home owners derive a great deal of satisfaction from growing their
own fruit. This endeavor, however, is not as simple as one might
hope. There are many insect and disease organisms, and pruning and
cultural management functions that must be considered in both planning
and maintaining a home orchard. Many problems can be avoided before
planting fruits. It is important to consider site selection, soil
fertility, size and type of plants, and especially varieties of
fruits, since they all relate to pest control. Many aspects of pest
control can be facilitated by the use of dwarf or semi-dwarf trees,
insect and disease resistant cultivars, and by purchasing plants
certified to be disease-free. Additional information on planting
fruits can be obtained from the Rhode Island Cooperative Extension
Introduction to Pesticides
Insect Trap Suppliers
Fruits can be attacked by many insect and disease organisms that
often require either insecticides or fungicides for control. These
chemicals can be purchased separately or mixed together as a multipurpose
fruit spray. A multipurpose fruit spray usually contains three pesticides:
Methoxychlor for chewing insect control, Malathion for sucking insect
control and Captan for disease control. The main problem with a
multipurpose fruit spray mix is that you may need a fungicide or
an insecticide at various times during the growing season, but not
both. This is especially true during bloom when you may not apply
an insecticide but a fungicide may be necessary. Insecticides cannot
be applied during bloom because bees are pollinating the flowers.
a result, you may want to purchase chemicals separately, since you
may not always need a fungicide when an insecticide is needed and
vice versa. Most of the insecticide recommendations are based on
phosmet (Imidan). The fungicides available to home owners include
Captan, Benlate, sulfur, fixed copper and Bordeaux mixture. See
notes on pesticides at the end of this bulletin.
To insure pesticides will work for you over the years, it is important
to prevent pests (insects and diseases) from becoming resistant
to chemicals. Pests develop resistance to chemicals most rapidly
when they are constantly exposed to the chemical. For this reason,
use pesticides only when necessary and at labeled rates. Benlate
is especially prone to resistance development, so you should use
Captan, Sulfur, fixed coppers or Bordeaux mixture whenever possible.
Pesticides are poisonous, therefore, applicators should be aware
of any hazards associated with pesticides they are applying. Take
appropriate steps to minimize exposure to yourself, neighbors, and
the environment. Although chemicals listed in this guide are relatively
low in toxicity to humans and warm blooded animals, safety measures
should be followed carefully. Keep pesticides in a locked cabinet,
away from children and pets. THE LABEL MUST BE READ IN ITS ENTIRETY
BEFORE SPRAYING! Particular attention should be paid to the antidote/treatment
in case of an accidental poisoning. Pesticide applicators should
avoid breathing mist or allowing mist to contact skin. If the label
instructs you to do so, wear protective clothing.
wettable powder formulations where possible, especially if pesticides
will be stored in an unheated garage during the winter. Do not store
pesticides at high temperatures (more than 86 degrees F) or allow
liquid formulations to freeze. Optimum storage temperatures are
between 65 and 80 degrees F.
Before spraying, learn the pests that may be present at various
times during the development of the fruit. It is also helpful to
learn insect and disease life cycles so you can time your applications
for optimum control. Identify damage to your fruit at harvest and
learn when to control the problem in subsequent years. You can tolerate
more damage to leaves by aphids, leafminers, mites and leafhoppers
than direct damage to the fruit. This is a general guide for pest
control for apples, pears, peaches, plums, cherries, apricots, blueberries,
strawberries, brambles and grapes. Your fruit may have additional
problems that need attention. To aid in identification of insect
and disease problems, contact the University of Rhode Island's Plant
Protection Clinic. For a small fee, an insect or disease problem
will be identified, and a control recommendation given. The address
is: Plant Protection Clinic, Greenhouse Conservatory, Cooperative
Extension Education Center, Kingston, RI 02881.
The first step in apple pest management is to plant trees that are
resistant to apple scab. This will eliminate the need to apply up
to eight fungicide treatments during the growing season. There are
many disease resistant cultivars available, such as Liberty, Freedom,
Macfree, etc. (see below for suppliers). Using disease resistant
trees, a dormant oil spray and sticky red spheres to catch apple
maggot flies, you can limit your pesticide sprays to two or three
applications per season. To control summer diseases (sooty
blotch and fly speck) you need to apply Captan or Captan/Benlate
starting in early June and continue every two to three weeks until
pink color is showing on flower buds
(DO NOT SPRAY INSECTICIDE
red mite eggs, aphid eggs, San
fall (when 90% of petals have fallen)
curculio, European apple sawfly, codling moth, leafroller,
green fruit worm
sticky spheres can control apple maggot flies without the use of
pesticides. Spheres should be placed within the canopy between 4-6
feet high. Use 1-8 traps per tree, depending on tree size (1 per
dwarf tree, 2-4 per semi-dwarf or 4-8 per full size standard tree).
Ideally, set out one trap for every 150 apples (see end of bulletin
for insect trap suppliers).
If the use of red sticky spheres for control is impractical because
of size or number of trees, the red sticky spheres can still be
used to monitor apple maggot fly activity for proper timing of an
insecticide application. One or two spheres per home orchard can
be used to determine presence of apple maggot flies. When 1-2 flies
per trap are captured, a half-rate spray of phosmet has been shown
to control apple maggot flies.
Resistant Apple Trees:
Liberty, Redfree, Nova-Easyro, Macfree and Jonafree are all resistant
to both apple scab and cedar apple rust. Make certain the cultivar
you choose is resistant to both diseases, since we have both in
Resistant Apple Tree Suppliers:
1. Hilltop Nurseries Inc., Hartford, MI 49057 616-621-3135 1-800-253-2911
Stark Brothers Nursery, Box B248CA, Louisiana, MO 63353 1-800-435-8733
Kelly Brothers, Dansville, NY 14337
Raintree Nursery, 391 Butts Rd., Morton, WA 98356 360-496-6400
Miller Nurseries, West Lake Road, Canandaigua, NY 14424 1-800-836-9030
Cummins Nursery, 18 Glass Factory Bay Rd., Geneva, NY 14456 315-789-7083
Rocky Meadow Orchard and Nursery, 360 Rocky Meadow Rd. NW, New Salisbury,
IN 47161 812-347-2213
Disease susceptible apple trees require the same insect control
as disease resistant trees. They also require use of a fungicide
to protect against apple scab. Captan or Captan/Benlate should be
applied as soon as green tissue is showing in April, and should
be applied every 7-10 days until the beginning of June. Continue
with Captan or Captan/Benlate every two to three weeks until mid-August
or early Sept. (depending upon cultivar harvest date) to protect
against summer diseases.
CAUTION - DO NOT MIX OIL AND CAPTAN, AS SERIOUS FOLIAGE INJURY
CAN RESULT. DO NOT USE CAPTAN WITHIN 7 DAYS OF AN OIL SPRAY.
with disease resistant trees, an insecticide may be needed at petal
fall and again 10-14 days later. Begin apple maggot fly control
at the end of June with red sticky spheres, or with half-rate phosmet
applications. Two or more sprays may be required for apple maggot
flies depending upon your cultivars and insect pressure.
Pears are relatively pest free compared to apples. Pears may require
a dormant oil application for pear psylla, an insecticide application
(phosmet) for plum curculio, and usually no fungicides for the entire
season. Pear psylla is the biggest insect problem because it is
resistant to most insecticides. Apply a dormant oil in early April
just as the flower buds begin to swell. Spray oil again 7-10 days
later. Apply an insecticide at petal fall if plum curculio is a
problem. Pears will occasionally have disease problems, but protectant
fungicide applications are not warranted unless you know you have
susceptible varieties, or are in an area with heavy disease pressure.
Early April (just
as buds begin to swell)
psylla, eriophyid mites
7-10 days later
(DO NOT SPRAY INSECTICIDE
The stone fruits may be difficult for the home orchardist to grow
because of a disease called brown rot, which affects the fruits.
Brown rot attacks all stone fruits (see GreenShare
Factsheet on brown rot for more information on this disease).There
are no disease resistant varieties available at this time. To aid
in the control of brown rot, remove and destroy all diseased and
mummified fruits after harvest and mulch in early spring with 3-4
inches of sawdust or other good mulching material. Blighted twigs
and cankers should also be pruned out. This will eliminate much
of the disease inoculum.
first fungicide spray for brown rot control should be applied just
before bloom when many of the pistil tips (stigmas) extend above
the buds. The number of sprays required during bloom varies from
year to year. Spray a fungicide every 4-5 days if damp, cool weather
persists through bloom. Plan on a total of three fungicide treatments,
just before bloom or early bloom, mid-bloom, and late bloom.
Black knot is another fungus of
plums and cherries. It affects twigs, branches and fruit spurs.
Prune out and destroy all diseased wood during late winter. Make
cuts 6-8 inches below any visible black knot swellings. Apply Captan
in the spring just before the buds open to control black knot or,
plant resistant cultivars. Of
the European varieties, Damson, Lombard, Shropshire and Stanley
are very susceptible. Bluefre is also susceptible. Bradshaw, Early
Italian, Fellenburg, Methley and Milton are moderately susceptible.
President is a resistant variety. Japanese varieties are generally
less susceptible than most American varieties.
are many insects that also attack stone fruits. Apply phosmet at
petal fall and again 10 days later.
(DO NOT SPRAY INSECTICIDE DURING BLOOM!!!)
bugs, stink bugs, plum curculio
Blueberries are perhaps the easiest fruit for homeowners to grow.
Blueberries generally require no insecticides or fungicides. The
blueberry maggot fly may need to be controlled with sphere traps
(see section on use of sphere traps for control of apple maggot
flies). One red or green sticky sphere baited with ammonium acetate
or ammonium carbonate placed within the canopy of each bush will
capture flies. Ammonium baited yellow sticky cards placed in a ÝV”
orientation over the canopy will also capture many flies. One other
problem with blueberries is that birds love them too. To keep birds
away place a net over the plants prior to the berries turning blue.
During years of high gypsy moth populations, an insecticide containing
Bacillus thuringiensis may be needed at petal fall.
When growing strawberries many problems can be avoided before planting.
Choose a site which was not recently planted in turf and has well
drained soil. Turf harbors many root grubs and root weevils that
may be troublesome to strawberries. Choose varieties that are resistant
to root diseases (verticillium, black root rot, and red stele),
and buy plants that are certified virus free. Renovate strawberry
beds yearly. In the fall, mow plants to 2-3 inches and rototill
between rows. Remove mowings and dispose of all old debris to remove
disease spores (do not compost). Avoid applying too much nitrogen
to strawberry plants. Apply fertilizers after harvest.
mold is a common disease that becomes visible on maturing fruit.
Many homeowners plant a few extra strawberries, figuring that if
some get grey mold, they will still have plenty of fruit. Using
this strategy, no fungicide applications are required. If you do
not mind spraying fungicides, grey mold can be controlled by applying
Benlate during bloom. If cool, rainy weather persists to prolong
bloom, plan on three fungicide treatments, early-, mid-, and late-bloom.
strawberry growers may need to apply one insecticide pre-bloom against
tarnished plant bugs, which feed
on strawberry buds and blossoms causing damage that results in small,
deformed, seedy berries. If you have had significant tarnished plant
bug injury in the past, apply one spray of malathion just before
the flower buds open.
(only if needed)
NOT SPRAY INSECTICIDE DURING BLOOM!!!)
(may need up to 3 treatments: early, mid and late bloom)
Cultivars Resistant to Red Stele:
Darrow, Delite, Earliglow, Guardian, Midway, Pathfinder, Redchief,
Redglow, Sparkle (Paymaster), Stelemaster, Sunrise, Lester, Scott
and Surecrop are resistant varieties. Not all of these cultivars
are resistant in all infested soils due to different strains of
Brambles are an excellent choice for the home grower because pesticide
treatments are generally not needed. The best prevention against
diseases and insect pests is a clean berry patch. Start with healthy
certified stock from dependable nurseries. Keep the canes thinned
out to maximize light penetration for photosynthesis, and air circulation
for disease control. Canes should be thinned to about 6-8 inches
apart. All old canes should be removed as soon as they finish bearing,
and the prunings should be destroyed (do not compost).
Brambles are shallow-rooted and thus poor competitors for water
and nutrients, making a mulch desirable. Straw or sawdust maintained
at a depth of 4-6 inches will retain moisture and suppress weed
growth. Weed control also improves aeration and reduces disease
occurrence. Avoid applying too much nitrogen.
are also susceptible to gray mold.
One or two fungicide applications may be needed to control this
disease. If it is a particularly wet bloom, three fungicide treatments
may be needed. As with strawberries, no fungicide treatments are
needed if you plant a few extra plants so you can tolerate some
fruit with grey mold.
(may need up to 3 treatments: early, mid and late bloom)
Growing grapes may be difficult due to several grape diseases. If
the growing site is located in a wet area with poor air circulation,
grape diseases can be troublesome. If on the other hand, the vines
receive good aeration, fungicide sprays may be reduced to two (or
fewer) per season depending upon the cultivar. To encourage good
air circulation, plant rows parallel to prevailing winds, remove
all weeds from around the vines, and keep vines well pruned. There
is also evidence that removing one leaf above and below the fruit
cluster can greatly reduce disease pressure. Planting varieties
that are less susceptible to grape diseases will also help manage
grape pests. Cascade, Dechaunac, Delaware and Ives are grape varieties
that are only slightly susceptible to black rot and botrytis bunch
is an important part of grape disease and insect management. Remove
and destroy all diseased clusters from vines at the end of the season.
Prune out old or diseased wood on the vines and rake all prunings
and leaves from beneath the trellis and destroy the material. Continue
to prune out diseased or injured fruit and foliage during the growing
season. Mulching or cultivating beneath the trellis will cover or
destroy any mummified berries lying on the ground. These berries
provide the black rot disease inoculum for spring infections. Powdery
mildew may develop during some seasons but it is not necessary to
apply preventative fungicides. If leaves become covered with the
white powdery fungus, a sulfur spray may be applied. Do not apply
sulfur to Concord or other sulfur-sensitive varieties.
insects attack grapes, but many of these can be removed by hand
during the growing season. Grape tomato galls can be removed and
destroyed when they are first noticed (mid-June). Berries infested
with grape berry moths can be pruned out and destroyed when the
grapes are forming. Another pest, grape phylloxera is an aphid-like
insect that forms galls on leaves and causes new leaves to curl.
Remove and destroy leaves infested with grape phylloxera. Japanese
beetles and rose chafers can also be removed by hand if especially
numerous. Grapes can tolerate a great deal of Japanese beetle leaf
feeding with no damage to grape cluster quality.
before bloom (when 5% of blossoms open)
or Bordeaux mixture
|Same as above
Same as above
||Methoxychlor (if 6% or more of grape
clusters are infested)
Gempler's IPM Buyer's Guide, 100 Countryside Dr., P.O. Box 270,
Belleville, WI 53508
Great Lakes IPM, 10220 Church RD NE, Vestaburg, MI
Ladd Research Industries, Inc., PO Box 1005, Burlington, VT 05402
Gardens Alive, 5100 Schenley Place, Lawrenceburg, IN 47025
information given herein is supplied with the understanding that
no discrimination is intended and no endorsement by the University
of Rhode Island Cooperative Extension Service is implied. The authors
have assembled the most reliable information available to them at
the time of publication. Due to constantly changing laws and regulations,
the University of Rhode Island can assume no liability for the recommendations.
(Superior) Spray Oil
Horticultural oils are used as dormant sprays to control scale
insects, aphid and spider mite eggs.
For control of many insects including aphids, spider mites, scale
insects, house flies, and mosquitoes. Malathion will also control
a large number of other sucking and chewing insects attacking
fruits, vegetables, ornamentals, and stored products.
AND STORAGE CAUTIONS: Harmful by swallowing, inhalation, or skin
contact. Avoid breathing spray mist. Avoid contact with skin.
Wash thoroughly after handling. Change contaminated clothing.
Biological activity of malathion remains practically unvaried
for 2 years in undamaged original containers in cool storage.
Recommended storage temperature 77-86 degrees F.
Widely used because of long residual action against many species
of insects and low toxicity to humans and warm-blooded animals.
HANDLING AND STORAGE CAUTIONS: Store in a cool, dry place.
APPLICATION/USE: Effective against a wide range of insects. Incompatible
with Bordeaux mixture and lime, but compatible with most other
pesticides. May cause severe leaf injury to sweet cherries. High
bee poisoning hazard.
Controls scab, black rot, botrytis, sooty blotch, fly speck, summer
rots on apples. Brown rot, leaf spots on stone fruits. Dead arm,
downy mildew, black rot on grapes. Controls wide variety of fungus
diseases on small fruits, berries, ornamentals, vegetables. Compatible
with most insecticides but cannot be used with oil sprays. Captan
has been listed by EPA as a probable human carcinogen. HANDLING
AND STORAGE CAUTIONS: Avoid contact with skin or clothing. Wash
hands and face thoroughly with soap and water after use and before
eating or smoking. Store in a cool, dry place. Persons entering
a treated area within four days following application must wear
APPLICATION/USE: Controls a wide range of diseases of fruit. HANDLING
AND STORAGE CAUTIONS: Do not contaminate water, food, or feeds
by storage or disposal. Keep benlate dry during storage to avoid
certain chemical changes affecting fungicidal effectiveness. Keep
container tightly closed when not in use. Benlate is toxic to
beneficial predatory mites, therefore, use only when alternatives
are not available. Fungicide resistance to benlate has been noted
where it has been used extensively. Benlate has been listed by
EPA as a possible human carcinogen.
THE FOLLOWING FUNGICIDES ARE PHYTOTOXIC UNDER CERTAIN CONDITIONS.
Bordeaux Mixture (hydrated lime + copper sulfate)
Primarily a fungicide, acts as a repellent against many insects.
Bordeaux mixture has a long residual action and has been used
for control of many fruit diseases, including black rot, downy
mildew, and powdery mildew of grapes. However, it has problems
with causing plant injury and due to the lime (high pH), it is
not compatible with many other pesticides. Bordeaux mixture is
generally unsafe to use on fruit crops after the 1/4 inch green
stage (New York State Pesticide Recommendations 1988). Bordeaux
mixture is prepared according to a three part formula (e. g. 2-6-100).
The first number is pounds of copper sulfate (not fixed copper),
the second number is pounds of hydrated lime, and the third number
is gallons of water. Bordeaux mixture is generally regarded as
safe as far as mammalian toxicity is concerned.
Copper (copper hydroxide, copper oxychloride sulfate, copper
tetra calcium oxychloride and tri-basic copper sulfate)
These formulations are referred to as "fixed" because the toxic
copper ion is relatively insoluble, making them safer than Bordeaux
mixture for use on fruit crops. However, the addition of spray
(hydrated) lime is still required to obtain the necessary degree
of safety for use on many fruit crops, depending on the time of
application. Fixed coppers are effective against many diseases
but are limited in use to certain sprays on grapes, pears, and
sour cherry because of injury to fruit and foliage. In general,
the fixed copper compounds are more compatible than Bordeaux mixture
with other pesticides. All fixed coppers are generally regarded
as safe as far as mammalian toxicity is concerned.
APPLICATION/USE: The most commonly used form of sulfur is the
wettable form. Wettable sulfurs are finely divided elemental sulfur
particles with a wetting agent added, allowing the sulfur to be
mixed with water and remain in suspension. The wettable sulfurs
are most readily available as dry wettable powders containing
95% sulfur or as fused bentonite sulfur containing 30% or 81%
sulfur depending on the brand. Flowable sulfur products are also
available. They have the advantages over wettable sulfur of being
effective at slightly lower rates, and having better retention
Dry wettable sulfur can be used with moderate effectiveness in
early season sprays for apple scab control. It may be used up
to and including bloom without substantially reducing fruit set.
Fruit russeting and reduction in yield may result if used under
high temperature conditions which often occur during post-bloom
Sulfur is very effective against powdery mildew of apple, cherry
and grape. Sulfur is used on stone fruits for control of brown
rot but has not been as effective as most other brown rot fungicides.
It also provides good control of peach scab, but is not effective
against Rhizopus rot. All sulfur fungicides are generally regarded
as safe as far as mammalian toxicity is concerned.
by Heather H. Faubert, Steven R. Alm, David B. Wallace, Richard
A. Casagrande and Lisa Tewksbury. Revised July 21, 2000