Facts for Fancy Fruit 96-04 April 10, 1996
 
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 Facts for Fancy Fruit is a newsletter for commercial and advanced amateur fruit
  growers developed in the Purdue University Department of Horticulture with
  regular contributions from the specialists in the Departments of Entomology and
  Botany and Plant Pathology, and from other agents & specialists on campus.  If
  you have questions, or are are interested in receiving this newsletter
  electronically, contact Bruce Bordelon (bb@hort.purdue.edu).
 ****************************************************

Inside:
 Crop Conditions
 Weather
 Fire Blight
 Apple Scab
 Nova, Rubigan & Tank Mixes
 Strawberries and Botrytis Fruit Rot
 Holding and Planting Fruit Trees
 Herbicides for Fruit Crops
 Honey Bee Colony Losses
 Grape Flea Beetle
 Mite Management
 Pheromones and Pheromone Traps
 Commercial Spray Guides Available on the Internet
 Pesticide Coordination Policy
 Coming Meetings/Events 

 Crop Conditions:  Plant development continues to be delayed almost two weeks
  behind normal across the state due to the below normal temperatures we have
  experienced this spring.  Apples are at silver tip to 1/2 inch green in the
  south, at silver tip throughout central part of the state, and still dormant in
  northern areas.  Peaches are at pink in the south and early bud swell in other
  areas.  Grapes are at early budswell in the south, and dormant in central and
  northern areas.  Blueberries are at full swell to bud break in the south, early
  swell in central areas and dormant in the north.  Strawberries are developing
  very slowly in most areas and growers have not yet removed straw.  
 
 Weather:  (From Purdue Crop and Weather meeting minutes, April 5) The dry trend
  persisted through the month of March with very dry conditions in the northern
  third of the state (less than 1/2 of normal) while precipitation in the central
  third was from 2/3 to 3/4 of normal.  The southern third of the state fared a
  little better with near normal precipitation.  Temperatures averaged 5 - 7
  degrees below normal for the month of March throughout the state.  The northern
  and central sections of the state averaged approximately 5 degrees below normal
  with the exception of west central which averaged just over 6 degrees below
  normal.  The southern third averaged just over 7 degrees below normal for
  March.  Over the last two weeks these trends persisted with temperature
  averages 3 - 5 degrees below normal statewide.  Precipitation amounts were near
  normal in the southern two thirds but remained well below normal in the
  northern portion. - Ken Scheeringa
 
 Weather Outlook:  (From Purdue Crop and Weather meeting minutes, April 5)
  Winterlike weather returned to Indiana over the past several days.  Portions of
  Indiana received snow flurries on April 6 - 8.  The 6 - 10 day forecast for the
  period April 9 - 13 indicates much below normal temperatures with temperatures
  as much as 12 degrees below normal north and below normal precipitation.  We
  should see a slight warming trend the 13th through the 15th.  There has been
  limited recharge of soil moisture levels in the last 2 weeks.  Subsoil moisture
  levels are limited in the north with levels in the central and south better. 
  Some parts of the south are showing some surplus moisture. - Tom Priddy, UK
 
 Fire Blight:  The late spring has significantly increased the potential for this
  to be a bad fire blight year.  Odds are now even higher that bloom will
  coincide with warm temperatures, and as you know, warm temperatures (daily
  average temperatures above 65¡F) accompanied by rain can result in severe
  blossom blight.  The best prevention for fire blight is the application of
  streptomycin during bloom.  Apply streptomycin just as blossoms begin opening
  and repeat every 3-4 days if weather favorable for blossom blight infection
  persists.  The "MARYBLYT" computer software program will help you in
  determining when and if an infection event occurred as well as predict the risk
  for future infection periods.  If you are interested in obtaining MARYBLYT 
  contact GemplerÕs at 1- 800 - 332 - 6744.
 
 Apple Scab:  The peak period for scab infection will occur within the next
  month.  Primary scab spores are ripe and ready to infect, all they need is a
  good scab rain.  Are you prepared?  For growers on a curative schedule, or for
  those who get caught with their pants down (unprotected), we suggest either
  Rubigan or Nova.  Both fungicides will provide up to 96 hours "curative
  activity".  However, the sooner you apply these fungicides the better!  Do not
  sit around thinking there is no need to rush - apply Rubigan or Nova as soon as
  possible after an infection period.  
 
 Nova, Rubigan & Tank Mixes:   If Nova or Rubigan have been used alone in your
  early season spray program for scab we suggest the final spray (petal fall or
  first cover ) of Nova or Rubigan be combined with a protectant fungicide such
  as captan, ziram, mancozeb, or Polyram.  Using a protectant fungicide at this
  time will provide protection from summer diseases such as black rot, sooty
  blotch and fly speck and help give added protection from fruit scab.  Refer to
  Rubigan and Nova labels for additional information on tank mixes.
 
 Strawberries and Botrytis Fruit Rot:  The most important sprays for control of
  Botrytis fruit rot of strawberry are those applied at bloom - starting at 10%
  bloom!  Rovral and Ronilan are excellent fungicides for control of Botrytis;
  however, resistance to these fungicides is a very real problem if they are used
  too often... follow label directions on frequency of spray applications.
 
 Holding and Planting Fruit Trees:  Just another reminder to get those trees
  planted as soon as possible so as to get them off to a good start in the
  season.  However, areas of southern Indiana are currently wet, and if planting
  must be delayed to get soil conditions right, then the trees should be stored
  carefully to hold them in the best condition prior to planting.  Most of
  northern Indiana is dryer than usual so planting can be done in a timely
  manner.
 	The best storage is, of course, refrigerated storage at 32¡F and high humidity.
   If you are using your apple cooler, be sure that there are no apples in it and
  that the cooler has been aired out to remove traces of ethylene.  An
  alternative is to heel the trees in on the north side of a building, or in the
  field, with the tops of the trees pointing 45 degrees to the south to minimize
  the effect of the sun on warming trees.  Be sure in any case to cover the root
  systems well with soil and to maintain adequate moisture on the tree roots.
 
 Herbicides for fruit crops:   Nothing beats knowing your problem weeds and
  aiming your program at the specific problem if possible.  If you have problems
  in identifying any weeds contact your county Extension educator.
 	If weed-free strips under tree rows are reasonably clean, then pre-emergence
  control materials can be used without the post-emergence materials.  This can
  result in substantial savings.  If weed or grass growth has already begun, or
  you are just establishing a weed-free strip, then a post-emergence material
  will be needed.  These materials are generally most effective when the grass or
  weed growth is 4-6 inches tall and growing rapidly.  Combine with a
  pre-emergence material for best weed control.  Consult ID 168 and ID 169 for
  suggestions on both pre- and post-emergence materials.  
 	Growers should not expect any herbicide to be effective year after year. 
  Treatment should be rotated through several herbicides or combinations of
  materials.  Be careful to follow label instructions on combinations.  The weed
  spectrum will change in response to the herbicide used and the grower should
  respond also with the best choice of herbicide for the new weed problem.  The
  product label is probably the best source of information on weeds that the
  product should control.  If the weed is not on the label the product will
  probably not control it.  Be careful to observe cautions and harvest
  restrictions just as you would with any pesticide.  Some herbicides cannot be
  used on bearing plants and some others require that plants be 1-3 years old
  before the material may be used.  Read ID 168, ID 169, and the product label
  carefully.
 
 Honey Bee Colony Losses:  Roger Hoopingarner of Michigan State University
  reports in MSU CAT Alert April 2, 1996 Fruit Edition that the winter of 1995-96
  may be the most severe in terms of bee colony loss on any on record.  In a
  fairly extensive survey the average winter loss was 62% in Michigan.  Many
  other northern states have similar losses.  These are probably due to the
  effects of parasitism by the varroa mite.  The prolonged periods of cold and
  the tracheal mites also added to the overwintering problem.  This level of loss
  should be of concern to all fruit growers.  In addition, there are two other
  factors that may impact the pollination situation.  The first is that southern
  package bee shippers are reluctant to increase their production to help replace
  bees.  The price of honey has increased dramatically and they want to use their
  bees to produce honey as well as bees.  Along with this lower package bee
  availability is the fact that honey bee colonies in the United States have
  declined more than 37% over the past 10 years.  The parasitism by the two mites
  and the very low price of honey over the past few years has taken its toll. 
  Beekeepers just could not afford to continuously replace colonies lost to mite
  infestations.
 
 Grape Flea Beetle:  Grapes are in the early swell to dormant stage across the
  state, depending on location and cultivar.  Development should progress rapidly
  over the next couple of weeks as temperatures climb above 50ûF.  Early to full
  swell stages are most likely to be damaged from flea beetles.  Scout vineyards
  for these insects or their damage and control if necessary.  Incidence often
  occurs in outer rows adjacent to fence rows or woods making spot spraying an
  option.  Scout the planting carefully and apply insecticides only where needed.
   Damage from flea beetles usually decreases as buds break and shoots become 1/2
  inch or longer.  Sevin or Penncap-M will provide excellent control of this
  insect.  Refer to the label or ID-169 for complete recommendations.
 
 Mite Management: The situation for managing mites in fruit crops, especially
  apples, seems to be changing almost daily because of the gain and loss of
  various pesticides. I will attempt to bring you up to date as much as possible
  in this article.
 	As you all know, last year Apollo was labeled for use on apples. This miticide
  can be applied no later than tight cluster. Our research results have shown
  that an application of Apollo will provide season long control of European red
  mites, as long as you conserve the predator mites. Using insecticides that kill
  the predator mites will likely result in a European red mite outbreak, even if
  you have used Apollo. A major concern with Apollo is the potential for
  development of resistance. As a result, I have recommended that Apollo be used
  on problem blocks only. Do not use Apollo on all your apples. We need to keep
  this valuable tool available for many years.
 	This winter, Savey was labeled for use on apples. Savey can be applied as late
  as pink. This product is similar to Apollo in its mode of action, level of
  control, and compatibility with conservation of predator mites. However, it
  appears that if mites develop resistance to Apollo, they will also be resistant
  to Savey, and vice versa. Therefore, Savey and Apollo cannot be applied in the
  same year. Again, Savey should be used primarily on problem blocks rather than
  on the entire orchard. Also, there is no reason to believe that you will not
  have a mite outbreak if you kill the predator mites, even if you used Savey.
 	One of our better foliar miticides, propargite (Omite), appears to be in
  serious trouble with the EPA as a result of residues and the potential for
  causing cancer. As a result, Uniroyal has decided to voluntarily cancel the
  registration of Omite on apples and nine other crops. Uniroyal will stop the
  sale of Omite immediately and will initiate a buy-back program for growers who
  have stocks of the product. 
 	Last week, Merck announced that Agrimek had received approval for use on
  apples. Apparently, the EPA hastened the approval of Agrimek because of the
  loss of Omite. Agrimek is an excellent foliar miticide which can be used as a
  rescue treatment when populations start to get out of hand. However, growers
  should be cautioned that mites can quickly develop resistance to most
  miticides, including Agrimek, if overused. Growers should continue to work hard
  at conserving their predator mites to reduce the selection pressure that could
  cause resistance to any of our miticides.
 	To sum up, I believe that apple growers now have the best tools available to
  control mites that they have ever had. Apollo and Savey are excellent early
  season products and Agrimek will clean up any later season problems. However,
  to keep these tools around for as long as possible, I suggest the following
  steps.
 
 ¥ 1. Use Apollo and Savey only on those blocks that have had a mite problem in
  the past and/or you expect will have a problem this year.
 
 ¥ 2. Use Superior oil sprays on blocks that are not treated with Apollo or
  Savey.
 
 ¥ 3. Conserve predator mites by spraying insecticides only when necessary and by
  choosing those insecticides that are least toxic to the predator mites.
  Specifically, growers should avoid using pyrethroid insecticides at any time on
  apples. Predators eat resistant as well as susceptible mites, so their feeding
  delays the development of resistance.
 
 ¥ 4. Monitor mites during the growing season and use thresholds to determine the
  need for foliar miticides. The general recommendations for thresholds are 2.5
  mites/leaf until June 30, 5.0 mites/leaf during July, 7.5 mites/leaf from
  August 1 through August 15, and 10.0 mites/leaf after August 15. If mite
  populations do not exceed the threshold, then treatment is not justified.
 
 ¥ 5. Consider using miticides other than Agrimek in appropriate situations. The
  other products may not be as effective as Agrimek, but several of them can
  provide economic control. 
 
 Pheromones and Pheromone Traps: One way insects communicate with individuals of
  the same species is with pheromones. Pheromones are volatile chemicals released
  by an insect that usually can be detected only by individuals of the same
  species. There are a number of different types of pheromones, but the most
  common type is the sex pheromone. Usually the females will emit a tiny amount
  of a chemical that attracts the male to her and increases the likelihood of
  mating. Because the chemical is volatile, it is carried by air currents. The
  male detects the pheromone in the air with receptors on his antennae.  He then
  flies upwind to find the source of the pheromone, a prospective mate. The
  chemical compositions of pheromones for a number of pest species have been
  identified and synthetic copies can be produced in the laboratory. Synthetic
  pheromones can be used in conjunction with traps to catch male insects.
 	There are a large number of fruit pests that can be monitored with pheromone
  traps. For growers who have not used traps before, I recommend starting out by
  trapping for codling moth and spotted tentiform leafminer. As you gain
  experience with the traps and learn how they can improve your pest management
  practices, you may want to begin trapping for additional pests.
 	There are two ways you can use pheromones. The first and most common method is
  to determine when the insect is active. This allows you to better time control
  practices or, in some cases, to determine if control is even necessary.
  Specific information for using pheromone trap catches to time insecticide
  applications for controlling spotted tentiform leafminer, codling moth, San
  Jose scale, and dogwood borer is available in the Midwest Tree Fruit Handbook
  (ID 60).
 	A more novel use for pheromones is known as mating disruption. Here the orchard
  environment is saturated with so much pheromone that the males are unable to
  successfully find a mate. Since the females are unmated, they do not lay eggs
  that hatch into the damaging larvae. The practice has been tested fairly
  successfully for Oriental fruit moth. The track record for using pheromones to
  control codling moths is not as strong, but it does show promise. I am not
  prepared to recommend these techniques at this time, because of the necessity
  for chemical control of other pest insects.
 
 Listed below are some, but certainly not all, of the suppliers of pheromones and
  traps.
 
 Consep Membranes, Inc.; P. O. Box 6059; Bend OR 97708; 503-388-3705
 Great Lakes IPM; 10220 Church Rd., NE; Vestaburg, MI 48891; 517-268-5693
 Insects Limited Inc.; 10505 N. College Avenue; Indianapolis IN 46280-1438;
 	317-846-3399
 Pest Management Supply Co.; P. O. Box 938; Amherst, MA 01004; 800-272-7672
 Scentry Inc.; P. O. Box 426, Dept. MPI; Buckeye, AZ 85326-0090; 602-233-1772
 Trece Incorporated; P. O. Box 6278. 1143 Madison Lane; Salinas, CA 93912;
 	408-758-0205
 
 Commercial Spray Guides available on the internet:  For those of you who donÕt
  have a copy of ID-168, Indiana Commercial Tree Fruit Spray Guide, and ID-169,
  Indiana Commercial Small Fruit & Grape Spray Guide, these publications are now
  available electronically.  You can access them at the following URL (address):
  http://www.agcom.purdue.edu/AgCom/Pubs/menu.htm
 
 Pesticide Coordination Policy:  The USEPA has issued a notice to explain and
  reaffirm its long-held policy, the pesticide coordination policy, of
  coordinating food safety regulations under FFDCA with pesticide registration
  under FIRRA.  This significantly impacts implementation of the Delaney clause. 
  This decision completes the USEPAÕs response to the 1992 Delaney-related
  petition by the National Food Processors and others which asked, in part, that
  the USEPAÕs policy of linking processed and raw food pesticide tolerances be
  discontinued.  In place since 1963, the coordination policy is designed to
  ensure that the lawful use of pesticides by farmers will not result in unlawful
  residues in processed food or feed.  As a consequence of this policy and the
  Delaney clause, some pesticide tolerances are expected to be revoked and the
  pesticide registrations on which they are based are expected to be canceled. 
  Last year, EPA conducted an economic impact assessment as to potential impacts
  on agricultural producers as a result of continuation of this policy without
  change.  The assessment concluded that the total economic impact on affected
  producers could be as high as $500 million.  Only three crops were estimated to
  incur impacts greater than 5 percent of their annual 1989-91 U.S. production
  value (Pineapple 29%, Sugarcane 13%, and Grapes 5.1%).  Absolute projected
  impacts were highest for sugarcane, grapes, potatoes, rice, and apples, which
  together comprised about 70% of total impacts projected.  For various reasons,
  however, the assessment was based on a worst-case scenario and actual impacts
  are expected by EPA to be far less.  EPA will update its economic impact
  analysis when it evaluates the remaining uses potentially affected by the
  Delaney clause.  For additional information contact:  Ms. Jean M. Frane, EPA,
  Policy and Special Projects, Phone 703-305-5944, Fax 703-305-6244, Email
  frane.jean@epamail.epa.gov  Source: Federal Register 61(7):2378  1/25/96
 
 
 Coming Meetings/Events:
 
 April 13 --- Madison Vineyards Opening. Contact Steve and Sandy Palmer at
  812-273-6500 or the Indiana Wine Grape Council at 800-832-WINE.
 
 April 26 --- Northeastern Indiana Fruitgrowers meeting.  6:-00 p.m. Meyer
  Orchard, 11061 E. 415 N., Kendallville, IN. Contact Rick Kemery at
  219-481-6826.
 
 June 19 --- Southeast Indiana Fruitgrowers Summer Tour. Apple Junction,
  Batesville, IN. Contact Karen Witt (317-647-3511) or John Ewart (812-926-1189).

======================================================================

Bruce Bordelon, 1165 Dept. of Horticulture, Purdue University, West
Lafayette, IN 47907-1165, 765/494-1298, e-mail: bb@hort.purdue.edu

Dick Hayden, Professor Emeritus, 1165 Dept. of Horticulture, Purdue
University, West Lafayette, IN 47907-1165, 765/494-1298, e-mail:
Dick_Hayden@hort.purdue.edu

Paul Pecknold, 1155 Dept. of Botany & Plant Path., Purdue University, West
Lafayette, IN 47907-1155, 765/494-4628, e-mail: Pecknold@btny.purdue.edu

Rick Foster, 1158 Dept. of Entomology, Purdue University, West Lafayette, IN
47907-1158, 765/494-9572, e-mail: Rick_Foster@entm.purdue.edu


Disclaimer:  Reference to products in this publication is not an endorsement
to the exclusion of others which may be similar.  Any person using products
listed in this newsletter assumes full responsibility for their use in
accordance with current label directions of the manufacturer.