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May 3, 2004 Volume 13 No. 7 Update on Pest Management and Crop Development

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Coming Events

Coming Pest Events | Phenologies | Pest Focus | Trap Catches | Insects

Current DD accumulations
43°F
50°F

(Geneva 1/1-5/3):

309

160

(Geneva 1/1-5/3/2003):

266

135

(Geneva "Normal"):

286

132

(Geneva 5/10 Predicted):

380

196

Highland 1/1-5/3:

442

232

 

Coming Events:

Ranges:

 

Comstock mealybug 1st gen crawlers in pear buds

220-425

82-242

European red mite egg hatch

157-358

74-208

Green fruitworm flight subsides

170-544

69-280

Lesser appleworm 1st catch

135-651

49-377

Mullein plant bug 1st hatch

322-514

156-251

Obliquebanded leafroller larvae active

149-388

54-201

Oriental fruit moth 1st catch

129-587

44-338

Pear psylla 1st egg hatch

111-402

55-235

Plum curculio active

135-394

49-225

Rose leafhopper nymphs on multiflora rose

188-402

68-208

Spotted tentiform leafminer 1st flight peak

180-544

65-275

McIntosh at pink

258-320

113-170

McIntosh at bloom

310-448

152-251

 

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Phenologies

Coming Pest Events | Phenologies | Pest Focus | Trap Catches | Insects

(Geneva):

5/3

5/10 (Predicted)

Apple (McIntosh):

Early Pink

Bloom

Apple (R. Del.):

Early Tight Cluster 

Pink-King Bloom

Pear:

10% Bloom

Bloom

Sweet Cherry:

Bloom

Petal Fall

Tart Cherry:

Bloom

Bloom

Plum:

Bloom

Petal Fall

 

 

 

(Highland):    

Apple (McIntosh/Ginger Gold):

100% bloom

 

Apple (Golden Delicious):

20% bloom

 

Pear (Bartlett/Bosc):

full bloom

 

Sweet Cherry:

 early petal fall

 

Peach:

 petal fall

 

Plum:

 early petal fall

 

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Trap Catches

Coming Pest Events | Phenologies | Pest Focus | Trap Catches | Insects

TRAP CATCHES (Number/trap/day)
Geneva

4/22

4/26

4/29

5/3

Green Fruitworm

0.3

0.3

0.3

0.1

Redbanded Leafroller

1.7

1.4

1.7

15.8

Spotted Tentiform Leafminer

0.0

6.4

21.3

392

Oriental Fruit Moth

0.0

0.0

0.0

0.0

Lesser Appleworm

0.0

0.0

0.0

0.0

 

Highland (Dick Straub, Peter Jentsch):

4/12

4/19

4/26

5/3

Green Fruitworm

1.0

0.3

0.2

0.6

Redbanded Leafroller

0.4

3.3

7.6

11.6

Spotted Tentiform Leafminer

0.1*

19.9

34.4

172

Oriental Fruit Moth

0.0

0.1*

0.4

9.6

Codling Moth

-

-

-

0.0

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Pest Focus

Coming Pest Events | Phenologies | Pest Focus | Trap Catches | Insects

Geneva: STLM moth catches increasing

Niagara & Orleans Co.: 1st Oriental Fruit Moth catch on 4/30.

Wayne Co.: 1st Oriental Fruit Moth catch on 5/3

 

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Insects

Coming Pest Events | Phenologies | Pest Focus | Trap Catches | Insects

ORCHARD RADAR DIGEST

Geneva Predictions:
Roundheaded Appletree Borer
RAB adult emergence begins: May 31; Peak emergence: June 14.
RAB egglaying begins: June 9. Peak egglaying period roughly: June 29 to 13.

Lesser Appleworm
1st LAW flight, first trap catch expected: May 12; Peak trap catch: May 24.

Mullein Plant Bug
Expected 50% egg hatch date: May 15, which is 10 days before rough estimate of Red Delicious petal fall date.
The most accurate time for limb tapping counts, but possibly after MPB damage has occurred, is when 90% of eggs have hatched.
90% egg hatch date: May 24.

Obliquebanded Leafroller
1st generation OBLR flight, first trap catch expected: June 12.

Oriental Fruit Moth
1st generation OFM flight, first trap catch expected: May 3.
Optimum 1st generation first treatment date, if needed: May 22.

Redbanded Leafrolloer
Peak trap catch and approximate start of egg hatch: May 6.

San Jose Scale
First adult SJS caught on trap: May 19.

Spotted Tentiform Leafminer
1st STLM flight, peak trap catch: May 13.
1st generation sapfeeding mines start showing: May 18.
Optimum sample date is around Friday, May 24, when a larger portion of the mines have become detectable.

White Apple Leafhopper
1st generation WALH found on apple foliage: May 16.

Highland Predictions:
Roundheaded Appletree Borer
RAB adult emergence begins: May 21; Peak emergence: June 6.
RAB egglaying begins: June 1. Peak egglaying period roughly: June 21 to July 5.

Lesser Appleworm
1st LAW flight, first trap catch expected: May 1; Peak trap catch: May 13.

Mullein Plant Bug
Expected 50% egg hatch date: May 6, which is 8 days before rough estimate of Red Delicious petal fall date.
The most accurate time for limb tapping counts, but possibly after MPB damage has occurred, is when 90% of eggs have hatched.
90% egg hatch date: May 16.

Obliquebanded Leafroller
1st generation OBLR flight, first trap catch expected: June 2.

Oriental Fruit Moth
Optimum 1st generation first treatment date, if needed: May 11.
Optimum 1st generation - second treatment date, if needed: May 25.

San Jose Scale
First adult SJS caught on trap: May 7.

Spotted Tentiform Leafminer
1st STLM flight, peak trap catch: May 2.
1st generation sapfeeding mines start showing: May 6.
Optimum sample date is around Friday, May 13, when a larger portion of the mines have become detectable.

White Apple Leafhopper
1st generation WALH found on apple foliage: May 4.

 

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THREAT MATRIX
(Art Agnello & Harvey Reissig, Entomology, Geneva)

Apple arthropod pests during the early season are not particularly numerous, but they do require some form of strategy of attack to properly attend to the worst offenders and avoid wasting time on those under the radar. They include mites, rosy apple aphid, tarnished plant bug, and spotted tentiform leafminer. The key behind all of them depends, at least in part, on being familiar with your own orchards, and knowing whether a given block have a history of or susceptibility to a specific pest. Start with your knowledge of the block, use a sampling procedure where appropriate, and make a management decision.

Mites
If mites normally need attention in a given block, and you haven't elected (or been able to achieve) a delayed-dormant oil application as a part of your early season mite management program, you'll be needing to rely on either: one of the ovicidal acaricides (Apollo, Savey) available for use, whether before or after bloom; a rescue-type product (Nexter, Acramite, Kelthane, Carzol) that can reduce motile numbers later on if they should begin to lap at the threshold; or Agri-Mek, which falls somewhere between these two strategies. Like the true ovicides, Agri-Mek should also be considered a preventive spray, since it needs to be applied early (before there are very many motiles) to be most effective, generally within the first 2 weeks after petal fall. Also, as a reminder, Carzol is restricted to no later than petal fall, so it will probably be of limited use in most programs. For any of the rescue products, the operational threshold in June is an average of 2.5 motiles per leaf (see the chart in the Recommends).

Rosy Apple Aphid
Rosy apple aphid (RAA) will attack all apple varieties, but those such as Cortland, Monroe, R.I. Greening, Idared, and Golden Delicious are particularly susceptible, and those in the McIntosh family are relatively tolerant.

Our control recommendations for RAA cover the period from half-inch green to the pink bud stage, using any of a number of materials: Actara, Esteem, Thiodan, Lorsban, Lannate, Vydate, Supracide, Danitol, Warrior or Asana, listed roughly in order of increasing destructiveness to beneficial mites. Pink applications of any of these products should do just as good a job as an earlier spray. Generally speaking, in those cases where aphid populations have built up during early summer on vegetative growth inside the canopy, a pink spray will have done a more effective job of reducing populations than an earlier treatment at half-inch green. From the standpoint of management practicality, it is therefore easier and more natural to consider the need for aphid control at the time of the pink spray. Provado is an excellent RAA material, but it can't be applied earlier than petal fall, by which time much of the fruit damage this insect causes already will have been initiated.

RAA nymphs are of course present at pink, and large enough to see without difficulty, but they do occur on the same tree as, and in the midst of colonies of green apple aphids, which are not usually a problem until the summer. To distinguish among the species, you can use leaf damage as a cue, as well as the insects' color. RAA nymphs are usually pinkish, sometimes varying to a light brown, slate gray, or greenish black, and the body is covered with a whitish mealy coating. Most importantly, they have pronounced cornicles ("tailpipes"), and long antennae (more than half the body length). Green apple aphid nymphs are clearly green, and without the whitish cast. Their cornicles are little more than buttons, and the antennae are clearly less than half of the body length. Also, aphids found inside curled or distorted leaves at pink are almost always rosy apple aphids. If you find ONE infested cluster (1%, or stop as soon as you find one), we would advise including an RAA material in your pink spray.

Spotted Tentiform Leafminer
What else is happening at pink? STLM is laying eggs, but most orchards don't seem to suffer too greatly from 1st brood leafminer these days, and a sequential sampling plan can be used to classify STLM egg density at pink or of sap-feeding mines immediately after petal fall (see pink and PF charts in the Recommends). Treatment is recommended if eggs average 2 or more per leaf on the young fruit cluster leaves at pink, or if sap-feeding mines average 1 or more per leaf on these leaves at petal fall. Sampling can be completed in approximately 10 minutes. In recent years, only 1 out of 6 sampled orchards have required insecticide treatments to control first-generation STLM populations. Actara, Avaunt, or Vydate at pink, or Provado or Lannate at petal fall are our recommendations for this pest; Provado will also add to the leafhopper control if you don't use enough Sevin at thinning to do an adequate job. The pyrethroids -- Ambush, Asana, Danitol, Pounce and Warrior -- are also extremely effective against STLM, but use them in awareness of their detrimental effect on beneficial insects and mites.

Miscellaneous
Leafrollers are also out there, but only part of the population is active at this time, so it's better to wait for bloom or petal fall to address this one. Tarnished plant bug is the only real player left, and you'll have to decide for yourself whether this bug is of sufficient concern to you to justify treating. We have seen few orchards in western N.Y. where TPB control is warranted (slightly more so in the Hudson Valley), simply because the most effective treatment to use is still a pyrethroid, which a) kills predator mites, and b) still rarely lowers TPB damage enough to be economically justified. If you elect a spray of Ambush, Asana, Danitol Pounce or Warrior at pink for plant bug, you'll take care of rosy apple aphid (and STLM) at the same time; if rosies are your primary concern, scout for them first, and use Actara, Lorsban or Thiodan if you find any. Avaunt appears to have as much activity (i.e., moderate) against plant bug as Actara, but is not effective against rosy apple aphid.

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BEE HERE NOW
(Nick Calderone, Entomology, Ithaca)

Tree fruits, small fruits, and many vegetable crops, especially many of the vine crops, all require pollinating insects for a successful harvest. Remember! Not only is pollination important for a high yield, it is just as important to fruit size, shape and sweetness. A number of insects pollinate crops, but, for several reasons, the honey bee is the most versatile, all-around pollinator. Honey bees are available in large numbers throughout the growing season, they pollinate over 90 commercial crops, they are easily transported by truck, and they can be easily distributed throughout large plantings. Compared with other pollinators, honey bees are very cost effective. A single strong, two-story colony provides 15-25 thousand foragers.

How many colonies
Growers are usually concerned about the number of colonies they need to rent. New York growers have traditionally used about one colony of bees per three acres for apple pollination. This number may have been adequate in small orchards visited by feral honey bees and by solitary bees and bumble bees from adjacent hedgerows and woods. However, feral honey bee populations have been greatly reduced in recent years, and modern agricultural practices have eliminated many natural nesting sites for solitary bees and bumble bees. In addition, the flight range of solitary bees is not generally sufficient to ensure coverage of the center portions of large plantings. Growers with large blocks of apples and other tree fruits may wish to increase the number of hives to one per acre. If your fruit set has been lower than expected in the past, or your fruits are lopsided or misshapen, you probably need to use more bees. Remember, if your fruit set is too high, you can always thin, but if it is too low, you are just out of luck. Move bees into apples, regardless of variety, right as the king blossoms begin to open. Also, modern cultivars with high blossom densities, such as trellised apples, require more pollinators.

Special requirements
Most other crops are also adequately served by a single strong colony per acre. Some crops, however, have special requirements. Red Delicious apples have flower structures that are different from most other common varieties such as McIntosh. Their anthers are widespread, and bees learn to insert their mouthparts between the anthers to obtain nectar. Consequently, the bees do not contact the flower's sexual parts and pollination does not take place. Since it takes time for bees to learn to obtain nectar in this way, you can counteract this problem by using more colonies per acre to increase the number of inexperienced bees present. Up to two colonies per acre may be needed in large stands of Red Delicious apples.

Pollination of pears will probably always be a problem because pear nectar contains only about 15% sugar versus 40% for apples, dandelions, and yellow rocket. The answer is to move the bees into the center of the pear block when the pears are at 50% bloom. It will take some time for the bees to discover better sources farther away, and in that time, the pears may be adequately pollinated. An alternative is to use more colonies per acre, which will increase the number of bees foraging within the orchard.

Hive Placement
Always select good locations for the bees you rent to obtain maximum benefit for your pollination dollar. It's a lot like real estate -- location-location-location. A good location slopes slightly to the east or south, is protected from the wind, and has as much exposure to sunlight as possible. It is important that colonies of honey bees be kept in full sunlight in order to warm the hives rapidly in the morning and entice the workers out of the hives on chilly spring mornings. Entrances should face south to east, whenever possible. Keep colonies on pallets or cinder blocks to keep the bottom boards 3-6 inches above the ground. Hives with wet bottom boards will be cooler and have less foraging activity than dry colonies. A hive stand will also keep colonies above tall grass, which may shade or block the entrance. Place colonies in groups of 4--6 to take advantage of good locations. In large orchards and fields, groups of 10-20 hives can be used to take advantage of prime locations. It is best to locate hives near pollinizer rows where that consideration applies, such as with apples and sweet cherries.

Pesticides
Overall, pesticides are less of a problem to bees and beekeepers today than they were 10 and 20 years ago. Nevertheless, serious poisoning incidents still occur, and several reports of bee poisoning from methyl parathion were confirmed recently in NY. It is important to read the pesticide label and to avoid using materials that are especially toxic to bees whenever there is a safer alternative available. Sevin (carbaryl), Guthion (azinphosmethyl) and Penncap-M (micro-encapsulated methyl parathion, still labeled on several crops in NY) are especially toxic to bees.

Honey bees are most often killed by pesticides when they ingest contaminated pollen. However, bees can also be poisoned by pesticides that have contaminated small pools from which foragers collect water to dilute the honey they feed their young. Bees will collect water from the closest available source, including standing water in wheel ruts and old tires in or near your fields. A problem exists if more than 10 dead bees are found in front of a hive in the morning. If too many bees die, your crops will not be adequately pollinated and it may be necessary to rent more bees. You can help the bees by providing them with a source of clean water by the hives. A small tub with a few wooden floats will work well. A lathe-strip top from a bushel basket is ideal. If you don't provide floats, many bees will drown.

You can eliminate most pesticide damage to bees, both managed and wild, by not spraying when flowers, including weeds, are open and attractive to bees. Also, do not spray when there is any risk of drift to non-target crops or flowers. Evening, about an hour before sunset, is usually a good time to spray because there is generally little wind at that time. Always use the largest droplet size possible when spraying, and check out the use of spray stickers to help minimize drift. Keep flowering ground-cover plants mowed if you are going to spray in an orchard during the summer. Clover and dandelions are common problems for bees on orchard floors -- keep it mowed or use an herbicide.

General Recommendations
Bees should be moved onto location at night, and once the hives have been set down for pollination, you should leave them at that spot until the job is done. Moving bees in the daytime and moving them short distances (less than 3 miles as the crow flies) will cause a serious loss of foragers and seriously damage the colony. Always contact the beekeepers if the need arises to move the bees. If you live in an area with known bear problems, use an electric fence to protect the bees. Keep nearby flowering plants mowed to reduce competition for the bees' attention.

The Beekeeper
I recommend establishing good working relations with several beekeepers to ensure that you have a ready supply of bees for pollination. Any individual beekeeper's situation may change over time, but if you work with several beekeepers, you should always have ready access to an adequate supply of colonies.

Pollination fees
Beekeepers are just learning what many farmers have been aware of for many years -- pesticide resistance. Many beekeepers are finding heavier than normal winter die-off due to pesticide resistant parasitic mites. Look for rental fees in the $35-$60 range, depending on strength. Remember! The best deal may not always be the cheapest deal.

Expectations
Remember! Bees are an essential part of your crop production system, but they are only one part. In many ways, they are like the fertilizers and chemicals that you buy. Each is essential, but none of them, by themselves, can guarantee a crop. Many things influence the quantity and quality of your crop. One is the weather. Bees will visit flowers and pollinate only if they can fly. Cool, rainy, and windy weather will delay, slow, or stop flight, and the beekeeper cannot do anything about the weather. Excessive heat during the summer can cause problems with fruit set in certain crops, like pumpkins. Again, this is beyond the beekeeper's control. Be clear up front about your expectation concerning the strength of the colonies you rent and satisfy yourself that you have received what you expected. This will eliminate misunderstandings down the road.

TIPS:
Planning a new orchard? Be sure to determine if your main cultivars are self-sterile -- like McIntosh and Red Delicious apples -- or, worse yet, self-sterile and inter-incompatible like many popular cultivars of sweet cherries. If so, be sure to plant an adequate proportion of pollinizer cultivars. Be sure you select compatible pollinizers that bloom at the same time as your main variety. If you do not have pollinizers in your self-sterile stands, you can often purchase compatible pollen and use hive inserts to distribute it to the blossoms.

The price of honey has been significantly higher the past two years as a consequence of limited supply: there has been a downturn in production in Argentina, and imports from China have been restricted due to the presence of antiobiotic residues. Consequently, bees seem to be harder to come by than usual, as beekeepers seek the higher income from the increased honey prices. This could continue into next year, so it would be wise to start getting next year's contracts in writing as early as possible. You may find some demands for higher rental fees as a result of the higher honey prices.

 

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This material is based upon work supported by Smith Lever funds from the Cooperative State Research, Education, and Extension Service, U.S. Department of Agriculture. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture. Return to top