from below the old dead ones were kept free from the
disease and matured normal fruit buds the same season.

ROSE-BLOOM

Rose-bloom, caused by Exobasidium oxycocct Rost., is occasionally
found in Washington and Oregon. Shear (6, 8) has noted that this
fungus is erratic in making 1ts appearance in all the regions where it
occurs. The disease was fairly prevalent in 1922, but could scarcely
be found in any of the other three years of these observations.
It apparently causes no appreciable injury in this section, since the
bog most severely affected in 1922 yielded a crop of berries larger
than the average of producing bogs that year, and the crop was also
good the following year. The disease appears soon after the vines start

4

CRANBERRY DISEASES ON THE PACIFIC COAST 5

growing. “The axillary leaf buds, which usually remain dormant,
are attacked by the disease and produce short shoots with rather
close, enlarged, swollen, and distorted leaves which are pink or light
rose colored” (6). No particular control measures have been found
“necessary, although it is possible that the systematic spraying with
' Bordeaux mixture practiced within recent years may be partly respon-
_ sibie for its rarity.
FALSE-BLOSSOM

The false-blossom disease of the cranberry (7, 1/4) is present to some

_ extent in practically all Pacific coast bogs planted with Wisconsin

_ vines and has been found on the Bennett Jumbo, Searls, and Pro-

lific varieties. The writer has not found it on any Cape Cod or

New Jersey varieties, even when the latter were planted adjacent

to affected Wisconsin vines. The form of disease usually met with

here is the characteristic witches’-broom growth with flowers upright
and dark red in color, receptacle enlarged and petals dwarfed, but no
proliferation of floral organs. Berries frequently mature on affected
plants, though they are dwarfed in size. Careful observation disclosed

_ ho evidence that the disease spreads under the conditions prevailing
on the Pacific coast.

) False-blossom is demanding a great deal of attention in eastern
cranberry districts, and evidence is accumulating that the disease is
infectious. The behavior of the disease on the Pacific coast is there-

fore of unusual interest. Several newly planted bogs of the Bennett
Jumbo variety came under the observation of the writer and an
opportunity was thus offered to watch the development of the disease.
By the end of the second growing season diseased plants could be
easily located by their upright witches’-broom appearance. Such
plants were scattered at random over the bog wherever cuttings from
diseased plants happened to have been planted. A year or two later,
however, when the bog had become thoroughly vined over, it was
exceedingly difficult to locate these diseased plants. Despite the
fact that numerous sources of infection were originally scattered
throughout the bog, the disease evidently did not increase in abun-
dance, but, on the contrary, actually appeared to decrease as the
affected vines became imconspicuous in the tangle of healthy vines.
Obviously, cuttings from such a bog will carry a certain number of
diseased vines to new plantings; and since practically ali new plant-

ings for several years past have been made from cuttings produced
locally, it is not surprising that the disease is so universally present
among affected varieties. The disease is no more prevalent on the
whole in the oldest affected bogs in the region, however, than in those
planted very recently, a fact that would be difficult to explain if the
disease spread actively. Under Pacific coast conditions this disease
at present exerts no appreciable influence on the yield.

RUST

No evidence has been discovered that rust, caused by Puccinias -
trum myrtillt (Schum.) Arth., is of economic importance. Infected
leaves may be found here and there in numerous bogs, but never in
abundance. Usually the only evidence of the presence of this fungus
is the appearance of a few yellowish uredinial pustules on the lower
surface of a leaf.

6 BULLETIN 1434, U. S. DEPARTMENT OF AGRICULTURE
VENTURIA LEAF SPOT

A disease that is prevalent at times and alarms some growers is
the Venturia leaf spot. It is characterized by conspicuous black
spots on the lower surfaces of leaves. The black color is due to
closely packed superficial perithecia of the causal organism. There
is no definitely outlined diseased area in the leaf, which in many cases
shows no symptoms whatever of the presence of the fungus other than
the perithecia above referred tu; in other cases shght discoloration
may be noticed on the upper leaf surface.

Venturia is confined to leaves, so far as known, and is of little eco-
nomic importance.

SCLEROTINIA TIP-BLIGHT

Sclerotuma oxycocct Wor. causes both a tip-blight disease of the
plant and arot of the fruit. Since the tip-blight is of relatively
slight importance compared with the rot, this disease will be described
under the latter heading.

DISEASES OF BERRIES IN THE FIELD

Field rots are of comparatively little importance in the Pacific
coast region. Species of Botrytis often rot berries which have been
injured by fireworms or otherwise, and a few berries rotted by
Phomopsis may sometimes be found at picking time. Black spot of
the berry may occur in isolated patches. The only rot that ever
becomes serious in the field, however, is the Sclerotinia hard rot or
“cotton ball.”

SCLEROTINIA HARD ROT (COTTON BALL) AND TIP-BLIGHT

The symptoms of Sclerotinia hard rot or cotton ballin the berry are
easily recognized. At harvest time the diseased berries fail to ripen
normally, rarely showing any red color. Soon yellowish brown areas
appear in broad bands running lengthwise of the berry and rapidly
spread until the whole berry is uniformly yellowish brown in color.
‘The interior of diseased berries is filled with the cottony white
mycelium of the fungus, this condition giving rise to the local name
for the disease.

Sclerotinia is usually most abundant in young bogs or in those
which are made up largely of young growth following heavy pruning
and resanding. The prevalence of cotton ball during any given season
depends toa large extent upon favorable weather conditions occurring
at critical times in the life history of the fungus. The total annual
loss from the disease probably never is large, but occasionally it
becomes epidemic in areas of from 1 to a few acres and may affect
90 per cent or more of the berries in these areas. Berries rotted by
this fungus have to be sorted by hand, necessarily an expensive
operation.

The life history of the fungus (Sclerotinia oxycocct Wor.) causing
hard rot and tip-blight will be given somewhat in detail, since there
is no published account of the disease based upon continuous obser-
vation in the field. Mature apothecia were first found under natural
bog conditions on May 16 in 1923 (others evidently had matured
earlier than this), on April 1 in 1924, and on April 18,1925. It may
be stated, then, that.the apothecia mature as a rule in April and

CRANBERRY DISEASES ON THE PACIFIC COAST 7

early in May, especially during the prolonged rainy periods which
' are likely to occur at this time of year. Mature apothecia are 1
- centimeter or less in diameter and are borne on slender stalks that
_ vary from about 1 to about 5 centimeters in length. Numerous
_ apothecia sometimes arise from a single sclerotium. Sclerotia wholly
or partly buried in the fallen leaves and trash beneath the vines seem
_ to produce apothecia more freely than those in other situations.
They are infrequently found in piles of rotten berries containing
' numerous mummies and are very difficult to force artificially.

Little is known concerning the infection of the vines by ascospores.
The latter are produced before or just as vines begin growing and
infect the new growth, usually the uprights. No macroscopic ev1-
dence of infection is visible until the sudden wilting of uprights
occurs about the time the bog is coming into bloom. ‘The infected
uprights, now nearly full grown, collapse a short distance back of
their tips, become brown and shriveled, and soon the dead stems are
covered withthe grayish white powdery masses of conidia. Conidia
are borne chiefly on the curved portion of the stem formed where the
upright has collapsed. Flowers, pedicels, and leafstalks are also
occasionally attacked, and the characteristic grayish masses of conidia
are produced along the bent and curved parts of these organs.

The tip-blight stage of this disease rarely affects a sufficient pro-
portion of uprights to cause noticeable injury to the vines or to the
crop. Diseased tips are rather hard to find even when relatively
numerous, because they are so inconspicuous among the erect healthy
uprights. The first tip-blight observed in 1923 was on June 12, in
1924 on May 21, and in 1925 on May 22.

The time of conidial production of this fungus coincides closely
with the blooming period of the cranberry. Conidiospores unques-
tionably are carried over to and infect the berries during the blos-
soming period. Infected berries continue their normal increase in
size all summer without showing any external evidence of infection.
The fungus may easily be seen, however, upon cutting open an
infected fruit any time after it has set, the seeds being invested with
the cottony mycelium. This relation between fungus and berry is
maintained until the latter reaches mature size—such berries fre-
quently average somewhat larger than uninfected ones—when the
fungus suddenly becomes very active and rapidly invades all the
surrounding tissues, and the whole interior of the berry becomes filled
with the cottony mycelium. The further development of the fungus
takes place rather rapidly if other contaminating rots do not over-
run the Sclerotinia. The flesh of the diseased berry becomes filled
with hyphe, which eventually develop into a hard, compact, black
sclerotium. The interior of the berry and some of the tissue mid-
way between the four walls of the seed cavity rot away entirely, so
that the sclerotium as finally formed consists of circular plates of
sclerotial tissue at either end of the berry, connected by four riblike
formations of the same tissue which have replaced the fruit pulp at
its junction with the four seed-cavity walls. The fruit epidermis
usually remains intact over this sclerotium throughout the winter,
the whole forming the characteristic mummy. These mummies some-
times remain attached to the uprights all winter. The following
spring they produce apothecia and start the life cycle over again.

§ BULLETIN 1434, U. S. DEPARTMENT OF AGRICULTURE q

Control—The disease is most abundant when three conditions|
prevail, namely, prolonged wet periods during the time the apothecia
mature, rainy periods during blossoming time, and a plentiful supply
of mummied berries to start the tip-blight infection. As already
noted, hard rot rarely is troublesome on older bogs. This may be)
partly because these bogs are picked clean regularly and very few
mummied berries are left to carry the disease over winter. Clean |

picking is recommended as an important control measure. Some |
evidence has been obtained that in the ‘‘hook”’ stage of the vines |
(just as they begin to bloom) Bordeaux spray helps to reduce berry |
infection, and it is believed that a thorough application of Bordeaux |
mixture to the vines just before ascospore discharge occurs will help

to prevent tip-blight and thus reduce the possibility of berry infec-
tion; but all attempts to prove this experimentally have failed because
of the impossibility of locating in advance a place where the disease
was going to be epidemic.

BLACK SPOT OF THE FRUIT .

Under favorable weather conditions the fungus causing black stem
spot sometimes attacks berries, producing conspicuous black sunken
spots that vary in size from very small spots to lesions that involve
more than half of the berry. The entire spot is filled with innumer-
able young fruiting bodies of the fungus. Berries affected by this
spot are found only in sections of the bog heavily diseased with stem
spot, but are rarely noticed prior to harvesting. Black spot is readily
distinguished from the black rot of the fruit caused by Ceuthospora
lunata by the fact that it develops before harvest and is strictly a
spotting disease, with spots decidedly sunken. When no secondary
fungi follow the black-spot organism, the healthy portion of the berry

remains perfectly sound and normal, whereas black rot involves the -

entire berry.

Mature perithecia of the black-spot fungus were not found on the
berry. Although the immature perithecia are present in large num-
bers in all spots, the berries become so overrun with other fungi
before spring (the normal time for the ascospores to develop) that
it is impossible to find fruiting material of the fungus.

Control measures for black fruit spot are the same as for black
stem spot.

MINOR FIELD ROTS

¢

Botrytis, as noted above, rots berries which have been injured in
the field. Such berries become softened and yellowish in color. The
fungus often fruits around the edges of wounds made by the fireworm.

homopsis rot sometimes develops shortly before harvest. Berries
rotted by this fungus are rather firm and leathery and are likely to
be yellowish to reddish yellow in color at this season of the year.
Phomopsis is better known as a storage rot, but numerous cultures
showed that this early developing rot is due almost exclusively to
this fungus. :

Exobasidium vaccunvi infrequently attacks the fruit also, producing
somewhat raised circular red spots upon green berries. Curiously
enough, this fungus produces its spores in the interior of the fruit,
upon the wall lining the seed cavity, which is known to have stomata.

CRANBERRY DISEASES ON THE PACIFIC COAST 9

DISEASES OF BERRIES IN STORAGE

' Increasing attention has been given within recent years to the
losses of cranberries in storage resulting from fungous diseases and
other causes (1,5,9,10). In the Pacific coast region the problem
is predominantly one of storage rots. From the point of view of the
erower there are two periods of storage losses, the first including
decays developing in the warehouse before berries are shipped and
the second those occurring in the markets. ;

It is now well known that the development of fungous diseases
can be materially reduced by care in harvesting and handling the
crop and by storing the berries in cool, weil-ventilated warehouses.
With the best of attention to these details a certain. degree of
deterioration, varying from season to season, always takes place
before the berries are milled and shipped to the markets. This loss
is taken directly by the grower, the spoiled berries being removed in
the processes of milling and sorting. The magnitude of the loss
suffered prior to shipping often is not fully realized.. It was found
by actual count of representative samples of berries to vary from 5
per cent to more than 20 per cent in the storage experiments of
1924, these tests including three varieties from different bogs, and
representing various spraying schedules. (See Table 8, p. 14.)

Rots develop much more rapidly after berries have been milled,
Pacied, and subjected to the adverse conditions of shipping and

andling in the markets. Given a sufficient extent of fungus
infection to begin with, a shipment of berries leaving the grower in
excellent condition may be absolutely unsalablé in the markets a
short time later. The effect which a series of such shipments will
have on the good will of the trade should be evident (3). Where
experience has shown that, despite all possible care in harvesting
and handling, an excessive percentage of storage and market rot
develops in frequent years, the only recourse available to the pro-
ducer is to prevent the initial infection of berries by putrefactive
fungi. This condition may be said to exist in a general way in the
entire Pacific coast region.

Storage rots are caused by a number of different fungi. The
symptoms produced by most of them, however, are so nearly identical
that it is practically impossible to determine by inspection alone
the fungus responsible for the rotting of a particular berry. Again,
these fungi are similiar, in that they infect berries in the field before
harvest. Since the effect on the berry, the time of infection, and the
control methods are so much alike, these fungi will be here treated —
as a class, and the specific organisms involved will be reserved for
future consideration. The major part of the experimental work
described in this bulletin was concerned with controlling storage rots.

EXPERIMENTAL WORK

METHODS

Bordeaux mixture? has always proved to be the most effective
fungicide for cranberries and therefore was used throughout these
experiments, except for a few tests conducted with lime-copper dust.

*For descriptions of the methods of spraying cranberry bogs, the reader is referred to publications
by C. L. Shear (8) and H. K. Plank (4). The commercial Bordeaux preparation used in 1924 and 1925,
which gave practically as good results as the freshly prepared mixture, consisted of pulverized bluestone
and lime in separate containers.

102485—26t 2

10 BULLETIN 1434, U. S. DEPARTMENT OF AGRICULTURE

The standard procedure followed in making the test was as follows:
Early in the season plots were marked off of sufficient size to insure
an adequate quantity of berries for the storage tests. Spray was
applied to these plots as noted in the various tables. One plot
(in some cases two or more) was held as a check and received no
spray throughout the season. The berries from the different plots
were harvested by experienced pickers, care being taken to avoid
berries from the fringe area at the junction of plots. The samples,
properly labeled, were hauled to the warehouse and stored with the
remainder of the crop until ready for shipment. They were then
milled and sorted in the usual manner by experienced employees
and packed in standard shipping boxes. In the earlier tests a full
box was used for each unit, but later three and four samples, respec-
tively, were put in }4-barrel and half-barrel boxes. Usually three
units were taken from each sprayed plot, in order to allow three suc-
cessive examinations to be made without handling any sample more
than once. The boxed berries were then shipped to some market
and held in storage for varying lengths of time, usually in a commer-
cial fruit warehouse. In 1922 the storage tests were conducted in
San Francisco, Calif., in 1923 and 1924 in Portland, Oreg., and in 1925
in Washington, D.C. This form of procedure was followed in order
to give the experimentally sprayed berries the same kind and degree
of handling that commercial berries receive.

Franklin’s 7-sample method was used throughout the experiments
to determine the percentage of rot (2). Seven cups of berries were
taken from each Igt to be examined, two from near the top of the
box, three from the center, and two near the bottom, the samples
being spaced equidistantly with reference to one another. Rotten
berries were carefully sorted out of these samples, and both decayed
and sound berries were then counted. The percentage of spoiled
berries thus found was considered to be representative of the amount
of rot in the box as a whole.

PRELIMINARY EXPERIMENTS

The spraying experiments outlined for the first season (1922) were
based directly upon the schedules recommended for eastern cranberry
bogs (8). This program calls for three, or in some cases four, appli-
cations of Bordeaux mixture—(1) at the hook stage, (2) after blos-
soming, (3) two weeks later, and (4) not later than August 15. In
addition to these an earlier application of spray was to be made to
control the Sclerotinia disease. The tests were made on a section of
the Howes variety on the Dellinger bogs at Clatsop, Oreg. It soon
became evident that difficulties would be encountered in fitting this
schedule to the bog selected for the tests. The Sclerotinia spray was
applied on May 27 when new uprights were just starting to grow.
Aiter this time the development of the vines was exceedingly irregu-
lar, no definite hook-stage period ever appearing. The spray sched-
uled for this time was finally applied on June 22, after some bloom
had appeared all over the bog, but most of the uprights were in the
hook stage or an even earlier state of development. Blooming con-
tinued general over the bog for more than six weeks. The after-

11

CRANBERRY DISEASES ON THE PACIFIC COAST
blossom spray was applied on August 6, despite the fact that many
flowers were still in full bloom. Meanwhile the earlier berries had
almost matured, and it was considered inadvisable to make any
further applications of spray. ;

The above account is given in some detail because subsequent
experience proved that irregularity of growth and blooming is typical
of cranberries in this section. Some varieties begin blooming earlier
than others, and the blossoming period is always comparatively long
drawn out, even in bogs with a single variety of uniform age and
growth.

The results of storage experiments with berries from these plots are
shown in Table 1.

Tap ie 1.—Percentage of rot developing in storage in cranberries from experimentally
sprayed plots in 1922

[ Berries were scooped Oct. 9 to 15, screened Oct. 15, and shipped to San Francisco, Calif.. Now. 15) Dhe
first spray was applied May 27, when new vine growth was starting, the second (hook stage) June 22,
and the third (after blossem) Aug. 6]

DREADS eee ee a ET I UT

Sprayed with Sprayed with ;
homemade Bor- homemade Bor- 5 eee ods ee ae
deaux mixture, deaux mixture, Bordeaux’ tunis:
eae with ast 4—4-50, with eae fred eascQune
oil-soap spreader, sein spreader, ’ ’
Date of examination Check 2-50 Check 34-100 spre dek
of storage material lot, not lot, not
°" | sprayed sprayed
First First First
Second 2 Second ; Second ;
and third second. and third second, and third second,
eae ee and third RO and third |" op rays \and third
Bray sprays prays | sprays Pray. sprays
INGO 17 Se eee ee 6 3 2 1 3 Si ae a ear 4
INOW 202s eee 8 6 3 7 5 se | Reppert 10
WICC LD ee en 9 al 4 13 8 8 13 10

This series of tests was inconclusive because the checks exhibited
excellent keeping qualities. Some other storage experiments, how-
ever, brought out more valuable facts. Ina test comparing the keep-
ing qualities of cranberries from bogs (1) sprayed regularly with
Bordeaux mixture, including two applications in 1922, (2) reflowed
for fireworm but never sprayed, and (3) neither sprayed nor reflowed,
the results shown in Table 2 were obtained.

TABLE 2.—Percentage of rot developing in storage in cranberries from sprayed,
reflowed, and untreated bogs in 1922

~

Bog regularly |, Bog reflowed in 2 Ghee nelthey
sprayed with | successive years; ue ana th
Bordeaux mix- no Bordeaux SBRaye : ee
; aa ae ture mixture Bordeaux mix-

Date of examination of storage material ture
Howes Searls | Howes Searis Howes Searls
variety | variety | variety | variety variety | variety
BING Of eae a OG RES ERS (By te ee 16 23 18 20
DR ON ee IA pan ee a Le ae Att ea ea SANG eb acs aL 36 43
TB Yerevan Mia a ACR es VAMOS acs IEA ae ca ES eh 52. | 60 40 52

12 BULLETIN 1434, U. S. DEPARTMENT OF AGRICULTURE

Table 2 shows that both unsprayed begs produced very poor berries,
suggesting that continuous spraying greatly improves the keeping
quality of the fruit while reflowing tends to increase the development
of rot. At the same time, however, it is to be noted that the three
bogs represented in this test being widely separated were not exactly
comparable.

In another experiment in 1922, berries of the Bennett Jumbo vari-
ety from a bog not sprayed in previous years were used. One plot
received two applications of Bordeaux mixture (hook stage and after
blossom) and the other was not sprayed. The results of the storage
tests are given in Table 3. )

TABLE 3.—Percentage of rot developing in storage in Bennett Jumbo cranberries in
1922 from bog not sprayed in presious years

Sprayed
with
Bordeaux) Check,
Date of examination of storage material mixture not
June 15 | sprayed
and
July 20
ISSO) gy de SE il tg 28) SUL re MGA. ONDA cI DENY RSP a WE I LN AUN ie 17 18
Decrease eA 2 ee 02 SE COT ET eae ee EY 30 38.1

Table 3 shows that a bog that was not sprayed year after year
produced berries of poor keeping quality. The applications of Bor-
deaux mixture as made in 1922 served to improve the keeping qual-
ity to some extent, but the results were not entirely satisfactory.

The year 1922 was on the whole a good keeping year for commer-
cial berries. Observation showed that more trouble developed in
such varieties as Searls and Bennett than in McFarlin and Howes, sug-
gesting that under the local conditions there may be considerable
variation in the susceptibility of different varieties to fungous rots.

As a result of the experiments and observations of the first sea-
son it seemed apparent that spraying with Bordeaux mixture as a
rule reduced storage losses. Bogs sprayed year after year with Bor-
deaux mixture produced berries this season which kept well, while
those from some bogs not sprayed in past years developed a much
greater degree of rot. Certain varieties exhibited keeping qualities
superior to others. It became clear that future studies should be
along the lines of determining the necessary number of applications
of Bordeaux mixture, the proper times to make these applications, —
and more intensive control work with varieties appearing to be most
susceptible to rot-producing fungi.

EXPERIMENTS TO DETERMINE TIME AND NUMBER OF APPLICATIONS OF
BORDEAUX MIXTURE

The results obtained in an extensive series of tests with various
combinations in the time of spraying are given in Tables 4 to 9,
inclusive.

CRANBERRY DISEASES ON THE PACIFIC COAST

13

TaBLE 4.—Percentage of rot developing in storage in cranberries from West
bog, West, Oreg., in 1923

Berries were screened Nov. 5 and shipped to Portland, Oreg., Nov. 6. The first spray was applied
June 20 (hook stage), the second on July 10 (after blossom), and the third Aug. 1, when berries were one-
half to three-fourths grown]

Sprayed with Bordeaux
mixture, 4—4-50
a: Pah : Check,
_ Variety and date of examination of storage material First not °
second Second sprayed
eal ils and Third | SPtay
: third spray
third Sane
sprays Saray
Searls:
TD XY 3 TS Ses a op el Ye es ee BN Pl a Ua enc 38
aI ERT Deets sun AL SR aD hs AE as LN AG a ie ce aga ee lh 61
AEG Ty sree Lek Bes Se AE Pe UE eee Le fe SRE es BG gate ke ELS 7
Howes:
DLS YeA a EGE gis 8 22 ey 8 Ae Be Oe Ai ae Se ees a 8 10 i a en 26
AI AO) EUR SS OE gr a ia ere a ee 11 15 23 30
BIBL SB ae ee ee pee te YA cs et Uh INS adh oe LE 20 21 35 52

TaBLE 5.—Percentage of rot developing in storage in cranberries from Poole bog,
Carnahan, Oreg., in 1928

[Berries were picked Oct. 20 to 30, screened Nov. 5, and shipped to Portland, Oreg., Nov. 6. The first
spray was applied June 5 (hook stage), the second July 9 (after blossom), and the third July 31, when
berries were about three-fourths grown]

Sprayed with Bor-
deaux mixture,
44-50
i) Check,
Variety ate of examination of storage material] . First not
| d * | sprayed
First and! second,
second | and
sprays third
sprays
SGArIS ete tae el wee Fe ea ak PUES OD ey eA an a ENN 42 40 75
PBS ETAM GC Gye eee th AE Sr ae CGC) EME eI NSIS EP UE LI i 33 if

TaBLE 6.—Percentage of rot developing in storage in Bennett Jumbo cranberries
from Pilkington bog, Clatsop, Oreg., in 1923

[Berries were hand picked Oct. 1to 5, screened Nov. 5, and shipped to Pertland, Oreg., Nov. 6. The
first spray was applied May 18, when new vine growth was starting; the second June 6 and 7 (hock
stage); the third July 12 (after blossom); the fourth July 26 and 27, when berries were one-half to
three-fourths grown]

Sprayed with
Sprayed with homemade homemade Bor-
Bordeaux mixture 44-50, deaux mixture,
with fish-oil-soap spreader 4-450, with ca-
sein spreader
: 2 ore Check,
Date of examination of storage material | | ct
First, ime sprayed
second, | cecand, Third pecan
third, arial | and eval: Fourth
| and fourth | fourth | fourth | SPFay
fourth aanere sprays ean
sprays | ‘Prays | lingam
| | te
1D (5-65) Oia Sa lee eA See ALAR EOL DART MOS, 9 10 | 13 il 21 18
Erie ete R AS SRE OS SOE SANE OR AU! HH 6 | 19 | 23 ty pbetiahe cil lee 30
BODE LUN OTIEE Je CUT TENT kia 21 | 27 | 30 26 | 52 42

14 BULLETIN 1434, U. S. DEPARTMENT OF AGRICULTURE

In the experiment shown in Table 6, duplicate series of sprays
were applied on a bog infected with Sclerotinia the preceding year,
in the hope that one of them at least would cover a concurrent out-
break of the disease. The plots extended entirely across the bog.
The vines on the higher side of the bog bloomed two weeks in advance
of those on the lower side, interfering greatly with the problem of
applying the spray at given stages in the development of the plants.
No Sclerotinia appeared. The average of rot in two samples is given
in each case.

Another unsuccessful attempt was made to catch an outbreak of |
Sclerotinia in the experiment shown in Table 7. |

|

TasLe 7.—Percentage of rot developing in storage in Bennett Jumbo cranberries —
from Fieselman bog, Columbia Beach, Oreg., in 1923 |

[ Berries were hand picked early in October, screened Nov. 5, and shipped to Portland, Oreg., Nov. 6,
The first spray was applied May 3, when new vine growth was Starting, the second June 1 (hook stage).
the third July 1 (after blcsscm), and the fourth July 20, when berries were one-hali to three-fourths
grown. Homemade Bordeaux mixture 4-4-50 with fish-oil-soap spreader 2-50 was used]

i
|
|

aL : i Check not Check not
Date of examination of storage material Sprayed sprayed Sprayed sprayed
Pap Kp ACT gt sn pee Mie LS ee LA te a | 21 46 7 26

Analysis of the preceding tables shows that spraying with Bordeaux
mixture reduced the percentage of storage rot in all instances except
those in which the first spray was put on after the blossoming period.
In the latter case the keeping quality was sometimes improved to a
lesser extent, but very little benefit was derived from the final spray
alone. The percentage of rot was reduced approximately one-half in
all plots receiving the spray at the hook stage.

TasBLE 8.—Percentage of rot developing in storage in cranberries experimentally
sprayed in 1924

[Berries were screened Nov. 10 and 11 and shipped to Portland, Oreg., Nov. 20]

Sprayed with Bordeaux mixture

! paves 4 Check
Variety, bog, and date of examination of Birst First, Second Not Q
storage material First and serene Second; and Third |sprayed
spray | second thira | SPrey third | spray
sprays sprays sprays
MeFarlin, Pilkington bog: !
Nov. 10 (before screening) ~----_-----____- 8 i 8 12 10 9 10
Dec. 2) Giter storare) Me ok ee ENE vi 4 6 9 1a 12 13
Bennett, Schimpff bog: 2
IN‘OVARLONGDeRORE SEMe emi m g) see ws ee ae OL | eee ae 6 5 16 18 26 21
DEG ZN (AlLET:SEOTASE) 22 Wie Ree ee ieee 14 7 6 25 22 31 30
Sear!s, West bog: 2 |
Nov. 10 (before screening)_-_.----_-______ 12 fo) Pocdlle aval gL eS EeR EE ae Pin Ne ARN ATA L 18
Wee. 2) (alter Storage) sn. oe eo wie eee | 25 OT SSE he ACT NU OA TN ZU 29

1 First spray applied June 12 at hook stage; commercial Bordeaux mixture, 4-4-A0. Second spray
applied July 29, after blossom; homemade Bordeaux mixture, 4-4-50; soap, 2-0. Third spray applied
ue. 25; berries nearly grown; homemade Bordeaux mixture, 4-4-50; soap, 2-50. Hand picked Oct. 11

0 16.

? First spray applied June 11 at hook stage; commercial Bordeaux mixture, 4-4-50. Seccnd spray
applied July 30; some blossom, srme berries one-half grown; commercial Bordeaux mixture, 4-4-50.
Third spray applied Aug. 22; berries one-half to three-fourths grown; commercial Bordeaux mixture
4-4-50. Scooped Oct. 17 and 18.

3 First spray applied June 11 at hook stage; homemade Bordeaux mixture, 4-4-50. Second spray ap-
plied Aug. 1, after blossom. Scooped early in October.

CRANBERRY DISEASES ON THE PACIFIC COAST PBs

The final Bordeaux spray, applied on most of the bogs in this section
- about the first of August in 1923, remained adherent to the vines and
berries so persistently that in many cases pickers objected to harvest-
ing them. This fact, in conjunction with the observation: that the
final spray in itself apparently had little value, led to an alteration
in the subsequent recommendations given the growers. The new
program called for only two applications of Bordeaux mixture, one
at the hook stage, the other immediately after blossoming.

Meanwhile further experiments were performed to procure additional
data on the adequacy of the schedule recommended, with the results
shown in Tables 8 and 9.

The tests in both 1924 and 1925 clearly demonstrated that the
new schedule was justified. There was a sharp increase in the
percentage of rot developing in berries from plots not receiving
the hook-stage spray compared with those from all plots which had
received it, this being more striking in 1924 than in 1925. Berries
receiving both preblossom and after-blossom applications uniformly
held up in storage practically as well as those receiving the additional
third spray. Every lot which had received two applications of
Bordeaux mixture in 1924 was in good marketable condition after
three weeks of storage, with the possible exception of the Searls vari-
ety. In the 1925 tests the berries were in transit for 314 weeks, dur-
ing which time the twice-sprayed lots developed from 2 to 6 per cent
of rot, while the berries from plots not receiving the hook-stage spray
showed a higher percentage, ranging up to 14 per cent in Bennett plots.
After an additional storage period of one month 11 per cent was
the highest proportion of rot found in any standard-sprayed lot,
whereas many of the lots originating from plots receiving no hook-
stage spray had more than 20 per cent of rotted berries. The supe-
rior keeping quality of the former group became even more pronounced
as the storage period was increased. In other words, the hook-stage
and after-blossom applications of Bordeaux mixture controlled storage
rots satisfactorily under conditions as severe as commercial berries
are ever subjected to in a well-reculated marketing system, whereas
in many cases berries produced and handled under conditions
identical in al] respects except that of being differently sprayed
rotted so badly as to be unmarketable.

DISCUSSION OF SPRAYING EXPERIMENTS

Before drawing definite conclusions from this series of spraying
experiments it may be well to point out certain factors which may
have some bearing upon the results.

In the first place, it is not to be expected that the proportion of
infected berries will be equally and uniformly present throughout
any considerable bog area, as is well illustrated in the extreme case
of Sclerotinia rot. This disease usually appears in isolated spots in a
bog where most of the berries may be infected, while it is entirely
absent over the remainder of the area. A similar condition, though
less marked, undoubtedly holds true of other rots. Local influences
also must play an important part in determining the number of berries
infected, such as depth of vine and elevation of the bog above the
water table. For example, in the McFarlin tests of 1925 (Table 9)
the last two plots recorded in the last two columns were located on

16 BULLETIN 1434, U. S, DEPARTMENT OF AGRICULTURE

low, wet ground on either side of a cross ditch, and the berries from
these two plots developed considerably more rot than the unsprayed
check a short distance away on higher and drier ground. Since the
relative proportion of infection is likely to vary to some extent, it is
not surprising to find that contradictory results were sometimes ob-
tained even on the small, comparatively uniform areas used for the
experimental plots. |

In the second place, it is impossible to establish and maintain
complete coverage of all the fruits ina sprayed area. The quantity of
spray applied per acre, the care with which the spray is applied, and
the depth of vines through which the spray must penetrate in order
to reach the berries are three very important factors in determining
the proportionate number of berries which receive the protective
covering of spray. It is evident that thoroughness of application is
of great importance in obtaining successful results from spraying.

It should also be emphasized that berries in the late-storage tests
were screened early in the season and were then kept boxed until
sampled. The proportion of rot present in such a case is not an
index of the percentage which would be found in commercial berries
in the market at the same time of year, because the latter would
have been screened much later and all early-developed rot removed.

CONCLUSIONS FROM SPRAYING AND STORAGE TESTS

Storage tests conducted over a period of four years lead to the
following conclusions:

Some years an excessive percentage of storage rot develops in most of the
unsprayed cranberries produced in the Pacific coast region.

Each year an excessive percentage of rot develops in certain bogs and
apparently in particular varieties, if uncontrolled.

Two applications of Bordeaux mixture—the first made in the hook stage or
just as the bog begins to bloom, the second in the after-blossom stage, as the
vines go out of bloom—control the development of storage rots satisfactorily, pro-
vided the berries are harvested and handled with sufficient care.

Of the two applications, that at the hook stage is the more essential.

DUSTING EXPERIMENTS

In the 1925 spraying tests a parallel series of plots was treated
with a commercial preparation of lime-copper dust for the purpose of
getting comparative data on spraying and dusting as control methods
for cranberry rots. The dust used in the test contained 25 per cent
by weight of monohydrated copper sulphate and 75 per cent of hydrated
lime. It was applied by means of a hand-blower dust gun fitted with
two nozzles, a method which is not very satisfactory on cranberry
vines, because of the habit of vine growth. At first it was attempted
to apply the dust at a definite rate per acre, but this was abandoned
aiter a few trials, and thereafter an excessive quantity was used to
insure some dust reaching all the vines. Winds, which blow almost
constantly over the bogs in this region, often carried away most of
the dust before it could settle into the vines.

The results of the dusting tests are given in Table 9. It is seen
that the dust failed to give as consistently good control as did the
spray, although in a few instances it proved equal to the Bordeaux
mixture. This inconsistency of results was expected, when so much
difficulty was encountered in the attempt to spread the dust uniformly

CRANBERRY DISEASES ON THE PACIFIC CGAST 7.

over all the vines. Apparently, commercial dusting of cranberries
will not prove satisfactory on the Pacific coast until some superior
method of applying the dust is developed.

TABLE 9.—Percentage of rot developing in storage in cranberries experimentally
sprayed and dusted in 1925

[Berries were screened Oct. 13 and 14 and shipped to Washington, D. C., Oct. 16, arriving Nov. 9]

Sprayed with home- * : Sprayed with com-
| enact Bordeaux Dus with yme- mercial Bordeaux
| mixture | CO RDEL aus mixture
3 |g |o Si SuSels o ow tO le
Variety, bog, and date of a ig \5 31-3 |S,18 8\8,|8\s = 18/8
examination ofstorage ma- 5) ieee! 2/2 2223s ql a1 2 S |=8la
“a1 ol) nl) pb] S | S|o Sie .o 3 ~ Dn TS ness
ceria. Re oe lg elias i wis! Sel 5s as pS! © aS > |PRa sic el B
S(SSSS se a) 8 | S/sSisees a) a) Sige steel a
& [8 S/ 95), 6 & el s(oels=zlal =| a ldaooi2s! &
a |S ul2® 71S an og 2 TEl2 381% B | n Bulag &
ele Ll | Ele) se |salsvieale | Solel. waa | Pz
2le BSs |a| ele |e Bee"| 2/2/28 253 \2
Bi i \j2 |e /OlB io |jeSie |e |/Olm la & a |e
McFarlin, Pilkington bog:! |
SIN Owe: WU steesssssehseedes Selb cal on on Mon Naot nea ni Omm oi ian oO) uO. eGnien Dune Aang 9
Decsn Gest el ake ss oe Ce Oae LO als a ALOR MOM 20 ae US he oem ate
Jes. VRc. VRS Us Hs ey pee Sc aes LOW LE AOS L519) eBON 22 La 12 AS | 23a Se 1G y | S15 890 bes
Bennett, Schimpff bog:?
INO Ved Of seis aes eke 2 4 4 AD tO) 4 Bie e8ch 10 Capea Gt Sel eAeiess 7 6
Dee Gi Pee cee rae AQ 4A 25 N28 2falp Son olen 2oullen| eso oe ei tite Tie Dia eos
AM P4 sete ek Ce ees Bee Cee pe BN ape i fa ea ai ANN SE hs | ek a | te Pape aa Wipe de OS ald so
Searls, Schimpff bog: 8
OV 1 OLe ee Soe ee Cl Gehl Leafy = Bh bee BS agile rested bea kTL arse N ios Gate lay dl 2 7/18 Ve 8
DeecG ists Geiger es yey DLP LOM Sy ll We) 16 tO ely 276 al 2e) 16 208 De 10293) A6a 25
ERIN AA Ys ae ee a eae 22 | 15 | 10 | 18 | 19) 18 | 18 | 16} 10 | 15 | 24 | 82 | 15 | 18 | 14119 | 25

1 First application June 5 at hook stage; Bordeaux mixture, 4-4-50, with 2-50 soap in homemade, no
additional spreader in commercial. Second application July 13, after blossom. Third application Aug.
7; berries one-half to three-fourths grown. Hand picked Sept. 17 to 21.

2 First application June 15 at hook stage; sprays same asin 1. Second application July 21, after blos-
som. Third application Aug. 8; berries one-half to three-fourths grown. Scooped Oct. 6.

3 Sprayed asin 2. Scooped Sept. 22 and 23.

COLD-STORAGE EXPERIMENTS

The question has been raised among the growers as to whether
cold storage of the fruit might not be substituted for spraying in the
control of storage rots. The plan was proposed on the following
grounds: No decay is found when cranberries are picked. If the
entire crop is screened and shipped immediately, the grower will
suffer no warehouse loss in the first place. Pacific coast berries at
present are consumed in an area lying wholly within a radius of three
or four days’ haul from the bogs, and very little rot should be expected
to develop in a shipment of such short duration so early in the season.
Consequently the berries would reach the distributing markets in per-
fect condition very soon after being harvested. They could be imme-
diately placed in cold storage and held until a market demand arose
and would then be consumed before any rots developed, if such stor-
age was found to be satisfactory. Furthermore, it might be possible
to prolong the marketing season of cranberries by holding them in
cold storage for later distribution. |

The following data were obtained on cold storage: In 1922 a box
of Howes berries from the Wills bog at Long Beach, Wash., was ship-
ped to Washington, D. C. On arrival two samples of sound berries,
consisting of about 1 peck each, were sorted out and put in ventilated
boxes, one of which was placed in the cold-storage plant at the Arling-

18 BULLETIN 1434, U. S: DEPARTMENT OF AGRICULTURE

ton Experiment Farm, Rosslyn, Va., at a uniform temperature of 32°
F’., while the other was kept in a greenhouse as a check. The berries
were held from November 13, 1922, to January 20, 1923, when the
percentage of rot was determined. The berries kept in cold storage
showed 3 per cent and those in the greenhouse 10 per cent of rot.
The berries used in this test, as the check showed, were of good keep-
ing quality.

A box of McFarlin cranberries grown at Long Beach, Wash., and

laced in a commercial cold-storage house in Los Angeles, Calif., by

.S. Gane in the fall of 1921 was examined by the writer in Novem-
ber, 1922. It was not learned at what temperature this house was
kept, and nothing is known of the condition of the berries when
placed in storage. The berries were practically 100 per cent rotted
when examined and were overgrown with molds, Penicillium and
Fusicoccum being very much in evidence.

In 1923 cold storage was tried experimentally on a scale large
enough to give an indication of what might be expected from it com-
mercially. The end-rot fungus is known to grow slightly even at
32° F., so the temperature would have to be kept low to prevent the
development of this organism. On the other hand, it would be diffi-
cult to find commercial storehouses in which the temperature is held
consistently at or near 32° F. Bearing these two facts in mind, the
cold-storage plant selected as furnishing the most favorable temper-
ature conditions among the several which were kindly placed at the
disposal of the writer was the meat storage house of Swift & Co., in
Astoria, Oreg. The temperature in this warehouse is held at an
average of 32° to 34° F.%

Tap LE 10.—Percentage of rot developing in cranberries in cold-storage test in 1923

[All samples were screened Oct.26 to 31. Check lots were kept in unheated warehouse at Clatsop,
Oreg., and other lots placed in cold storage Noy. 1]

MeFarlin, MeFarlin, Bennett, ape Cod Centennial,
Bloomer bog, Morse bog, | Pilkington bog, PUREE Pugh bog,
not sprayed sprayed sprayed speive i sprayed
Date examined
Cold Cold _| Cold | Cold Cold
storage Check storage Check storage Check storage Check storage Check

January 14, 1924____. 16 25 4 7 8 18 13 24 16 21
ANT e26; O24 wees ae 67 fSileeetes Lo See woe So leeeseaee 30 58 45 64
August 8, 1924___--_. STA EERE as. 31 64 62 ADAP tse 2h) BERR Le ee See ee

For these tests, McFarlin cranberries were selected from sprayed
and unsprayed bogs and Bennett Jumbo, Cape Cod Beauty, and
Centennial from sprayed bogs, the latter three being considered
comparatively poor keeping varieties. Two standard shipping boxes
(in the case of Bennett and unsprayed McFarlin three boxes) of each
were kept in cold storage, while an equal number of boxes of each
were held as checks in a cranbeiry warehouse at Clatsop, Oreg. The
berries were screened and boxed by the growers October 26 to 31 and
were placed in cold storage November 1. The condition of these
beriies when removed at successive intervals is shown in Table 10.

3 The variations (dsily maximum and minimum) as determined by a thermograph record for one week
(Nov. 14-20) were as folluws: 64-27, 33-24, 36-30, 35-31, 34-30, 32-29, 38-34° Ff. The average daily temper-
ature for this particuler week was 32.2° F. The extreme daily averages were 28.5° and 36° F., respec-
tively, and the extreme temperatures 24° and 38° F.

CRANBERRY DISEASES ON THE PACIFIC COAST 19

On January 14,1924, when the first lot was taken out of storage, all
the samples were sound enough to be sold without remilling, although
Cape Cod Beauty, Centennial, and unsprayed McFarlin were begin-
ning to decay rather badly. On the other hand, the checks were
not in decidedly poorer condition, showing only from 3 per cent to 11
per cent more rot than the cold-storage berries. ‘Three months later
none of the lots withdrawn were salable, while the margin between
cold-storage samples and their checks varied from 11 per cent in the
unsprayed McFarlin to 28 per cent in the Cape Cod Beauty. At
the end of nine months the cold-storage sample of sprayed McFar-
lin was still in fair condition, as were the check berries of this lot,
considering the length of time they had been held. The check lot of
Bennett was almost as good, but the cold-storage lot was not much
better than its check.

Under the temperature conditions prevailing in the test, rot devel-
oped so badly even in two or three months that poor-keeping berries
would require remilline before being marketed. To be effective the
temperature would have to be kept lower than was the case here, but
whether or not a lower temperature would prove entirely satisfactory
remains to be determined.

RELATION OF WEATHER TO KEEPING QUALITY

In the foregoing discussion of field diseases emphasis is frequently
placed upon the relation of favorable weather conditions to the prey-
alence of the disease under consideration. Later it was pointed out
that infection by storage-rot fungi takes place in the field. It is
natural to infer, then, that the degree of infection in the latter case is
likewise dependent to some degree upon the weather and that cran-
berries will consequently develop more storage rot in some seasons
than in others. That this is actually the case has been abundantly
proved in the older cranberry areas, and it is becoming more and
more apparent in the Pacific coast region as the production there in-
creases. ‘The problem of evaluating all the various factors controlling
storage-rot infection isso complicated that many years of careful work
will be required before our knowledge of these relations becomes very
exact (11,12). On one phase of the problem, however, there are defi-
nite and convincing data, namely, the effect of storing berries wet
upon the subsequent development of rot.

The importance of this relation in the Pacific coast region is
apparent when the seasonal nature of the climate is considered.
During the summer months there is very little rainfall, while the
autumns and winters arerainy. Fall rains sometimes begin before
cranberry harvesting is finished, and it appears to be in such years
that the greatest trouble with rots is encountered. To give a clearer
picture of the relation of picking to rainfall, notes on the weather
prevailing in September of the last four seasons and in October of
the last three seasons are presented in Table 11. ‘‘ Rainy” days as
recorded include those in which rain fell all or part of the day, the
vines and berries remaining wet in the latter case.

20 BULLETIN 1434, U. S. DEPARTMENT OF AGRICULTURE

TaBLE 11.—Weather conditions on cranberry bogs in Claisop County, Oreg., dur-
ing the months of September and October in the years shown

September October
Day of |
month
1$221 1923 1924 1925 1923 1924 1925
|

a = eases Rains Partly cloudy] Clear _______- Gleare2 Clear 2 sceb eee Raina Clear
ps1 | SOREN ARE NC Esty ey rn fete aa Gowseuan afi ner(G Vg} ilies Ak loner pasa Go Nese melvalovacatie de Do.
=) lien (aa ie ia MLA ek Clears weeks Partly cloudy | .___- COU) RDN east hawee ei Bee L HUM Ve Vey make es Do.
APs TA Rein sw ee Cowes saeee Cloudy 222 Cloudy ey Partly cloudy_| Clear __..- Do.
13x al leh ial om Sons ele Lanna he doe es @lear isa! Cloudy, wet)=|"Rainl2e ies BRING ayia? Si cee i Do:
Gest IR jo eee. Gio; tiene Vapereayy Seu a ee Goes Clear sts do 7 Cloudy-
pom eu VI ia es an COG) ee a fae dose tena a doe tent eles do eh: | Cloudy -_-_!
See Pee Cloudy ______ Partly cloudy} Cloudy _____- Rains sare VWRaime sine
CG SNe fe TOR ng RUSS (6 Koepie tah Gileayr) ecules Wa) pees Goje a Cleaner. ec i Oe el

HQ) eesti is avn ome Leven Ao COS ptt MORES dopesene Clear aey Cloudy 22230} Clear 123)

TET Sse PR SUA ED (Gos haan) ise dowiaius Cloudy _22-_- Clear 2224222 do wee |

19), Ae ANG OA cet NRE SE Cosa OE geal aN Clear aaa ed Ortaca (Etqinae enna

UE He i) ie etre Cleans ues Cloudy ee ee a pees Goya: Partly cloudy 2)2-do2 22 |

AS eae BHO Srits Maye ny) eae ro Lays uy apt Partly cloudy | -__-- owe ae Cloudy; then) 22 do 222234 |

cloudy. rain.

1 lis Re Cloudy ___| Partly cloudy} Cloudy ______ Rain) eens Rai aes a See a Koyuae Nea ae

LCG RAI (a CRA on Clea aera lh does Clear eee Suwa COR Cleareaes

TL 7p Hea ap sea Partly cloudy |___-- GoewssOen | ele a Co Ko fees eh GOSS P Ne cea OUEAE ee

PS oli il MIST Yaseen IVES yes ain eee 8 leeyn aye ee Cledrj= 222 9 ues ISAK 9 Voyeate ery

OR pieeleo Koel ieBEVeninaiaus weet anes Cleanu wigan! CHO Tee aes Naa en Gori wo ed

OY) ae A RS a ea ade ed lear) 22eike C@loudy2 a eae ae Ne dofAsa wes | Partly

cloudy

OO as ee TEs bay ey Se doe etaes 1 SU oS Ae SEN Ua dojo emus Reine ee ae Raia ee |

DD eae A| sie 2 aI Ae co Vos aS ee a Ee a ores atl ae Go eal 2 etwilee ew Oi ead Cieareeee |

G3 Sie [| a ip oT ONE Bantly rainy, 4|seee GO eye an ease 010) separ I@LG AT wee ome suerte teenie |

Yes CSc | eC a made aes Ba Goreeeet Cloudyisee ae Goi te ween Jabk dopetak la

D5 ek eh Rains es @leariceens in: Partly cloudy |.---- Gopte See aiaee ew do burmese, CWEdOQVEL Uae

D6 aa aro Vos sheleeae ee Goer Clear 22a @Wlearis27 sb) eae Goes weaves HER OME

PH (at es SEA OVIR AAAs Gobet ek okey ay-AtS OH) He ee pe Co) 6D ale Dba Co Koy eal ss hE LEMOS EEE!

DS ara Clear te we a0 es dope eee (6 Koy reset ut 1 Bc faNy jes URL A ANTES Sip Gop PAE G Ko) eR |

Zor esa Matis skal oe ee don sae Cloudy ee aie dora Partly cloudy-_|_--do -_.---

Ci MR LY SD Pa ld Go} Sawin. Riainmenie Cleark . as eee IWNIStiy; tie ee Cloudy _--|

Bay ss NR SS Aa PFA i ss ee A a a ud @leagr onal ewer Jey es

1 When condition of weather is not shown the bogs were dry.

The harvesting of early varieties usually begins soon after Septem-
ber 1, but picking does not become general before the 15th or some-
times still later. As a rule the harvest season extends well into
October. The year 1924 furnished an illustration of a rainy pick-
ing season. Berries were late maturing, picking being started on a
large scale after September 20. Reference to Table 11 shows that
on the average not more than two days a week were classed as dry
after this date; that is, a considerable portion of the crop had to be
picked in the rain, and it was very difficult to dry the berries before
storing them in the warehouse. In addition, from 1 to 10 per cent
of the unharvested berries were frozen on October 10. As a result
of these two factors the 1924 crop kept poorly. Berries picked before
the rains kept unusually well, this being especially noticeable with
the Searls variety, which often rots badly, and with Bennett when
picked early. Table 8 shows that the Bennett in the experimentally
sprayed plots also kept satisfactorily, although they were picked
after the rains started. The entire bog on which these plots were
located was very carefully sprayed twice with Bordeaux mixture,
yet some shipments of this variety from the same bog rotted badly,
the only difference in handling being that the experimental plots.
were picked on one of the few dry days while some of the crop had

to be stored wet. Storing berries wet invariably causes a decided.

increase in the development of rot.

|

CRANBERRY DISEASES ON THE PACIFIC COAST

With the danger of early fall rains always present, it is essential
for the harvesting period to be reduced to a minimum in the Pacific
coast region. Each grower must learn by close observation how early
his crop may be picked and still color up sufficiently by marketing
time. Rapidity of harvesting, once the berries are colored well
enough to pick, can not be too strongly emphasized.

Care should be exercised to see that all berries stacked in the
warehouse are thoroughly dry. Spreading the berries thinly in crates
in moving air will often accomplish this result, but eventually some
of the larger bog owners will probably find it profitable to install
some type of drying machine similar to those in use on a few of the
eastern cranberry bogs. Though it is far preferable to pick only dry
berries, the writer recognizes that this is often impossible; hence the
emphasis placed upon the importance of thoroughly drying before
storing.

E CULTURE WORK WITHV CRANBERRY ROT FUNGI
MATURE BERRIES

Most of the fungi which cause rot in mature cranberries produce
symptoms so nearly identical that the causal organism can be deter-
mined with certainty only by means of cultures from the decayed
berries. Therefore nearly one thousand cultures were made each year,
to obtain an idea of the fungi responsible for the decay. The material
for these cultures was usually taken from storage experiments, but the
latter represented the most important varieties and a sufficient
number of bogs to give a fair indication of the relative prevalence of
the different fungi during the year. Cultures were made each time
storage lots were examined, in order to include both early and late
decay-producing fungi (5). A more comprehensive study of the
succession of rots which develop in storage is planned for the 1926
season, including berries from each of the important commercial areas.

Berries were surface sterilized five minutes in a 1-to-1,000 solution
of mercuric chloride in 70 per cent alcohol, and bits of the decayed
pulp were transplanted into test tubes of corn-meal agar. A single
culture was made from each berry. Tables 12 to 16 show the fungi
that developed in these cultures year by year and Table 17 gives a
summary of all cultures made in the series of years.

TaBLE 12.—Fungi developing in cultures made from rotted cranberries in fall and
winter of 1922-23

Wills |Washing-
Gibbs Oregon bog, ton
Fungus bog, experi- Long experi- Total

Hauser, | mental Beach mental

Oreg berries Wash berries
Acanthorhyncusrvaccimiipier sam Wen ss eau ON en oe Pa Meta as Aa Aa 4 6
BO tivity yee era he DMN OM GEN COE sia Ae a 3 eT Pe Reale, 14
Weulhosporaylumatae ena meee Wim eanae [EVI ane BION a eg lar AE MO Ne 10
MUSICOCCUMMEp UtKehaCleMS ja mes ee dian jie eae ea een 28 248 80 47 403
Gilomerella nalomacmlans vaccines oo anemone N | puis) UNE Zhi as eae IS aaa 2
Girton ardiatvaceimiiiee yeah Tee Re Genny The eam Gy ee eae 4 10
Ome TT cama SW se OEE NN pa AUN Niel yA NE VL UR BUT 14 26 1 41
JeESuA ovAAeY IO oso BYoovaNT Le (RES eA A RU ean 1
IBS ZIZE Nay ET ee ea GS ET Lek Um) OCR EEN aon Ne Pep ree DN Lise Ny atin NU 1
OM OP SIS: ev aakeeae sue ONL LT UN SH iLay NN Ve 12 Pol Bee NS i tical 2 57
SPOLOMEeM aoxycOcel ma. Vac 2 RE Ye 4 AGM Cue a 14 64
SS Eerie wei ee SU NOT AUR AM al EE 8 112 101 20 241
INGO GHG Ora bichie el erro nen CR Nae a ls reo ee 5 45 28 14 | 92
Motalonitimibersofeultunes wee ee 56 534 246 106 942

22

BULLETIN 1434, U. S. DEPARTMENT OF AGRICULTURE

TABLE 13.—Fungi developing in cultures made from rotted cranberries in fall and

Fungus

Acanthorhyncus vaccinii
Botrytis sp
Ceuthospora lunata

Fusicoccum putrefaciens_____________

Guignardia vaccinii
Penicillium

Pestalozzia guepini vaccinii

Phomopsis sp
Pleospora sp
Sporonema oxycocci
Sterile

Total number of cultures______ |

ep.---—--~- -------- --- - eee

winter of 1928-24
Dellin-| Hiesel-) | Bloom-| Hill | pooig | Pugh
Ber bog.) hog bog, |er bog, |_ bog, bog bog,
Ber ian: Searls |MeFar-| McFar-| o. yj, | Pacific | Total
nett ee ee eret lin va-| lin va- ae Beauty
variety variety y riety | riety y variety
pas eeepc PA TEAS A War Pt eater ea DBE AMgY ob a Mi eee 4 6
Eve EM OC ae 2 a Wa at OR RS a | 1 2
py ins S| 9 Ce ca oh 8 DAN Salis ane 2 Uh ad Sc ee 10
69 124 104 60 30 90 4) 518
papaya os a es ana DU Sere eg ate AM MAL EO PS aa UN 1
1 2 Oy | Bea a cae 1 3 5 15
LE et Se ear | SS cah eh et cA a a a ch ya | Bs ee 5.
18 3 22 9 6 23 by 86
AN) NASSP a Boel BD sty Vice atid Nivel ease ea Pi era ees 2
aE eae eae 8 4 tN] ha ea 13
7 12 8 12 9 10 27 85.
| 5 2 2 LO meow 6 18 43
100 150 150 100 50 135 101 786.

TaBLE 14.—Fungi developing in cultures made from rotted cranberries in fall and
winter of 1924-25

Schimpff
og,
Fungus Searls
variety
BOUL CISHSDsh.) Sa 14
Ceuthospora lunata_-___- 4
Fusicoccum putrefaciens- 122
Giloeosporium' spy 2222 An Ean
Penicilliumesp ss. 22 Lee 2
Pestalozzia guepini vac-

COND COU pau! Uo a TL OAT Se ete RM
EATOMLODSISS se nee ese
VIZ OP USES eee eae babe ele oe he
Sporonema oxycocci.----|----------
Sterile cy 23a ee eed 15
Not identified S222 2e es 4

Total number of
culties 222s ara 50

Schimpff

1 Two fungi in one culture.

West | West ne Focle Dellin- | Taylor

bog, | bog, Rterar! en- [Ser bog,| bog, | motal

Howes | Searls |, ya-| nett | rotten | rotten

variety | variety riety | variety pile pile

I all HT i YU ad la ahead PU Tg 2 8

pice PS ao 114 1 1 1]1 1 36
33 166 172 43 138 123 340

IPG UOLAELsg) |e Mo Dat INS NB a I or A 4 4

BE ET (pe See en 1 1 142 113 30

i ee al RN DE teats eA a a 4 5
1 2 6 1 4 2 17

MA eno GEL) EOS chmod |, AUS Re eae A OAC Peas Nt 2

papa ele tae | Aap GL) | ue Rea 15 118 24
16 20 14 1 9 19 95

Layo AA da 2 3 20 19 49
50 100 100 50 100 100 600

TaBLE 15.—Fungi developing in cultures from cranberries rotten at harvest time

|

Poole and
Dellinger
: bogs, :
Dellinger | Poole bog, Sean Fiesel-
bog, Ben-'Searls and Bennett man bog, Total
Fungus nett Bennett @entent ’} Bennett
variety | varieties nial, and variety
other
varieties
1 BoB) ENYA EBA SPR © ese Murata Ube > UIEY TSOP ee NU oy UR HS ML NU AN SI Ie NN) RA ONG aD apa wet ft ie Oe 1
NUSICOCCIIIM PUTKELA Clem G saws ees AE eee ae DU Me RES Ly EE Me Be 3
[PN OTO PSISSS yes was A) VO ee PR ale 70 53 24 25 172
DD OV OWS TINA» OK, CO CON a wane sea ees LIE Dae Nala is ee ee taut Pedra A ar dg Pa iL OI ee aaa 1
GOT hee ee aa ON a Le ee SO an I ne et i She aes i ta 10
AdoHA sal bhoal oxery Ope rcbDhiohEh LA eee 72 60 30 25 187

CRANBERRY DISEASES ON THE PACIFIC COAST

23

TABLE 16.—Fungi developing in cultures made from rotted cranberries in fall and
winter of 1925-26

Fungus

TE YO HEAR einsy C)2 COU ees es Ae Nas BAU EY Wee ie a as Ae ee ee eS |
Ceuthospora lunata
Fusicoccum putrefaciens
Penicillium sp
I; HOMOPSISiSP esas seen ee ee Sees eee ee ee Nee bo eee oe oo
Sporenema oxycocci
Sporonema pulvinatum
Sterile

1 Two fungi in one culture.

[
Total
Schimpff | Schimpff | Dellinger} number
bog, bog, Ben-| _ bog, of times
Searls (nett vari-| McFarlin | each fun-
variety | ety variety | gusoc-
| | curred
13 | 1 | 3 | 7
ia 5 | 10 | 15
1140 1202 | 1429 | 471
154 10 137 101
113 15 | 10 | 28
4 1 5 10
See a 1 ball as ree ats Be 1
24 | 6 15} 45
57 | 15 | 44 | 116
266 237 239 742
|

TaBLe 17.—Complete summary of fungi developing in cultures made from rotted
cranberries on the Pacific coast in years shown

|
|

Fungus | 1922 1923

A canthorhyncus vaccine 2. 2s. 6 6
ES OG ISVGISINS [see res re ee er ns 14 2
Ceuthcsporaglunatasess. te eee 10 10
Fusicoccum putrefaciens._..-__----22___=- 403 518
GTOCOSDOTITTIYS Pea eeu Mi pe ENS Scie TR oa re
Glomerella rufomaculans vaccinii_-_-.____ i ease Se
Ginrenardiaivaccimils ses. tae 10 1
IREnienliqim es pss aes oe eee BS eee 41 15
Pestalozzia guepini vaccinii_..___________ it 5
TO ZAZO TA yy sb EN Tie ane ek es eee big oeeshen? 2) Bete
IBWOMOPSIS ZS see ee ee sae iy eta a es BT, 156
IPl€OSPOta-SPsss sos Se 2
AEVAZ OP IISES [see eta es ik oh eR ee ee hd See eae RE ANE Se ole
Sporonemay omycocci ses 22 sre Ts 64 13
SPoronemarspMlvin abides aw ee oe es oi aE es ea Pos Pe a
Sterile orgs Cen ksa epee Seat ga ae 241 85
IN GEGEN tied et. Bes eae: eee Ee Do ae 92 45

Total number of cultures__________- 919 | 856

1924

1925

Total
number |
of times
each fun-)
gus oc-

curred

3,232

Percent-
age of
total cul-
tures

Kind rot, caused by Fusicoccum putrefaciens Shear, was found to
be by far the most important rot in the Pacific coast region.
fungus appeared in more than 60 per cent of the total cultures which
developed any fungus growth. The remaining species of fungi varied

somewhat in abundance from season to season.

This

The five species

occurring most often were, in the order of their importance, F'usicoc-
cum putrefaciens (end rot), Phomopsis sp., Penicillium sp. (soft rot),
Sporonema oxycoccr (ripe rot), and Ceuthospora lunata (black rot).
The total list, however, includes nearly all of the fungi which are
known to rot cranberries in eastern cranberry districts, as well as a
Tew others of minor importance, such as Botrytis and Pleospora, which
have not been found in the eastern sections.
striking feature disclosed by these cultures is the almost total absence

Perhaps the most

24. BULLETIN 1434, U. S. DEPARTMENT OF AGRICULTURE

of the early-rot and bitter-rot organisms (Guignardia vaccinii and
Glomerella cingulata vaccinia, respectively), one or both of which are
generally among the five most important fungi found in comparable
studies of eastern cranberries.

Two rots are found in storage which may be determined by symp-
toms alone, hard rot (cotton ball) and black rot (caused by Ceutho-
spora lunata Shear). Hard rot has been described above. Black-rot
berries are, as the name implies, black or bluish black in color and
are usually rather firm in texture, whereas the majority of other rots
are of the soft or watery type. The proportion of black rot is some-
what higher than that indicated in the tables, because berries obvi-
ously rotted by this organism were not often cultured.

Proportionately, all varieties appear to be affected about equally
by the different fungi, with the exception of Bennett, which has a
higher percentage of end rot as a rule, and Searls, which often shows
more black rot and Phomopsis than the average. Since the storage
experiments showed that unsprayed Bennett and Searls berries inva-
riably rotted worse than all other varieties tested, it is logical to
conclude that these two varieties are more susceptible to these fungi.
Sporonema was rarely found on any variety except McFarlin.

Table 15 gives the results of cultures made from berries that
rotted early—that is, just preceding or following harvest. It was
previously pointed out that this early-developing rot is largely due
to Phomopsis.

TABLE 18.—Fungi developing in cultures from green Howes cranberries from West
bog, West, Oreg., in 1923

June 26, | July 3, | July 11, | July 16,
flowers | bloom berries | berries

g. Aug. 22
berries | aug.9, | berries’

open or gone, ze to nearly July 25 aol berries begin-
just berries | 1% inch half- fount large ning to
Fungus fallen | wellset |diameter| grown eae ripen
wiBis:iw/B/s|w/B/S |w|B| s|wiB | s|w|B|s|w)/B/s|w/B|s
| |
—|—|— = | fe eR | | | eee
Acauthorhyncus vac- |
CLT ee oe es [sel sears ee wei] hse ah 2 eer Rell pd enone | tar =r (enol) Kea eam Feemeel (v pmCPCeY Fey ee] YRS MSP Pe PONE aS
Botrytis spans oes De UR 1 Nee i a) 8 aN i Re el) BISON Ae eo We nel a ee yy Ree
WeuEWospora lara beats Ss see ea ee Ee Deis itt eee ste aT Lo aD |e ie | PTS |e
Cladosporium sp.---- Sf pal ue ed i ef SSN (a ea fe ea aU al RN | ST Ua as Hae TD
Husarium) spss 222 22. 55 LAN EM NSC PSS Hee i 20 ATT eA ah A TEs yg ee aN ge et eg Tg eS a eae
Fusicoccum _ putre- |
HAGCIONIGN = mere on LA he Nn TERPS PS ee ee ag We 4 ei tl mf Dg cya 19 Fac sees ACN tea Ry ee rai 45 | 4] 1
Guignardia vaccinii__|___ BORA ES i SN BAER CSTE 7s CASE AR eS Nf DT FR eh HAD
Renicillinm) spe #s|_2 2 WU aR ALE fle Slee in. anak ale QR lie ae Dae Han) PEARS pewter gee eget
Phomopsis sp._--____|__-_ Mp Wea as a While Fie | pean YR | Ls helo A i Ry Mange IL Sale Y
Pleospora sp.----.---|__- E12 EIRP eae eR i a SS sig ae ee | |g 1d LE Ee EEE
Siomlew Oo hepsi, 2 ae OCHS RO a ra EM, oo Pree 7/8/9/5/9/3)1)] 8
Notidentified_.______ OP ML PAP EZ ods DIZ nial Aet ht mn est ail eae B yy Ntsedi il iy em ean), oma Ld Sa ie meee
Total number | ; |
of cultures___|10 |10 |/10 |10 |10 10 10 |10 |10 {10 |10 |10 |10 ro 10 |10 |10 {10 |10 |10 |10 |410) 10) 10
| |

1 'W indicates that the whole berry was used for culture.

? B indicaies that blossom-end half of berry was used for culture.

°$ indicates that stem-end half of berry was used for culture.

4’Two fungi in one culture.

5 Many unidentified fungi were contaminations, especially frequent in the earlier cultures made before
a culture chamber was available.

CRANBERRY DISEASES ON THE PACIFIC COAST

25

TABLE 19.—Fungi developing in cultures from green Searls cranberries from ,West
bog, West, Oreg., in 1924

Fungus

Alternaria sp
Botrytis sp
Cladosporium sp---
Fusicoccum putre-

faciens
Guignardia vaccinii-_
Penicillium sp
Phomopsis sp
Pleospora sp
Sclerotinia oxycocci-
Sterile

aa wee ee eee

Total number
of cultures__
|

= |lpo | | |
Bo (eB | pom” | July 24, |
5 aie nearl some | July 31, Aug. 25
a ie aa bloom, berries | Aug. 9, He eien: Sept. 8,
oaijesg | & ae some half | berries | Aug. 16 ) oi ning| berries
Bi (ok pa , berries |grownon| large g1nDINg ripening
aa |E | berries half average to ripen |
Sg lgo2| fairly
St) eos) large ere
OF ISO
hp i |
be |e | | | ] ]
= Bw) W1/B 2 S34) W) B S|W! BI! S|W).B!|S/|w] B| S|wi B!|S!|wi Bis
aia) ad, Be ale ees Ed gyi aie alee Ie
eee, bet Nee a Na SAN UU Bed We PNY SADA a ae 1) Kal) Ul | Dl af
eB Ey eee | ct abs | ens A DT A | La | vs a nt Pee i ee | | Ve af
|
bad wit ADT NG TPS RAE MUL Se Silay ta Let eae SL NEE SN By AM A Bee 9) ENT
ee eS TL Alpeeea: tal te ATR Tae AIS Yee pe Ps Dge E Ae BN el ies 21 a 3
ae a OeieeA| MN epee Sat Nhsa UN LS ed LU Uy Liye ee Waid a pe at a i Sw Ne one Leta el VTE I
Baers NL Eig earn Awe (A Se ema tp Peas Ree eM) ner Ect P8 De El ea (Pn cae ee a ee
FPS Raat Crepe Teed Woe a Sa eee Ag P31
mee Lon HU ges 8 feet | pes | PAPAL JUL [pe | PAMPLGLAH ca cee GP aL etal| Pee ao CA UU a
30 SSG eal Sete OM Z On Me AOM A OL KA CAC Gi ae vee 7 ta 6
Ape Ste, TEN BSA PANDA AICS: May) Asay HRS Ei ec A 1 j---) 1 |---| 8} 1) 5) 4/1) 2 |---/--
30 30 '10 /10 |10 |10 |10 j10 10 {10 /10 |10 /10 uo 10 |10 |10 {10 |10 }10 ue 10 |10
[oar

1 W indicates that whole berry was used for culture.
2 B indicates that blossom-end half of berry was used for culture.
3S indicates that stem-end half of berry was used for culture.
4 Two fungi in one culture.

TABLE 20.—Fungi developing in cultures from green Bennett Jumbo cranberries
from Gratke bog, Clatsop, Oreg., in 1925

Fungus

Botrytis sp
Cladosporium sp-_-
Ceuthospora lu-

Fusicoccum pu-
trefaciens _______
Guignardia -vac-
cinii
Gloeosporium sp_-
Lophodermium
oxycoccus (Fr.)-
Penicillium sp--_-
Phomopsis sp
Pleospora sp
Sterile

Total num-
ber of cul-

June 27, midbloom,

on

some buds

| July 7

50

50

1 W indicates that whole berry was used for culture.
* B indicates that blossom-end half of berry was used for culture,
3 § indicates that stem-end half of berry was used for culture.
4 Two fungi in one culture.

ey atl

Ba 3

2S n

Sy 8 os

B26 BE

S & bb 2h

BO oe

See | 5 * By ROUTES (ities

ee ie et is 2 rot

= 5 = < < D D

| | | ie eal
W1B2S3/W/|B|/S/W|B/S|WI|B|S/WIB|S|W/B/S/|WI/BIS
Anis Model aes Dike (eee Me gen Roe SDA Lc eM bale I Ip ae dh
Dues De Ay 0 aa i Ae Fe Badge | ease | ee |
Se Pa val Ma bik iP Ll eid a el ag et a FU jks
Le AN I ea Wa Ce) a 1 26 8 Ve 3.7 2 Gus onmt
os SI eed a al Ra MeN a A lea i Pe hl 12.15
Ecol Ha eS at FL osama aoa A US iss (a a Peo If oN
4 EP Se i PY
Fel isa hepa | CO etalbayh iil esd el eth pe pe el NP SIS
19 |14 115 | 6 | 3 [15 [12 [12 [15 | 5 | 1 [13 | 7 14/8/4113}9|6/9
LS ENE eee ANM Ty eliare | del ten Sle) | Tal 5 Sele On ea Imes
20 |15 |15 Ey 15 |15 |20 |15 |15 20 |15 |15 |20 |15 |15 |20, [15 |15 |20 |15 |15
| | | |

26 BULLETIN 1434, U. S. DEPARTMENT OF AGRICULTURE

GREEN BERRIES

The Office of Fruit Diseases of the Bureau of Plant Industry has
for several years been making cultures from green cranberries at
intervals during the growing season in an effort to clear up the prob-
lem of infection by storage-rot fungi (13). As part of this program
similar series of cultures were made in the Pacific coast region.
Beginning about blooming time, green berries were collected at weekly
intervals, surface sterilized for five minutes in a 1-to-1,000 solution
of mercuric chloride in 70 per cent alcohol, and planted in test tubes
of corn-meal agar. As soon as the berries became large enough to
be conveniently cut in half, cultures were made from blossom and
stem ends as well as from entire berries. The results of these cul-
tures are given in Tables 18, 19, and 20.

The results of these cultures agreed with the results obtained in
eastern cranberry districts, namely, that storage fungi infect berries
in the field rather early in the season. Usually the cultures made
just after blossoming developed almost as high a percentage of stor-
age-rot fungi as those made later in the season. The high percent-
age of sterile cultures from the stem-end half of the berry indicates
that infection takes place largely at the blossom end. Guignardia
alone occurred more frequently in stem-end cultures than in those from
the blossom end. Fusicoccum appeared much more frequently than
any other fungus. Botrytis ranked next in importance, and Pleo-
spora, rarely found in mature-berry cultures, was sometimes common
in the earlier part of the season. In all, 1,000 cultures were made
from half and whole berries, and storage-rot fungi appeared in 222
of these.

It is perhaps needless to point out the relation between these
green-berry culture results and the results obtained in the spraying
experiments. In the latter it was found that hook-stage and after-
blossom applications of Bordeaux mixture invariably improved the
keeping quality of the berries; the former showed that storage-rot in-
fection had largely occurred some time during or soon after bloom.

SUMMARY

Four years’ study of cranberry-disease problems in the Pacific
coast region led to certain conclusions which are summarized below:

Six diseases of vines and leaves are described and control measures
for the more important of these are suggested.

Field rots of berries are of comparatively little economic importance.
Hard rot, caused by Sclerotinia oxycocct Wor., sometimes causes loss
in local areas. The life history of the fungus causing this disease 1s
presented and control measures are suggested.

Storage rots, caused by various fungi, are a very serious cause of
loss, both in quantities of berries and in effect on the good will of
the trade.

A series of spraying experiments followed by storage tests demon-
strated that two applications of Bordeaux mixture, the first just
before blossom and the second immediately following blossom, will
control the development of storage rots satisfactorily.

Dusting with a lime-copper mixture, in less extensive experiments,
failed to give as consistently good control of storage rots as spraying.

CRANBERRY DISEASES ON THE PACIFIC COAST 27

Cold storage at an average temperature of 32° to 34° F. failed to
prevent the development of rots, particularly over a period of several
months.

Wet weather at picking time, and especially storing berries while
still wet, increased the percentage of storage rot.

In more than 3,200 cultures from individual rotted cranberries,
end rot, caused by Fusicoccum putrefaciens Shear, was found to be
decidedly the most important rot. Practically all fungi known to
rot cranberries elsewhere were found in cultures made from Pacific
coast berries.

At intervals during the growing season 1,000 cultures were made
from green berries. Infection by storage-rotting fungi was found to
take place chiefly during or immediately following the blossoming
Cee Infection usually occurred on the blossom-end half of the

erry. :

LITERATURE CITED

(1) FRANKLIN, H. J.
1916. REPORT OF CRANBERRY SUBSTATION FOR 1915. Mass. Agr. Exp.
Sta. Bul. 168, 48 p.

(2) 1919. SEVENTH REPORT OF THE CRANBERRY SUBSTATION. Mass. Agr.
Exp. Sta. Bul. 192 : 105-141.

(3) Hosson, A., and CHANEY, J. B.
1923. SALES METHODS AND POLICIES OF A GROWERS’ NATIONAL MARKET-
ING AGENCY. U.S. Dept. Agr. Bul. 1109, 36 p., illus.

(4) Puank, H. K.
1922. THE BLACKHEAD FIREWORM OF CRANBERRY ON THE PACIFIC COAST.
U.S. Dept. Agr. Bul. 1032, 46 p., illus.

(5) Rupowupg, B. A., and FRANKLIN, H. J.
1920. ruNer stupiges. Mass. Agr. Exp. Sta. Bul. 198 : 88-92.

(6) SHEAR, C. L.
1907. CRANBERRY DISEASES. U.S. Dept. Agr. Bur. Plant. Ind. Bul. 110;
64 p., illus.

(7) 1916. FALSE BLOSSOM OF THE CULTIVATED CRANBERRY. U.S. Dept. Agr.
Bul. 444, 8 p., illus.

(8) 1929. CRANBERRY DISEASES AND THEIR CONTROL. U.S. Dept. Agr.,
Farmers’ Bul. 1081, 22 p., illus.

STEVENS, N. E., and Rupowpu, B. A.

1917. OBSERVATIONS ON THE SPOILAGE OF CRANBERRIES DUE TO LACK
OF PROPER VENTILATION. Mass. Agr. Exp. Sta. Bul. 180:
235-239.

Wiucox, R. B., and Rupoupg, B. A.
1918. SPOILAGE OF CRANBERRIES AFTER HARVEST. U.S. Dept. Agr. Bul.
714, 20 p.

(11) Stevens, N. E.
1917. TEMPERATURES OF THE CRANBERRY REGIONS OF THE UNITED
STATES IN RELATION TO THE GROWTH OF CERTAIN FUNGI.
Jour. Agr. Research 11 : 521-529, illus.

(12) 1923. SOME OBSERVATIONS ON THE RELATION OF WEATHER TO THE
KEEPING QUALITY OF THE CRANBERRY CROP. Ann. Rpt. New
England Cranberry Sales Co. 1923 : 29-35.

(9)

(10)

(13) 1924. NOTES ON CRANBERRY FUNGIIN MASSACHUSETTS. Phytopathology
14 : 101-107.
(14) 1925. FIELD OBSERVATIONS ON FALSE BLOSSOM OF THE CULTIVATED CRAN-

BERRY. Phytopathology 15 : 85-91.
28

GRGANIZATION OF THE
UNITED STATES DEPARTMENT OF AGRICULTURE

October 1. 1926

WCERELAT YL ON GTICULLUM ES Ves pein tee Uy AL W. M. JARDINE.
ALSSUSLATUE IS CChELANY a ee ens Mel a Ay R. W. Dounuap.
Drnector Of Scventejic. Work ee A. F. Woops.
Director of Regulatory Work...-___.__-__-- WALTER G. CAMPBELL.
Directory Latenston Work. 2 22 C. W. WARBURTON.
D7 eciarONe OR MALOnN 2-28 52 Bl a Neuson ANTRIM CRAWFORD.
Director of Personnel and Business Adminis-

BAUD THOT Ie UENCE a ED A gle ee OE EN oes W. W. STocKBERGER.
ASX OVA OOD Sa) Sd 2 a i eR R. W. WILLIAMS.
WKCGt ers UTE Le oars So as eels SW CHarLes F. Marvin, Chief.
Bureau of Agricultural Economics_________- Luoyp S. Trenny, Acting Chief.
Bureau oj; Animal Indusiry 2. 2352282 8 JoHN R. Mouumr, Chief.
Bureau of Plant I eae ce Cask See A esaee Witittam A. Taytuor, Chief.
PUG RE SEDSCTU LEE its, NE Nya eRe ta ages A RENAE W. B. GREELEY, Chief.
TRUE ROE CHLCNDSLT Yo meee 2 ee a oe ee C. A. Browns, Chief.
FS ILGCIL ILE Of SOG) SeMem ates Soman Bn TOR) ad MILTON WHITNEY, Chief.
Buren OjoE NtomMologie® =a ete Ve L. O. Howarp, Chief.
Bureau of biologicaliwurvey 22 so E. W. Neuson, Chief.
BURCEL Of) EAU TOGGS 288 Bisa ie THomas H. MacDona tp, Chief.
iBuneawio MomevEiconomics® 2 2229820 2. LovisE STanLeEy, Chief.
BUTeEGUopmOGAryelnausinye «oe C. W. Larson, Chief.
Office of Hapertment Stations. 220502) oe E. W. Auuen, Chief.
Office of Cooperative Extension Work -_____- C. B. Suiru, Chief.
/ ARAYA RO) Seis TINO NOS: i) SU) VaR ea OE SPN a CLARIBEL R. BARNETT, Librarian.
Rederal Horacultural Board. 23 2222525 0422 C. L. Maruart, Chairman.
Insecticide and Fungicide Board_________-- J. K. Haywoop, Chairman.
Packers and Stockyards Administration. ____ Joun T. Carne III, in Charge.
Grain Futures Administration. _._._..-.-__- J. W. T. DuvgE., in Charge.

This bulletin is a contribution from

EXT CCU ON BERATED LESLIE eet DN WiLuiaAM A.:TayLor, Chief.
Office opti: Diseases. sas on 2208 M. B. Waits, Senior Pathologist, in
! Charge.
29

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