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Sample
spray schedules
for organic apple production in the Northeast
By Don Jantzi and Jeff Moyer

Below are three possible spray schedules based on our
experiences here at The Rodale Institute®
in Berks County, Pennsylvania. Sample #2 was the schedule
we used in 2003, and sample #1 is what we hope to do
in 2004.
NOTE: Our management decisions are
geared towards producing as large a quantity of grade
A table fruit as possible; growers with other objectives—such
as cider production—will want to make adjustments
accordingly.
Sample spray
schedule #1
Lime sulfur
and/or sulfur on scab-susceptible varieties beginning
at green tip.
Pyganic®
(pyrethrum) to control leafroller, plum curculio, fruitworm,
European sawfly, at pink and/or at petal fall.
Surround®
(kaolin clay), petal fall through June.
Entrust®
(spinosad) and Dipel®
(Bt) to control second generation codling moth, mid-July
or August.
Pheromone mating disruption
for codling moth and Oriental fruit moth, beginning
at bloom.
Sample
spray schedule #2
Lime sulfur
and/or sulfur on scab-susceptible varieties as needed,
beginning at green tip.
Surround®,
full season coverage beginning at pink or late bloom
and continuing as needed to maintain thick coating through
early August.
Sample
spray schedule #3
Sulfur as needed,
beginning at green tip.
Neem spray (Aza-direct®,
Neem oil, Agroneem®, or Neemix®)
as a fungicide for summer diseases and a summer insecticide
for various insects, at pink and/or petal fall.
Dipel®
and/or Entrust®
for internal worm, late summer.
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Resources
Guy Ames, Considerations in Organic Apple Production
(ATTRA Organic Matters Series, 2001)
Disease Management Guidelines for Organic Apple Production
in Ohio
www.caf.wvu.edu/
kearneysville/organic-
apple.html
Management Guide for Low-Input Sustainable Apple
Production
(jointly published by Cornell Univ, The Rodale Research
Center, Rutgers Univ, Univ, Univ of Massachusetts, Univ
of Vermont)
North American Fruit Explorers (NAFEX)
www.nafex.org
Stephen Page and Joseph Smillie, The Orchard Almanac:
A Seasonal Guide to Healthy Fruit Trees (agAccess,
1996)
Michael Phillips, The Apple Grower (Chelsea
Green, 1998) Note: Phillips is reportedly working on
a revised edition covering the latest materials, including
Surround. |
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May 11, 2004: The USDA Economic Research Service
tells us that in 2001 (the most recent year for which totals are available)
there were 12,189 acres of certified organic apple orchards nationwide,
up from 9,270 in 2000. But just 633.3 of those acres, or about 5 percent,
were east of the Continental Divide.
While Eastern and Midwestern states like New York, Pennsylvania,
Michigan, and Wisconsin have long histories of fruit growing and
strong—if struggling—apple sectors, growth in the organic
apple business has been largely restricted to Western states like
Washington, Arizona, and Idaho, where drier growing conditions translate
into drastically reduced pest and disease pressures.
Eastern fruit growers face twice as many problem diseases as their
Western counterparts (including fireblight, scab, black rot, and
cedar apple rust) in addition to no fewer than 60 species of damaging
insects. The single most destructive insect pest for Eastern growers—the
infamous plum curculio—is unknown in the West. The geographic
disparity is so great that Eastern tree fruit growing is widely
regarded as "the final organic frontier," as Michael Phillips
put it in his The Apple Grower: A Guide for the Organic
Orchardist (Chelsea Green, 1998).
If that phrase sounds like it contains a challenge—a throwing
down of the gauntlet for organic practitioners, it's because, well,
it does. Apple growers may seem like a soft-spoken bunch, but they're
stubborn, too; and their determination to find organic solutions
to Eastern production problems springs from a fierce loyalty to
the region, the work, and the way of life.
Eastern apples have more flavor than Western apples, declares Don
Jantzi, who grew up on a family apple farm near Buffalo, New York,
and has been orchard foreman for The Rodale Institute®
Experimental Farm since 1986. "Western soils tend to be sandier,
and those sandy soils give less flavor," he explains. Eastern
growers, moreover, have a broader range of varieties to choose from
than their Western counterparts, which means that "Eastern
growers tend to be more independent. Out West, the marketing programs
are so advanced that growers are more locked into a certain set
of varieties." And as anyone who's been to a supermarket lately
knows, those dominant Western varieties have grown steadily more
tasteless over the years as they have been further selected for
color, uniformity, and durability under shipment.
Pennsylvania State University fruit researcher Jim Travis goes
even further, arguing that what is widely regarded as the humid
East's greatest liability for organic fruit production—large
and vigorous insect populations—could eventually be seen as
its greatest asset. "Look at this biodiversity," he says,
gesturing at the rich spring scene, bumblebees staggering through
the air, green grass and dandelions and flowering trees bursting
out as far as the eye can see. "Western fruit producers are
growing in the desert. They don't have all this to work with."
The upshot is that despite the difficulties, Eastern fruit growing
remains viable. "If you have a good market for processed products—like
baby food, dried apples, juice, or sauce—or if you have a
good direct marketing strategy, like a pick-your-own operation or
farmstand," Jantzi says, "you can make it work."
Deep roots
The Rodale Institue Farm currently maintains about 1100 apple trees
on a total of just under six acres. The oldest trees here were established
in 1981, but the majority were planted in 1990, when an apple production
project was launched with support from the USDA's old Low-Input
Sustainable Agriculture (LISA) program (the precursor to the Sustainable
Agriculture Research and Education program, or SARE). That project
brought together researchers from Rodale, Cornell University, Rutgers
University, the University of Massachusetts, and the University
of Vermont, and yielded (among other things) an 84-page Management
Guide for Low-Input Sustainable Apple Production, which still serves
as a valuable reference for the running of the orchard today.

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After the research agenda wound down, a decision was made to continue
managing the trees for production purposes alone. "Our goal
was to maintain the orchard and to meet the challenge of staying
on top of new management strategies as they became available,"
says Jantzi.
Today, it looks like that strategy may be literally bearing fruit.
Evolving market conditions and new materials are making organic
apple production in the East more attractive than ever. And there
is now talk of initiating a new research agenda in the Rodale orchards
in collaboration with Pennsylvania State University (for more information
on that, click
here.)
Traditional management, with a few key differences
Many aspects of organic apple production would be perfectly familiar
to conventional orchardists. Organic managers adhere to the same
basic principles when it comes to selecting a site for a new orchard,
choosing rootstocks, pruning, and staking or trellising trees. "There's
an organic grower in New York who maintains that natural trees"—that
is, non-grafted, seedling trees, grown on their own rootstocks—"are
stronger and easier to keep healthy than regular grafted trees,"
notes Jantzi. Most organic growers, however, including The Rodale
Institute farmers, continue to work with grafted trees because they
are easier and less hazardous to prune, thin, spray, and harvest.
Independent of other factors, organic growers tend to favor wider
tree spacings in their orchards, and "may want to be more diligent
in their pruning," Jantzi says, since they need to rely more
heavily on factors like air circulation to reduce disease.
One area in which organic orchard establishment may differ sharply
from conventional practice is in the selection of varieties. Since
the mid-1980s, breeders have been releasing a series of disease-resistant
apple cultivars, including many that are resistant to apple scab
and others that show resistance to rust, fire blight, powdery mildew,
or fruit rots. Rootstocks, too, vary in their susceptibility to
certain diseases. While some growers reject the disease-resistant
varieties in favor of more recognizable—and therefore more
marketable—cultivars, Jantzi emphasizes that "there are
good scab-resistant varieties out there." Organic growers can
make their lives a little easier by including a handful of disease-resistant
varieties in their orchard mix.
"Good," it should be noted, is a strictly relative term
for apple growers, since there are so many qualities making up a
desirable apple, from tree maturation, growth habit, and blooming
period, to yield, fruit size, color, texture, flavor, and storage
characteristics. As any grower will tell you, successful orcharding
requires a combination of early, mid-, and late season varieties
both to spread out the risk of weather and pest susceptibilities
and to extend the marketing period over as many weeks as possible.
The Rodale Institute orchards include both scab-susceptible and
scab-resistant varieties; there are also a couple of heirloom varieties
that happen to be fairly scab-resistant, including Tydeman and Brown
Russet. Because of their research history, the trees here include
a wider assortment of varieties than most growers on this scale
would have: 39 altogether, from early-season cultivars like Lodi,
Jersey Mac, and Williams Pride to late-season favorites like Rome
and Granny Smith. "Some of the varieties we have I would not
plant again, but you work with what you have," observes Jantzi.

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The farm's younger orchard is dominated by three varieties: Liberty,
NY 74828-12, and NY 75441. Liberty is a Macintosh-type apple and
one of the most common scab-resistant varieties; Jantzi says it
tends to be pretty consistent in its fruit bearing, has a good red
color, and is good for both baking and eating fresh, but doesn’t
store particularly well. The two numbered varieties were obtained
on a research basis but were never released commercially and thus
were never assigned names. Nevertheless, Jantzi says they've proven
their worth on this particular site.
The orchard floor
"There's lots of debate about when and how much to mow,"
Jantzi says. "We mow fairly constantly through the growing
season, for aesthetic reasons, but some growers and researchers
argue that letting the grass stand under the trees encourages more
beneficial insects." On the other hand, Jantzi reports that
whereas in earlier years Rodale's orchard managers released packaged
beneficial insects, he no longer does this since beneficial insect
populations—including ladybugs, lacewings, honeybees, flies,
spiders, wasps, insidious flower bugs, predatory mites—are
now healthy without supplementation.
For additional weed management, Jantzi goes through with the Weed
Badger about four times a year, clearing an 18-inch strip along
the base of the trees. The aggressive cultivating tool is effective
but time consuming, Jantzi says, making weed management another
area in which organic growers have to spend more on labor than conventional
growers do.

To maintain fertility in the orchard, Jantzi puts down roughly
100 lbs of compost per tree per year ("Depending on who's doing
the shoveling," he notes). They used to spread in the spring,
but a few years ago switched to spreading in the fall, when the
compost can help the fallen leaves and waste apples decompose over
the winter.
A new generation of organic pest control materials
There's no way around it: pest and disease management are a big
part of orcharding in the humid East. Problem diseases include apple
scab, flyspeck, sooty blotch, powdery mildew, fire blight and cedar
apple rust, and the list of major insect pests is even longer, from
the plum curculio, to the oblique-banded leafroller, red-banded
leafroller, tufted apple bud moth, codling moth, Oriental fruit
moth, lesser appleworm, and European apple sawfly.
The cornerstone of low-input orchard management is good monitoring.
Each year, Jantzi hangs a series of insect traps in selected trees
to keep tabs on pest populations. The traps use pheromone lures
or visual and/or scent mimicry to attract specific pest species,
and can be used both to calculate the economic threshold at which
spraying is justified and to determine the optimum moment to spray.

"Most insects are most vulnerable at egg hatching stage,"
Jantzi explains, "so that's when you want to target your spraying."
It's also possible to anticipate pest cycles by keeping track of
degree days—the accumulated warmth (as represented by mean
daily temperature) above a 50°F base temp. Codling moth eggs,
for instance, will begin hatching 243 degree days after the first
moth is trapped. Of course, such calculations have to be balanced
by weather conditions when it comes to the actual spray schedule.
"You go for the ideal," as Jantzi puts it, "and then
you do what the weather will allow."
Pheromones are also used for active pest management in the form
of mating-disruption cards—small plastic cards which release
female insect sex hormone odors and thereby confuse the males as
they attempt to mate. Jantzi relies on mating-disruption to manage
Oriental fruit moths and codling moths. "They say that for
the pheromones to be effective you need a minimum orchard size of
5 acres, and your orchard should be as square as possible,"
he points out. The Rodale Institute orchards don't quite fit those
parameters, but Jantzi feels the cards offer the best solution for
handling these pests.
Probably the most radically new product for organic orchard management
is the kaolin clay product known as Surround®.
Developed in the late 1990s by two USDA Agricultural Research Service
scientists in cooperation with the Engelhard Corporation of Iselin,
New Jersey, Surround is based on what's called 'particle film technology.'
Rather than killing target insects, it forms a white, powdery film
on the leaves, branches, and fruits, making them unattractive or
unfamiliar to the insects. The idea was originally developed as
a possible disease-control mechanism; but researchers discovered
that while it had no effect on diseases, it was highly effective
against nearly all the major apple insect pests. There is also some
evidence that Surround increases net photosynthesis by keeping plants
cooler in the hottest part of the day.

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Jantzi and Jeff Moyer, Farm Manager at The Rodale Institute, made
frequent use of Surround in 2003, but were not totally happy with
the results—in part because last year's heavy rains made it
difficult to keep a coating built up. This year, they're planning
onconcentrating the Surround coverage within a shorter window, starting
about two weeks later and ending about six weeks earlier, and then
turning to other materials.
Other, relatively new, organic pest control materials Jantzi and
Moyer plan on trying in the coming season include spinosad (marketed
by Dow under the brand name Entrust®),
a fermentation product derived from a soil-dwelling actinomycete;
and some of the neem products like Aza-Direct®
(named from azadirachtin, the active ingredient extracted from the
seeds of the neem tree). "There are some studies that have
shown [Aza-Direct] to be effective, but others have found it not
to be effective," notes Jantzi. "People are still figuring
out the best ways to use these new materials." The New Hampshire-based
organic orchardist Michael Phillips has been experimenting with
the use of whole neem oil (as opposed to derived neem products),
on the grounds that it might be more effective and that it's economically
preferable to purchase the natural insecticide in a less processed
form, as close to the original producer as possible.
Most of these products can be tank-mixed, so if the timing is right
they can be combined to make fewer trips through the orchard. Part
of what's revolutionary about new materials like Entrust and Pyganic®
(a pyrethrum product) is that in contrast to most organic-approved
products, they work against a variety of pests. "That kind
of runs counter to organic thinking, where you're trying to minimize
impact on beneficials," Jantzi observes. But the new materials
are expensive, too, so growers are inclined to use them conservatively.
The bottom line
Acre for acre, apple yields can be as good in organic as in conventional,
Jantzi says, although they tend to be lower for a couple of reasons—the
lack of organic-approved growth regulators for thinning, and the
related tendency of varieties to fall into a biennial bearing habit.
The Rodale Institute farm orchards average around 600 bushels per
acre. A portion of the harvest is sold direct to the public through
The Rodale Institute bookstore, both pick-your-own and ready-picked.
The balance goes for processing, some sold wholesale for organic
cider and some custom-processed into apple butter for direct sale.
Jantzi is quick to point out ways in which the orchard set-up here
is far from perfect—the scale, for instance, is too small
for commercial independence, too large for the available labor.
He is intimately familiar with the challenges of apple growing and
the hazards of making the switch from conventional to organic management.
Although he draws inspiration from—and compares notes with—an
annual gathering of Northeastern organic apple growers, he still
says he knows "more people who have tried it and quit than
tried it and continued."
"I think every grower has it in the back of their mind that
they'd like to get away from using pesticides, but there are a lot
of things you have to consider," he cautions. It may make more
sense to think about gradual steps on the way to certified organic
production, Jantzi says, rather than an all or nothing approach.
Above all, "You have to educate yourself about what's possible,
both in terms of production and in terms of marketing." And
what's possible is expanding all the time. 
Laura Sayre is senior writer for The New Farm.
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