July 17, 2023

NYS IPM Weekly Field Crops Pest Report-July 17, 2023

Soybean Aphid (Aphis glycines)

Soybean aphids are present in fields but are remaining under threshold in most cases. Remember the threshold is an average of 250 aphids per plant and check 20 plants throughout the field.

The following is a guide on how to estimate the number of aphids on the plant by the University of Wisconsin:

https://soybeanresearchinfo.com/wp-content/uploads/2019/03/aphid_visual.pdf

For more information view the following website:

https://cals.cornell.edu/field-crops/soybeans/insects-soybeans/soybean-aphid

This is a photo of light green tiny soybean aphids on a soybean leaf

190 soybean aphids on leaflet

Potato leafhopper (Empoasca fabae)

Potato leafhopper are starting to increase in alfalfa. There are a few reports of them being over threshold in western NY. Remember when nymphs are present is when this pest causes the most damage. It is best to scout for potato leafhopper every 7 to 10 days.

For more information see below:

A Video on IPM for Potato Leafhopper in Alfalfa:

https://www.youtube.com/watch?v=8BIZYTq7Zec&list=PLE19BD8A62BE7D671&index=14&t=9s

Publication on Potato Leafhopper in Alfalfa:

https://cals.cornell.edu/field-crops/forages/insects-forage-crops/potato-leafhopper

A photo of potato leafhopper damage to alfalfa

potato leafhopper damage

Field Corn Pheromone Trapping Network

Western Bean Cutworm (Striacosta albicosta)

Western bean cutworm (Striacosta albicosta) and fall armyworm (Spodoptera frugiperda) are now being monitored. The pheromone trapping network has started to report low numbers of moths. Western bean cutworm will start to increase the last week in July through the first and possibly second week in August.  The western bean cutworm moths almost always lay eggs on pre-tassel corn. It is best to target these fields when out scouting for egg masses and first instar larvae. Remember once the larvae enter the ear of corn they can not be sprayed if they had been over threshold.

 

This a photo of Western Bean Cutworm Eggs (Photo by Mike Hunter-CCE)

Western Bean Cutworm Eggs (Photo by Mike Hunter-CCE)

Photo by Mike Hunter-1st instar western bean cutworm larvae

Photo by Mike Hunter-1st instar western bean cutworm larvae

This is a photo of western bean cutworm moths

Western bean cutworm moths

For more information view the following webpage: https://cals.cornell.edu/field-crops/corn/insects-corn/western-bean-cutworm