mil

UNIVERSITY OF CALIFORNIA
P COLLEGE OF AGRICULTURE

AGRICULTURAL EXPERIMENTSTATI0N
BERKELEY, CALIFORNIA

APPLE GROWING IN
CALIFORNIA

F. W. ALLEN

BULLETIN 425

May, 1927

Eevised May, 1937

UNIVERSITY OF CALIFORNIA

BERKELEY, CALIFORNIA

1937

CONTENTS

PAGE

Choosing a location for apple growing 4

Apple districts 6

Choice of varieties 12

Description of varieties 15

Securing and caring for nursery trees 26

Establishing the orchard 28

Cultural operations in the orchard 31

Pruning 37

Apple diseases and their control 43

Insect pests and their control 47

Spray program 50

Harvesting 52

Removal of spray residue 56

Packing 60

Storage 68

Storage and market diseases 74

Shipping and marketing of fresh apples 82

Dried apples 83

Canned apples 88

Apples for bakers' use and other apple products 89

Standards of apple-production costs 89

Yields and returns 94

Acknowledgments 95

APPLE GROWING IN CALIFORNIA

F. W. ALLEN1

GENERAL REVIEW OF THE APPLE INDUSTRY

Perhaps because California produces a greater variety of fruits than
any other state and leads in the production of almonds, apricots, peaches,
pears, prunes, and walnuts, as well as lemons and oranges, the impor-
tance of the apple crop is usually underestimated. According to statis-
tics,2 the total production of apples in California in 1927 and in 1930
was exceeded by only two other states — Washington and New York. In

TABLE 1

Production and Value of California Apples, 1926-1935.

Year

Production

Farm value
per bushel,
December 1

Total value

1926

bushels
10,350,000
7,458,000
13,105,000
7,880,000
11,644,000
9,112,000
9,045,000
9,333,000
6,500,000
9,889,000

dollars
0.40
0.90
0.50
0.90
0.55
0.65
0.32
0.50
0.49
0.37

dollars
4,140,000

1927

6,712,000

1928

6,553,000

1929

7,092,000

1930

6,404,000

1931

5,923,000

1932

2,824,000

1933

1934

4,666,000
3,185,000

1935

3,659,000

9,431,600

0.56

5,115,800

Sources of data:

1926-1928: California Cooperative Crop Reporting Service. California
Crop Report, 1928. California State Dept. Agr. Spec. Pub. 96:36. 1929.

1929-1935: California Cooperative Crop Reporting Service, annual re-
ports. Sacramento. (Mimeo.)

1924, 1928, 1929, 1932, and 1933 it was exceeded only by these states
and by Virginia or Pennsylvania. In 1935 the state was fifth in total
production. Only occasionally do Michigan, Ohio, and West Virginia
force California below fifth or sixth rank. The production and value of
California apples during the decade from 1926 to 1935 is shown in
table 1. Yields, in some years, have fluctuated widely, but there has been
an average production of approximately 9% million bushels.

From 1919 to 1925, inclusive, the average farm value of the crop was
$1.20 a bushel. Since 1925 average returns have been only about half

1 Associate Pomologist in the Experiment Station.

2 United States Department of Agriculture Yearbooks, annual issues, 1930-1935.

[3]

4 University of California — Experiment Station

this amount. Despite these low returns in most years, the total value of
the apple crop has averaged approximately two and one-half times that
of either the cherries or the shipping plums, nearly twice that of the
almonds, three-fourths that of the pears, and nearly two-thirds that of
the apricots. These data on production and returns indicate that the
apple is relatively important even though the acreage for 1936 is now
only 70 per cent or less of that for 1925.

New plantings in the past decade have been limited, largely confined
to small areas, and in most counties have not offset older trees that, for
one reason or another, have been removed. Bearing acreage in the Pajaro
Valley is now only about 60 per cent of that for 1925. San Bernardino
County, the third largest apple district of the state in 1925, has no^
dropped from nearly 6,000 acres to approximately 1,600. Other southern
and central San Joaquin Valley counties have suffered similar losses,
while Inyo County, containing 1,000 acres in 1926, is now estimated to
contain less than 100. Mendocino, Humboldt, Butte, Placer, and El
Dorado counties have experienced little change. The bearing acreage in
Napa County has increased slightly since 1928, while that in Sonoma
County has gradually increased over the previous decade. The Sebas-
topol area now contains a slightly greater acreage of trees than the
Pajaro Valley. Tuolumne County, estimated to have had less than 1,000
bearing acres in 1925, doubled that number during the next two years
and has since shown a slight increase. Estimated bearing and nonbearing
acreages of apples in each county of the state may be obtained from the
Agricultural Statistician, State Department of Agriculture, Sacramento.

CHOOSING A LOCATION FOR APPLE GROWING

Apples may be grown under a rather wide range of conditions. A com-
mercial apple orchard, however, represents a long-time investment. In
selecting its location, therefore, one should duly consider such factors
as (1) suitable climatic conditions, (2) good soil, (3) ample water sup-
ply, (4) transportation and market facilities.

Climatic Requirements. — Thought should be given to summer and
winter temperatures, frost damage, winds, and fog.

Apple trees thrive and fruit best under a relatively long, cool, slow,
growing season. Except, perhaps, for early summer varieties in favor-
able locations, apples are not being produced successfully under interior-
valley conditions. Suitable size and good texture are difficult to secure
where high temperatures are combined with low humidity. Furthermore,
sunburn damage is often serious on the fruit. In California, therefore,
the best apple districts are those where summer temperatures are con-

Bul. 425] Apple Growing 5

sidered too low for the optimum development of other tree fruits, except
perhaps pears. For this reason commercial production is limited to
rather definite sections receiving coastal influences or to those in the
interior at an altitude of 2,000 to 4,000 feet. In either of these locations
summer temperatures are moderate.

At elevations of 3,500 feet or higher, and in the Sacramento and San
Joaquin valleys, there is usually enough winter chilling to permit satis-
factory opening of the buds of most varieties in spring. This is true also,
for the varieties grown, in coastal regions in the northern part of the
state. In some southern districts there is very harmful delay in opening
of leaf buds and flower buds in springs following the warmest winters.
Temperatures in any part of the state are rarely so severe as to cause
winter injury to apple trees ; but at altitudes above 3,500 feet the crop
is frequently endangered or even lost by reason of late spring frosts.
Coastal sections are particularly free from frost damage.

Any location subject to strong winds during the growing period should
be avoided. Beside the possibility of blowing the fruit from the trees at
harvest time, much damage may occur through limb rubbing.

Fogs, as already mentioned, may help in coastal sections to break the
rest period of trees in the spring. In the growing season, however, ex-
cessive fog prevents full color development of red or striped varieties
and may also cause more or less russeting, which renders the fruit less
attractive. For these reasons fruit of highest color and finish is usually
produced in fog-free areas at higher altitudes.

Soil. — Apple orchards have been planted both on stiff, heavy clay and
on sandy soils ; but an intermediate type ranging from clay loam to silt
or sandy loam is preferable. Such soils are easier to work than those
which are heavier ; are likely to be more fertile and have a higher mois-
ture-holding capacity than the sandy soils. Good drainage is essential ;
the tree roots should strike to a considerable depth without reaching the
water table. Shallow soils or soils underlaid with hardpan or gravel
should preferably be avoided.

Different varieties of apples often show special suitability to certain
types of soil. In the Watsonville section the Yellow Newtown does better
on heavier soils than the Yellow Bellflower. The Gravenstein, likewise, is
apparently well adapted to the fine, sandy loam of the Sebastopol sec-
tion. "With only a few varieties, however, have such soil adaptations been
determined with any degree of certainty.

Water Supply. — Most apple orchards of California depend entirely
upon natural rainfall for their water supply. Others receive one or two
irrigations. Usually, where the average annual precipitation amounts to

6 University of California — Experiment Station

as much as 20 inches, that amount has been thought sufficient for satis-
factory tree growth. Though it may, under favorable soil and climatic
conditions, produce growth the first few years, it may prove inadequate
after the trees reach bearing age. Even where the rainfall is as much as
40 inches, irrigation is sometimes beneficial, either because of an open,
porous soil of low water holding capacity or because all the rain comes
at one season and some is lost through surface runoff and by deep per-
colation.

Bearing trees need an adequate water supply to produce a large crop
and bring it to proper size. In most sections, rains are not expected dur-
ing the latter part of the growing season ; hence irrigation facilities will
enable one to apply water when most needed.

Transportation Facilities. — Extension of highways and of trucking
facilities has materially decreased the transportation problem of smaller
districts far from their markets. In certain hilly areas, however, several
miles from the highway, fruit must be hauled over unimproved roads.
The grower thus located is obviously at some disadvantage and must use
every precaution to protect his fruit, usually unpacked, from excessive
bruising.

Market Facilities. — Either the larger producing districts are provided
with cooperative or private selling organizations that grade, pack, and
ship most of the crop sold as fresh fruit, or else the fruit passes through
the hands of individual buyers or packers. Apples used for drying may
likewise be purchased by owners of commercial evaporators or dried by
individual growers. In the smaller districts the best part of the dessert
varieties, at least, is sold fresh as orchard-run bulk fruit, being largely
purchased at the orchard by wholesale buyers who do their own hauling.
This method, though convenient, places the grower at the mercy of the
buyer.

APPLE DISTRICTS

As related to the climatic requirements just mentioned, figure 1 shows
the relative importance of apple production in the different counties.
Two-thirds of the total acreage is to be found in Sonoma County and
in the Pajaro Valley in Santa Cruz and Monterey counties. Tuolumne
County is credited with a total of 2,500 acres ; Mendocino and San Ber-
nardino counties with over 1,400 acres each. Other counties containing
small areas but having a total of 250 acres or more are shown in figure 1.
Watsonville District. — The Pajaro Valley or Watsonville area is the
oldest and heaviest-producing section in the state, the annual production
being between 2% and 3 million boxes. The C. O. Silliman family orchard
was planted in 1853 ; and commercial plantings began about 1870, be-

Bul. 425]

Apple Growing

coming most extensive between 1880 and 1890, when practically all the
alluvial or bottom soils fitted for apples were planted. Subsequent or-
chards were started on the rolling, residual soils of the valley and in
the more hilly parts of Santa Cruz County. In recent years there has

Fig. 1. — Outline map of California showing apple acreage by counties.
Data from California Cooperative Crop Reporting Service, 1936.

been relatively little of this activity. Rather, several thousand acres of
the older and more unprofitable Yellow Bellflower trees and miscella-
neous varieties have been removed and largely replaced by vegetable
crops, principally lettuce. Small areas have been planted with pears
and apricots.

Approximately 60 per cent of the apple acreage is of the Yellow New-

8 University of California — Experiment Station

town variety ; 25 to 30 per cent of Yellow Bellflower ; and the remaining
acreage of mixed varieties, mostly Delicious, White Pearmain, and Win-
ter Banana. Newer plantings have been largely of Delicious.

The soils vary from porous sandy loams to clay loams and clays on the
terraces and slopes, and from sandy loams to clays and clay-adobes on
the valley floors. With an average annual rainfall of 20 inches or more,
comparatively cool temperatures, and high humidity, most orchards are
nonirrigated. Some, however, perhaps 20 to 25 per cent — receive one 6 to
8-inch irrigation in July or August, the water being obtained from wells.

Because of the climatic conditions, red varieties may lack high color.
Eliminating a small percentage of the poorest-producing orchards, aver-
age yields probably are from 400 to 450 packed boxes to the acre ; yields
from the best orchards, often as much as 1,000 to 1,200 boxes. Crop
failures are rare.

The major part of the crop is sold to cash buyers who do their own
harvesting and packing. Seasonal contracts are frequently made when
the trees are in blossom. The district is well provided with commercial
packing houses, cold-storage facilities (sufficient to hold 1,400,000 boxes) ,
evaporators, and by-product plants. Some 5,000 to 7,000 tons of evapo-
rated apples are produced annually.

Although fogs are frequent, fungus diseases are relatively few ; apple
mildew and the various fungi causing heart rot or wood decay are the
most troublesome. Codling moth, aphids, and the leaf roller are the most
important insects. Fruit of the Yellow Newtown variety from this section
is subject to discoloration discussed under "Internal Browning."

Sonoma County. — Early plantings of apples in Sonoma County were
made about 1880 ; most rapid plantings between 1900 and 1910. Though
the total acreage now slightly exceeds that in the Pajaro Valley, the
tonnage produced is not so great. Total shipments of packed apples vary
from 700 cars or less in occasional years of short crops to 2,000 cars in
other years. In most years shipments approximate 1,500 cars. About half
of the total production is now dried.

Approximately three-fourths of the apple crop of the county origi-
nates in the Sebastopol area, extending about five miles south of Sebasto-
pol, west to Occidental, and north to Forestville and Trenton. The topog-
raphy there is naturally rolling, the soil being usually a fine sandy loam
with a permeable clay subsoil. Prom the standpoint of climate this re-
gion, though coastal, partakes somewhat of inland- valley conditions. Day
temperatures are considerably higher than in the Pajaro Valley, while
the rainfall is about one-third greater — perhaps 37 inches. Irrigation,
though not generally practiced, would doubtless be beneficial, wherever

Bul. 425] Apple Growing 9

water is available. Although many varieties are grown, between 65 and
70 per cent of the acreage is devoted to Gravensteins. These, harvested in
July, supply the eastern markets with the first boxed apples of the
season. The district is well provided with selling organizations, evapo-
rators, and vinegar plants.

Other areas of the county include those adjacent to Geyserville and
Healdsburg farther north, the small Annapolis section near the coast,
and the Vineburg and Sonoma districts in the southeastern part. Except
in the Annapolis section, where summer temperatures are cooler and the
season about two weeks later, the general climatic and growing condi-
tions in these districts resemble those of Sebastopol. In the Geyserville
and Healdsburg areas, somewhat heavier and also more gravelly soils
prevail, and the topography is flatter. Irrigation is available in a few
orchards. As in the Sebastopol area proper, the Gravenstein is the prin-
cipal variety.

Tuolumne County. — Plantings in Tuolumne County are much less
extensive and generally in smaller units than in the Watsonville or
Sebastopol areas. Nevertheless, with the increase since 1926, bearing
acreage in Tuolumne County is now approximately 2,500 acres. The
principal plantings are in the Yankee Hill, Soulsbyville, Ralph Station,
and Tuolumne districts in the southwestern part of the county at alti-
tudes of 2,300 to 3,500 feet. The general topography is typical of the
Sierra Nevada foothills, rolling to hilly, with many of the orchards on
rather steep slopes and surrounded by timber (figs. 2 and 3).

The nature and depth of the soil varies with the type of rocks from
which it has been derived. Soils obtained from granodiorite are light red
in color, sandy loam to loam in nature, well drained, and from shallow
to 6 feet in depth. Those from the slates and diabase are somewhat
heavier and of a deeper red. All are rather easily cultivated, but such
work is often difficult or inadvisable because of the steepness of the slope.

Irrigation water at approximately 25 cents a miner's inch is obtained
from the south fork of the Stanislaus river and nearly all orchards re-
ceive one or two irrigations annually at a cost of $7 to $12 an acre.

San Bernardino County. — Apple acreage in San Bernardino County,
which in 1925 was 6,000 acres, is now only about 25 per cent of this
amount. The Yucaipa district on the mesa lands east of Redlands at ele-
vations of 2,000 to 3,000 feet has had the acreage greatly decreased. High
cost of water for irrigation and winter temperatures too mild for an
adequate dormant period of the trees are the main reasons for the de-
cline. Some of the acreage has been replanted with freestone peaches,
and a small amount with oranges and grapefruit. The leading apple

10

University of California — Experiment Station

Fig. 2. — General view of Tuolumne County apple section between
Sonora and Tuolumne.

% %

M

' ='' ■ -^l^^^i?^

Fig. 3.

-Hillside apple orchard near Sonora, Tuolumne County,
at 3,000 feet elevation.

varieties have been Rome Beauty, Winesap, Delicious, and King David.
In the adjoining district of Oak Glen, at elevations of 4,000 to 5,000 feet,
climatic conditions — except for late spring frosts — have proved more
suitable for apple production ; and little change has occurred. Plantings

Bul.425] • Apple Growing 11

at Chino in the southwest part of the county have been almost eliminated ;
likewise those at Adelanto. The apple acreage in the desert districts near
Victorville, of which Apple Valley is the most important, has declined
approximately 50 per cent. In general, probably apple growing in San
Bernardino County will become more and more limited to small local
areas in the foothill and mountain districts.

Mendocino County. — Orchards of Mendocino County are somewhat
scattered, with the main center of production in the Anderson Valley
about midway between Ukiah and the coast. From 4,000 to 5,000 tons
are produced annually. The orchards are located on cutover redwood
lands, and the trees are grown without irrigation. Jonathan, Baldwin,
Rome Beauty, Rhode Island Greening, Gano, King, Ben Davis, Deli-
cious, Winter Banana, and Wagener, as well as many less popular varie-
ties, are grown successfully. Much of the crop is dried by individual
growers in their own dehydrating plants. In the last few years, however,
approximately 500 tons have been sold direct to fresh-fruit markets, San
Francisco and local dealers purchasing the fruit at the orchards and
doing their own hauling. Although with proper attention to spraying
and other orchard operations, excellent apples can be produced, the total
tonnage has not warranted a definite general market for packed fruit.

Besides the districts mentioned above, from 400 to 800 acres of bearing
trees are found each in the following counties.

Santa Clara County. — Most of the apple orchards of Santa Clara
County are in the San Francisco Bay region, from Mountain View to
Milpitas, with a smaller number in the mountain sections. Yellow New-
town, White Pearmain, Smith Cider, Alexander, White Astrachan, and
Yellow Bellflower are the leading varieties. At present the acreage is on
the decrease, the section being apparently better suited to pears.

San Diego County. — Production in San Diego County is confined to
the Encinitas and Escondido districts near the coast, with White Pear-
main, Rome Beauty, and Yellow Newtown as the leading varieties, and
to the mountain sections around Witch Creek, Santa Ysabel, Warner
Springs, Julian, Cuyamaca, and Palomar. Most standard fall and winter
varieties are grown in these sections of higher elevations, Delicious be-
ing perhaps of greatest importance. Although most of the crop is mar-
keted locally, there are some truck shipments to Los Angeles.

Napa County. — The apple acreage in Napa County runs heavily to
Gravensteins, the Carneros section southwest of Napa being the princi-
pal district.

Butte County. — Three-quarters of the bearing apple acreage of Butte
County is located adjacent to Paradise at elevations of 1,000 to 2,000

12 University of California — Experiment Station

feet. Most winter varieties are grown, but Delicious predominates. Ap-
proximately 150 acres of apples are located in the Chico-Durham dis-
trict.

Humboldt County. — Conditions in Humboldt County resemble those
in Mendocino, but with orchards even more scattered.

Kern County. — Commercial production in Kern County centers near
Tehachapi at altitudes ranging between 3,000 and 4,500 feet. Jonathan,
Gano, Arkansas Black, Winesap, Delicious, and Winter Banana are the
main varieties. Most of the crop is sold in Los Angeles and Bakersfield.
Unfavorable weather conditions at blooming time, blight, lack of water,
and absentee ownership have often reduced the profits. Acreage has been
materially reduced during the last few years.

Contra Costa County. — Commercial apple production in Contra Costa
County is limited to a few orchards in Happy, Reliez, and Alhambra
valleys. Yellow Newtown, Spitzenburg (Esopus Spitzenburg), Winter
Banana, and Yellow Bellflower are probably the main varieties.

Placer and El Dorado Counties. — Apple orchards in these two counties
are scattered throughout the fruit-growing districts at elevations of
2,000 to 3,000 feet. The fruit has been marketed locally. Numerous fall
and winter varieties are grown.

Los Angeles County. — Apple production in Los Angeles County has
declined markedly during the past decade, most of the acreage being
now confined to the Antelope Valley north of the Tehachapi range.

CHOICE OF VARIETIES

Of several thousand named varieties of apples, twelve or fifteen com-
prise most of the commercial crop of the United States. In California a
large proportion of the crop is limited to Yellow Newtown, Gravenstein,
and Yellow Bellflower. Some of the less-grown commercial sorts, how-
ever, prove, under certain conditions, as profitable as these three — in
some instances more so. In fact, more of the recent plantings have been
of other standard varieties or their newer strains. The varieties grown
primarily for home use are largely a matter of personal preference, but
those grown commercially must promise profitable returns. Varieties
for a commercial orchard should therefore be chosen after a considera-
tion of the following factors.

Adaptability to the Section. — In districts of commercial importance
there are usually several varieties better adapted to the existing climatic
and growing conditions and more profitable than others. Since these va-
rieties have been determined by trial, they serve as a valuable guide for
future plantings. It does not necessarily follow, however, that additionaJ

Bul. 425] Apple Growing 13

plantings of these are to be recommended. Present production may
already exceed the demand, or some other condition may make the plant-
ing of other sorts more desirable. Watsonville, for example, under coastal
conditions where the ordinary red varieties usually fail to color well,
has specialized in Yellow Newtown and Yellow Bellflower, both yellow
varieties. Though the Yellow Newtown plantings are extensive, the fruit
usually lacks the smooth finish of that grown in other districts and often
fails to keep well in storage. The crop of Yellow Bellflower is also often
larger than can be disposed of profitably. For these reasons it is doubtful
whether these varieties should be included in any new planting. Other
green or yellow sorts, such as Golden Delicious, Winter Banana, White
Pearmain, or some of the newer red strains of Delicious, Jonathan, or
Rome Beauty are among those considered most favorable.

The Sebastopol district has specialized in the Gravensteins ; but as
these are now produced in larger quantity than can be profitable, addi-
tional plantings are not recommended. New orchards contain other sorts,
primarily red strains and particularly Red Rome Beauty.

At low altitudes in the valleys where high summer temperatures exist,
only fast-growing, early-maturing apples are suggested. With late varie-
ties the growth of the fruit is checked somewhat during the middle of
the summer ; and early dropping, small size, and poor texture generally
result. Where strong winds during the late summer often blow a con-
siderable part of the crop from the trees, an effort should be made to
secure early-maturing varieties and to avoid those that have a natural
tendency to drop.

Variety Characteristics. — Besides this fault of dropping, one should
consider vigor of trees and regularity of crops. Weaker-growing varie-
ties, such as Grimes Golden or Wagener, those particularly susceptible
to prevalent diseases, and those of irregular bearing habits, as Spitzen-
burg and Northern Spy, should be avoided unless they have proved
profitable despite the higher cost of production. Although quantity may
sometimes be sacrificed for quality, in commercial orchards this policy
is practical only within certain limits. Good storage qualities are desired
in late varieties, while with summer varieties the general time of ripen-
ing is important.

Provision for Cross-Pollination. — As pollination experiments have
shown, most varieties of apples under California conditions are either
unfruitful or unable to set satisfactory crops when self -pollinated. Ac-
cording to Philp and Vansell,3 solid plantings of Baldwin, Early Har-

3 Philp, G. L., and G. H. Vansell. Pollination of deciduous fruits by bees. California
Agr. Ext. Cir. 62:1-27. 1932.

14 University of California — Experiment Station

vest, Grimes Golden, Oldenburg, Wagener, Wealthy, Yellow Newtown,
and Yellow Transparent will usually set commercial crops. Cross-pol-
lination, however, has generally resulted in larger yields. Ben Davis,
Gano, Jonathan, Spitzenburg, Rome Beauty, Tompkins King, and York
Imperial may be self -fruitful in some years. Other varieties, including
Yellow Bellflower, Gravenstein, Delicious, Mcintosh, Winesap, Stay-
man Winesap, White Pearmain, and Winter Banana, are usually self-
unfruitful and should definitely be interplanted with some other variety
for cross-pollination. Apples of the Winesap group, including Winesap,
Stayman Winesap, Arkansas, and Arkansas Black, appear to be un-
fruitful even when interplanted.

Except for these apparent cases of unfruitfulness between varie-
ties, one need consider only the season of blossoming and sometimes the
relative amount of pollen produced. Summer varieties usually bloom
somewhat earlier than fall or winter varieties. Winesap, Stayman Wine-
sap, and Gravenstein are rather poor pollen producers and are unde-
sirable as pollinizers of other varieties. As Delicious usually produces
abundant pollen, this variety or Yellow Newtown is recommended for
pollinating Gravenstein.

Market Demands. — Although home orchards may cater to one's per-
sonal taste, commercial orchards should contain only varieties of recog-
nized importance for which a good demand exists. The average retail
buyer of apples for dessert or cooking has a very limited knowledge of
varieties and usually confines his purchases to those with which he is
familiar or else to some variety particularly attractive in appearance.
If the latter fulfills his expectations as to quality, a demand will soon
develop. Delicious, easily recognized by the prominent knobbing around
the blossom end, quickly gained a reputation and has risen to prominence
because of its pleasant flavor. The flesh, however, quickly becomes over-
ripe ; and the variety is of little value for cooking.

Besides the original Delicious, both red and yellow strains of this
variety are now gaining in popularity for eating fresh. For baking pur-
poses the large size, smooth shape, and good culinary qualities of the
Rome Beauty make it the leading variety. The superior storage qualities
of Winesap and Yellow Newtown make these prominent late commercial
varieties.

Such examples show that each commercial variety grown should fill
some definite market demand — preferably better than most other com-
peting varieties. Since, however, the demand for any particular variety
is limited, excess planting will result disastrously. Under certain cir-
cumstances a limited quantity of some inferior variety ready for mar-

Bul. 425] Apple Growing 15

keting at just the right time may prove more profitable than some better
variety that has been overplanted.

Previously little attention has been given to varieties for drying;
almost any sort unsuitable to be sold profitably as fresh fruit went to the
dehydrators. Many miscellaneous varieties will continue to be utilized
thus ; but with a demand for a better and more attractive dried product,
those varieties giving the largest yield per ton of fruit dried and those
drying with the best color and quality will prove most profitable. Yellow
Newtown and Rhode Island Greening probably have preference over
other California varieties. Gravenstein and Yellow Bellflower are also
popular. (See discussion of drying.)

DESCRIPTION OF VARIETIES

The following descriptions include the most important commercial varie-
ties of the state and several considered valuable for home use. They are
listed in their approximate order of ripening, although there will be
considerable variation in this respect, according to the section. The
season given after each variety represents the period of greatest use.
The illustrations shown (plates 1^) are approximately half size.

Yellow Transparent. — Origin, Russia. An important early variety in
the eastern states ; little grown in California. Fruit of good size, roundish
conic, attractive greenish to whitish yellow ; skin thin ; flesh white, mod-
erately fine-grained, tender, sprightly subacid; excellent for cooking
purposes. Defects : fruit easily bruised ; tree subject to blight, though
moderately vigorous. Suggested for trial as an early yellow apple under
valley conditions. Season, June 15 to July 15.

Red Astrachan. — Origin, Russia. The variety is widely known and is
recommended for early home use and for local markets. Fruit is of me-
dium size, rather irregularly shaped, usually roundish to slightly flat-
tened; skin thin and tender, greenish yellow to striped or deep red,
covered with a pale, bluish bloom. Flesh white, juicy, crisp, of good
quality for both dessert and cooking. Tree hardy, vigorous, an early and
regular bearer. Principal defects : fruit not uniform in size, often small,
inclined to drop, not a good shipper. Season, July.

White Astrachan. — Origin, Russia. Well adapted to most parts of the
state and recommended for commercial planting as a summer variety in
the Sacramento and San Joaquin valleys. Fruit large to very large,
almost round, flattened at each end; skin greenish white, with faint
streaks of red, and covered with white bloom. Flesh white, juicy, crisp,
somewhat coarse and acid; primarily a cooking variety. Tree large,
vigorous, productive. One of the best early varieties for local market.

16 University of California— Experiment Station

Fruit too easily bruised to be shipped long distances. Season, July and
August.

Gravenstein. — Origin, probably Germany. The most popular and most
extensively grown summer apple in California. About 1,500 carloads
annually (the best of the crop) are packed and shipped to eastern fruit
markets as early boxed eating apples. Fruit medium to large, slightly
flattened, broad at the stem end, a little one-sided or angular. Stem short,
deeply set in the cavity. Skin greenish yellow to orange yellow overlaid
with broken stripes of light and dark red. Flesh tender, crisp, highly
aromatic. Of very good to best quality both as a summer dessert and as
a cooking apple. Trees usually large and vigorous, coming into bearing
rather early and producing good crops. Chief defects : tendency to drop
badly ; high percentage of windfalls ; susceptibility to bitter pit ; neces-
sity of several pickings because of irregular size and coloring ; difficulty
of removing one specimen from a cluster without the others dropping.

A good variety for both commercial and home use. Season in Sonoma
County, July and August. Some interest is now being manifested in the
red bud sports of this variety, which are of practically solid red color.
One of these has been named Banks.

Alexander. — Origin, Russia. Rather widely distributed in the United
States but of limited planting in California. One of the most important
summer varieties in Santa Clara and Napa counties. Fruit large, round-
ish conic to slightly oblate conic ; red or striped. Flesh white to slightly
yellow, rather coarse, but of fair quality for cooking. Common defects :
cracking of the skin and flesh around the stem ; premature dropping.
Continuous ripening over a period of several weeks. Trees vigorous, but
not always good bearers. Season, July and August.

Mcintosh. — Origin, Canada. Excellent for home use ; well adapted to
local markets. Not recommended for commercial planting because of
tender flesh, susceptibility to apple scab, tendency to drop prematurely.
Fruit medium and uniform in size, roundish to roundish oblate ; regular
or faintly ribbed. Skin thin, smooth, tender, readily separated from the
flesh. Color bright red, striped with carmine to dark purplish red with
stripes obscure, overspread with thin lilac bloom. Flesh very tender,
usually snow white, fine-grained, crisp, tender, very aromatic. Flavor
mild subacid to sweet. Quality very good to best. Season, September and
October.

Rhode Island Greening. — Origin, probably Rhode Island. Often found
among the older orchards in the coast counties. Popular for drying be-
cause of heavy yields of dried fruit, but never grown extensively in
California. Fruit medium to large, roundish oblate, dark green to green-

a. Yellow Transparent

b. Red Astrachan

c. White Astrachan

d. Gravenstein

e. Alexander /. Mcintosh

Plate 1. — Apple Varieties

[17]

a. Rhode Island Greening

b. Yellow Bellflower

c. Jonathan

d. King David

e. Tompkins King /. Grimes

Plate 2. — Apple Varieties

[18]

a. Winter Banana

&. Delicious

c. White Pearmain

d. Wagener

e. Baldwin /. Esopus (Spitzenburg)

Plate 3. — Apple Varieties

[19]

a. Stayman Winesap

b. Eome Beauty

c. Winesap

d. Gano

e. Yellow Newtown /. Arkansas Black

Plate 4. — Apple Varieties

[20]

Bul. 425] Apple Growing 21

ish yellow. Flesh yellow, fine grained, tender, juicy, sprightly subacid.
Quality very good. Season, fall and early winter.

Yellow Bell flower. — Origin, New Jersey. One of the best-known early
fall market varieties grown in the state — in the Pajaro Valley, second
only to Yellow Newtown. Fruit large, oblong, ribbed, and tapering to-
ward the blossom end. Skin lemon-colored to yellow, marked with promi-
nent dots and with a pink blush on the exposed cheek. Flesh nearly white,
tender, juicy, and crisp, with subacid flavor. Quality not high, but a
good fall variety for general use. Tree a strong grower and good pro-
ducer. Fruit variable in size and quality, requiring careful handling.
Prices usually lower than for later varieties. Season, September to
November.

Jonathan. — Origin, New York. A seedling of the Spitzenburg and in
numerous respects not dissimilar. Important in San Bernardino, San
Diego, Mendocino, Humboldt, and Sonoma counties. Usually successful
where fall and winter apples are grown. Similar to Spitzenburg in shape
and color but without the conspicuous dots on the skin. Flesh light
yellow, tender, juicy, sprightly subacid, of excellent quality for all pur-
poses. A good storage variety for a fall apple. Tree vigorous under good
conditions, early-bearing, a good producer. Season, September to Jan-
uary.

Where Jonathan fails to attain a solid red color, planting of the red
strains is suggested. One of these listed by nurserymen is given the trade
name of Blackjon.

King David. — Origin, Arkansas. A very rich-red apple about the size
of the Jonathan and somewhat similar ; not of so high dessert quality,
but a very attractive market variety, planted to a considerable extent
for the fall trade. Fruit of medium size, roundish conic, usually deep
solid red. Flesh yellow, firm, crisp, moderately tender, of good quality.
Season, September to December.

Tompkins King. — Origin, New York. Secondary in commercial impor-
tance, grown in mountain sections, popular in Humboldt and Mendocino
counties. Fruit large, round or globular, angular or ribbed, yellowish,
shaded with red and striped and splashed Avith bright carmine ; dots
numerous and conspicuous. Flesh yellowish, moderately coarse, rich,
juicy, tender. Mild subacid flavor ; very good quality. Season, Septem-
ber to October.

Grimes. — Origin, West Virginia. Better known as Grimes Golden.
Highly esteemed as both a dessert and a culinary apple but grown to
only a limited extent. Defects : necessity for careful handling ; tendency
of trees to make a weak growth and produce light crops. Excellent for

22 University of California — Experiment Station

home use wherever produced successfully. Fruit clear, rich yellow;
medium to large ; roundish oblong ; often flattened or truncated at the
ends. Basin or depression at blossom end abrupt, deep, moderately wide.
Skin tough, covered with light russet dots. Flesh yellow, firm, tender,
crisp. Flavor mildly subacid, rich, aromatic. Quality excellent. Season,
fall and early winter.

Winter Banana. — Origin, Indiana. If well grown, one of the most
beautiful varieties. Fruit large, shapely, pale waxed yellow, with a de-
cided pink or sometimes red cheek. Usually characterized by a distinct
suture line on one side extending from the basin to the cavity. Flesh pale
yellow, crisp, tender, mildly subacid, of a distinct musky fragrance.
Quality very good. Very easily bruised ; not well suited for commercial
handling. Grown in both foothill and coastal sections. Season, October to
November.

Delicious. — Origin, Iowa. As a dessert apple, widely and favorably
known. Found in most apple sections; planting gradually being ex-
tended. Fruit very characteristic in shape, usually decidedly tapering,
somewhat irregular, with five very prominent knoblike protrusions at
the blossom end. Dull, dark red color, if well grown. Flesh white, fine
grained, very mildly acid, aromatic, of delightful flavor and excellent
dessert quality. A general favorite on the fruit stands ; always sold at a
premium. Tree one of the strongest and most vigorous growers, aphid-
resistant, blooms late, and is a good pollinizer. Defects : poor flavor un-
less well colored ; failure to cook well ; tendency to drop and under ordi-
nary temperatures to become mealy. Season, October to January.

Because of the lack of color, wide interest is now being shown in the
red bud sports of this variety. These may be offered by nurserymen
simply as Red Delicious or under such trade names as Richared Delicious
or Starking Delicious. The only essential difference between these sports
and the original Delicious is in color.

Golden Delicious. — Origin, West Virginia; discovered as a chance
seedling about 1890 and introduced by Stark Bros, of Louisiana, Mis-
souri, in 1916. Already important as a yellow apple of high dessert
quality. Of separate origin and unrelated to the original Delicious. Fruit
clear yellow, with small conspicuous russet dots about the stem end.
Medium to large, oblong conic, smooth to somewThat ribbed, with a deep
acuminate cavity and a rather long slender stem. More uniform and
regular in shape than Yellow Bellflower; longer and more conic than
Grimes Golden. Flesh is greenish cream in color, firm, crisp, fine-grained,
tender, juicy, aromatic, mildly subacid. Also reported to be good for
culinary purposes and for storage. Season, October to February.

Bul. 425] Apple Growing 23

White Pearmain. — Origin, uncertain. An old favorite variety of high
quality, adapted primarily for home use and local trade. Rather widely
adapted, but grown in California primarily in sections having coastal
influences where red sorts do not color well. Trees vigorous; regular
bearers. Fruit medium to large, oblong conic, pale greenish, often with
a decided blush on the exposed cheek. Surface of the skin covered with
numerous small brown dots. Flesh yellowish, tender, crisp, juicy, very
mildly subacid, of excellent flavor, somewhat resembling Delicious. Sea-
son, October to January.

Wagener. — Origin, New York. Relatively unimportant in the state,
but often found in Mendocino, Humboldt, Napa, and Sonoma counties.
Under favorable conditions, an excellent fall and early winter variety,
but not one of good keeping or shipping quality. Trees small, upright in
habit of growth, coming into bearing early. Only moderately vigorous,
but usually productive of good crops. Fruit of medium size, character-
ized primarily by its flat or oblate shape and by broad ribbing from stem
to blossom end. Skin bright pinkish red, striped with darker red and
often streaked with a thin, whitish covering. Flesh whitish, moderately
firm, fine-grained, tender, crisp, and juicy. Flavor sprightly subacid.
Quality very good to excellent. Season, October to December.

Baldwin. — Origin, Massachusetts. The variety that formerly consti-
tuted about half the commercial crops of New York and the New Eng-
land states. In California, found only in small plantings in the northern
coast counties and in elevated regions. In certain sections, well adapted
and grown to a high degree of perfection ; in others, unsatisfactory in
color. Fruit (when well grown) large, roundish conic ; deep, bright red,
with a few rather distinct dots. Flesh yellowish-white, crisp, juicy, ten-
der, and mildly subacid. Quality very good and adapted for general
market, dessert, and cooking. Season, October to December.

Esopus Spitzenburg. — Origin, New York. Usually known simply as
Spitzenburg. An almost unexcelled market variety, of high quality for
dessert and cooking. Fruit of good size, uniformly shaped, varying from
oblong to conic. Skin smooth, covered with rich red and marked with
numerous conspicuous yellowish dots. Flesh yellowish, firm, crisp, ten-
der, juicy, sprightly subacid. One of the most attractive varieties grown.
Costly to produce, planting therefore generally on the decline. Defects :
tendency toward shy and irregular bearing ; susceptibility (despite gen-
eral healthiness) to apple scab, aphids, and (in some sections) blight;
long, polelike branches, somewhat difficult to control in pruning ; plant-
ing in California therefore limited. Season, November to February.

Stay man Winesap. — Origin, Kansas. Successful in the foothills,

24 University of California — Experiment Station

mountain valleys, and at points of higher altitudes in the interior val-
leys. In many respects similar to its parent, the Winesap ; unlike it in
possessing less color but growing to larger size. Flesh more tender than
Winesap, requiring careful handling, keeping quality poorer. Char-
acterized as medium to large, round conic, with smooth, thick skin cov-
ered with dull red and marked with light gray and russet dots. Flesh
yellow, fine-grained, very tender, crisp, juicy, pleasantly subacid. Des-
sert quality very good. Defects : failure to color properly in certain sec-
tions ; tendency to drop when mature ; necessity of careful handling ;
susceptibility to scald in cold storage. Season, November to December.

Blaxtayman and Staymared, two bud sports of Stayman Winesap,
have somewhat more red color.

Rome Beauty. — Origin, Ohio. One of the leading commercial apples of
the country, with an established reputation in all markets. Not of high
dessert quality, but especially attractive for baking. Good for handling
and shipping. Because of its late blooming habit, recommended for
higher altitudes, especially where late spring frosts make growing of
other varieties precarious. Trees of only medium size but, under good
conditions, vigorous and early-bearing, and producing uniform crops.
Defects : fruit borne especially on the ends of branches, which may whip
badly in high winds; variety rather subject to attacks of aphids. Fruit
uniformly large, smooth round to round conic; skin thick, smooth,
yellow, shaded and striped with bright red to solid red on the exposed
cheek, sprinkled with conspicuous yellow dots. Stem set in a very broad,
shallow, usually green cavity. Flesh yellow, firm, crisp, mildly subacid,
quality fair. Season, October to February.

Rome Beauty is another variety having one or more red bud sports,
essentially the same apple as the parent except that the fruit is mostly
of solid red color.

Winesap. — Origin unknown. One of the oldest and most cosmopolitan
sorts, a general market favorite as a late winter variety. Grown in almost
every apple section of the country. In California, adapted to most sec-
tions other than those exposed to coastal conditions and those of the hot
interior valleys. Excellent in foothills and mountain sections. Trees vig-
orous, productive. Tendency for old trees to overbear and produce small
fruit, necessitating thinning of the crop. Fruit of medium size, roundish
to conical ; skin tough, smooth, bright to dark red, with small scattering
dots. Flesh yellow, firm, crisp, sprightly subacid. Good to very good
quality for both dessert and cooking. Season, November to April.

Gano. — Origin uncertain, probably Missouri or Tennessee. Often
called Black Ben Davis ; similar if not identical to Ben Davis except in

Bul. 425] Apple Growing 25

color. Not largely grown in California except for a considerable acreage
in different districts of higher altitudes. Low in dessert quality but ex-
cellent for shipping ; one of the best-keeping sorts. Trees similar to Ben
Davis, growing rapidly, bearing early, regularly, and abundantly. Fruit
medium to large ; roundish conic ; regular, symmetrical, and uniform in
size and shape. Skin smooth, waxy, light yellow, but mostly overlaid
with pinkish to dark-purplish red, more or less obscurely striped ; pre-
vailing color red. Dots numerous, small, inconspicuous. Flesh white to
slightly yellow, firm, rather coarse, mildly subacid. Season, November to
February or later.

Yellow Newtown. — Origin, New York. Easily the first commercial win-
ter variety grown in the state, over 1% million boxes being shipped an-
nually from the Pajaro Valley. Commercial production confined almost
entirely to that section. Defects : a russeting of the skin under Pajaro
Valley climatic conditions, detracting somewhat from the general ap-
pearance ; susceptibility to browning around the core in storage. Trees
rather slow-growing but productive and reasonably early-bearing. Ex-
cellent for late winter use and probably the most desirable California
variety for drying. Fruit large, roundish to slightly flat. Skin green to
yellow, often with brownish red cheeks. Flesh cream, firm, crisp, juicy,
very good in quality. Season, December to May.

Arkansas Black. — Origin, Arkansas. Often confused with Arkansas
or Mammoth Black Twig. Grown in California to only a limited extent.
Suggested by nurserymen as suitable for interior section. Of some com-
mercial importance in Butte County. Fruit roundish and uniform, of a
very attractive dark color. Skin decidedly "waxy" or "oily" to the touch.
Flesh a deep cream, very firm, moderately fine-grained, crisp, moder-
ately juicy. Of good flavor, excellent for storage, but not an apple of
high quality. Time of ripening, late fall.

Crab Apples* — Of comparatively small commercial importance, but
highly regarded for jelly making and preserving. Grown for home use
and for a limited demand on local markets. Most important varieties :
Whitney, Transcendent, Hyslop, Montreal Beauty, Large Red Siberian.
Of these the first three are perhaps in greatest demand commercially.
Red Siberian is reported as being successfully grown in most parts of
the state.

4 For detailed descriptions of crab-apple varieties see :

Beach, S. A. Apples of New York. Vol. 1. p. 251-69. Illustrated. New York State
Dept. Agr., Albany, N. Y. 1905.

Wickson, E. J. California fruits. 10th ed. p. 215. Pacific Sural Press, San Fran-
cisco, Calif. 1926.

Hedrick, U. P. Cyclopedia of hardy fruits, p. 72-76. The Macmillan Co., New
York, N. Y. 1922.

26 University of California — Experiment Station

SECURING AND CARING FOR NURSERY TREES

Since cultivated varieties of fruit trees rarely come true to type when
propagated from seed, seeds are used only to produce nursery seedlings
upon which the desired varieties are budded or grafted. To produce
nursery stock successfully requires time, patience, and a certain skill
obtained only by experience. Apple growers therefore usually purchase
from a nurseryman. In some instances, however, individual growers wish
to produce their own trees. They may desire additional specimens of
some particular variation, some unknown variety, or some general favor-
ite no longer commercially propagated.

Bud or Scion Wood. — If the trees are to be propagated by budding,
bud sticks of the present season's growth may be collected, at the time
needed, from the variety or particular tree to be propagated. With
apples, budding is usually done from July to September or at least as
long as the bark of the stock will slip. Where propagation is by grafting,
scions of the past season's growth are collected while dormant and are
either used immediately or stored in a moist, cool place until desired.
Root or bench grafting is usually employed, being done indoors at any
time during the winter season, and the grafts held in moist sand or
sphagnum moss until ready for planting. Scion wood the approximate
diameter of a lead pencil is usually preferable to that which is smaller.5

Where one has space for only a tree or two and wishes a number of
varieties, two or more kinds may be budded on an individual stock. Some
nurserymen are now offering apple trees where each of the three to five
main branches have been budded or grafted to a separate variety.

Rootstocks. — Unlike most other deciduous fruits, which may be grown
upon the rootstock of an entirely different fruit, the apple is limited to
the apple root. Even unions with its near relative, the pear, are not suc-
cessful. Individuals wishing to propagate their own trees may either
purchase the necessary apple seedlings to be used as stocks or may grow
these from seed obtained from dehydrators or by-products plants.

Previously, nurserymen produced most of their trees on "French
crab" stock, the seed presumably coming from the native seedlings of
France. In recent years, however, because of inability to secure this seed
in sufficient quantities or in time for fall planting, most apple stock is
now produced from the seed of our own cultivated varieties. The con-
sensus of opinion is that these produce stock just as satisfactory as the
imported seed.

5 For detailed description and illustrated methods of handling seeds, budding, and
grafting see : Hansen, C. J., and E. R. Eggers. Propagation of fruit plants. California
Agr. Ext. Cir. 96:1-52. 1936.

Bul. 425] Apple Growing 27

Most California nurserymen purchase their rootstocks from nurseries
in the northwest who specialize in growing stocks. Washington nursery-
men report8 Delicious, Winesap, Rome Beauty, and Stayman Winesap
seed as producing excellent rootstocks. Although some use Jonathan,
others feel this variety is not satisfactory. Yellow Newtown seed is also
used by some Oregon nurserymen. Seed of these varieties is secured in
quantity at reasonable cost from apple-processing plants. Nurserymen
who do not wish to use the Jonathan seed largely eliminate it by waiting
until most apples of this variety have been utilized. Aside from this no
other attempt is made to segregate different commercial varieties.

Besides Rome Beauty, Delicious, and Jonathan, the New York Agri-
cultural Experiment Station has also found Wealthy, Ben Davis, and
Whitney seed well adapted for rootstocks. Gravenstein, Baldwin, and
Rhode Island Greening were less satisfactory. Certain types of Paradise
rootstock are used where dwarf trees are desired.

Age and Grade of Nursery Trees. — Good commercially propagated
trees may be purchased from any reliable nurseryman. The trees in
greatest demand for planting are those with one-year-old tops. Because
the two-year-old tree receives greater injury to its roots when being
transplanted, perhaps it does not come into bearing earlier than the one-
year-old. The latter also usually possesses enough good buds on the stem
to form scaffold branches where desired.

Formerly nursery trees were graded only according to height, but
now the leading nurserymen consider also the diameter of the main stem
and usually grade or classify one-year-old trees into the following
groups :

4-6 feet high, y2 inch or over in diameter.
3-4 feet high, % to % inch in diameter.
2-3 feet high, % to % inch in diameter.

The price naturally varies with the size and grade. It is doubtful
whether the smallest sizes should be purchased if one can secure those
that have made a better growth. Regardless of age or size, the main stem
of the tree should be reasonably stocky, the bark clean and smooth, and
the top well supplied with good buds or well-spaced branches. It should
also possess a good union where the bud or the scion was inserted into
the stock. If this union has not grown together properly, various fungus
troubles are likely to enter at this point and shorten the life of the tree,
or it may break off several years after being planted in the orchard.

Trees from a nursery should be ordered well in advance so that the
desired varieties may be secured.
6 Personal correspondence.

28 University of California — Experiment Station

Care of Nursery Trees. — The trees, when received, should be removed
from the original package and, unless planted immediately, should be
heeled-in at some convenient place, preferably one not exposed to the
afternoon sun. Where trees ordered from a distance arrive in a dry
condition, the roots may be soaked in water for several hours before
heeling-in. If the branches also appear dry, the entire tree may be put
in the soil and covered for several days.

ESTABLISHING THE ORCHARD

Preparing the Land. — Proper preparation of the land before planting
gives the trees a more satisfactory start; their growth the first season
often determines their future productivity and profitableness.

Though the orchards in the larger apple sections of the state are on
land cleared and cultivated for a good many years, some new plantings
are on virgin soil.

Where the land was formerly devoted to grain crops one should plow
several inches deeper than before in order to break up any plow sole. In
some instances subsoiling in the tree rows may be desirable. This should
always be done in the fall before planting. Except on steep slopes, where
washing may occur, the land may also be plowed in the fall. Fall-plowed
land, left rough, will absorb the maximum amount of moisture during
the winter and may be planted earlier in the spring. Thorough disking
and harrowing usually suffice to put the soil in good friable condition.

Land long cultivated or devoted to grain crops is apt to be deficient in
organic matter. Such soils may well receive, the fall before planting, an
application of barnyard manure, 15 to 20 tons to the acre ; or the land
may be sown to some green-manure crop that can be turned under the
following spring. The latter practice is growing in importance as animal
manures are becoming more difficult to secure.

In the smaller apple sections, particularly at considerable altitudes,
much of the land is more or less heavily timbered, so that considerable
work is necessary to prepare it for planting. In some instances the
method followed is only to cut and remove the timber, dig the holes, and
plant the trees among the stumps. Although some of these trees, because
of the very fertile soil, have made good growth, subsequent plowing and
cultivation are difficult. Unless the stumps are of a wood that decays so
rapidly as to be out of the way after a few seasons, the most economical
plan is to dispose of them at once. Oak and redwood stumps are very
slow to decay.

Although most California apple orchards depend upon natural rain-
fall for their moisture supply, many probably would have been much

Bul. 425] Apple Growing 29

benefited had the land been graded and irrigation facilities provided.
Leveling for orchards consists mostly in cutting off the high points and
depositing the soil in low places. The slope of the land as a whole is
usually made as uniform as possible. The system of irrigation used
should be adapted to the slope and the amount of water available.

Laying Out the Orchard. — To properly lay out an orchard requires
considerable care. Mistakes difficult or impossible to correct can often be
prevented by first carefully mapping the proposed orchard on paper,
spacing the trees according to scale at the distances decided upon, locat-
ing roadways and possible irrigation ditches. Such a map enables one
to see how many trees of a given variety are needed and how they may be
spaced to the best advantage. If properly labeled and preserved, it is
also a ready reference as to the location of any given tree.

Of the different systems of planting, the square is the most popular
and convenient, except on very rolling land, where contour planting is
recommended. The quincunx system — in reality the square method with
a tree in the center of each square — is adopted where the orchard is inter-
planted with temporary or filler trees.

Planting the trees too close together has been a general mistake in most
of the early orchards, many trees having been set 20 to 24 feet apart.
These are now crowding badly and need severe pruning, and the fruit
is difficult to harvest.

The distance of planting apple trees varies somewhat with the variety
and soil conditions. The larger and more spreading varieties such as
Gravenstein, Jonathan, and Winesap should be planted at somewhat
greater distances than the upright-growing sorts such as the Red June
and Rome Beauty. Deep loam or clay loam soils will produce larger trees
than the lighter soils. The planting distance may also vary somewhat
with the severity of pruning. Usual planting distances recommended for
the apple on good fertile soils are 30 to 35 feet.7

Planting. — Where the soil has previously been well prepared the holes
for the tree need not be larger or deeper than is necessary to accommo-
date the roots in their natural position.

Setting the tree at the proper depth and compacting the soil well
around the roots are important considerations. Nursery trees usually
form their roots at a depth most congenial for their development and
when set in the orchard should stand at approximately the same depth
as in the nursery. This depth can generally be determined from the ap-
pearance of the tree trunk.

7 For a fuller discussion of planting distances and methods of thinning see : Allen,
F. W. Planting and thinning distances for deciduous fruit trees. California Agr.
Exp. Sta. Bul. 414:1-29. 1926. (Out of print.)

30 University of California — Experiment Station

To avoid air pockets, well-pulverized soil should be placed next to the
tree roots and tramped thoroughly as it is thrown in. All injured roots
had best be removed before setting. To facilitate planting, the remainder
may be shortened back to 6 or 8 inches. Cutting back is considered prefer-
able to bending out of their natural position. Small, fibrous roots, usually
dead before the tree is set, may likewise be removed, for they make it
difficult to place the soil in firm contact with the larger roots.

As the newly transplanted tree requires some time to become estab-
lished and as new root growth should precede that of the branches, trees
may profitably be planted as early in the season as mature nursery stock
can be secured and the soil can be put in good condition. "Where condi-
tions are favorable in late November and in December, trees set at this
time should have considerable advantage over those not planted until
March or April. At some of the higher altitudes, however, planting must
often be delayed until relatively late. Under such circumstances the
trees should be held as nearly dormant as possible so that the buds may
not push and utilize all the stored food before the growth of the roots.

As many of the feeding roots are cut in digging from the nursery, the
top of the tree should be correspondingly reduced. At the time of plant-
ing, therefore, the main stem is usually cut back to a height desired for
the scaffold branches. Immediately after planting, the entire stem
should be protected from sunburn and borers with a coat of whitewash.
A good whitewash may be made as follows : quicklime, 5 pounds ; salt,
% pound ; sulfur, *4 pound. Add the salt and sulfur while the lime is
slaking. Allow the whitewash to age several days before use, and dilute
to a buttermilk consistency. A whitewash that sticks somewhat better
but is more expensive is made from whiting, 6 pounds ; casein spreader,
1 pound ; and raw linseed oil, % pint.

Subsequent Care of Young Trees. — As previously mentioned, young
trees should get a good start and be kept growing vigorously during the
first season. Weed growth around the trunk should not compete with the
young tree for soil moisture unless there is frequent irrigation. If tree
protectors are used instead of whitewash against sunburn, the young
trees should be inspected several times to see that these do not interfere
with the formation of the scaffold branches at the desired locations.
After the new growth starts, better spacing and growth of the main
shoots may be obtained by selecting these in the most desirable locations
and removing or pinching back the others. (See section on pruning.) In
addition, the tree should be kept free from all diseases and insect pests
that may interfere with its normal growth.

Bul.425] Apple Growing 31

CULTURAL OPERATIONS IN THE ORCHARD

Cultivation. — As recent experiments have shown, the frequent and deep
tillage of most western apple orchards does not seem justifiable ; and the
claim that intensive cultivation conserves soil moisture, aids soil aeration
in the root zone, and increases yields is erroneous. Cultivation has there-
fore become less frequent and shallower.

Some cultivation, however, is recommended in most orchards : "It
serves to remove noxious weeds and weed competition ; to facilitate sub-
sequent operations such as irrigation, harvesting, brush removal, and
spraying ; to incorporate covercrops and manures ; to prepare the soil
as a seed bed for covercrops ; to facilitate the control of certain pests ;
and to aid in the absorption of water where tillage or other orchard oper-
ations have produced an air-impervious condition of the soil."8

Except on steep slopes in the foothill and mountain sections where
danger of soil erosion demands that the orchards remain in sod, most
apple orchards of California are maintained under a system of clean
cultivation or of cultivation and covercrops.

The exact time of the first spring cultivation depends upon the condi-
tion of the soil, the amount and season of rainfall or irrigation, and the
amount of covercrop and weed growth present. Tillage of wet soil is
never desirable. The surface should be relatively dry. Many of the
heavier apple soils must be worked at just the right time ; tilling either
too wet or too dry results in a hard, lumpy soil, often for the remainder of
the season.

In nonirrigated orchards grown under limited rainfall, the covercrop
should be disked down or turned under before the soil moisture is re-
duced to a point where the covercrop is competing with the trees. With
late spring rains or in irrigated orchards, this operation may be delayed
somewhat longer, and a heavier covercrop growth secured.

Shallow disking (fig. 4) is not only less expensive than deeper plow-
ing, but preferable. Disking in both directions of the tree rows in the
spring should be sufficient to kill the covercrop or weed growth and to
incorporate most of it into the soil. Since cultivation in the absence of
weeds has no influence in conserving soil moisture, the frequency of sub-
sequent tillage during the summer will depend largely upon the amount
of weed growth and the frequency of irrigations or of late spring rains. If
rains occur and the soil has become too compact to permit the construc-
tion of irrigation furrows or levees (in orchards which are irrigated)

8 Veihmeyer, F. J., and A. H. Hendriekson. Essentials of irrigation and cultivation
of orchards. California Agr. Ext. Cir. 50:1-24. Eev. ed. 1936.

32 University of California — Experiment Station

or if there is a resumption of heavy weed growth, a second cultivation
may be necessary before irrigating. But as a rule this is unnecessary;
hence the second cultivation follows any irrigation given, or it may even
be withheld until the irrigation levees must be broken down to facilitate
harvesting, spraying, pruning, and brush removal or until a seed bed
must be prepared for sowing the covercrop.

Intercropping. — Intercropping is a possible source of income to the
orchardist during the first few years. This practice, however, after the

*** mM

k

^S

W&*l3sm

W *9S JJL TBk.

Fig. 4. — Section of orchard disk equipped with depth regulators.
The soil is cultivated to a depth of only 4 inches when the disks are
set for a full cut.

first two or three seasons really becomes double cropping, in that soil
fertility and moisture removed by the intercrop are, in some instances,
needed for the best growth of the trees. As a rule, intercrops are most
successful on fertile soils and on land under irrigation.

Cultivated crops are recommended for young orchards, and annual
crops are considered somewhat more desirable than perennial. Among
the most desirable, where a market is established, are beans, squash,
melons, cabbage, turnips, mangels, potatoes, spinach, beets, peas, toma-
toes, and rhubarb. Lettuce is perhaps now the leading intercrop for any
young plantings in the Pajaro Valley. Strawberries are also grown.
Bush fruits were previously very popular in the Sebastopol area. Since
nursery stock, corn, and other grains compete with the trees more than
do other crops, their growth is to be discouraged.

Covercrops. — A covercrop offers the most feasible means of maintain-

BuL- 4251 Apple Growing 33

ing the organic matter in the soil, and either a seeded crop or one of
natural growth is to be found during the winter season in most culti-
vated apple orchards. The amount of growth secured from covercrops
depends upon the soil, the water supply, and the temperature during the
growing season. In Sonoma County a satisfactory natural growth of
white and red-stem filaree (Er odium maschatum and Er odium cicuta-
rium), mustard, bur clover, and miner's lettuce usually results from the
fall application of manures. Little seeding of covercrops is done. In the
Pajaro Valley there are both natural covercrops and those which are
sown. As in Sonoma County, manure, applied in the fall, or commercial
fertilizer increases growth. To obtain a good growth before the end of
the growing season, covercrops may be sown in irrigated sections in
August. In nonirrigated sections, little if any advantage is gained by
seeding before the fall rains begin. Drilling in the seed is preferred to
broadcasting, as the depth of the planting can thus be regulated and a
more even stand secured. Although they may vary slightly in different
sections, the following rates of seeding are recommended : field peas, per
acre, 60-80 pounds ; vetch and horse beans, 40-50 pounds ; melilotus, 25
pounds, or if scarified, 15 pounds ; bur clover and cereals (where planted
with legumes), 20 pounds; cereals planted alone, 50-60 pounds.

Either leguminous or nonleguminous crops may be planted, but where
the former make satisfactory growth they have the advantage of adding
nitrogen to such soils as need it. Among the leading legume crops grown
in California are the common vetch (Vicia sativa), purple vetch (Vicia
atropurpurea) , bitter clover (Melilotus indica), Canada field peas (Pi-
sum arvense), bur clover (Medicago hispida), and horse bean (Vicia
faba). As covercrops in apple orchards, the vetches and clovers are
usually the most widely grown. Vetch is recommended in the coast coun-
ties and south of the Tehachapi. Bur clover does well in most parts of
the state, usually reseeding itself year after year if soil fertility is main-
tained. As a rule, however, it fails to produce such heavy growth as the
vetches or bitter clover. The grains — barley, rye, and oats — and the
mustards are the most commonly grown nonleguminous plants. The cul-
tivated mustard {Brassica alba) is popular in the Watsonville district
(fig. 5).

When one has unlimited irrigation facilities and a soil sufficiently
rich in available nitrogen to grow two crops simultaneously, summer
crops such as cowpeas, soybeans, sweet clover, and its variety, Hubam
clover, are sometimes grown. Red clover also seems adapted to the foot-
hills of the Sacramento Valley and may become fairly important in the
northwestern coast counties. Alfalfa is a permanent crop, now generally

34

University of California — Experiment Station

used in the irrigated apple sections of Washington and Oregon and
grown to a limited extent in this state.

As stated under the section on cultivation, unless the covercrop is
becoming excessively heavy, it should be allowed to grow as late in the
spring as is consistent with maintaining good soil moisture.

With a supply of irrigation water, the crop can both be started earlier
in the fall and allowed to grow later in the spring. The greater the growth
and the more nearly the crop can be allowed to approach maturity, the

'•s^fV y.;

Fig. 5. — An excellent covercrop of mustard in a Pajaro Valley orchard.

greater will be the amount of organic matter derived from it. Covercrops
should produce from 10 to 30 tons of green material per acre. Legume
crops may contain from 10 to 13 pounds of nitrogen per ton of material.
Little if any beneficial effect is usually evident from the use of either
manures or covercrops until the second season.

Animal Manures. — Since manures add nitrogen and at the same time
improve the physical condition of the soil, they have long been recom-
mended. At present, however, their scarcity limits their use. When the
cost is not prohibitive, applications of ordinary barnyard manure may
be made at the rate of 6 to 10 tons to the acre. Poultry manure, largely
used by Sebastopol growers, is usually applied in quantities of 2 to 3
tons to the acre. Applications are generally made in the dormant season.
In fertilizing mature trees, the manure should be scattered well between
the rows rather than immediately adjacent to the tree trunk.

Bul. 425] Apple Growing 35

Commercial Fertilizers. — The application of commercial fertilizers to
orchard soils has definitely improved the growth of the covercrop and,
according to some, the growth of the trees and the fruit. Nitrogenous
fertilizers such as ammonium sulfate, ammonium phosphate, and cal-
cium nitrate have given best results. The usual rate of application recom-
mended is 2 to 3 pounds per tree for young trees and from 4 to 6 pounds
for those of bearing age. If only one application is made, it had best be
scattered over the surface of soil under the branches just before the
spring disking. In some instances dividing this application and applying
half the amount the previous fall has given a greater covercrop yield.

Irrigation. — Where bearing trees will produce 8 to 10 inches of new
wood each year and a satisfactory annual crop of good-sized fruit, irri-
gation would seem unnecessary. If, however, wood growth is scanty and
the fruit, even when properly thinned, fails to size properly and is of
poor quality, lacking in crispness and flavor, irrigation should be con-
sidered. The success of many orchards will largely depend upon whether
the owner can supply water during the growing season. In other in-
stances the water is probably being applied uselessly.

The essentials in connection with the irrigation of orchards have been
fully covered in a previous publication.9 A supply of available moisture
throughout the growing season is the condition desired, and frequent
examination with a soil auger is the most satisfactory method of deter-
mining the necessity for and the frequency of irrigation.

Sufficient water should be applied to secure thrifty but not excessive
or rank wood growth. Light, sandy soils or soils underlain with a sub-
stratum of gravel may require frequent applications, while the heavier
clay loams may need only one or two. The latter is the usual practice in
the irrigated orchards of the more important districts. Type of soil,
topography, the amount of water available, and the cost will determine
the most satisfactory way of applying water. The chief essentials, how-
ever, are even distribution and good penetration. The most common
methods are the contour-check system of flooding and the furrow sys-
tem, in Avhich six to eight large furrows 6 inches or more in depth are
made between each two rows of trees. Contour furrows are best adapted
to foothill and mountain sections.

Thinning. — The value of fruit thinning is now well recognized and in
years of heavy crop yields is one of the most important orchard opera-
tions. Removing the surplus specimens aids in increasing the size, color,
quality, and uniformity of the fruit, prevents breaking of limbs, assists

9 Veihmeyer, F. J., and A. H. Hendrickson. Essentials of irrigation and cultiva-
tion of orchards. California Agr. Ext. Cir. 50:1-24. Eev. ed. 1936.

36 University of California — Experiment Station

in maintaining the general vigor of the trees, makes spraying more effec-
tive, and decreases the labor of handling the crop at harvest time.

In general, thinning should be practiced sufficiently to produce at
least moderate-sized fruit and relieve the overburdened trees. Since the
food supply of the fruit is elaborated in the leaves, the size of the fruit
is materially influenced by the ratio between the number of leaves (or
total leaf surface) on the tree and the number of fruits. For certain
important varieties, 40 to 50 leaves per fruit seems most desirable.10 To
determine the exact number of fruits and leaves on a full-bearing tree
(60,000-100,000 leaves on a tree) is, however, obviously impracticable;
hence actual thinning recommendations are still based on spacing the
fruits at certain distances. A distance of 6-8 inches apart is generally
satisfactory. Another method is to remove enough specimens so that
when the fruits attain their full size they will be 4 to 6 inches apart on
the branch. Unless the set of fruit is very uneven, clusters should be
thinned to one apple each.

No definite dates can be given for thinning, because they vary with the
variety, the season, and general climatic conditions. In most instances,
however, a natural drop of young fruits occurs several weeks after the
blossoming period. Immediately thereafter, while the apples are still
small and before the seeds develop to any extent, the surplus fruits had
best be removed.

Bracing and Propping. — Well-pruned and well-thinned trees should
need relatively little bracing or propping. In many instances, however,
because of weak crotches, extra long horizontal limbs, and light or no
thinning, considerable damage may occur. For open-centered trees or
others whose main branches are structurally weak, the central wire-
bracing system, with wires running from screw eyes or staples in the
branches to a ring in the center of the tree, may be used to good advan-
tage. This type of bracing is permanent except for repairing broken or
tightening loose wires.

In most apple orchards, however, where smaller outside limbs are
most in need of support, wooden props are used. Naturally these must
be placed each season and taken down again at harvest time.

Frost Protection. — Since the larger apple sections of the state are at
low altitudes and relatively near the coast, frost danger to the blossoms
or young fruit is infrequent, and few growers are prepared to heat their
orchards. At altitudes of 4,000 feet or higher, spring frosts may do con-
siderable damage or even destroy the crop one year out of four or five.

10 Magness, J. E., F. L. Overley, and W. A. Luce. Eelation of foliage to fruit size
and quality in apples and pears. Washington Agr. Exp. Sta. Bui. 249:1-26. 1931.

Bul. 425] Apple Growing 37

Even under these conditions, however, the returns from the crop lost
would probably not justify the necessary investment in fuel, storage
tanks, wagons, heaters, thermometers, and other equipment that would
be of little or no use in most years.

PRUNING

Young trees are usually trained to one of two systems : the open-center or
vase-shaped tree ; or the modified leader, sometimes called delayed open-
center type. With the open-center system of training, three branches are
preferably chosen to form the framework. These are all pruned to main-
tain an equal size as nearly as possible. Any tendency of a branch to out-
grow the others and assume the lead is suppressed. The advantages at-
tributed to this system of training are that it forms an open, spreading,
low-headed tree, producing highly colored fruits. The principal objec-
tion or disadvantage is that the scaffold branches tend to issue from one
point, and thus produce a tree structurally weak (fig. 6) .

The modified leader or delayed open-center tree results, as the name
would indicate, from a system of training intermediate between the
open-center and the central-leader type of tree grown in the eastern
states. It is started by letting the topmost branch assume the lead for
two to five years. Thus one obtains greater spacing of the scaffolds on
the trunk, secures strong crotches, and at the same time keeps the tree
relatively close to the ground. Apparently this type has much in its
favor and should be grown to a greater extent.

Starting the Main Branches. — The height of the trunk is determined
when the tree is first headed. The main stem should be left high enough
so that approximately 6 inches will intervene between the main scaffolds
and yet the lowest branch will not be too near the ground. A height of
24 to 30 inches is recommended. As a rule, only three main branches well
distributed around the trunk as well as up and down are desired. Ob-
servations show that at 5 feet from the ground five to seven secondary
stems are usually all that the bearing tree can carry without crowding
(fig. 7). If young trees are already branched when planted, the side
branches suitably located may be only shortened, rather than cut off.
All superfluous branches, however, should be removed.

First Summer's Pinching. — Where young trees grow vigorously the
first season, summer pinching of the surplus shoots when 3 or 4 inches
long is sometimes practiced. Such pinching, done at this time, results in
more vigorous growth of the branches selected to form the main frame-
work, in better-shaped trees, and in less cutting at the first winter prun-
ing. Sometimes the trees should be gone over again in about six weeks to

38

University of California — Experiment Station

suppress any new undesirable growth that may have started after the
first pinching.

First Dormant Pruning. — At the first dormant pruning, which in
California may be given any time after leaf fall and the beginning of

Fig. 6. — Four-year-old Red Astrachan tree after pruning.
Branches thinned only. The two lowest branches make a poor
crotch, due to low heading and poor training the first year.

activity in the spring, the scaffold branches should be headed back 15
to 30 inches or more from the juncture with the tree trunk. As the pri-
mary reason for this heading is to induce more branching, the limbs
should be cut at the approximate height where the second branches are

Bul. 425]

Apple Growing

39

desired. To secure the modified-leader type of tree, head back the upper-
most branch very lightly. Where the variety naturally makes a spread-
ing growth, head the branches somewhat severely, cutting to an inside
bud. "Where the growth is upright and a greater spread is desired, cut to
an outside bud.

The first dormant pruning is of great importance because the tree is
being shaped as it should grow. The severity of pruning will also have a
marked effect upon the age at which the tree will come into bearing.

Fig. 7. — Close view of bearing tree showing crowding of main branches.

Second Summer's Pruning. — From the main scaffold branches chosen
and headed back at the first dormant pruning, numerous shoots are apt
to start. Some of these, if not suppressed, may outgrow those desired for
secondary branches. The tree may also become so filled with new wood
that severe thinning will be needed the following winter. It may be ad-
vantageous, therefore, to go over the trees early in the second summer
when the new shoots have attained a length of 6 to 10 inches and pinch
back all undesirable growth. If the desired number of well-spaced scaf-
fold branches were secured at the last pruning, two shoots from each of
these will be sufficient to leave. If even distribution was not obtained,
one or more additional shoots well placed may fill a vacancy and produce
a better-balanced tree.

40 University of California — Experiment Station

Second Dormant Pruning. — Where the trees are summer-pruned as
outlined above, the second dormant pruning should usually consist only
of thinning out superfluous, interfering, and misplaced branches. Such
a variety as Spitzenburg (fig. 8) may necessitate heading of the sec-
ondary branches to induce further branching at the desired height. With
most varieties, however, this practice is not necessary and means addi-
tional pruning later on, with consequent delay in the time required for
the tree to reach commercial production. Any extra-long or overvigorous

-Five-year-old Spitzenburg tree showing long, rangy growth of
branches. Note excellent set of fruit spurs.

branch growing at the expense of the others or destroying balance should
be subdued by heading. Heavy or severe cutting will check the growth
of any branch, whereas light pruning or none at all will encourage most
rapid development.

Third and Fourth Dormant Pruning. — Pruning during the third and
fourth years is largely a continuation of that given the second year. Con-
tinue to thin out unnecessary and interfering branches, water-sprout
growth, and perhaps some small branches near the ground that hinder
cultivation. Keep the center of the tree open to sunlight ; yet avoid prun-
ing the limbs up "clean" by removing all the short branches that should
naturally develop into fruiting wood.

Pruning Bearing Trees. — Trees properly cared for during their form-
ative period should be well shaped and mechanically able to support

Bul. 425"

Apple Growing

41

heavy loads. Although some varieties, such as Rome Beauty, Jonathan,
and Wagener, produce much of their fruit on the tips of last year's
branches and although on the Pacific Coast a number of varieties may
produce fruit laterally on one-year twigs, most of the crop is produced
terminally on short branches or on spurs originating from wood two

Fig. 9. — Typical pruning of a full-bearing Gravenstein apple tree in a
Sebastopol orchard.

years old or older. These spurs normally begin to form after three to five
years, or when the young tree naturally tends to slacken its vegetative
growth.

The primary consideration, therefore, in pruning bearing trees is to
maintain a proper balance betAveen vegetative growth and fruit produc-
tion. Excessive growth by the young tree is usually produced at the
expense of fruit production, while overbearing is accompanied by less
growth and if continued may destroy vigor. The ideal condition during
the years of maturity is for the trees to make 6 to 10 inches of new growth

42

University of California — Experiment Station

-Typical Yellow Newtown trees in a Pajaro Valley orchard, illus-
trating the general type of pruning used and something of the fruiting area of
the tree. Note growth of the horse-bean covercrop.

fif ?s$

IK, f i
Mf 1 f\ I

PI

| //

|1

, . ., ,.,„r ...... ,..^- -,

Fig. 11. — Typical Yellow Bellflower orchard in the Pajaro Valley. The trees
show the result of heavy crop production. Props from the previous year still
remain in the orchard.

Bul. 425] Apple Growing 43

each year, and thus increase and maintain the fruiting area while pro-
ducing large but not excessive annual crops.

With most varieties that previously have received regular pruning,
there is little necessity for more than a light annual thinning. The
center of the tree should be kept fairly open. Trees attaining too great a
height may be lowered by cutting back some of the larger upright
branches to strong laterals (fig. 9). Light crops and a large amount of
vegetative growth would indicate that previous pruning practices had
been too severe. Such trees should receive very little dormant pruning.

Pruning Old Trees. — Old bearing trees, producing heavy crops of
small-sized fruit, or those not making 6 to 8 inches of new wood growth
annually, require somewhat heavier pruning than younger trees in
order to secure the desirable amount of new growth and to maintain the
vigor of the fruiting spurs. Moderately heavy thinning of the smaller
branches also reduces the amount of fruit thinning necessary in years of
heavy production. Figures 10 and 11 illustrate the appearance of typical
Yellow Newtown and Yellow Bellflower trees in the Pajaro Valley.

Treatment of Pruning Wounds. — Whenever one must remove limbs
larger than an inch or so in diameter, he should protect the pruning
wounds with some covering in order to exclude rot-causing fungi. For
this purpose commercial preparations may be used. Bordeaux paste is
also employed by some growers in the Pajaro Valley. In recent years a
more nearly permanent covering, bordeaux powder combined with paint,
has given good results. An excellent formula is :

1 gallon paint (formula similar to Fuller's "contour" paint)

1% gallons boiled linseed oil

7 pounds of bordeaux powder ("one-package" bordeaux)

APPLE DISEASES AND THEIR CONTROL11

The apple, like most other plants, is subject to infectious diseases caused
by fungi, bacteria, and viruses ; and to noninfectious disorders, usually
due to unfavorable action of soil or weather. The fungus and noninfec-
tious diseases discussed here include most of those known to be important
with respect to apples, in this state.

Powdery Mildew. — The principal foliage disease of apples in Califor-
nia is powdery mildew, caused by the fungus Podosphaera leucotricha,
and is particularly prevalent in the Pajaro Valley. A superficial white
powdery fungus growth appears on leaves, shoots, and sometimes fruits,
and dwarfs and distorts the leaves and shoots if they become affected
early.

11 This section and that part of table 2 which deals with diseases were contributed
by H. Earl Thomas, Associate Plant Pathologist in the Experiment Station.

44 University of California — Experiment Station

Since the fungus hibernates in buds, especially terminal buds, mil-
dewed shoots should be removed at pruning time. The principal control
measure consists in spraying at the cluster-bud stage with 2 gallons of
liquid lime-sulfur or 5 to 10 pounds of wettable sulfur to 100 gallons of
water and again with the wettable sulfur at the calyx period. If mildew
has been permitted to accumulate in the orchard, two or three years may
be required to bring the disease under control.

Scab. — Scab, caused by Venturia inaequalis, is occasionally important
where rainy weather continues after growth of the tree is under way.
Superficial velvety dark-olive to black spots are formed on fruits and
leaves. The tissues beneath the scab spots are often dwarfed, resulting in
misshapen fruits. Older scab spots from which the fungus has weathered
away have a russeted appearance.

In most cases two spray applications at the cluster-bud and calyx
stages should control the disease. Orchards heavily infested may need
an early application when the leaves of the flower buds are about V2 inch
long. Either lime-sulfur (1-50) or bordeaux mixture 3-3-50 is effective
if fortunately timed. The latter material is more apt to russet the fruit.

Root Rot. — In the root rot, caused by Armillaria mellea, trees are
killed slowly and usually from the center outward in a rather definite
area in the orchard. This fungus (often also called oak root fungus)
spreads through the roots and crowns, producing characteristic whitish,
fan-shaped mycelial mats within and just beneath the bark. Since the
apple is less susceptible than certain other of the fruit trees, the progress
of the disease may be considerably delayed (though not stopped) by
removing the soil from the crowns and larger roots of slightly affected
trees and leaving these exposed during the dry season. Some benefit may
also result from cutting off affected roots and bark of trees in the initial
stages of the disease. Wounds made in this operation should be covered
with a fungicide such as mercuric bichloride (1 part in 1,000 parts of 25
per cent denatured ethyl alcohol in water) .

A root rot similar in appearance but caused by a different fungus,
Rosellinia necatrix, has been found in a number of orchards. This may
sometimes be distinguished from Armillaria root rot by the absence of
well-defined fan-shaped mats in the bark and by the presence of loose
cottony wefts of fungus mycelium in the moist soil around infected roots.
A laboratory test is often necessary, however, to separate these diseases
with certainty. No satisfactory control is known.

Crown Gall, Hairy Root, or Woolly Knot. — In this disease, irregular,
rather spongy tumors occur on the crowns and roots, with or without an
excessive development of fine fibrous roots. The causal organism is Bac-

Bul. 425] Apple Growing 45

terium (Phytomonas) tumefaciens. The most destructive form originates
in the nursery, often at the graft union. The apple is less affected than
certain other fruit trees, notably the peach, and is usually not severely
injured in the orchard.

One should, however, plant only trees with vigorous roots and smooth
graft unions free from visible tumors. Galls that appear on the crowns
in the orchard may be cut off with a chisel, and the wounds covered with
bordeaux paste. This treatment aids in preventing the entrance of other
disease organisms into the tree through the old galls.

Fire Blight.12 — Blight, caused by Bacillus (Erwinia) amylovorus, af-
fects all parts of the apple as is the case with the pear, cotoneaster,
loquat, pyracantha, quince, and toyon. The bacteria overwinter in dis-
eased bark and usually invade the tree through the blossoms. Less fre-
quently they enter through the young shoots and cause these to wither
and turn brown. The bacteria form cankers (dead areas in the bark)
on larger branches, trunks, and roots around the bases of blighted fruit
spurs and shoots. A milky or brownish sticky fluid often oozes from
diseased parts.

The disease is favored by warm, humid weather, especially at blossom-
ing time, and by vigorous growth.

The blossoms, shoots, and many of the roots of commercial varieties
are highly susceptible ; but varieties differ widely in the susceptibility of
the trunks and larger branches. In this regard Alexander, Spitzenburg,
and Tompkins King are highly susceptible; Jonathan and Wagener
moderately so ; Delicious, Gravenstein, Rome Beauty, Stayman Wine-
sap, Winter Banana, Yellow Bellflower, and Yellow Newtown com-
paratively resistant.

Control in apple trees resembles that in pear, the main feature con-
sisting in removing all infections as far as possible, during the dormant
season. The smaller affected branches are cut off. Cankers on larger
branches are cut out down to the wood, including a zone of live bark on
all sides 2 to 3 inches wide. With more susceptible varieties, the new in-
fections should be removed in the spring soon after blossoming time.
A close watch should always be kept for the blight that may develop in
roots and crowns through infection of root suckers. Wounds from blight-
eradication work should be treated with a good germicide such as is
made by dissolving 1 part of mercuric chloride and 1 part mercuric
cyanide in 500 parts of a solvent consisting of 10 per cent glycerine in
water. This solution is a deadly poison.

12 For more complete information see : Thomas, H. Earl, and P. A. Ark. Fire blight
of pears and related plants. California Agr. Exp. Sta. Bul. 586:1-44. 1934.

46 University of California — Experiment Station

Dieback. — Several types of injury to the root system or other parts of
the tree may be followed by dying-back of terminal shoots and branches.
A seemingly small part of the dieback in the state is associated with little-
leaf or rosette (which see), and another part is directly related to poor
drainage. Some dieback, however, not clearly related to these conditions,
is sometimes found in the Sebastopol area. The buds fail to start or
die soon after growth has begun, and the shoots die from the tips down-
ward. In severe cases the bark of larger branches and trunks breaks
down, sometimes with a sour odor. Although the trunks and larger roots
are usually sound in appearance, many of the fine feeding roots are
dwarfed or killed outright. This type of injury is almost never found in
areas amply supplied with the clay subsoil characteristic of the district.
Rather it seems related to the types of subsoils containing little clay but
sometimes containing cemented layers (more or less impervious to water)
or sandstone bedrock near the surface.

Careful selection of orchard sites and drainage of obviously wet areas
are suggested. In the Sebastopol area, repeated covercropping is appar-
ently of value in this connection.

Sappy Bark. — In the condition known as sappy bark, caused by the
fungus Polystictus versicolor, the bark is soft and spongy during wet
weather, loose and papery in dry weather ; and the wood beneath breaks
down with a punky rot. In vigorous trees the heartwood may rot exten-
sively, with little or no evidence in the bark until later stages. Usually
the leathery, bracket-type fruiting bodies of the fungus appear even-
tually on dead bark or wood.

The prevention of this disease requires the continuous protection of
unhealed wounds. Bordeaux paste is a good fungicide in this connection,
though it involves more frequent renewal than certain other materials.
Careful pruning early in the life of the trees will later obviate the neces-
sity for large pruning wounds.

Little-Leaf or Rosette. — Although apples are highly susceptible to
little-leaf, most of them in the state are grown in districts where the dis-
ease is not prevalent. In mild cases the shoot toward the tip produces
leaves progressively smaller, paler, and closer together, giving in the
end the appearance of a tuft or rosette. The tip of the shoot is often
distinctly thickened. In severe cases the shoots and branches may die
back or may survive with little or no terminal growth, the buds develop-
ing slowly and the leaves remaining small and narrow.

Affected trees may be cured by zinc applied in any of several different
ways. The most satisfactory method has proved to be spraying during
the dormant season with 25 pounds of zinc sulfate in 100 gallons of water.

Bul. 425] Apple Growing 47

Other Noninfectious Diseases. — For other noninfectious diseases, in-
cluding bitter pit, internal browning, scald, and other similar troubles
affecting the fruit, see the section on storage troubles.

INSECT PESTS AND THEIR CONTROL13- 14

The most important insect pests of the apple in California are the codling
moth, scale insects, and aphids. Other insect pests occur only in certain
localities or at certain seasons.

Codling Moth. — The codling moth (Carpocapsa pomonella) undoubt-
edly causes the greatest loss of all insect pests to apple growers through-
out the state and demands a complete spray program properly timed.
The attendant problem of spray residue necessitates careful planning of
spray applications. Practically all programs require some efficient means
of removing the spray residue to meet the tolerance requirements (p. 56) .
There are two definite broods of this moth each season : the first, from
March to June ; the second, from July to October. Effective control of the
first brood is most important ; it eliminates not only the so-called "calyx-
worms" at harvest but also the possibility of small "side" worms of the
second brood. This is best accomplished by using the proper dosage and
timing in the calyx spray and in the first two cover sprays. The calyx
spray should be applied when approximately two-thirds of the petals
have fallen ; the first cover spray 10 to 14 days later. The dosage for these
first two sprays is as follows :

Powdered standard lead arsenate 4 pounds

Fluxit-type spreader y2 pound

Water 100 gallons

Subsequent cover sprays are best timed with the codling-moth bait-
trap emergence records ;15 but in the absence of such records applications
at three-week intervals, repeated as often as necessary, have proved sat-
isfactory. The dosage for these cover sprays should be as follows :

Powdered standard lead arsenate 3 pounds

Fluxit-type spreader y2 pound

Water 100 gallons

No substitute for standard lead arsenate thus far tried has proved
satisfactory.

Besides spray control one should give special attention to orchard

13 This section and that part of table 2 which deals with insect pests were contrib-
uted by A. D. Borden, Assistant Entomologist in the Experiment Station.

"For additional information on insect pests and their control see: Essig, E. O.,
and W. M. Hoskins. Insects and other pests attacking agricultural crops. California
Agr. Ext. Cir. 87:1-155. 1934.

15 Borden, Arthur D. Codling-moth bait traps. California Agr. Ext. Cir. 63:1-13.
1932.

48 University of California — Experiment Station

sanitation, which includes thinning out infested fruit, destroying wind-
falls and culls, banding to kill overwintering larvae, and general orchard
and packing-house sanitation.

Scale Insects. — The well-known San Jose scale (Aspidiotus pernicio-
sus) is a small, circular, cone-shaped gray scale and causes a character-
istic red or purplish stain on the bark and fruit. For control, spray in
full dormant period with lime-sulfur solution (1-10) ; or with tank-mix16
oil of winter grade (3-100) ; or with commercial winter oil emulsion
(5-100).

The oyster-shell scale (Lepidosaphes ulmi) resembles a miniature
oyster encrusted on the trunk or small limb, is light to very dark brown
in color, and overwinters largely in the egg stage. For control, spray in
full dormant period with lime-sulfur solution (1-8) ; or with tank-mix
oil of winter grade (4-100) ; or with commercial oil emulsion (6-100),
plus 3 gallons lime-sulfur solution to each 100 gallons of spray.

The soft-scale insects known as mealybugs {Pseudo coccus maritimus)
may infest all parts of the tree and excrete quantities of honey dew, caus-
ing a smutty appearance of fruit and foliage. The mature insects are
flattened, oval, soft-bodied, and covered with a powdery wax that ex-
tends from the sides in a series of short filaments. The oval, pale-yellow
eggs are deposited in a cottony mass. For control, spray in full dormant
period with a combination spray made according to the following for-
mula :

Dormant commercial oil emulsion or tank-mix dormant oil

emulsion 4-100 5 gallons

Commercial lime-sulfur solution 3 gallons

Water to make 100 gallons

For control in spring and summer, spray every few weeks with commer-
cial summer oil emulsion (2 to 3 per cent) or with tank-mix foliage oil
spray (1% to 2 per cent) .

For control of the greedy scale and the brown apricot scale, spray in
full dormant period with dormant tank-mix oil (3-100) or with dormant
commercial oil emulsion (4-100).

Aphids. — The rosy apple aphid (Anur -aphis roseus) and the green
apple aphid (Aphis pomi) are distinguished by their color, the char-
acteristic curling of the leaves, and the stunting of the young fruits. They
overwinter in the egg stage, the eggs having been deposited in the late
fall on the fruit spurs and buds. For controlling the egg a new spray
material known as coal-tar distillate emulsion has proved very effective.
It should be applied in the full dormant period at a concentration of 2%

18 Borden, Arthur D. The tank-mixture for dormant oil spraying of deciduous
fruit trees in California. California Agr. Exp. Sta. Bui. 579:1-20. 1934.

Bul. 425] Apple Growing 49

per cent actual creosote oil per 100 gallons of water. This material, being
very caustic, must be handled with care.

For controlling hatched insects the addition of nicotine sulfate (Black
Leaf 40, % pint to 100 gallons of spray) to the cluster-bud and calyx
sprays is often advisable if temperature conditions are favorable. Hand-
picking of infested fruit and leaf spurs is often practiced.

The woolly apple aphid (Eriosoma lanigera) has a reddish body, com-
pletely covered with white woolly wax. It infests both root system and
aerial parts of the tree, causing characteristic nodule swellings of the
roots and twigs and smutting of fruit and foliage.

To control the root infestations use paradichlorobenzene during the
fall. For overwintering aphids on the tree, spray in full-dormant period
with 3 per cent dormant oil emulsions under high pressure. For summer
infestations of fruit and foliage, spray with the following solution :

Liquid whale-oil soap 1% gallons

Nicotine sulfate % pint

Water to make 100 gallons

Fruit Tree Leaf Roller. — The pest known as the fruit tree leaf roller
(Ar chips argyrospila) attacks foliage and young fruit soon after the
buds open in the spring, tying leaf clusters together and feeding on im-
mature fruit and foliage. The caterpillars are difficult to control after
they have rolled the leaves together. Oil emulsions applied in the full
dormant period will destroy the egg masses usually found on the higher
branches of the tree. Use tank-mix dormant oil (4-100) or commercial
dormant oil emulsion (7 or 8 gallons to 100) .

Tussock Moth. — The brilliantly colored caterpillars of the tussock
moth (H emer ocampa vetusta), clothed with tufts of black and white
hair, are more commonly known as horned caterpillars. The grayish-
white, felty egg masses are found, during the winter, on the trunk and
limbs where wingless female moths deposited them in late summer
and fall.

Hand-picking and destruction of the egg masses in winter and tangle-
foot banding of the tree trunks in the spring give the most efficient con-
trol. Poisonous sprays are of little value except in the very early spring.

Skin Worm. — The skin worm (Cacaecia franciscana) , often a serious
pest on apples in the coastal areas, feeds on the skin of the fruit at points
of contact, and at the stem and blossom ends. It overwinters as larvae
and pupae, the adult emerging and depositing egg masses on trunks,
main limbs, and foliage from before the time of bloom until late summer.
Best control is obtained by destroying the egg masses. An early applica-
tion of 2Vs per cent lime-sulfur solution or 2 per cent winter oil emulsion

50 University of California — Experiment Station

on the trunk and main limbs will destroy the egg masses before blossom-
ing time. Two or three applications of summer-type oil emulsion (2
gallons to 100) on foliage and fruit at intervals of three weeks after
blossoming will destroy later broods. Usually about three applications
are sufficient.

Pandemis. — The pandemis insect (Pandemis pyrusana), often con-
fused with the fruit tree leaf roller, feeds on the leaves and fruit. It
overwinters as an immature larva and is controlled by spraying with
dormant oil emulsions (3 per cent) and nicotine sulfate (% pint to 100
gallons spray).

Tent Caterpillars. — Occasionally the coast tent caterpillar (Malacos-
oma pluvialis) and other species attack fruit trees. The compact nests
may be pruned out or torched. Spraying with arsenate of lead gives effec-
tive control.

Western Flat-headed Borer. — The beetle known as the western flat-
headed borer (Chrysobothris mali) deposits eggs in sunburned or other
dead areas of the trunk, and the larvae later burrow into the wood. Their
damage to two and three-year-old plantings is often serious. For control,
prevent sunburn by using tree protectors or whitewash the trunks and
dig out the borers.

Leafhopper. — Occasionally in the coastal areas the apple leafhopper
(Empoasca mali) not only damages the foliage, but also spots the fruit
with its excrement. Control measures should be directed against the
nymphs by spraying with nicotine-soap sprays or dusting with 5 per
cent dust.

Mites or Red Spiders. — The brown mite (Bryobia praetiosa), the
European red mite (Paratetranychus pilosus), and the common red
spider (Tetranychus telarius) often build up populations sufficient to
cause injury. The first and second species overwinter in the egg stage
and may be controlled with the usual dormant oil emulsion sprays. Sum-
mer infestations of any species may readily be controlled with the follow-
ing spray :

Liquid lime-sulfur solution 1 gallon

Wettable sulfur 5 pounds

Water to make 100 gallons

Summer-type oil emulsions (l1/^ gallons to 100) added to lead sprays
may be substituted when a combination spray is indicated.

SPRAY PROGRAM

Fortunately apple growers in any one section do not usually have to
combat all the diseases and insect pests previously mentioned. In some
sections certain of these may be almost unknown. On the other hand, one

Bul.425]

Apple Growing

51

TABLE 2

Spraying Schedule for Control of the Most Common Insects and Diseases

of the Apple

Time of application

Pest or disease

Spray materials and strength

San Jose scale and mite

Oyster-shell scale and

lute spray, by tank-mix method; or 5-6 gallons dor-
mant oil emulsion to make 100 gallons; or 10-12 gal-
lons lime-sulfur solution to make 100 gallons.

Dormant period
(January and Feb-
ruary) , before buds

Fruit tree leaf roller

spray, by tank-mix method; or 5 gallons dormant
oil emulsion to make 100 gallons, plus 3 gallons lime-
sulfur solution for each 100 gallons of spray. t

Green and rosy apple-

spray, by tank-mix method; or 7-8 gallons dormant
oil emulsion to make 100 gallons.

sote oil to each 100 gallons of dilute spray) .

1Yi gallons lime-sulfur solution to each 100 gallons of
spray solution; or 2 gallons dormant oil emulsion to
each 100 gallons of spray applied to trunk and main
limbs.

Delayed dormant
buds in green-tip

[Scab

spray solution.};

Cluster-bud stage
(before petals open)

Scab and powdery
mildew

Aphids (newly hatched)
Skin-worm eggs (second

2 gallons lime-sulfur solution to each 100 gallons of
spray solution or 5 to 10 pounds of wettable sulfur
to each 100 gallons of solution.

Add % pint nicotine sulfate to each 100 gallons of di-
lute spray in the above dosage.

2]/2 gallons of lime-sulfur solution to each 100 gallons of

spray solution — covering trunk and main limbs.

Calyx period when
two-thirds of petals
are off

Codling moth (calyx
spray) , scab, and mil-
dew

4 pounds standard lead arsenate per 100 gallons of
spray and 5 to 10 pounds wettable sulfur to each 100
gallons.

spray in the above formula.

First cover (10-14
days later)

Mildew (Sonoma Co.) . . .
Skin-worm eggs (third
spray)

3 to 5 pounds wettable sulfur per 100 gallons of spray.
See table footnote ^.

For footnotes, see end of table, next page.

52

University of California — Experiment Station

TABLE 2— (Concluded)

Spraying Schedule for Control of the Most Common Insects and Diseases

of the Apple

Time of application

Pest or disease

Spray materials and strength

Second cover, timed
by bait-trap catch,
or within 3 weeks . . .

Leaf hopper nymphs

of spray, with addition of a suitable spreader.

Add % pint of nicotine sulfate to the above lead spray ;
or dust with 5 per cent nicotine dust.

3 pounds of standard lead arsenate to each 100 gallons
of spray, with addition of a suitable spreader.

cessary, timed by
bait-trap catch

when necessary,
timed by bait-trap
catch

* Mite eggs are more effectively controlled by use of oil emulsions.

t Lime-sulfur solution is not compatible with all oil emulsions; it is compatible with tank-mix and
most paste-type emulsions.

X This application will be necessary only under severe scab conditions.

1 Applications of oil emulsions on foliage with sulfur present may cause defoliation. If skin-worm eggs
are still present, consult your county agent.

or two may be of the greatest importance and may require special con-
trol measures. Differences in climatic conditions and in the relative im-
portance of certain diseases and insect pests will therefore cause some
variation in spray practices. The relative time of applying the spray,
however, and the materials used are rather uniform ; hence, apple grow-
ers generally will follow, in part at least, the program given in table 2.
When in doubt as to the proper material or dosage or the possible injury,
consult your County Farm Advisor or County Agricultural Commis-
sioner.

HARVESTING

Time of Harvesting. — Harvesting dates are determined by (1) the va-
riety, (2) the season, (3) the location, and (4) the purpose for which
the fruit is intended.

Early apples to be marketed locally in limited quantities and solely
for cooking may logically be harvested considerably in advance of their
full size and color or the development of their characteristic flavor. There
is a definite demand for a limited quantity of such fruit when all else is
sacrificed for earliness. This demand for an inferior product is, however,
soon filled ; and to harvest the more important summer and fall varieties
so as to fill an order by a certain date, with no regard for maturity, can-
not be recommended. Premature harvesting, though undoubtedly ad-
vantageous to certain individuals, can only result in fruit of poor color

Bul.425] Apple Growing 53

and low quality. A few such shipments soon have a depressing effect
upon the subsequent returns that the majority of growers are able to
realize for the larger part of their crop. First shipments of California
Gravensteins, the first boxed apple to arrive on the eastern markets and
offered as a dessert apple, have frequently lacked their characteristic
flavor and color. Bitterpit, a physiological trouble that develops much
less on well-matured fruit, is also frequently so serious as to discount any
advantages of extreme earliness.

Although premature harvesting sacrifices size, color, and quality, too
late harvesting may mean excessive dropping and poorer keeping qual-
ity. The importance of these factors largely depends upon whether the
apples are to be stored and sold as fresh fruit, or dried. Fruit for drying
may be somewhat more mature than fruit for long keeping in storage.

Considering the variety, the relative earliness or lateness of the season,
and the purpose of the fruit, most commercial growers know from experi-
ence when their crop is ready. Their judgment is usually based upon sev-
eral considerations, among which the following are the most important :

1. The ease with which the apple can be removed from the fruit spur.
Dropping of sound apples is a natural sign of maturity, and most varie-
ties when ready for picking can be broken from the spur rather easily.

2. The taste of the fruit. Specimens should be cut and tasted. If hard
and starchy the fruit should, in all probability, be left on the tree for
several days at least. No variety, of course, will possess at this time its
characteristic aromatic flavor. The flesh should be decidedly firm and
sharply acid, but with practically no starchy taste.

3. Changes in color. With red apples, full color development is desira-
ble. Color, however, may vary rather widely in different districts and in
different seasons. If the weather be cloudy or foggy, the fruit may be
well developed and yet show little color when ready to pick. Where
weather conditions just before harvest time are ideal for coloring, the
fruit will assume its natural color often considerably in advance of the
proper time for picking. Particularly may this be true of the red bud
sports. The red or overcolor is therefore not an accurate indication of
ripeness. In varieties that are only partially colored a much more accu-
rate index is the green or yellow undercolor of the skin. Whenever this
color begins to change from a decided green to a slight yellowish green,
the fruit may generally be considered in the proper condition.

This initial change from the original dark green to a lighter shade is
also applicable to green varieties. With the Yellow Bellflower, color dif-
ferences may readily be observed ; but with the Yellow Newtown they

54 University of California — Experiment Station

can best be ascertained by comparison with the standard color chart
used by the State Department of Agriculture.

4. Firmness of the flesh. Softening is an unmistakable sign of ripening.
As the fruit pressure tester has shown, this softening starts before the
normal time of harvest. Thus, accompanying increases in color of the
fruit, there is normally a decrease in firmness. Both color and firmness
can be measured rather definitely, and considered together they furnish
a very good guide. Different varieties, however, vary in firmness just as
in color ; and firmness standards have been determined for only the more
important varieties.

In addition to these picking indexes some growers believe that apples
are ready for harvesting as soon as they attain a given size. Unless, how-
ever, size is considered with reference to other changes mentioned above,
its value as a picking index is questionable.

The darkening of the seed in apples is another rather unreliable cri-
terion sometimes followed to determine proper maturity for harvesting.
Although some varieties do have dark seed when ready to eat out of hand,
others are sufficiently mature to harvest for shipment before the change
occurs. In other instances, notably in Yellow Newtown, the seed may be
dark considerably in advance of the proper time for harvest.

Maturity Standards. — With the exception of a few varieties, the Cali-
fornia Standard Apple Act,17 which governs the grading, packing, and
sale of all California apples, specifies that all apples offered for sale shall
be properly matured, that is, "The apples in question at the time they
were taken or fell from the tree, had reached the stage of development
necessary to insure the proper completion of the ripening process."

As previously mentioned, most growers and the enforcers of this law
know fairly well from experience when fruit is sufficiently matured.
Early orders, however, frequently prompt growers to start harvesting
too soon, so that some of the specimens at least may be so immature as to
have the entire lot rejected by the local inspector, or to have its maturity
debated upon arrival at destination.

To avoid possible differences of opinion between grower or shipper
and the enforcers of the apple act, proper maturity of Gravenstein, Yel-
low Bellflower, and Yellow Newtown apples is now judged by certain
color and pressure requirements. These standards have been formulated
after several years of experimental work conducted jointly by the Divi-
sion of Pomology of the Agricultural Experiment Station and the Divi-
sion of Fruit and Vegetable Standardization of the State Department of

17 A copy may be secured from the Division of Fruit and Vegetable Standardiza-
tion, State Department of Agriculture, Sacramento, California.

Bul.425]

Apple Growing

55

Agriculture, who studied many samples harvested at different degrees
of firmness and color development.

To be considered mature, Gravenstein, Yellow Bellflower, and Yellow
Newtown apples must meet one of the following minimum standards :

TABLE 3

Minimum Maturity Standards of Color and Firmness for Harvesting Cali-
fornia Gravenstein, Yellow Bellflower, and Yellow Newtown Apples

Variety

Color
development*

Maximum pressure
test in poundsf

1:

/ lH-2

17.5
18.5

No restriction
17.0-18.0

No restriction
22.0-23.0

No restriction

* Figures refer to those used on the State Department of Agriculture color chart : 1 , original dark green ;
2, light green; 3, yellowish green.

t Figures refer to the pressure in pounds necessary to force a iVinch plunger point into the flesh of the
peeled fruit to a like depth.

In connection with this table it should be emphasized that all apples
should show some slight lightening of the original green ground color
before harvesting and that the fruit which meets only the minimum color
requirements of l1^-^ will rarely, if ever, ripen with more than fair
quality. Better size, greater yields, more red color and less bitter pit on
Gravensteins, higher sugar content, and better storage and dessert qual-
ity will all be secured by allowing the fruit to attain greater maturity.
Gravensteins and Yellow Bellflowers are more attractive and of much
better quality where not harvested until light yellow. Yellow Newtowns
are best when not picked until of a No. 2, or light green, to a No. 3 or
yellowish-green color, according to the locality in which the fruit is
grown or whether the strain is green or yellow.

Fruit harvested for drying should be fully matured but not soft.

Methods of Picking and Handling. — In harvesting, each specimen
should be grasped in the palm and removed from the fruit spur by a
quick upward turn of the wrist. A straight pull will result almost in-
variably in pulling the stem from the specimen and in tearing the skin
in the cavity. Any such break affords a source of infection for various
molds and rots. Tender varieties such as the Winter Banana and the
Stayman Winesap must be picked with special care; otherwise they
will show the finger marks of the picker, often within a few hours after

56 University of California — Experiment Station

removal from the tree. To remove varieties that naturally grow in clus-
ters, such as the Gravenstein, both hands must be used. When only one or
two apples are picked from the cluster, those remaining are apt to drop.

Lug boxes are usually distributed ahead of the pickers and stacked be-
tween alternate trees in the row. As fast as the boxes are filled they are
stacked, usually on the side of the tree protected from the afternoon sun.
If the weather is warm, fruit picked in the forenoon should, if possible,
be hauled to the packing-house before the heat of the day. Fruit picked
in the afternoon is often left stacked in the orchard overnight and hauled
in the following morning so that it reaches the packing-house compara-
tively cool. Any unnecessary delay between harvesting and placing the
fruit under low temperatures will result in poorer keeping quality.

Pickers should always be warned against filling the boxes so full that
when they are stacked upon one another the fruit will be bruised. Unless
time is of utmost importance, pickers should be paid by the day rather
than by the box. Although fewer boxes will be harvested, the fruit will
show much less bruising, and the tree will be left in much better condi-
tion for next year's crop. In anticipating the actual quantity of fruit that
any picker can harvest in a day, one must consider the size and distribu-
tion of the crop on the tree, the size of the tree itself, and the ease with
which the fruit can be reached.

Considerable care should be used in loading and unloading from the
wagon and in stacking boxes in the packing house. Pitching the boxes or
allowing them to drop for even a few inches always bruises some fruit.

REMOVAL OF SPRAY RESIDUE18

Control of the codling moth, necessary for the production of marketable
apples, demands the repeated use of lead arsenate spray. Even though
not always apparent, some of this spray material usually remains on the
fruit at the time of harvest. Since these residues may be deleterious to
health, the federal and state laws require that all apples offered for sale,
whether fresh or for drying, shall not show a residue in excess of 0.01

18 For more complete information on spray residue removal than is given here see :
Haller, M. H., Edwin Smith, and A. L. Kyall. Spray-residue removal from apples and
other fruits. U. S. Dept. Agr. Farmers' Bui. 1752:1-25. 1935.

Cox, Alvin J. The California fruit and vegetable 1933 spray residue problem. Blue
Anchor 10(12) :8-ll. 1933.

Anonymous. Washing apples and pears. Blue Anchor 11(3) :7. 1934.

Cox, Alvin J. Warning to driers of pears, apples, or apple pomace with regard to
spray residue. Blue Anchor 11(7) :14-15. 1934.

Anonymous. Spray residue tolerance tightened. Blue Anchor 12(3):12-13. 1935.

Anonymous. Details of construction of home built type fruit washer. Blue Anchor
12(4) :9. 1935.

Cox, Alvin J. Acid washing of fruit with the aid of heat. Blue Anchor 13(3) :7.
1936.

Bul. 425] Apple Growing 57

grain of arsenic trioxide, 0.01 grain of fluorine, or 0.018 grain of lead per
pound of fruit.19 To meet this tolerance most apples must be cleaned.

Wiping. — In some instances the residue on early apples, including
Gravensteins, may be so slight that wiping will be sufficient. Authorities
on spray-residue removal state, however, that wiping removes not more
than 25 per cent of the total residue present and that fruit may actually
accumulate residue from the cloths or brushes and thus test even higher
after wiping than before. Wiping can therefore be satisfactory only with
fruit having very little excess residue and only with frequent changing
of the cloths or brushes. As wiping has not been entirely satisfactory, it
will doubtless gradually give way to washing.

Washing with Acid. — For washing California apples a weak hydro-
chloric acid solution (1 to 1% per cent) has proved satisfactory. Com-
mercial hydrochloric acid is approximately % acid, *so that 3 gallons in
a hundred are required to yield a 1 per cent solution. The common Cali-
fornia spray practice makes unnecessary an alkaline wash such as sodium
silicate, or the use of both alkali and acid as found necessary in removing
the heavy oily residues in the Northwest.

Spray residue is most easily removed immediately after harvesting,
especially with varieties that develop a large amount of wax on the skin.
It is also more easily removed with a warm acid solution than with a
cold one. Since many California apples are harvested in warm weather
when water temperatures are relatively high, little attention has been
given to heating the acid solution. The necessity for heating will be de-
termined by the temperature of the water available, the strength of acid
used, and the amount and nature of the residue to be removed. In districts
where water temperatures at the time of harvesting may be only from
40° to 60° Fahrenheit, heating may be necessary. According to tests by
the Division of Chemistry of the State Department of Agriculture,20
apples successfully cleaned by a 1 per cent acid at 80° still carried an
excess of residue when put through a 1% per cent acid solution at 40°
to 60°. In other instances even a 2% per cent cold acid solution has failed
to be effective unless the fruit was washed several times. Little additional
cleaning is obtained by the stronger concentration of acid, more rinsing
is necessary, and the solution is more corrosive to the metal parts of the
washing equipment. A weaker solution at a higher temperature is there-
fore preferable.

19 These tolerances are established for 1936. As improvements are made in cleaning
it is expected that the tolerance for lead will be reduced to 0.014 grain per pound.

20 Cox, Alvin J. Warning to driers of pears, apples, or apple pomace with regard
to spray residue. Blue Anchor 11(7) : 14-15. 1934.

Cox, Alvin J. Acid washing of fruit with aid of heat. Blue Anchor 13(3) : 7. 1936.

58 University of California — Experiment Station

Heating may be accomplished by electric immersion heaters, hot water
or steam coils, or live steam released in the solution. Another very simple
aid, tested by the Division of Chemistry, is a U-shaped piece of 4-inch
iron pipe laid flat in the bottom of the acid tank and cut long enough so
that both ends of the pipe extend several inches beyond the end of the
tank. An upright vent is screwed on one end while a gas burner is at-
tached to the other. Compressed industrial gas is used for fuel, the heat
passing through the pipe serving to heat the solution.

It is difficult to make rules or general recommendations for all apple-
growing districts and conditions ; washing practices may be expected to
vary in different sections. A 1 per cent acid solution is, however, the
strength generally used. Salt may be added as an aid in removing arseni-
cal residues. Soil particles and other materials on the fruit constantly
weaken the acid and this loss must be periodically replaced. With agi-
tation of the fruit or of the solution during washing, Cox states :a In
general a consistantly maintained 1 per cent solution22 of hydrochloric
acid at 100° Fahrenheit with 10 to 15 pounds of ordinary salt added to
each 100 gallons, is recommended as usually adequate for spray-residue
removal in 40 seconds. The acid solution should be titrated every two
hours and kept to full strength."

The operation of testing the strength of the acid is a simple one. The
equipment needed is two 10-cc measuring pipettes graduated to 0.1 cc ;
a standard solution of sodium bicarbonate (23.0 grams to 1,000 cc of
water containing 25 milligrams of methyl orange indicator) ; and a
small bottle or cup. To make the test, fill one pipette from the acid tank,
and allow the excess to flow out until even with the mark on the upper
part of the stem. Then place the measured amount (exactly 10 cc) in
the bottle or cup. Fill the second pipette with the sodium bicarbonate
solution ; and after allowing any excess above the mark to flow out, allow
the solution to flow slowly into the container holding the acid, shaking it
meanwhile. At the point where the color of the acid changes from red to
yellow, note the number of cubic centimeters (cc) of sodium bicarbonate
used. Divide this number by 10 to obtain the per cent strength of the
acid. Thus if 7.5 cc of the sodium bicarbonate was required, the strength
of the acid is 0.75 per cent. Always use the same pipette each time for
the acid and for the sodium bicarbonate solutions, and rinse out the
former with some of the acid solution to be tested before taking sample.

21 Cox, Alvin J. [Mimeographed announcement; no title given.] California State
Dept. Agr. April, 1936.

22 Commercial hydrochloric acid tests 20° Baume, which indicates a concentration
of only approximately 32 per cent total acid. Three gallons of the concentrated acid
are therefore added to each 100 gallons of water to secure a 1 per cent solution.

Bul. 425] Apple Growing 59

To increase the concentration to any desired point, add one quart of
acid per 100 gallons for each 0.09 per cent of acid desired. To increase a
0.75 per cent solution to a 1.00 per cent solution would require a 0.25 per
cent increase or approximately 3 quarts of acid.

During the washing process, dirt, decay spores, and residue are re-
moved from the fruit ; this necessitates renewing the acid daily or after
1,000 to 1,200 boxes have been put through 100 gallons of solution. In
commercial washers the acid is usually drained off after each day's run,
and the tank rinsed out.

After the acid wash, the fruit should be rinsed thoroughly to prevent
damage from the acid solution or soluble residues. A simple test to deter-
mine whether or not all the acid has been removed is to taste the water
in the calyx basin of the apples ; if sour or tart rinsing is incomplete. For
most efficient rinsing a continuous supply of fresh water should be added
to the rinse tank as a spray on the fruit as it leaves the tank. Where only
a limited supply of water is available, so that rinse water must be used
continuously, it may be kept neutral by frequently adding small quanti-
ties of lime (approximately 2 pounds to each 50 gallons of water23) . In
that case, however, the rinse water should be renewed as often as possible.

Drying of washed fruit is not considered essential, although, to facili-
tate packing, most commercial washers are provided with some means of
removing the excess moisture.

There should be no damage to or shortening of the storage life of sound
apples that are properly washed and rinsed. Improper handling or lack
of attention to the washing process may, however, result in such injuries
as (1) acid burning, caused by leaving the fruit in the acid for an ex-
cessive period; (2) arsenical injury, caused by soluble forms of arsenic
building up in the washing vat or remaining on the fruit after washing ;
and (3) heat injury, caused by permitting the temperature of the wash-
ing solution to get too high.24 Obviously the remedy is to remove the cause.

Washing Equipment. — The type of washing equipment used will be
determined largely by the quantity of fruit to be washed. When this
amount does not justify better equipment, the fruit may be placed in
crates and merely hand-dipped in barrels or tanks. A somewhat more
expeditious and less laborious method is to dip in a partitioned trough,
one-half containing the acid or cleansing solution and the other the rinse
water. In each compartment is hinged a covered slat tray with handles

23 The rinse water should be free from any acid taste or if tested with blue litmus
paper show practically no change in color.

24 These forms of injury are illustrated and described in : Haller, M. H., E. Smith,
and A. L. Eyall. Spray residue removal from apples and other fruits. U. S. Dept. Agr.
Farmers' Bul. 1752:1-25. 1935.

60 University of California — Experiment Station

on one end.25 The fruit, placed on the tray in the cleaning solution, is
raised and lowered in it several times. The top is then lifted, and the
tray tilted sufficiently so that the fruit passes into the rinse portion of
the trough, where the same process is repeated.

Where larger quantities of fruit are involved and yet the expense of
a commercial washer is too great, growers have devised various types of
homemade washers operated either by hand or by an electric motor. The
simplest of these are known as notation washers because the fruit, forced
along by means of revolving paddles, floats in the solution. In other in-
stances the fruit is carried through the washer on a series of rollers.
Cloths, pieces of soft rubber, or brushes hanging in the acid compart-
ment turn the fruit as it passes under them and act as scrubbers. An
inclined conveyor dipping into the cleaning solution at the end of the
tank carries the fruit over into the rinse compartment, which is equipped
with a similar conveyor to lift it out into boxes or on to the sorting belt.
These machines, which vary considerably in size and details of design, are
simple and relatively inexpensive. Although they lack certain advan-
tages of the better commercial washers, they should prove entirely satis-
factory under California conditions. Drawings and specifications for
building one type appear in a recent bulletin issued by the United States
Department of Agriculture.26

Where the amount of fruit justifies the expense, the commercial flood-
type washers are best adapted for rapid cleaning. In these machines,
some of which have a daily capacity of 2,000 boxes or more, the acid
solution and the rinse water are pumped over or sprayed with consid-
erable force upon the fruit as it passes between revolving brushes or is
turned by a special type of conveyor. The brush type of washer has
proved especially efficient with residues that are difficult to remove.

PACKING27

Many of the apples grown in the Pajaro Valley and also in the smaller
apple districts are sold as "loose" apples. This fruit, destined for Cali-
fornia markets, is sorted and graded, but unwrapped. It may or may not

25 Illustrated and described in detail in: Cox, Alvin J. Warning to driers of pears,
apples, or apple pomace with regard to spray residue. Blue Anchor 11(7) : 14-15. 1934.

26 Haller, M. H., Edwin Smith, and A. L. Eyall. Spray residue removal from apples
and other fruits. U. S. Dept. Agr. Farmers' Bui. 1752:1-25. 1935.

27 The following publication has been drawn upon by the author in the preparation
of this section : Tufts, Warren P. The packing of apples in California. California Agr.
Exp. Sta. Cir. 178:1-31. 1927.

Also for a more detailed discussion of packing and of apple-packing houses see:
Pailthorp, E. E., and H. W. Samson. Northwestern apple packing houses. U. S. Dept.
Agr. Farmers' Bui. 1204:1-39. 1921.

Pailthorp, E. E., and F. S. Kinsey. Packing apples in boxes. U. S. Dept. Agr.
Farmers' Bui. 1457:1-21. 1925.

Bul.425] Apple Growing 61

be faced or arranged in the boxes, but the law forbids packing it accord-
ing to recognized apple packs. Interstate shipments, on the other hand,
must be wrapped and packed to insure successful shipment.

Previously, a considerable amount of packing was done in individual
orchards in some temporary packing shed or out-building, the grower
and his family doing much of the work. This type of packing has now
been largely discontinued, and most growers either sell their fruit loose
or haul it to a central packing house. Such houses are usually provided
with modern washing and grading equipment; the fruit is carefully
graded and packed by experienced helpers. Although packing is a slow
operation for the amateur, an expert will wrap and pack 125 to 150 boxes
in a nine-hour day. Besides handling the fruit expeditiously and eco-
nomically, central packing houses turn out a standardized pack for the
entire district. Carload quantities of fruit can be sold under a single
brand or trademark ; and the buyer, who purchases largely according to
specifications, can be assured of uniformity.

Grading and Sizing. — After removing any spray residue, the first step
in packing is to sort out and discard the cull fruit and to grade and size
that which is to be marketed. The former work is usually done by girls
or women standing or seated at endless grader belts that carry the apples.
These helpers should be able to see defects quickly and, as the fruit
passes before them, to classify it according to the proper grade. The pro-
visions of the California Agricultural Code relating to apple standards,
state that all apples shall conform to one of the following standards :
Extra Fancy, Fancy, Fancy Loose, C Grade, C Grade Loose, and com-
bination Fancy and C. Grade Loose.28

To be first or Extra Fancy, the fruit must not only be free from injury
but as nearly perfect in size, color, and shape as is possible in commercial
quantities. The percentage going into this grade, even in the best years,
will therefore be small.

The requirements for Fancy grade apples are in some respects the
same as for Extra Fancy. The essential difference is that there are no
color requirements and that the law permits slight defects (but not ap-
preciable damage) resulting from limb rubs, spray burn, sun scald,
russeting, drought spot, hail, frost, internal browning, or various dis-
eases and insect pests. Fancy grade apples comprise the larger percent-
age of those shipped and are the basis upon which most California apples
are judged. Growers and packers should therefore strive, especially in

28 Copies of these regulations giving the detailed requirements for each grade may
be obtained from the Bureau of Fruit and Vegetable Standardization, State Depart-
ment of Agriculture, Sacramento, California. The grades given are those revised
for 1936.

62

University of California — Experiment Station

unfavorable or small-crop years, to grade carefully and not "crowd" the
pack by including fruit that belongs in the C Grade.

The C Grade includes apples lacking in normal color and shape or
showing appreciable (but not serious) damage from the defects men-
tioned above. All apples of these three grades must be uniform in size,
within limits of % to % inch and, with the exception noted under "Con-
tainers and Methods of Packing," may be packed, when wrapped, only
in standard-sized containers.

Where apples are not packed as one of these grades they may be
graded and sold as Fancy Loose, C Grade Loose, or a combination of the
two. Fancy Loose apples must be of the same general quality as Fancy

TABLE 4

Diameter Measurements and Number per Box of

Commercial Sizes of Apples

Diameter in
inches

Number per
box

Diameter in
inches

Number per
box

3%
3%
3%
3

2%

80

88

96

113-125

125-138

2%
2%
2%
2%

138-150
163-175

175-188
200-216

and differ generally only in that they may lack uniformity of size. All
specimens, however, must be 2*4 inches in diameter or over.

The C Grade Loose apples conform to the requirement of C Grade ex-
cept that there are no size restrictions and the fruit does not have to be
hand-picked. Gravenstein apples that will not pass through a 2%-inch
ring need not be properly matured to make this grade. In the combina-
tion Fancy and C Grade Loose, all Gravensteins shall be mature ; and not
less than 50 per cent, by count, of apples must meet the requirements for
the Fancy Loose grade. There are no restrictions regarding the size or
type of container for loose apples when in an open or unlidded container.

Commercial apple packs commonly found on the market cover a range
of ten to fifteen sizes, the size in each case being indicated by the number
of apples packed in the box. Each size packed varies in its diameter
measurements as much as %6 to % inch. In central packing houses and
in others equipped with mechanical fruit sizers, the apples are automati-
cally sized to approximately % inch variation as they drop into the
various bins. The packer may further segregate the specimens in each
bin into two sizes. Actual dimensions vary slightly with different varie-
ties, but average diameters for the different packs are shown in table 4.

To distinguish the different sizes is the most difficult phase of packing.

Bul. 425]

Apple Growing

63

For the amateur, who may have to do his sizing by hand, a measuring
board of light wood or heavy cardboard in which a series of holes of
different sizes are cut will prove helpful in first separating and fixing in
mind the different sizes. Continued practice for a few days in picking
out the various sizes will soon enable one to recognize them.

Containers and Methods of Packing. — The California Agricultural
Code specifies that all wrapped apples must be packed in the standard
apple box, inside depth 10% inches, inside width 11% inches and inside
length 18 inches; or in a half apple box 5% X 11% X 18 inches, inside

Fig. 12.-

-Diagrammatic sketch showing method of starting different apple packs :
A, two-one; B, two-two; C, three-two; B, three-three.

measurement. Smaller packages for wrapped apples than the half box
are permissible only where the package is conspicuously marked in let-
ters not less than % inch high : "Irregular Container." Wrapped apples
are packed almost exclusively in the standard apple box, holding when
well packed 44-48 pounds of fruit.

As previously mentioned, there are at present no regulations govern-
ing the size or type of container for unwrapped and unpacked apples in
open containers. Many of the latter are sold either loose or packed (un-
wrapped) in various types of lug boxes and in paper cartons.

Styles of packs are usually spoken of as the "two-one" pack, the "two-
two" pack, the "three-two" pack, and the "three-three" pack (figure 12) .
These differences in arrangement crosswise the box, with the variation
in the number of apples lengthwise and the number of layers, accommo-
date all the different sizes.

The two-one pack (fig. 12, A), containing only three layers, is rarely
used, being designed to care for only the largest apples — those so large
that when one is placed in each corner of the box the space remaining
between them will be approximately only half large enough for a third

64

University op California — Experiment Station

apple. Where this space is sufficiently large to permit the three apples
but not four in a straight row crosswise of the box, then the two-two
arrangement shown in figure 12, B should be employed. This style of
pack is four layers in depth and will accommodate sizes which are from
48 to 96 to a box. The first layer of this pack is started as shown in the
figures given above. The individual fruits in the second and third layer
fit in the pockets formed by the apples beneath.

The three-two arrangement, five layers in depth, finds greater use
than any other pack because it cares for all the medium and some of the
medium to small-sized fruit — usually sizes 100 to 175. This pack should

TABLE 5

Apple Packs

Arrange-
ment
cross-
wise

Number
of fruits
in rows
length-
wise

Number

of layers

in

depth

Number

of fruits

in

box

Arrange-
ment

cross-
wise

Number
of fruits
in rows
length-
wise

Number

of layers

in

depth

Number

of fruits

in

box

2-1
2-2
2-2
2-2
2-2
2-2
2-2
3-2
2-2
3-2
3-2

4X4
3X3
4X3
4X4
5X4
5X5
6X5
4X3
6X6
4X4
5X4

3
4
4
4
4
4
4
5
4
5
5

36

48

56

64

72

80

88*

88f

96
100
113

3-2
3-2
3-2
3-2
3-2
3-2
3-3
3-3
3-3
3-3
3-3

5X5
6X5
6X6
7X6
7X7
8X7
5X5
6X5
6X6
7X6
7X7

5
5
5
5
5
5
6
6
6
6
6

125

138

150

163

175*

188

180

198

216

234

252

* For flat apples. t For long apples.

be used with apples where four in line would fill the box crosswise or
where, as in figure 12, C, the fourth and fifth apples placed in the box
cannot slip more than halfway into the spaces formed by the first three
placed next to the end. In constructing the pack, the bottom layer is com-
pleted by repeating the same arrangement as shown. In the second layer
the individual fruits are again placed so as to fit into the pockets formed
by the apples beneath. The layer will be started with two apples instead
of three. Layers 1, 3, and 5 and layers 2 and 4, will be identical, respec-
tively.

For apples smaller than 175-188, or at least for those measuring less
than 21/4-2% inches in diameter, so that five apples would form a
straight line crosswise of the box, the three-three pack is generally used.
The arrangement for starting is shown in figure 12,D. It is continued in
similar fashion to the three-two pack except that three apples are used
each time across the box. This pack contains six layers, the fruits being
placed in the same general manner as already described. Table 5 shows

Bul. 425] Apple Growing 65

the general range of sizes and the arrangement of the more common
packs.

Liners and Wrapping Paper. — To add a finished appearance and also
to protect the apple, lining paper is generally used in packing the better
grades. Either the ordinary "white news" stock or special types of col-
ored paper may be employed. Two sheets, 17 % X 26 inches, are placed
in each box before packing. These overlap on the bottom and fold over
the top after the box is completed. To avoid tearing when the bottom
bulge is formed by lidding, an extra fullness must be left at the bottom
edges. Besides the liners, boxes of all shipments of Gravensteins for ex-
port and some of those for domestic markets carry a top and bottom pad
to protect against bruising.

Wrapping the individual fruits aids in packing by holding the speci-
mens in place, reduces bruising, prevents spread of decay, and reduces
transpiration losses. It also gives the package a more finished appear-
ance, particularly if each wrap carries the printed brand or trademark
under which the fruit is sold. Fruit wraps are now made mostly from
light-weight, tough, and usually partly transparent paper. Oil-treated
wraps are now largely used where the fruit is to be stored, as a preventive
against scald. Apple wraps are usually purchased in 50-pound bundles
and can be secured in various sizes to accommodate fruit of different
sizes. For extremely large apples, paper 12 X 12 or 14 X 14 inches should
be used. For sizes 64 to 80, 11 X 11 ; sizes 88 to 113, 10 X 10 ; sizes 125 to
180, 9X9; and sizes less than 180, 8X8. One-half pound of paper is
sufficient to pack a box of average-sized apples, 10 X 10 wraps running
approximately 300-325 sheets to the pound.

Details of Wrapping and Packing. — Methods of wrapping vary
slightly with different packers, who, as they gain skill, have devised some
special system of their own. Figure 13, however, shows the essential
steps of one simple and rapid method. In figure 13,A, the packer is pick-
ing up the wrapper with his left hand and an apple with his right. A
rubber fingerstall worn on the forefinger of the left hand aids in picking
up the wraps. These are grasped by the forefinger and thumb toward
one of the upper corners. The apple is next tossed, stem end up, into the
upper half of the wrap held in the left hand, while the right hand, with
no lost motion, takes the position shown in figure 13, B. The next step is
accomplished by continuing the upward movement of the right hand and
the turning down of the palm of the left hand (fig. 13, C) . Wrapping is
completed by a rolling over or twisting motion of the left hand (fig.
13, D). Little or no wrapping is done with the right hand, its function
being merely to afford a solid working surface for the left. In figure 13, E,

66 University of California — Experiment Station

W jt / I

MmJ1

*J

Sfcjft

V , jfl

•.-,', -;:' v" < ^

Fig. 13. — Five steps in wrapping apples. (From Cir. 178.)

Bul.425] Apple Growing 67

the wrapped fruit is being placed in the box by the left hand while the
right starts reaching for another apple.

Once learned, wrapping is a simple operation; but the ability to gain
speed and to wrap neatly and smoothly, with all the loose ends of the
wraps tucked in, can be acquired only through practice and experience.
Proper-sized wraps for the fruit being packed should always be used.
These are held in convenient positions on a tray or holder on the side of
the box.

As indicated in the diagrams of figure 12, showing styles of packs, the
apples are always placed in the box on their side with the stem always
pointing away from the packer. The spaces between the apples must be
kept equal, and the alignment watched. Good spacing and alignment are
easily obtained where the specimens are uniformly sized and are not
permitted to turn sideways after being placed in the box. Where the
fruit is of variable size, however, to make up a satisfactory pack is
almost impossible.

Packing continues by placing the apples in the box in regular order
until the first layer is completed and the fruit is held firmly in place by
the pack. Proper compactness, spacing, and alignment of the first layer
is of prime importance, for it governs the arrangement in subsequent
layers and the total number of apples that must comprise the pack. The
second and subsequent layers are constructed like the first by placing
the apples in the pockets formed for them by the specimens beneath.
Never allow an apple to be forced out of these pockets ; the result will be
a "broken" and irregular pack.

During transportation or storage, fruit shows slight shrinkage. To
insure against the specimens' becoming loose and bruised, apple packs
are constructed with a bulge of about 1% inches, which after lidding is
about equally divided between the top and bottom of the package. This
extra height of the apples in the center of the box may be secured either
by pulling the center specimens in each layer slightly closer together
than those at the ends, which makes the pockets smaller and increases
the height of subsequent layers ; or by packing the apples near the center
of each layer in the box so that their longest crosswise diameter is per-
pendicular to the bottom of the box. Conversely the specimens in the first
and last two rows at the ends should be turned with their shortest diam-
eter in this direction. The ends of the completed pack should not extend
more than *4 to % inch above the ends of the box. This fruit is, of course,
forced down more closely into the pockets beneath when the box is lidded.

Difficulty is frequently experienced in getting the pack to finish at the
proper height ; packers must learn just how tight to pull the apples in

68 University of California — Experiment Station

each layer in order to build a perfect pack. The looser the pack the higher
it may be built without bruising the apples when the box is lidded. Also
the larger the apples in any given style of pack, the more loosely they
should be placed in the box. Apples of sizes 100 and 175 are both packed
in five layers according to the 3-2 arrangement, but in order to secure
the proper height the smaller apples must be drawn closer together as
packed.

Not only should the top layer of the pack come to the proper height in
the center and at the ends, but the entire surface should be regular and
even. Any individual specimens standing higher than those adjacent are
subject to bruising or cutting as the lid is pressed down and nailed in
position.

Stamping and Labeling. — As the packed boxes reach the nailing press,
before lidding, the nailer or some other designated person must stamp
the following information on one end of the box : variety, grade, number
of apples in the box (within 5 of the true count), date of packing, and
either the minimum net weight of the apples or the cubical contents of
the box. The box must also show the name and address of the person
authorizing the packing or the number under which such packer is en-
gaged in business. This information usually appears on the lithographed
label pasted immediately under the stamped information. Different
labels or different color combinations show the brand under which the
fruit is packed and serve as a useful means of identifying the grade.
Well-chosen lithographing also lends attractiveness and aids in adver-
tising. Packed apples held in cold storage for more than thirty days must
be so marked.

According to present requirements, open containers of apples that are
not packed (arranged) need show only the grade and name and address
of the person who first placed or authorized the placement of the apples
in them.

STORAGE

Although little of California's Gravenstein crop harvested in July finds
its way into storage, a large share of the later varieties must be held
throughout the winter. The Yellow Newtown, grown in the Pajaro Val-
ley, is stored most extensively. Local storage can care for approximately
1,400,000 boxes. In addition, part of the crop may be stored for short
periods in the commercial cold-storage plants of the larger consuming
centers. Such plants must also care for that portion of the fruit which is
stored from the smaller producing districts.

Types of Storage. — The most efficient type of storage for long holding
is the "cold storage," where low temperatures are secured and maintained

Bul. 425]

Apple Growing

69

by mechanical means. The rooms are cooled by the direct expansion of
ammonia in coils on the walls or beneath the ceiling, by air circulating
through the room and then over coils or through a brine spray in a
bunker room, or by a combination of the two systems. In the newer
plants, including the smaller individually owned houses, the air-circu-
lating system is employed. A good circulation of air and some provision

SUC&CSTCD ARRAN&MENT
OF IHLCT OOCT .
FOR SLOPING (ROUND

Fig. 14. — Diagrammatic cross section of air-cooled storage house showing general
type of construction for maximum air circulation and most satisfactory air tempera-
tures. Vents are opened at night and closed during the day or whenever the tem-
perature inside the house is below that of the outside air.

for ventilating are desirable both for cooling large blocks of warm fruit
quickly and for keeping the room relatively free from odors and noxious
vapors.

Small automatic refrigerating units, similar in their operation to a
mechanical refrigerator, are an innovation for ranch storage houses. The
possible advantages of such a house over a centrally located commercial
or cooperatively owned plant at trackside will be governed by such fac-
tors as the relative cost, including the original investment and overhead
charges, the amount of fruit to be stored, and the general convenience in
relation to washing, packing, and other handling operations. Occasion-
ally where an individual purchases and packs fruit in addition to what
he himself produces, such storage houses have been constructed in con-
nection with the packing house.

In addition to refrigerated storages, many Northwest apples are suc-
cessfully held for a number of months in ventilated or "air-cooled" stor-
ages constructed either aboveground or underground. Such houses may
be used with considerable success in sections of California where night
temperatures at harvest time and thereafter drop relatively low. All air

70

University of California — Experiment Station

intakes and outlets of the house are opened each evening, a free circula-
tion of air is allowed during the night, and then all ventilators are closed
the following morning as the outside temperature rises above that in the
house. This type of house is most efficient where the intake air in above-
ground houses is brought in at the ground level and the fruit is stored

Fig. 15. — Interior view of a large cold-storage room at Watsonville,
showing method of stacking boxes of loose apples.

on an open floor, constructed of 2 X 4's, some 18 inches above the ground.
The vents for the outgoing warmer air should be overhead and should
extend for a short distance above the roof of the building. Such a con-
struction insures the maximum amount of draft through the house for
cooling. In basement storages, doors may be used for air intakes ; or the
incoming air should be conducted from the ground level to the floor of
the cellar or basement through wall flues (fig. 14).

If water is available, shriveling of the fruit may be reduced by keep-

Bul. 425]

Apple Growing

71

ing the soil wet beneath the raised floor. If the fruit is to be held during
freezing weather, aboveground houses must be constructed with in-
sulated walls and ceiling, or some provision must be made for heating.
Methods of Storage. — With the Yellow Newtown known as the chief
storage variety and largely sold on local markets as unpacked fruit, most
California apples are stored loose in open boxes. Except occasional small

Fig. 16. — Interior view of cold-storage room, showing method of stacking
packed Gravensteins awaiting export shipment. (Courtesy of the California
Fruit Exchange.)

lots from the lesser districts, only Gravenstein and Yellow Newtown
apples awaiting export shipment are stored wrapped and packed.

Loose fruit in open boxes and fruit in boxes packed and lidded are
stored differently, primarily in that the former must be stacked in an
upright position and at least one-third more storage space is required
to accommodate an equal amount of fruit. To handle large quantities of
bulk fruit the cold-storage plants in Watsonville contain rooms with
sufficiently high ceilings to permit stacking 18 to 20 boxes high. This
arrangement necessitates much extra handling, for the stacks are built
in steps, and the fruit must be passed up from one to the other. Packed
boxes, always stored and handled on their side to prevent damage on
the bulged top and bottom, are usually stacked low enough to be lifted
by a man standing on the floor or a low platform.

72 University op California — Experiment Station

Whether packed or loose, the stacks should be raised 4 to 6 inches from
the floor by placing the bottom boxes on properly spaced timbers. Indi-
vidual stacks in large blocks of fruit, especially if packed, should be
separated by a small air space. The boxes in individual stacks are also
separated, and the stacks held firmly in place by dunnage strips. Figures
15 and 16 illustrate typical methods of stacking loose and packed fruit.

Storage Conditions Influencing Keeping Quality. — Three storage fac-
tors may be mentioned as important in maintaining apples in good con-
dition : a low temperature, a high relative humidity, and an atmosphere
kept free of noxious odors or gases.

A low temperature is the most practical and effective means of retard-
ing ripening. For holding apples for the maximum period of time a tem-
perature of 31°-32° Fahrenheit (2y2° to 3° above the freezing point)
has long been recommended for most apple varieties. Experience with
Yellow Newtowns grown in the Pajaro Valley has shown, however, that
this variety is subject to a low-temperature injury known as internal
browning; and to reduce this injury a temperature of 36° is recom-
mended.

Investigators at the Iowa Agricultural Experiment Station29 are also
recommending a temperature of 35°-36° Fahrenheit for apples picked
at proper maturity and carefully handled. They have found that this
higher temperature has resulted in better flavor and color.

Although low temperature is effective in holding ripening changes to
a minimum, apples removed from storage after being held for a consid-
erable period may show a certain sponginess and may lack crispness.
This condition is due to excessive moisture loss from the fruit through
transpiration and may be prevented by maintaining a high relative
humidity in the surrounding air. Since a relative humidity of 85 per cent
gives fairly satisfactory results with wrapped fruit, this percentage of
saturation has generally been recommended. At present, however, more
experimental work is being done to determine optimum humidities more
accurately; and it seems safe to state that apples in cold storage at 32°
Fahrenheit will remain more firm and crisp if held in an atmosphere of
90 to 95 per cent saturated. At air-storage temperatures of 45°-60° this
higher humidity may render the fruit somewhat more susceptible to
attack by various rots; but if all damaged specimens are sorted out
before storage and the fruit is held in clean boxes, decay should be slight.
Regardless of storage conditions all stored fruit should be inspected at
various intervals to determine its keeping quality.

^Plagge, H. H., T. J. Maney, and B. S. Pickett. Functional diseases of the apple
in storage. Iowa Agr. Exp. Sta. Bui. 329:1-79. 1935.

Bul. 425] Apple Growing 73

Besides being benefited by cold, moist air, apples are much less likely
to develop scald (see discussion of storage troubles) where the atmos-
phere surrounding them is kept relatively free from the odorous vapors
they give off. Oiled wraps that absorb such toxic vapors are one means
of reducing scald. Such wrappers have given, however, only indifferent
results with Pajaro Valley Newtowns; and unwrapped fruit held in
rooms receiving good circulation and adequate ventilation are likely to
be most free of this trouble. Un ventilated rooms in which large quantities
of fruit are stored may have an atmosphere containing several per cent
of carbon dioxide. Carbon dioxide in itself, however, is not apt to become
so concentrated as to prove harmful. Its action in reducing respiration
has, under some conditions, in fact proved decidedly beneficial in main-
taining the fruit firm and (in green varieties) of its original color.
Numerous commercial storages are in operation in England for holding
apples in atmosphere containing 5 to 10 per cent carbon dioxide, and the
possible advantages of this method for California are now being studied.

Other Factors Influencing Keeping Quality. — Failure of fruit to keep
well in storage may or may not be the fault of the storage operator. The
warehouseman's responsibility is to supply proper temperature and air
conditions and to take immediate steps to correct any trouble. Even
under optimum storage conditions, however, apples sometimes fail to
keep well ; and in these instances the trouble must result from some in-
herent weakness in the fruit itself due to conditions under which it was
grown or to the time of picking and the manner of handling before
storage.

The time of harvesting for storage and the method of handling before
delivering to the storage are the grower's responsibility; not infre-
quently, poor keeping quality can be traced to injudicious harvesting or
handling. Apples allowed to remain on the tree too long tend to break
down and to become mealy in storage. This fact, however, does not justify
the conclusion often drawn that early-harvested apples will keep better
than those allowed to become riper. The determining factor is the actual
degree of maturity at harvest. Immature fruit will not break down and
become mealy, but it is subject to shriveling and to scald and will fail to
ripen with its characteristic color or flavor. For optimum storage, apples
should be harvested at maturity and not before. (See section on tests for
maturity. )

After being harvested, apples should be hauled in, cleaned, graded,
and placed under storage temperatures with the least possible delay.
Although the damage is not apparent at the time, allowing fruit to stand
in the orchard or even the packing house for several days may mate-

74 University of California — Experiment Station

rially shorten its storage life. Any rough handling resulting in bruises,
skin punctures, and the like will also be reflected later in storage. Wash-
ing in hydrochloric acid of the strength previously recommended should
not, with proper rinsing, injure the keeping quality.

Storage Periods for California Apples. — The period of greatest con-
sumption for the leading California varieties is given under the variety
descriptions. Few varieties except Yellow Newtown and Yellow Bell-
flower are stored in quantity. Yellow Bellflower may be kept until
November or December or even later, though such practice is usually
unprofitable. Yellow Newtowns have a variable period of storage depend-
ing somewhat upon their susceptibility to internal browning. Some fruit
should not be stored longer than two or three months, whereas that from
other orchards may be held until May. Gravensteins, if well matured
when harvested, may keep very well for several months but are rarely
stored because of meeting better sale in July and August. The general
storage period for other varieties held at 32° F are Jonathan, White
Pearmain, Tompkins King, Spitzenberg, and Delicious, four to five
months ; Rome Beauty, five to six months ; and Winesap, seven to eight
months.

Where apples are stored their season will naturally be much shorter,
the length of their storage life largely depending upon the temperatures
maintained. Quantities of apples held for commercial use should never
become full eating ripe before leaving storage. Late in the season the
fruit will ripen very rapidly at the higher outside temperatures and may
become overripe or develop scald or other trouble before it can be sold
and used.

STORAGE AND MARKET DISEASES30

The life of apples in storage may be terminated by the general internal
breakdown of old age, or by some physiological disease or fungus rot. A
few of these troubles will be briefly mentioned.

Internal Breakdown. — Internal breakdown is associated with a gen-
eral overripe condition and marks the end of the storage life of fruit not
otherwise affected. Apples lose their firmness and juiciness; the flesh
becomes dry and mealy — in severe cases soft and brown. The disease,
which is sometimes mistaken for freezing injury, most often first occurs
on large-sized overmature fruits. Late harvesting, delay in storage, and
high temperatures all favor its early development. The amount and
seriousness of the trouble varies from year to year, being influenced by

30 For a more complete discussion of storage troubles see : Eose, Dean H., Charles
Brooks, D. F. Fisher, and C. O. Bratley. Market diseases of fruits and vegetables —
apples, pears, and quinces. U. S. Dept. Agr. Misc. Pub. 168:1-70. 1933. This publica-
tion has been drawn upon in the preparation of this section.

Bul. 425]

Apple Growing

75

growing conditions. Naturally internal breakdown appears sooner and
is more serious in fruit held in air-cooled storage houses than in cold-
storage fruit.

Bitter Pit. — Bitter pit, which occurs in all important apple-growing
regions of the world, is particularly important in California on the
Gravenstein variety. Early-picked fruit showing no signs of the disease
when packed may be badly infected 10 days later when it arrives on the

Fig. 17. — Bitter pit in Gravenstein apples.

eastern markets. Bitter pit also frequently appears in less severity in
storage on Yellow Bellflower, Yellow Newtown, Winter Banana, Deli-
cious, and other varieties.

As illustrated in figure 17 the disease is characterized by small sunken
spots, largely concentrated over the blossom end of the apple. At first
these appear as water-soaked bruiselike spots on the surface, later turn-
ing dark green (on green apples) . Finally, as the disease advances, they
become depressed or sunken into definite pits of regular outline that take
on a brownish color. When the skin is removed, the dead brown pulp
cells appear in the flesh. Although these areas are associated with the
ends of the vascular system of the fruit, they may appear throughout
the flesh.

Bitter pit is a physiological or nonparasitic disease. Investigators have
advanced numerous theories as to its origin without entirely proving
any. Certain individual facts, however, are known and are helpful in
reducing losses. Generally speaking, the trouble is worse on fruit from

76 University of California — Experiment Station

young trees than on that from older trees ; worse on large fruit than on
small ; worse in years of light crops, or heavy rainfall, or late irrigation.
Fruit picked immature suffers much worse than fruit picked well ma-
tured. Apparently, therefore, certain factors influencing the nutrition
and water supply during growth and early ripening have an important
bearing upon bitter pit development, and the severity of the disease may
be reduced by orchard practices tending to promote uniform crops and
tree growth and by harvesting only mature fruit.

As growing conditions vary somewhat from year to year, a seasonal
difference is likewise often seen in the development of bitter pit. There
is some evidence that the fruit from certain trees is more susceptible
than that from others.

Immediate storage of apples at cold-storage temperatures will retard
but not prevent bitter pit. In fact, fruit ripened after storage at a low
temperature seems to develop more pitting than that ripened imme-
diately at 70° Fahrenheit. Bitter pit does not spread from one apple to
another in transit or in storage.

Internal Browning. — Internal browning is another physiological
trouble apparently due to certain abnormal nutritional conditions in the
tree that affect the fruit. It has little or no economic importance outside
the Pajaro Valley, but in that section it is the most important trouble
affecting the Yellow Newtown. Except in advanced stages the trouble
is not apparent from any abnormal external appearance of the skin, and
the fruit must be cut to determine its presence. A softening at the basal
end of the apple around the stem, however, is an indication of severe
browning.

The disease is first noticeable usually in December or January ; then,
when the apple is cut in cross section, one-third the distance between
stem and blossom end, more or less elongated and slightly discolored
areas radiate outward from the central portion. At first the discoloration
is only slight, and the areas are adjacent to the primary vascular bun-
dles. As browning becomes more severe, however, they spread rapidly
to the secondary bundles, and finally the condition may become more or
less general (fig. 18) . When the disease reaches its worst stage the thick-
walled cells of the epidermis turn brown and the fruit appears as though
infected with scald. In some instances browning may be confined largely
to the core region, this sometimes being designated as "core browning"
to distinguish it from the more usual form.

Both state and federal investigators who have worked on the problem
find that the conditions which produce browning in the Pajaro Valley
are closely associated with a relatively low growing temperature and

Bul. 425] Apple Growing 77

a high humidity, climatic conditions characterizing that section. The
browning is generally worse in fruit from the valley floor, where these
conditions are coupled with a fertile heavy type of soil. Fruit grown in
the hill sections is less susceptible and frequently shows no browning.

Winkler,31 by experimental means, developed fruit under temperatures
both above and below the normal. Where the mean daily temperature
was raised approximately 4° C above normal, little browning occurred,
whereas with a similar decrease in temperature 95 per cent of the speci-

Fig. 18. — Internal browning of Yellow Newtown apples. Left, severe browning;

right, normal apple.

mens showed more or less browning. As these results indicate, browning
throughout the district should be more severe in years of low summer
temperatures. According to the popular belief, this is true ; yet other fac-
tors frequently mask or nullify the results of variation in temperature.
During the past few seasons results have been secured on the amount of
browning in ten different orchards, and the severity of the trouble could
not well be correlated with mean growing temperatures. One orchard
has consistently produced fruit extremely susceptible to browning each
year whereas others near by have shown much less of this trouble. A con-
siderable variation is found not only between different orchards but be-
tween different trees growing close together.32

Ballard reported that browning was much worse in large fruit and in

81 Winkler, A. J.. A study of the internal browning of the Yellow Newtown apple.
Jour. Agr. Research 24(2): 165-84. April 14, 1923.

32 These observations of the writer confirm the results reported in the following :
Overholser, E. L., A. J. Winkler, and H. E. Jacob. Factors influencing the develop-
ment of internal browning of the Yellow Newtown apple. California Agr. Exp. Sta.
Bul. 370:1-40. 1923. (Out of print.)

Ballard, W. S., J. E. Magness, and L. A. Hawkins. Internal browning of the Yellow
Newtown apple. U. S. Dept. Agr. Bul. 1104:1-22. 1922.

78 University of California — Experiment Station

light crop years and that heavy thinning and fertilizing tended to in-
crease its severity. Overholser, Winkler, and Jacob found the size of the
crop to be an influencing factor but fruit both from weak and from ex-
cessively vigorous trees to be more susceptible to browning than that
from trees of normal vigor. More browning was also found in apples from
old trees than in those from young ones. Numerous factors relating to
growth seem, therefore, to be involved.

Picking and storage practices are also an influence. The writer's re-
sults have confirmed those of the previous investigations in that the sever-
ity of browning increases somewhat with the maturity of the fruit. Of
all the factors influencing the development of browning, however, stor-
age temperature is the most important. Fruit from trees known to be
susceptible will not brown if held at 45° Fahrenheit and will develop
much less of the trouble at the recommended storage temperatures of
36°-38° than at 32°. Browning increases rather rapidly after the fruit
is removed from storage.

The real cause has not definitely been determined. Winkler and his
associates believe that browning is closely related to apple scald and that
its probable cause is the accumulation of essential oils or other deleterious
substances produced by the apples in storage. From their preliminary
tests, ventilation of storage rooms and sometimes use of oiled fruit wraps
appeared advantageous.

Scald. — Apple scald (fig. 19) is one of the most serious and widespread
storage diseases. Unlike internal browning it occurs in all apple sections
and on most varieties, among which Arkansas (Mammoth Black Twig),
Grimes Golden, Rome Beauty, Rhode Island Greening, Wagener, Stay-
man Winesap, Winesap, and Yellow Newtown are highly susceptible.
Scald is primarily a skin disease, which in mild cases appears as a super-
ficial browning. On red varieties it is confined primarily to the greener
side of the fruit. In severe cases the entire surface may become discolored
and separate from the pulp. Occasionally in the later stages the flesh
may likewise become brown to a depth of % inch or more.

The immediate cause of scald, according to federal investigators,83 is
the accumulation, within the apple tissues, of certain gases or vapors
(other than carbon dioxide) given off by the apples themselves as a
result of respiration. This being true, the remedy is to remove these gases
by providing sufficient air circulation and ventilation in storage or else to

33 Brooks, Charles, J. S. Coolev, and D. F. Fisher. Apple scald and its control.
U. S. Dept. Agr. Farmers' Bui. 1380:1-16. 1923.

Eose, Dean H., Charles Brooks, D. F. Fisher, and C. O. Bratley. Market diseases
of fruits and vegetables — apples, pears, quinces. U. S. Dept. Agr. Misc. Pub.
168:1-70. 1933.

Bul. 425]

Apple Growing

79

absorb them by means of oiled fruit wraps. The latter method is gener-
ally recommended for packed fruit which is to be stored. In California,
as previously stated, most Yellow Newtowns are stored loose. Unwrapped
fruit shows decided less scald than wrapped ; but where large quantities
are tightly stacked, cooled slowly, and held at a minimum temperature
of 36° Fahrenheit, conditions favor scald development. Slight scald in

Fig. 19. — Apple scald of Yellow Newtown apples.

storage is apt to become serious within a few days after the apples are
removed.

Storing at 32° Fahrenheit is not advisable with Pajaro Valley New-
towns because the fruit shows much more internal browning at this tem-
perature. More open stacking, however, and good air circulation that
permits more rapid cooling, once the fruit is in storage, together with
some ventilation during the first month or six weeks, are recommended
practices.

Aside from rapid cooling, low temperatures, and good ventilation in
the storage room, the time of harvesting, and cultural and handling
methods have a bearing upon scald development. Immature fruit and
poorly colored red varieties are particularly subject to scald, and this
susceptibility is intensified by delays between the time of harvesting and
of placing in storage and cooling. Apples from heavily irrigated trees

80 University of California — Experiment Station

have also been found by federal investigators to be much more subject
to scald than those irrigated moderately.

Soft Scald. — Soft scald differs from that described above in that the
affected areas are depressed and well denned. The browning of the skin
and flesh is characterized by a sharp demarcation between the diseased
and healthy tissue. The spots vary in size from V4 inch or less in diameter
to rather large areas covering a considerable portion of the surface. The
flesh beneath such areas is usually soft, spongy, and moist, but may be-
come dry and collapsed. The disease occurs less frequently than ordinary
scald but may sometimes cause serious losses on such varieties as Rome
Beauty and Jonathan.

Soft scald is believed to result from abnormal respiration of the apple
at low temperatures and is greatly increased by any delay in getting the
fruit into storage. Plagge,34 Maney, and Pickett recommend a storage
temperature of 36° Fahrenheit rather than 32°, whereas Rose and his co-
workers found that no injury occurred at 32° where the fruit was pre-
viously exposed for two days during cooling in an atmosphere contain-
ing 20 to 30 per cent carbon dioxide. The oiled wrappers ordinarily rec-
ommended for scald will not control this disease.

Jonathan Spot. — Jonathan spot is another skin disease often preva-
lent on storage apples in many apple sections but confined largely to
the Jonathan variety. The spots are at first brown or blackish, very
slightly sunken, roughly circular, and from y1Q to % inch in diameter.
Later they may increase in size or coalesce. In the early stages the spot-
ting is confined to the color-bearing cells of the skin ; but after the skin
is killed, underlying tissues may become affected. Spotting is most severe
on highly colored specimens. The cause of the disease is unknown. Imme-
diate storage, however, reduces its severity.

Water Core. — Water core is an orchard trouble that develops in fruit
ripening on the tree. It is recognized by hard, glassy, water-soaked areas,
usually near the core or main vascular bundles. In severe cases, however,
most of the flesh may be affected, and the symptoms may be visible at the
surface. Although found in many regions, water core is most severe in
those of intense heat and sunlight. It is associated with mature or over-
ripe fruit and is common in Yellow Transparent, Early Harvest, Jona-
than, Delicious, Stayman Winesap, Winter Banana, Arkansas, Winesap,
and Yellow Newtown. Partial control may be obtained by avoiding ex-
cessive exposure of the fruit to sunlight and by picking it before it be-
comes overmature. Where present in only a mild form, the trouble may

34 Plagge, H. H., T. J. Maney, and B. S. Pickett. Functional diseases of the apple
in storage. Iowa Agr. Exp. Sta. Bui. 329:1-79. 1935.

Bul. 425] Apple Growing 81

disappear in storage. Severe water core may shorten the life of the fruit
by rendering it more susceptible to internal breakdown.

Fungus Rots. — Numerous fungus rots may shorten the life of apples
in storage, but the most common and destructive is the blue mold rot
(Penicillium expansum). This attacks the fruit through the lenticels,
breaks in the skin, and soon produces soft, watery, light -brown spots of
variable sizes. These enlarge rapidly and produce small patches of whit-
ish spores, which soon become more numerous and change to the char-
acteristic bluish-green color, whence the name blue mold. Blue mold
occurs primarily in storage, and its development is hastened by a com-
bination of high temperature and high humidity. Handling of the fruit
in clean boxes and avoidance of skin breaks will do much to prevent rot
losses.

Freezing Injury. — Cold-storage warehousemen watch their storage
temperatures so closely that freezing injury rarely occurs. Before apples
are injured from this cause the temperature must drop to 29.5° Fahren-
heit or below and remain there for several hours. Moreover, even though
the flesh may contain some ice crystals the fruit may subsequently fail
to show freezing injury. Water-soaked bruises are not a sure sign of
freezing. Usually the best indications are the discoloration of the fibro-
vascular bundles and the threadlike fibres extending throughout the
flesh. This coloration may easily be observed in the cross section of frozen
apples provided freezing has not been so severe as to result in complete
discoloration. In extreme cases all the flesh may become either dry and
mealy or brown and water-soaked in appearance.

Such specimens as these may closely resemble those in the advanced
stages of internal breakdown. Unless the fruit is known to have been
subjected to freezing temperatures, the trouble is difficult to identify
with certainty. Apples that have been only slightly frozen may be thawed
out with little aftereffect. Frozen apples, however, should not be handled,
for any bruising may result in soft watery areas, frequently extending
deep into the fruit. The conclusions of different investigators as to the
influence of the rate of thawing upon the amount of damage have not
been consistent. Perhaps, however, most of the evidence agrees with the
popular opinion that less injury is likely to occur where frozen apples
are thawed at a temperature below 40° Fahrenheit.

82 University of California — Experiment Station

SHIPPING AND MARKETING OF FRESH APPLES35

Seasons and Markets. — Early-summer varieties of apples and others
picked green to supply a limited local demand for cooking apples move
to market in June. The Gravenstein immediately follows in July and
August. This variety is packed and shipped east in refrigerator cars.
Considerable quantities are also loaded on vessels in San Francisco for
English and South American markets. Total shipments vary consider-
ably in different years, the annual average being about 1,200 cars.

The Yellow Bellflower variety supplies local markets from September
until November or sometimes later, whereas the Yellow Newtown finds
its best sale from December to April. Some of the latter variety is packed
and fills a demand of the English trade. The bulk of the crop, however,
as well as all the Yellow Bellflowers find their best market within the
state. Practically all the fruit moves by truck.

Methods of Sale. — Methods of sale vary considerably in different dis-
tricts. They may, however, be divided into personal sales and sales made
through various selling organizations. Personal sales include (1) sales
in which the grower deals directly with local dealers or consumers, (2)
sales to cash buyers or representatives of marketing organizations, and
(3) orchard sales to buyers who estimate the crop and offer a lump sum
for the fruit on the trees.

Selling on local markets, especially those near large cities, is desirable
where there is sufficient demand and the grower has the time and inclina-
tion to make his own contacts. This personal method is now followed by
numerous Watsonville growers, who not only produce their own fruit
but specialize in its marketing. A more simple method is to sell at the
orchard to cash buyers, who may do their own handling and in some in-
stances their own picking, cleaning, and grading. A certain price may be
agreed upon for a definite quantity of a given grade, or the entire crop
may be sold orchard run. In the Watsonville district the latter method
is popular ; not infrequently sales may be made some time before harvest
merely by estimating the size of the crop.

Though such sales relieve the grower of all the details of marketing,
they are not without their disadvantages. In years of a large crop, cash
buyers may be relatively few, and the price low. Buying on crop-estimate
basis is so risky that the buyer is justified in making only a low offer.

35 For details of marketing and distribution of apples see:

Stokdyk, E. A., H. E. Erdman, Charles H. West, and F. W. Allen. Marketing Cali-
fornia apples. California Agr. Exp. Sta. Bui. 501:1-151. 1930.

Park, J. W. Market distribution of car-lot shipment of fruits and vegetables in the
United States. U. S. Dept. Agr. Tech. Bui. 445:1-30. 1934.

Park, J. W., and E. R. Pailthorp. Marketing apples. U. S. Dept. Agr. Tech. Bui.
474:1-82. 1935.

Bul.425] Apple Growing 83

A further disadvantage of having the buyer do the harvesting is that
pickers may be employed on a box basis and may damage fruit spurs and
limbs of the tree. In addition, grading and packing by such buyers does
not always advance the reputation of the district for a high-quality
product.

Where fruit is produced in large quantities for the general markets,
the average grower must depend upon some marketing agency, either
private or cooperative. These organizations have in the larger eastern
markets their own sales representatives, men thoroughly familiar with
market conditions and the general demands of the trade. Private sales
agencies may purchase the fruit outright or sell on commission. Cooper-
ately owned marketing associations cannot guarantee to the growers —
who are the owners — larger returns than might be secured through pri-
vate agencies, but they have numerous possibilities for making market-
ing more successful.36 Several such organizations operating their own
packing houses sell a large proportion of the Gravenstein crop.

DRIED APPLES37- 38

Importance. — Unlike most California dried fruits, dried apples are pro-
duced as a by-product of an industry that grows its crops primarily for
fresh shipment. However, as a secondary outlet, commercial driers have
utilized a substantial proportion of the California apple crop for a good
many years. Drying is the most important outlet for apples that cannot
be satisfactorily marketed as fresh fruit because of low quality, inade-
quate transportation facilities, or inadequate demand for fresh con-
sumption.

Although California ordinarily produces only 5 to 6 per cent of the
United States apple crop, it has contributed over 45 per cent of the
national total of dried apples in recent years. The dried output of the
state averaged about 11,000 dry tons during the years 1931-1935, utiliz-
ing approximately 36 per cent of the total apple crop of the state. The
dried output has varied from 9,000 to 13,000 tons in recent years, re-
quiring an average of about 80,000 tons of apples in its manufacture.

36 Erdman, H. E., Possibilities and limitations of cooperative marketing. California
Agr. Exp. Sta. Cir. 298:1-19. 1925. (Out of print.)

37 The paragraphs on the importance of the California dried-apple industry were
written by S. W. Shear, Associate Agricultural Economist, Giannini Foundation of
Agricultural Economics. The rest of this section on dried apples and those following
on canned apples and apples put up for bakers were contributed by E. M. Mrak,
Research Assistant in the Division of Fruit Products.

38 For additional information see : Caldwell, Joseph S. Evaporation of fruits. U. S.
Dept. Agr. Dept. Bui. 1141:1-62. 1923.

Cruess, W. V. Commercial fruit and vegetable products, p. 392-394. McGraw
Hill Book Co., New York City. 1924.

84 University of California — Experiment Station

The drying industry is largely centralized in the Pajaro Valley and
in the neighborhood of Sebastopol. In recent years these two districts
have each produced about the same quantity of dried apples. About a
decade ago the Pajaro Valley normally produced at least 60 per cent of
the total dried-apple output of the state. However, apple production in
that district has shown a downward trend, while the percentage of the
crop utilized for drying has also decreased. At the same time there has
been a marked upward trend in the production of Gravenstein apples
in the Sebastopol district, accompanied by a big increase in the tonnage
dried. As a result of these opposite tendencies in dried-apple production
in these two principal districts of the state, the proportion of the dried
output contributed by the Pajaro Valley has decreased, while the per-
centage from the Sebastopol district has increased.

Since about 1929 the Pajaro Valley has usually supplied about 50 per
cent of the state dried-apple output, the Sebastopol district roughly 45
per cent, and other areas, chiefly Mendocino and Humboldt counties,
only about 5 per cent of the total. The dried-apple output of the Sebas-
topol district has averaged about 5,000 tons during the past ten years,
that from the Pajaro Valley a few hundred tons more. Large crops to-
gether with depressed demand for the fresh fruit have resulted in about
one-half of the Gravenstein crop being dried in recent years. An even
larger percentage of the late apple crop of the Sebastopol district is dried.

Fruit Suitable for Drying. — Apples of almost any variety, size, and
condition may be used for drying. An attractive product, however, can
be secured only from suitable fruit. Exceedingly small apples are
expensive to prepare, produce a low-grade product, and may be better
utilized for other purposes. Apples of regular shape are preferred be-
cause they minimize labor and loss in peeling and trimming. A fine
texture also reduces preparation losses and gives a better appearance.
Yellow or green varieties are preferred to red, since traces of such skin
left on the fruit in peeling are less noticeable. The color of the flesh may
be either white or yellowish, trade preference on this point being divided.
Varieties that tend to hold their light color when dried are preferable to
those that darken rapidly.

Variety Preferences. — From the standpoint of drier operators the va-
riety preference is probably, in the order named : (1) Yellow Newtown,
(2) Rhode Island Greening, (3) Gravenstein, (4) Bellflower. This ar-
rangement includes, of course, only the more common drying varieties.
Others often used for drying are Pearmain, Jonathan, Wagener, Hoover,
and Rome Beauty.

Bul. 425] Apple Growing 85

The Yellow Newtown is perhaps the most extensively dried, gives the
largest yield per ton of fresh fruit, slices well without undue breaking,
dries with a uniform color, and holds its color well in storage.

Rhode Island Greening gives almost as large a yield as the Yellow
Newtown and produces large slices drying a golden yellow. Because of
its large core, however, core remains are more apt to appear in the fin-
ished product.

The Gravenstein is popular largely because its early ripening permits
the producer to take advantage of opening prices and start drying earlier
in the season. It dries a cream yellow but tends to discolor badly in
storage unless well sulfured. The yield per ton of fresh fruit is about 80
per cent of the yield secured from Yellow Newtown or Rhode Island
Greening.

Yellow Bellflower, a soft apple, when mature bruises badly in han-
dling. During preparation the slices break, and it is difficult to get a
large percentage of rings with power machines. This variety is better
adapted, therefore, and more popular for the production of quarters
than slices. The yield per ton is less than from Yellow Newtown or Rhode
Island Greening but is better than that from Gravenstein. The color is
light, but because of bruising of the green fruit it may not be uniform.

Preparation of the Fruit. — Peeling and coring are done by machines,
which may be either hand or power-operated. Experienced operators
accomplish more with the power machines, but beginners are apt to in-
jure the fruit by improper coring. Some operators maintain, further-
more, that power machines are not satisfactory for apples with a soft
texture or a large core. All machines require constant care and adjust-
ment for the size of the fruit being peeled. After peeling and coring, the
fruit always needs to be trimmed as it passes along the inspection belt.
Any skin left on the surface, any worm holes, decayed spots, bruises, or
other blemishes should be removed.

Cutting is done by machine after peeling and trimming. The fruit may
be cut into slices, quarters, sixths, eighths, or small cubes.

Sulfuring. — Sulfuring may be done either before or after cutting.
Sulf uring before cutting quickly arrests the tendency to darken ; and
since whole apples do not pack together, the sulfuring may be more uni-
form than in sliced and heavily piled fruit. It has the disadvantage, how-
ever, that the fresh surfaces exposed by subsequent cutting are somewhat
more susceptible to oxidation and darkening and that the workers in the
plant dislike to cut the fruit after sulfuring rather than before. If the
fruit is sulfured before cutting, the work is best done on moving-slat belt
conveyors passing through a sulfur chamber. The length of the sulfuring

86 University of California — Experiment Station

period is determined by the length of the chamber and the speed of the
belt. The fumes of burning sulfur are introduced from a stove placed
outside the chamber and should pass through the chamber in a direction
opposite to that of the fruit. To control the flow of fumes, forced draft
may well be used. The escape of fumes should be prevented.

Sulfuring after cutting permits of greater uniformity if the fruit is
quartered or cubed. Some driers dip the fruit in 2 per cent salt solu-
tion immediately after peeling to prevent discoloration before sulfuring.
Some convey the fruit for 10 to 15 minutes through a bath of 1% to 2
per cent sodium sulfite solution in place of sulfur smoke, though the
smoking is almost universally preferred. In sulfuring, the cut fruit is
placed on trays and exposed to the fumes in an ordinary sulfur house
where the sulfur is burned in pans, pots, or pits.

The quantity of sulfur used per gross fresh ton of fruit ranges from
1% to 5 pounds. Apples never contain sulfur dioxide in excess of the
legal maximum. In fact they do not easily absorb and retain sufficient
S02 to preserve their color during storage. The time of sulfuring varies
from 20 minutes to 1% hours. The texture does not break down from
exposure to the fumes as with apricots and peaches.

Evaporating. — All apples are artificially dried in either the natural-
draft drier or evaporator or the forced-draft type known as a dehy-
drator. The former is still most often used, although the latter is becom-
ing popular.

The kiln evaporator is the most common type of drier in use. In this
the fruit is spread on the slat floor to a depth of 6-18 inches or more, and
heated air from a furnace beneath is allowed to pass up through the fruit
and out ventilators at the top of the kiln. The air temperatures main-
tained .range from about 150° Fahrenheit in the initial stages to as high
as 175° when the fruit has been in the kiln about half of the time re-
quired. In the final stages drying temperatures over 100° are not advis-
able. Relative humidities in the exhaust air range from 90 per cent at
first to 35 per cent at the end of the drying period. The fruit is usually
turned two or three times during drying, which for slices will require
from 12 to 18 hours.

Air conditions in stack evaporators are similar to those in the kiln
evaporator, but the drying time is reduced to 4-8 hours by placing the
fruit on slat-bottom trays to a depth equal only to the diameter of the
slices. Instead of the fruits being turned as in the kiln evaporator, the
individual trays are shifted up or down during drying.

With tunnel dehydrators, in which the fruit passes through on shal-
low trays, dry air (relative humidity at the hot end 18-20 per cent) is

Bul.425] Apple Growing 87

heated to 160°-165° Fahrenheit and passes over the fruit at the rate of
600 to 800 feet per minute. The usual time required for drying with this
type of equipment is less than in the ordinary type of evaporator.

Fruit is usually considered sufficiently dry when a handful of slices
pressed firmly together has an elastic, springy feel and separates at once
when pressure is released. Federal regulations require that the moisture
content of dried apples shall not exceed 24 per cent, while the standard
of the Dried Fruit Association of California is 22 per cent. It is cus-
tomary to pack apples with a moisture content close to those limits ; but
as some moisture must be added in the packing process, the fruit should
be dried to below 22 per cent.

After removal from the evaporator or dehydrator, the fruit is placed
in a large pile in a curing room, where overdry pieces will absorb mois-
ture and those containing too much will lose their surplus. The entire
mass should be turned each day or so, to insure uniformity. After this
condition is reached, the fruit is ready for grading and packing. Differ-
ent varieties of apples should be segregated since they require different
times for cooking and since differences in color of the flesh reduce the
uniformity of appearance.

Grading and Packing. — Individual growers doing their own drying
usually deliver their apples in sacks to those operating commercial evapo-
rators, to marketing associations, or to others equipped for grading and
packing. The fruit is reprocessed by adding moisture and resulfuring ;
is then segregated into grades39 according to size, color, and freedom
from blemishes ; and is packed in 25 and 50-pound boxes. The fruit is
put in from the bottom side of the box, the first layer being sealed and
placed by hand so that when the top of the pack is exposed it will have
an attractive face. After this first layer is placed, the rest of the package
is simply filled with loose fruit, which is packed in until the required
weight is secured.

California Evaporated-Apple Grades. — The grades by which Cali-
fornia dried or evaporated apples may be classified are Fancy, Extra
Choice, Choice, and Standard.

Fancy apples must be slices from sound, mature, large fruit. The color
should be extra bright and uniform for the variety, and different varie-
ties of different color should be kept and boxed or sacked separately. The
apples should be free from decay, mold, and worm-eaten blemish, and
should contain only a low percentage of other defects, and screenings.
There should be a high percentage of ring apples.

39 Grades for California evaporated apples may be secured from the Dried Fruit
Association of California, 1 Drumm St., San Francisco, California.

88 University of California — Experiment Station

Extra Choice apples must be slices from sound, mature fruit of
reasonably uniform medium or large size. The color must be bright and
uniform for the variety, and different varieties of different color should
be kept and boxed or sacked separately. They should be practically free
from blemishes, foreign matter, cores, skin, and screenings. Pieces show-
ing green skin should be few ; those showing red skin, even fewer. The
quantity of screenings should be low, but may be greater than that tol-
erated in the Fancy grade. The tolerance for core damage, too, is greater ;
and the percentage that should be rings is smaller.40

Choice apples should be slices from sound, mature fruit of large,
medium, or small size, reasonably free from blemishes, cores, and skin.
Though at present no objection is made to lack of uniformity of color,
the color must be characteristic of the variety. The tolerance for pieces
showing skin, for the quantity of screenings present, and for core dam-
age is more lenient than for the Extra Choice grade.

Standard apples are slices conforming to the United States Govern-
ment and California State Pure Food Regulations but not meeting the
requirements of Choice.

Quartered apples may be apples cut in 3, 4, or 6 approximately equal
pieces. Grade specifications are the same as for the corresponding grades
of sliced apples as to size, quality, color, separation of varieties, and
workmanship, excepting that the Fancy, Extra Choice, or Choice quar-
tered apples must be free of screenings. There is a relatively low toler-
ance on the presence of halves. Whole apples are not tolerated.

CANNED APPLES*1

Apples are canned extensively in the Pacific Northwest and the Eastern
United States, but seldom in California.

Canning is considered a by-product industry in most apple-growing
districts as a means of utilizing the best culls. Fruit for canning should
be fair-sized and as free of blemishes as possible. Acid varieties with
white, firm flesh are preferred. On the Pacific Coast the Yellow Newtown,
and Spitzenberg are popular.

In preparation for canning the fruit is first washed and graded, then
peeled and cored by machine. The peeled and cored fruit should then

40 Exact tolerances are not given because they vary from year to year and some-
times with the district. This information should be obtained from the industry for
any particular year.

41 For further details see:

Campbell, Clyde H. Campbell's book. 246 p. Canning Age Publishing Company,
New York, N. Y. 1930.

Cruess, W. V. Commercial fruit and vegetable products, p. 116-118. McGraw-
Hill Book Company, New York, N. Y. 1924.

Bul. 425] Apple Growing 89

be trimmed, quartered, and held in a 3 per cent brine to prevent darken-
ing. It is then treated to remove the oxygen by being (1) steamed at
180° Fahrenheit for 6 minutes, (2) held in warm water at 120° for V2 to
2 hours, or (3) subjected, while in warm water, to a 20-inch vacuum for
10 minutes.

After the deaeration treatment the fruit is packed into No. 10 cans as
solid pack, or a little boiling water or dilute brine is added. In most
cases, however, the solid pack is used. The cans should be filled at 150° to
160° Fahrenheit, exhausted 8 minutes in steam, and cooked (after seal-
ing) at 212° for 20 to 30 minutes. The exhaust for the wet packs is 3 to 4
minutes in steam, and the cook is 8 to 10 minutes at 212°. The exhaust
and time periods vary with the pretreatment and the size of can.

APPLES FOR BAKERS' USE AND OTHER APPLE PRODUCTS42

When preparing apples for bakers' use, the fresh fruit is peeled, cored,
and dipped in a 0.2 per cent solution of sulfurous acid for a few minutes.
It is then removed, sliced, and redipped. If a 0.2 per cent solution is
used the fruit must be submerged for 1 hour in order to retain a white
color. In a 0.3 per cent solution a 10-minute dip will suffice.

Fruit treated in this manner may be distributed to bakers for imme-
diate use in making fresh-apple products or may be packed in cans and
frozen for future use. In either case it retains a desirable light color.

Apple products produced on a lesser scale than those named above
include canned apple sauce, vinegar, cider, and brandy.43

STANDARDS OF APPLE PRODUCTION COSTS"

Standards of cost per acre and per box of producing Gravenstein apples
in Sonoma County and late apples in Santa Cruz County are shown in
tables 6 and 7. As will be noted, the detailed costs are divided into five
principal groups : labor, material, cash overhead and depreciation, and
interest. These data are based primarily upon records kept by apple
growers who cooperated with the Agricultural Extension Service for five
years in conducting apple enterprise-efficiency studies in the two coun-
ties. The studies indicate a wide variation existing between individual
orchards in production costs and management practices. These records

42 Detailed information may be obtained from the following reference : Joslyn, M.
A., and E. M. Mrak. Investigations on the use of sulphurous acid and sulfites in
preparation of fresh and frozen fruit for bakers' use. Fruit Prod. Jour. 12:135-40.
1933.

43 Apple pectin, which is not produced in California, is treated in : Booker, W. A.
Fruit pectin. 170 p. Avi Publishing Company, New York, N. Y. 1928.

44 This section has been prepared by B. B. Burlingame, Extension Specialist in
Farm Management.

90

University of California — Experiment Station

show that many growers could increase their net earnings by improving
practices.

The object here in presenting tables 6 and 7 is not to give so-called
"county averages" nor, on the other hand, ideal theoretical situations,
but rather to show desirable orchard-management setups that approxi-
mate actual conditions as found on the more profitable orchards in the

TABLE 6

A Standard of Costs for Production of Gravenstein Apples in a Mature
Orchard in Sonoma County, California*

Labor costs

Operations

Man

labor per

acre

Tractor

work per

acre

Truck

work per

acre

Cost
per
acre

Cost
per
box

Pruning

hours

35.0

3.0

3.0

7.5
28.5

1.5

1.5
4.0

hours

1.0

2.5
9.5

1.5

1.5
1.0

hours
3.0

1.0

dollars

10.50

1 75

3.15

4.37

16.63

1.72

1.73

2.80

cents
2 1

Brush disposal

0 4

0 6

Dormant spray

0 9

3 3

Disking two ways — turning under cover-

0.3

Disking or cultivating two ways— weed

control

Miscellaneous

0.3
0.6

Subtotal for early cultural operations

84.0

30.0
3.0

17.0

4.0
0.7

42.65

9.00
1.40

8.5
1.8

0.3

Subtotal for all cultural operations . . .

Picking 360 boxes from tree (at 9 cents) .
Picking 140 boxes from ground (at $1.50

117.0

108.0

16.0
14.0

17.0

4.7
11.0

53.05

32.40]

4.80 J
12.45

10.6

7.4

Hauling „.

2.5

138.0

11.0

49.65

9.9

Total labor costs

255.0

17.0

15.7

102.70

20.5

Material costs

dollars
8.00
2.50

12.68
2.00

cents
1.6

Dormant spray — oil and spreader $0.45 per 100 gal. = $2.25; rig operation $0.25. .
Other sprays (3) 62lA lb. lead = $6.88; 94 lbs. sulfur at $3.52; spreader = $1.33;
rig = $0.95

0.5
2.5

0.4

25.18

5.0

Carried forward

Bul. 425]

Apple Growing

91

TABLE 6— (Concluded)

A Standard of Costs for Production of Gravenstein Apples in a Mature

Orchard in Sonoma County, California*

Cash overhead costs

General expense, 5 per cent of total labor and material costs

County taxes

Machinery and equipment repairs

Compensation insurance

Total cash overhead costs

Total cash and labor costs (cumulative)

Brought forward

Depreciation

Depreciation on trees

Depreciation on buildings and improvements

Depreciation on tillage tools

Depreciation on spray rig

Depreciation on props and braces

Depreciation on ladders, lug boxes, picking bags, and miscellaneous

Total depreciation costs

Total cash, labor, and depreciation costs (cumulative)

161.75

dollars

cents

12.50

2.5

1.00

0.2

1.30

0.3

1.67

0.3

1.05

0.2

1.96

0.4

1948

3 9

32.3

Interest costs

dollars
12.50
1 00
0.38
0.62
0.40

0.44
12.50

cents
2 5

Interest on average value of buildings and improvements, $20 at 5 per cent . . .

Interest on average value of tillage tools, $7.60 at 5 per cent

Interest on average value of spray rig, $12.40 at 5 per cent

0.2
0.1
0 1
0.1

Interest on average value of miscellaneous and harvest equipment, $8.80 at

0.1

Interest on value of land, $250 at 5 per cent

2.5

27.84

5.6

189.59

37.9

* These data are based upon a 20-acre orchard unit of twenty-year-old trees, planted 70 per acre, with
a yield of 500 45-lb. boxes per acre of orchard-run fruit. Labor costs are computed with a wage rate of $0.30
per hour for man labor, and a total operating cost per hour of $0.85 for tractor, and $0.75 for truck.

county studies. They are intended to be used by growers as a basis of
comparison and also to help those not familiar with the costs involved
on good apple orchards in the two districts.

Most items of cost are self-explanatory except that of general expense
listed under cash overhead. This is computed at 5 per cent of the total

92

University of California — Experiment Station

labor and material costs and is included to cover miscellaneous expenses
such as interest on operating capital, use of the family car in connection
with the enterprise, telephone, and office. In establishing field-power
rates and depreciation and interest costs on equipment and facilities, an
orchard unit of 20 acres has been assumed. Field power supplied by a

TABLE 7
A Standard of Costs for Production of Late Apples in a Mature Orchard

Labor costs

Operations

Man

labor per

acre

Tractor

work per

acre

Truck

work per

acre

Cost
per
acre

Cost
per
box

Pruning

hours
60.0
4.0
1.0
1.0
8.4
31.5

1.5

1.5

4.0

hours

2.0
1.0

2.8
10.5

1.5

1.5
1.0

hours
1.0

1.0

dollars
18.00
2.90
1.15
1.05
4.90
18.38

1.72

1.73
2.80

cents
2 1

Brush disposal

0.4

Planting covercrop

0.1

Hauling and applying fertilizer

0.1

Dormant spray

0.6

2 2

Disking two ways — turning under cover-
crop

0.2

Disking or cultivating two ways — weed
control

0.2

Miscellaneous

0.3

Subtotal for early cultural operations .
Thinning

112.9

120.0
6.0

20.3

2.0
1.5

52.63

36.00

2.92

6.2
4.3

0.3

Subtotal for all cultural operations . . .

Picking 720 boxes from trees (at 6 cents) .
Picking 130 boxes from ground (at $1.50

238.9

144.0

15.3
30.0

20.3

3.5
22.0

91.55

43.20 1

4.59 J
25.50

10.8
5.6

3.0

189.3

22.0

73.29

8.6

428.2

20.3

25.5

164.84

19.4

Material costs

Fertilizer — 300 pounds commerical

Covercrop seed

Dormant spray oil and spreader $0.60 per 100 gal. = $3.36; rig operation = $0.28.

Other sprays (3) 75.6 lbs. lead at $0.11 = $8.32; spreader = $1.47; rig=$1.05

Miscellaneous material

Total material costs .

Carried forward

Bul. 425

Apple Growing

TABLE 7— (Concluded)

93

A Standard of Costs for Production of Late Apples in a Mature Orchard
in Santa Cruz County, California*

Cash overhead costs

Brought forward

General expense, 5 per cent of total labor and material costs

County taxes

Machinery and equipment repairs

Compensation insurance

Total cash overhead costs

Total cash and labor costs (cumulative)

dollars
9.49
5.00
2.00
1.70

18.19

208.01

0.6
0.2
0.2

24.4

Depreciation costs

Depreciation on trees

Depreciation on buildings and improvements

Depreciation on tillage tools

Depreciation on spray rig

Depreciation on props and braces

Depreciation on ladders, lug boxes, picking bags, and miscellaneous

Total depreciation costs

Total cash, labor, and depreciation costs (cumulative)

228.93

dollars

cents

12.50

1.5

1 00

0.1

1 30

0.2

1.67

0.2

2 00

0.2

2.45

0.3

20 92

2 5

26

Interest costs

dollars
12.50
1.00
0.38
0.62
0.75

0.61
15.00

cents
1 5

Interest on average value of buildings and improvements, $20 at 5 per cent. . .
Interest on average value of tillage tools, $7.60 at 5 per cent

0.1
0 1

0.1

Interest on average value of miscellaneous and harvest equipment, $12.20 at 5

0.1

1.8

30.86

3.7

259.79

30.6

* These data are based upon a 20-acre orchard unit of thirty-year-old trees, planted 70 per acre, with
a yield of 850 47-lb. boxes per acre of orchard-run fruit. Labor costs are computed with a wage rate of $0.30
an hour for man labor, and a total operating cost per hour of $0.85 for tractor, and $0.75 for truck.

light tractor and truck is most prevalent and practical on a unit of this
size. These figures should be considered as an average over a period of
years, since operations like pruning, fertilizing, and thinning will vary
from year to year.

To calculate harvesting costs per acre as well as costs per box, an aver-
age yield of orchard-run fruit for the Gravensteins was set at 500 boxes

94 University of California — Experiment Station

per acre of 45 pounds each ; for the late apples, 850 boxes of 47 pounds.
These yields correspond to those of the better orchards. Of the total
yield only 360 boxes of Gravensteins and 720 boxes of the late apples
were assumed picked from the tree, whereas the remainder of the crop
was harvested from the ground at a much lower cost. Attention is called
to the fact that some of the tree-picked fruit will be culls not sold as
boxed apples. The net cost of producing a so-called "packed box" could
be calculated by deducting from the total cost the income from cull
apples and those picked from the ground, which were disposed of for
other purposes, and dividing this figure by the actual number of packed
boxes. It is well to point out that high yield per acre is by far the most
important factor in obtaining low-cost production.

Where irrigation is practiced, in the Santa Cruz district, costs for this
operation will have to be added in table 7. Such costs would be justified
only by sufficient increase in production to offset them. This problem
must be solved by the individual grower.

A maximum cost of bringing trees into bearing was considered to be
$500 per acre ; and a productive life, forty years. Annual depreciation,
therefore, is $12.50 per acre. Interest has been figured on one-half the
average value of $500, or $250. Interest on improvements and equipment
is figured on the average values, or one-half the original cost.

YIELDS AND RETURNS

Differences in soil, climatic conditions, varieties, age of trees, and gen-
eral care given the orchards cause wide variation in apple yields.

The largest and mos# uniform yields are doubtless secured in the Pa-
jaro Valley, where the majority of orchards, under good care produce
average yields of 400 to 450 boxes per acre. From the better orchards
600 to 1,200 boxes may be produced. In the Gravenstein section of So-
noma County the general average yields of full-bearing orchards vary
from 250 to 450 boxes per acre, the size of the yield depending largely
upon the season. The more successful growers may secure 500 to 700
boxes to the acre. In both these sections, individual orchards in certain
seasons may give much higher yields, but these are exceptional.

In other sections, individual orchards will doubtless compare favor-
ably with these figures, although because of younger trees or the lack of
proper care the general average of an entire district will be lower. Even
in the best-producing sections there are orchards whose yields are ex-
tremely low, and only those on the better soils and under the best man-
agement will give satisfactory yields.

Average returns from the apple crop for the years 1926-1935 ex-
pressed as "farm value" are given in table 1. Figures of the Sebastopol

BuL- 425] Apple Growing 95

Apple Growers' Union show net returns on the Fancy grade of Graven-
steins for the ten-year period 1926-1935 to have averaged approximately
$0.75 a box. Net returns in different years have fluctuated from the ex-
tremely low price of $0.19 a box in 1932 to $1.58 in 1929. Windfalls and
other fruit not suitable for packing have usually sold at about $10.00
a ton.

Highly colored and well-graded winter varieties from the smaller sec-
tions at higher elevations return from $0.75 to $1.50 a box, according to
the individual variety and the amount of fruit available.

In the Watsonville section, where most growers sell their unpacked
crop to local buyers, returns during the years 1930-1936 have been from
$15.00 to $25.00 a ton45 for the Yellow Newtowns and from $12.00 to
$22.00 a ton46 for Yellow Bellflowers. On a box basis these prices may
appear not to compare favorably with those from other sections ; but the
figures are for the crop orchard run and involve no packing or selling
expenses. In determining actual net profit one must also consider the
larger average yields secured.

Although returns reflect the general condition of the industry, their
significance can be fully realized only by the grower who knows his
costs of production. High returns per box do not necessarily mean large
profits for low yields and extra cost for spraying, thinning, or marketing
affect profit regardless of price.

ACKNOWLEDGMENTS

The writer is indebted to the local Farm Advisors and Agricultural Com-
missioners in each of the apple-growing districts but, particularly, to
H. A. Weinland, E. A. Torpen and O. E. Bremner of Santa Rosa and to
Henry Washburn of Santa Cruz and Frank L. Kellogg of Watsonville
for their helpful information and for illustrations. E. C. Merritt, Man-
ager of the Sebastopol Apple Growers Union, J. R. Durbin, Manager of
the Gravenstein Apple Growers Cooperative Association and Carroll
Rodgers of Watsonville have supplied information regarding packing
practices and prices. R. E. Blair, Agricultural Statistician of the Cali-
fornia Cooperative Crop Reporting Service has furnished certain data
on acreages. S. S. Rogers, H. W. Poulsen and S. R. Whipple of the Cali-
fornia State Bureau of Fruit and Vegetable Standardization and Dr.
Alvin J. Cox, Chief of the Division of Chemistry have been helpful in
the preparation and in reviewing the sections on fruit standards and
on removal of spray residue. To all of these grateful acknowledgment
is made.

45 Approximately 55 boxes to the ton.

46 Approximately 60 boxes to the ton.

18w-6,'37