Scaffolds Fruit Journal, Cornell University NYSAES

Insects | Credits

Volume 6, No. 21						August 11, 1997


                                                    43°F      50°F
Current DD accumulations (Geneva 1/1-8/11):         2298      1537

Coming Events:                              Ranges:
Codling moth 2nd flight peaks                  1587-3103 1061-2212
Apple maggot flight peaks                      2033-2688 1387-1804
Comstock mealybug 2nd generation crawlers      2106-2768 1447-1924
San Jose scale 2nd flight peaks                2136-2591 1479-1874
Oriental fruit moth 3rd flight begins          2172-2956 1553-2013
Peachtree borer flight subsides                2230-3255 1497-2309
Spotted tentiform leafminer 3rd flight peaks   2415-3142 1728-2231
Redbanded leafroller 3rd flight peaks          2514-3225 1818-2625
Obliquebanded leafroller 2nd flight peaks      2634-3267 1789-2231

     Geneva: Codling Moth 2nd flight began 8/7.
             Spotted Tentiform Leafminer 3rd flight, Redbanded 
               Leafroller 3rd flight, and Obliquebanded Leafroller
               2nd flight all began today, 8/11.
             Apple Maggot numbers have increased.

TRAP CATCHES (Number/trap/day)
                                  7/28   7/31    8/4    8/7   8/11
Redbanded Leafroller               0.7    0.3    0.1    0.3    0.6
Spotted Tentiform Leafminer        665    183     45     12     67
Lesser Appleworm                   0.5    0.7    0.3    0.5    0.8
Oriental Fruit Moth (apple)        2.3    0.5    0.5    2.2    2.3
San Jose Scale                    23.2    5.8   15.4    3.7   22.8
Codling Moth                       2.3    1.3    0.6    2.5   17.4
American Plum Borer                1.7    4.0    2.4    1.5    1.8
Lesser Peachtree Borer             0.7    0.5    0.8    0.8    1.4
Peachtree Borer                    7.7    5.7    4.0    1.7      0
Obliquebanded Leafroller             0      0    0.3      0    0.4
Apple maggot                       0.3   0.08    0.2   0.08    0.4

Highland (Dick Straub, Peter Jentsch):
                                  7/14   7/21   7/28    8/4
Redbanded Leafroller               9.1    2.3    2.4    0.7
Spotted Tentiform Leafminer       59.7   46.0   28.4   43.5
Oriental Fruit Moth                1.3    0.3    0.6    1.2
Lesser Appleworm                   0.4    0.9    1.2    1.9
Codling Moth                       0.6    1.2    1.0    0.1
Fruittree Leafroller                 0      0      0      0
Tufted Apple Budmoth               0.4      0    0.4    0.1
Obliquebanded Leafroller           0.2    0.1    0.1    0.2
Sparganothis Fruitworm             0.7    0.1    0.3      0
Apple Maggot                       0.1*   0.9    1.1    0.9
Variegated Leafroller                0    0.4*   0.2    0.3
                                       		* = 1st catch



by Art Agnello
Entomology, Geneva

Before the crush of harvest activities closes in on us, now is a good time to take an almost-last look at the insect situation in your orchards, to help assure that the summer doesn't end with an unexpected sting when you thought everything was in good shape. Various weather irregularities always stir up potential trouble-makers, so you might make an informal accounting of what's going on with some of the following:

Apple Maggot

Catches have been light all around the region, but the first half of August is historically the time of peak flight, and a few sudden showers can come through to soften the soil and allow a fair proportion of the population to emerge. Be diligent in checking any traps you have out, and get a final cover spray on susceptible varieties if you're still catching sufficient numbers of flies.

Spotted Tentiform Leafminer

Although we're past the prime control window of 690-1150 DD (base 43°F) since the start of the 2nd flight, trees with more than 2 sapfeeding mines per leaf might still benefit from an application of a material such as Vydate or Provado, particularly to forestall the possibility of severe 3rd brood attack.

Sap feeding mine caused by early spotted tentiform leafminer instars on leaf underside

European Red Mite

Regardless of the low initial populations, the early summer heat generated healthy ERM outbreaks in various blocks, and bronzed trees are not unheard of. Particularly in view of the moisture stress evident in many orchards, a careful foliar inspection should be conducted, at least in your problem blocks, to be sure a rescue treatment of some sort isn't needed where populations surpass this month's 7.5/leaf threshold. Pyramite is available, among the regular standbys, so there's no excuse not to avail yourself of a remedy where needed.

Mite sampling chart

European Corn Borer

To repeat some words from an earlier issue, corn borer attack on young trees can occur from June through August. Damage to the fruit usually shows up in late summer, when the August flight of the bivoltine strain is active. Bearing orchards are more likely to show some early corn borer damage on the fruit if growers relax their spray program in June or early July. However, most fruit feeding occurs between the last cover spray (mid-August) and harvest. Weedy sites provide plenty of alternative hosts for this insect, especially those containing broadleaf dock, ragweed, pigweed, smartweed, and barnyard grass. Penncap-M, Lannate, and Lorsban can give very good control of ECB larvae, provided application is made before the caterpillars become concealed in the plant tissue. Potential problem plantings should be checked periodically in August for shoot infestations of this caterpillar, which is cream colored with a dark head.


Eggs of both clearwing species are still able to hatch and get into your stone fruit trees. American plum borer moths are at their 2nd generation flight peak and are also laying eggs. Therefore, it's not too late to treat orchards that are on a seasonal control program of trunk sprays: cherries - Asana, Lorsban, Ambush, or Pounce; peaches - add Penncap-M and Thiodan to the above list (do not spray fruit).

Older peach tree showing severe peachtree bore infestation and injury at soil level

Black knot in plum showing American plum borer frass

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:

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Photographs courtesy of New York State Integrated Pest Management Program