NYS IPM Field Crops Pest Report- May 16

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Black cutworm and True armyworm

There have been a few intense catches for black cutworm and true armyworm with our field corn pheromone-trapping network in western NY. The flight for both black cutworm and true armyworm in Seneca County (Seneca Falls) has hatched. You might see leaf-feeding for black cutworm but most likely no cutting yet. For true armyworms, the typical symptoms are feeding on the edge of the leaf and working their way to the midrib. The black cutworm flight in Monroe County (Rush) is laying eggs.  For management information on both insect pests, please view the following page.

Black Cutworm

https://cals.cornell.edu/field-crops/corn/insects-corn/cutworms

True Armyworm

https://cals.cornell.edu/field-crops/corn/insects-corn/armyworms

The is damage by armyworm on corn plants in the 2nd leaf stage. They feed form the edge of the leaf into the midrid

True Armyworm Damage

photo of Black Cutworm Damage

Black Cutworm Damage

2022 Interactive Pheromone Trapping Network Map on Black Cutworm and True Armyworm Flights




Black Cutworm Degree Day Accumulations from March 1 to May 16

*Location for Intense Catches

Black Cutworm

(Base 50)

Life Stage

Seneca Falls

Seneca County

April 26

25 Moths Caught

136

Leaf Feeding

1st-3rd Instar

Rush

Monroe County

May 15

39 Moths Caught

30

Laying Eggs

1st-3rd Instar

*Intense Catch is over 15 moths in a week.

True Armyworm Degree Day Accumulations from March 1 to May 16

*Location for Intense Catches

True Armyworm

(Base 50)

Life Stage

Seneca Falls

Seneca County

April 26

29 Moths Caught

 

136

Eggs Hatch

*Intense Catch is over 15 moths in a week.

Alfalfa Weevil

Alfalfa weevil activity has increased this week. There are a few reports from the Western New York Crop Management Association that alfalfa weevil are over threshold in some fields. It is time to scout fields and determine if your alfalfa is over threshold.

For more on alfalfa weevil please view the link to management information:

https://cals.cornell.edu/field-crops/forages/insects-forage-crops/alfalfa-weevil

This is a photo of Alfalfa Weevil Shot Hole Damage

Alfalfa Weevil Shot Hole Damage

Alfalfa Weevil Damage-There are many shot holes in the leaves of the alfalfa

Alfalfa Weevil Damage

 

Alfalfa Weevil Degree Day Accumulations from March 1 to May 5

Weather Station Location Alfalfa Weevil Life Stage
Arkport 224 Egg Laying
Bergan 246 Egg Laying
Ceres 246 Egg Laying
Corwin 219 Egg Laying
Gansevoort 263 Egg Laying
Geneva 268 Egg Laying
Highland 328 Larvae Feeding
Ithaca 293 Hatching
Kinderhook 266 Egg Laying
Laurens 284 Egg Laying
Malone 179 Egg Laying
Northport 321 Larvae Feeding
Peru 175 Egg Laying
Red Hook 287 Egg Laying
Versailles 287 Larvae Feeding
Watertown 196 Egg Laying

 

Alfalfa Weevil Life stage Development

Growing Degree Days for peak (50%) occurrence of stage

Stage of Life Cycle Degree Days *
eggs hatch 280
Instar 1 315
Instar 2 395
Instar 3 470
Instar 4 550
Cocooning 600
Pupa 725
Adult Emergence 815

*48 degree F base temperature

 

Cereal Leaf Beetle

There are more reports of cereal leaf beetle adults on small grains. There have been no eggs or larvae reported yet.

https://cals.cornell.edu/field-crops/small-grains/insects-small-grains

Cereal Leaf Beetle Eggs

Cereal Leaf Beetle Eggs

Cereal Leaf Beetle Larvae

Cereal Leaf Beetle Larvae

Powdery Mildew

There are a few reports that some fields of small grains have powdery mildew. This disease can really limit yield if it reaches high infestation rates. Please view the following page for more information.

https://cals.cornell.edu/field-crops/small-grains/diseases-small-grains/foliar-diseases

Powdery mildew on a cereal grain leaf.

Powdery mildew

Pea Aphids

Pea aphids have been found in alfalfa fields. Pea aphids generally do not cause yield losses due to the fact NYS has many natural enemies that control them. In recent years, we have had some fields that reach an economic threshold for this pest. For more information on pea aphids please view the following page:

https://extension.entm.purdue.edu/fieldcropsipm/insects/pea-aphid.php

This is a photo of pea aphids in a sweep net

Pea Aphids in Alfalfa