Insects | Credits

SCAFFOLDS Fruit Journal, Geneva, NY                             Volume 5 
Update on Pest Management and Crop Development                 July 15, 1996


43F 50F Current DD accumulations (Geneva 1/1-7/15): 1661 1095 (Highland 1/1-7/15): 2057 1366 Coming Events: Ranges: American plum borer 2nd flight begins 906-1876 973-1265 Oriental fruit moth 2nd flight peaks 1000-2908 577-2066 Lesser appleworm 2nd flight begins 1152-2302 778-1531 Obliquebanded leafroller 1st flight subsides 1420-2277 899-1546 San Jose scale 2nd flight begins 1449-1975 893-1407 Redbanded leafroller 2nd flight peaks 1479-2443 952-1698 STLM 2nd generation tissue feeders present 1504-2086 952-1201 Apple maggot 1st oviposition punctures 1566-2200 1001-1575 TRAP CATCHES (Number/trap/day) Geneva: 6/27 7/1 7/5 7/8 7/11 7/15 Redbanded Leafroller 0 0.1 0 0.3 0.2 0.5 Spotted Tentiform Leafminer 282 670 378 568 511 423 Oriental Fruit Moth 0 0.5 0.1 1.7 4.8 6.5 Lesser Appleworm 0 0 0 0.3 0.2 0.5 Codling Moth 2.0 13.6 10.6 6.7 1.7 2.6 San Jose Scale 0 0 0 0 0 0 American Plum Borer 1.0 0.6 0.1 0.5 0.2 0.4 Lesser Peachtree Borer (cherry) 0.2 0.1 0.6 0 0.2 0 Lesser Peachtree Borer (peach) 1.5 0.8 1.6 0.7 0.7 0.4 Peachtree Borer 9.8 7.6 4.9 5.2 2.5 0 Pandemis Leafroller 11.2 0.6 0.3 0.2 0.2 0 Obliquebanded Leafroller 0.2 0.1 0.1 1.0 0.3 0 Apple Maggot 0 0 0 0.2* 0 0.1 Highland (Dick Straub, Peter Jentsch) 6/10 6/17 6/24 7/1 7/8 7/15 Redbanded Leafroller 0 0 0.8 1.8 3.0 3.8 Spotted Tentiform Leafminer 1.8 55.1 24.4 1.7 33.9 38.3 Oriental Fruit Moth 1.4 0 0.6 0.4 0.9 0.5 Lesser Appleworm 0.1 0.9 0.9 0 0.2 0.1 Codling Moth 6.8 5.2 2.9 1.8 1.4 0.2 Fruittree Leafroller 0 0 0.1* 0 0 0 Tufted Apple Budmoth 0.6 0.8 1.6 1.0 1.1 0.9 Obliquebanded Leafroller 0.1* 4.9 1.8 2.4 2.6 0.4 Sparganothis Fruitworm 0.1* 0.5 2.0 1.8 0.9 0.3 Apple Maggot - - 0 0.2* 0.3 0.3 Variegated Leafroller - - - - 0 0.1* * = 1st catch Pest Focus Highland - DD (base 43 F) since 1st catch of Obliquebanded Leafroller (6/10 in Highland) = 953. Spotted Tentiform Leafminer 2nd flight started 6/17; DD (base 43 F) = 738. Geneva - DD (base 43 F) since 1st catch of Obliquebanded Leafroller (6/17 in Geneva) = 700. Spotted Tentiform Leafminer 2nd flight started 6/20; DD (base 43 F) = 627.


By: Art Agnello, Entomology, Geneva

Before and during apple harvest in recent years, a number of growers and fieldmen have been taken off guard by the appearance of neat little (2 mm) holes bored into the side of their fruit, similar in appearance to those caused by a stem puncture. Although some graders may be inclined to attribute this damage to apple maggot or European corn borer, cutting open these apples reveals a bright green worm, not feeding but lying inactive, in the burrow extending in from each hole. These are larvae of the dock sawfly, Ametastegia glabrata, a highly sporadic but nonetheless well documented apple pest that has been known to show up in our area since 1908.

Dock sawfly probably confines its feeding almost entirely to plants belonging to the buckwheat family (Polygonaceae), including numerous docks and sorrels, the knotweeds and bindweeds, or else wild buckwheat or alfalfa. In feeding on any of these plants, the larvae devour the leaf tissue and the smaller veins, eating out irregular holes in the leaves. Ordinarily, the midribs and the larger veins are untouched. This insect should not be confused with the related European apple sawfly, Hoplocampa testudinea, which has a whitish larva that lives and feeds in young apples, particularly prevalent in the eastern apple regions of N.Y.

Injury to apples by the dock sawfly is known to occur only in the late summer and early fall, when the fruit is approaching maturity and the sawfly is searching for an overwintering site. The greater hardness of immature apples probably deters the larvae from burrowing into these, so although 4 generations per year have been identified, only the last is of concern to apple growers. The injury to apples consists externally of the small round holes bored by the larvae, which after a few days show a slightly sunken, brownish ring around them and occasionally may be surrounded by a larger discolored halo. These holes may occur anywhere on the surface, but are most numerous around the calyx and stem ends, or at a point where the apple touches a leaf or another apple, since it is easier for the larva to obtain a foothold here. Inside, the injury is usually more serious, since the larva often burrows to the core and usually hollows out a pupal cell somewhat larger than itself. Apples may have three or four, or sometimes even eight, holes in them of varying depths, but contain only one or two worms.

Since the dock sawfly does not feed upon any part of the apple tree, but must live on the above-mentioned succulent weeds, it becomes an apple pest only where these plants are growing in or around the orchard. There is little danger from this insect in orchards where the food plants don't exist. Likewise, the possibility of the larvae coming into the orchard from neighboring meadows, ditch banks, or roadsides is slight, for the larvae are incapable of finding their way over any extent of bare soil. The adults, though active, are not strong fliers, and it is not possible for the insect to travel far in this stage. Now would be a good time to assess the weed situation in your orchard and make plans for such selective herbicide applications as may be appropriate regarding this insect. Even though common wisdom says this sawfly is a pest only every 12 years or so, this is only an average estimation, and it's not a bad idea to anticipate the unexpected in a season as atypical as this one has been.

(Information adapted from Newcomer, E. J. 1916. The dock false-worm: An apple pest. USDA Bull. 265, 40 pp.)


This perennial pest overwinters as a partially grown grub in the soil below the frost line. In the spring the grub resumes feeding, primarily on the roots of grasses, and then pupates near the soil surface. Adults begin to emerge during the first week of July in upstate N.Y., and judging from the reports and phone calls we've been receiving lately, they appear to be on schedule this year. The adults fly to any of 300 species of trees and shrubs to feed; upon emergence, they usually feed on the foliage and flowers of low-growing plants such as roses, grapes, and shrubs, and later on tree foliage. On tree leaves, beetles devour the tissue between the veins, leaving a lacelike skeleton. Severely injured leaves turn brown and often drop. Adults are most active during the warmest parts of the day and prefer to feed on plants that are fully exposed to the sun.

Although damage to peaches is most commonly noted in our area, the fruits of apple, cherry, peach and plum trees may also be attacked. Fruits that mature before the beetles are abundant, such as cherries, may escape injury. Ripening or diseased fruit is particularly attractive to the beetles. Pheromone traps are available and can be hung in the orchard in early July to detect the beetles' presence; these products are generally not effective at trapping out the beetles. Fruit and foliage may be protected from damage by spraying an insecticide such as Sevin or Penncap-M when the first beetles appear.

(Information adapted from: Johnson, W.T. & H.H. Lyon. 1988. Insects that feed on trees and shrubs. Cornell Univ. Press.; and Howitt, A.H. 1993. Common tree fruit pests. Mich. State. Univ. Ext. NCR 63.)


By: Harvey Reissig & Art Agnello, Entomology, Geneva

The injury caused by the second and third generations is identical to that caused by the first, but second-generation injury is most damaging to the tree. Third-generation STLM is usually not a problem if the second generation was controlled properly. Proper timing is essential for both the assessment of STLM densities and control, if required. If done too early, sampling will underestimate the population. If control is applied too late, it will not be effective. Sampling for sap-feeding mines should be done at approximately 690 degree-days (base 43F) after the start of the flight of the second generation. The second-generation flight began on June 17 in the Hudson Valley, and on June 20 in Geneva. If moth trap data or DD readings are not available in your area, you should be starting to sample for sap-feeding mines about now. Sampling guidelines can be found on pp. 81, 89-90, and 98 in the 1996 Tree-Fruit Recommendations. Although this procedure can sometimes require as many as three separate sampling sessions to properly determine the need for a treatment, the total time spent sampling a given block should not exceed 30 minutes. A decision regarding the third generation is generally not required unless the density of the second brood exceeded two mines per leaf. In recent years, approximately 8% of sampled orchards have required a treatment for second-generation STLM.

Several insecticides are effective against second-generation STLM, including Provado, Vydate, Lannate, and Asana. All of these products except for Provado are detrimental to predatory mites. Depending on the product chosen, application can be made anytime from initial egg deposition until larvae enter the tissue-feeding stages. Sampling is, of course, recommended before any spray is applied. If Provado is chosen, the manufacturer recommends aiming for the period 10-14 days after the flight starts. Unfortunately, if mines haven't yet begun to show up, this approach requires you to predict the need for a treatment based on either moth numbers or past field history, neither of which has been shown to be a very reliable indicator of actual pressure. According to our experience with this material, waiting until the appearance of early sap-feeding mines will give a better picture of problem blocks, and should still be timely enough to effectively manage economic populations. Regardless of when an application is made, we don't know ahead of time whether another spray will be needed, but considering the aphid and leafhopper potential in our region, a second application might eventually end up being elected anyway.


The OBLR developmental totals we've calculated as of this morning, 7/15, are given below; note that 720 DD marks the median development point (i.e., through fourth instar) of the earliest emerging larvae; at 810 DD, egg hatch is 90% complete, and at 950 DD, egg hatch is essentially over:

Highland - 953
Albion - 819.1
Sodus - 758.0
Lyndonville (with last 5 days estimated): - 729 
Williamson - 705.0
Appleton - 675.7
Geneva - 700


Plans are proceeding for the Fruit Field Day to be held at the N.Y.S. Agricultural Experiment Station of Tuesday, August 13, which is intended to update growers on the latest research and extension advances in tree fruits, grapes and small fruits. The field day will begin at 8:30 a.m. and end at 4:30 p.m. and is open to all interested fruit growers, consultants and industry personnel. Following is a more detailed listing of the day's program than the previously released version; some of the tour stops are still somewhat tentative, but the schedule is essentially finalized. A registration fee of $10.00 will be charged, which will include lunch. Advance registration is requested; contact Art Agnello at 315-787-2341 or


AUGUST 13, 1996

Registration 8:00 am - 9:00 am

Station Pavilion

Morning tour: 8:30 am - 12:00 noon

There will be two tour routes for the morning session (Hansen Farm and Loomis Farm). Each route will have 3 stops. Each bus will be a tour unit and will visit each stop sequentially at each farm. After completing one route each bus will return to the pavilion behind Jordan Hall for a juice break and then complete the second route.


20 min Hansen Farm 1) Traditional Fruit Grape Reisch, Breeding and breeding Henick- Enology Plots Kling 20 min Hansen Farm 2) Production Hansen 1 Robinson Systems TLR Plot 20 min Hansen Farm 3) IPM Area J English- Strawberry Loeb, IPM Plot Kovach 20 min Loomis Farm 4) Genetic Transgenic Aldwinckle, Engineering Plot Cummins, Norelli 20 min Loomis Farm 5) Physiology of Lakso O.34 Lakso, Grapes Pool 20 min Loomis Farm 6) Water and O.106 Stiles Nutrient Irrigation Management

Lunch Stop at Pavilion: 12:00 noon - 1:30 pm

There will be a tent set up next to the pavilion where manned displays from Food Science and PGRU will highlight those programs. After lunch either a federal or state legislator will address the audience.


Food Venture Center Anderson Continuous through lunch IR-4 Program Spittler Continuous through lunch PGRU Forsline, Lamboy Continuous through lunch Legislator Address Either Walsh 30 min at the end of lunch Sponsored by (representing NYS Hort Society Federal) or Kuhl (representing State)

Afternoon tours: 1:30 pm - 4:30 pm

There will be 3 concurrent commodity tours in the afternoon (Grapes, Small Fruits/Stone Fruits and Apples). Each commodity group will have 2 tours. Between each tour, the buses will return to Jordan Hall for a juice break. At that time, tour participants will be able to switch commodity tours. For these tours we envison presenters making the presentation only one time to however large a group chooses that particular tour.

Concurrent tours


1:30-3:00 Tour 1 Tour 1 (Small Fruits) Tour 1 3:00-4:30 Tour 2 Tour 2 (Stone Fruits) Tour 2

Individual tour stops are as follows:

Grape Tour 1


1:30-3:00 Research 1) Vineyard Management Research Pool, Lakso South 2) Vinifera Grape Research Pool, Henick-Kling 3) Breeding Reisch

Grape Tour 2


3:00-4:30 Robbins 1) Grape Pathology Research Wilcox, Gadoury, Seem Farm 2) Grape Breeding Reisch 3) Grape Entomology Research English-Loeb

Small Fruit Tour


1:30-3:00 Darrow 1) Biocontrol of Phytophthora Wilcox, Harman on Raspberries 2) Phytophth. Screened Sanford, Maloney Raspberry Seedlings 3) Raspberry 3rd Test Plot Sanford, Maloney with trickle & trellis 4) Day-Neutral Strawberries Rieckenberg on raised beds with trickle 5) Raspberrry Harvester Maloney (not confirmed yet)

Stone Fruit Tour


3:00-4:30 Research 1) Friday Peach Varieties Andersen North 2) Peach Rootstocks 3) Sweet Cherry Varieties and pruning 4) Bacterial Canker in Sweet Cherries

Apple Tour 1


1:30-3:00 Research 1) CG-Rootstocks Trials Robinson South 2) M.9 Rootstock Clones 3) Vertical Axis Tree Training 4) Trickle Irrigation and Fertigation Robinson, Stiles, Lakso 5) Apple Variety Breeding Brown

Apple Tour 2


3:00-4:30 Lucey 1) Orchard Systems Robinson 2) Mirid Bug Research Kain, Agnello Darrow 3) Yeast and Russetting of Apples Burr 4) New Developments in Research on Gadoury, Seem Apple Scab

Scaffolds is published weekly from March to September by Cornell University -- NYS Agricultural Experiment Station (Geneva), and Ithaca -- with the assistance of Cornell Cooperative Extension. New York field reports welcomed. Send submissions by 3 p.m. Monday to:

Scaffolds Fruit Journal
Editors: A. Agnello, D. Kain
Department of Entomology, NYSAES
Geneva, NY 14456-0462
Phone: 315-787-2341 FAX:315-787-2326

Back to the Scaffolds 1996 Directory
Scaffolds 1995 Directory