Cereal Leaf Beetle (Oulema melanopus)

Cereal leaf beetle adults are starting to show up in small grains fields. They seem to prefer oats but can also cause damage in wheat and other small grains. They are laying eggs on leaves. The following photo is what to look for when scouting small grain fields.

Cereal Leaf Beetle Eggs

Cereal Leaf Beetle Adult

This graphic helps better understand when to scout for the pest:

Cereal Leaf Beetle Lifecycle

For more information on Cereal Leaf Beetle:

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

Black cutworm (Agrotis ipsilon) and True Armyworm (Mythimna unipuncta)

There was only one new location with an intense catch last week. This was black cutworm in Dutchess County in Eastern NY. Larvae should be present in the next week or so from the early intense catches.  Make sure to get out and scout for the larvae feeding on corn. This is a nocturnal pest so it is best to look under the soil around the base of the plant or crop residue. When they get to the 4^th instar is when they start cutting plants. The threshold to control is when they reach 5% of the corn plants cut in the field. Your insecticide seed treatments are supposed to control this pest early in the season.

Information on Black Cutworm

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

Black cutworm damage to emerging corn

Information on True Armyworm

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

Field Crops Pheromone Trapping Network Interactive Map and Data

Black Cutworm Degree Day Accumulations and Life Stages

*Intense Catch is over 15 moths in a week.

True Armyworm Degree Day Accumulations and Life Stages

*Intense Catch is over 15 moths in a week.

Alfalfa Weevil (Hypera postica)

Alfalfa weevil adults are present in fields and are laying eggs. Only the Hudson Valley and Long Island have 1^st to 2^nd instars at 50% occurrence of the life stage. This does not mean that fields in your area might have a small number of larvae that have hatched. They are not at the peak of that life stage yet. When scouting look for the hole in the leaves. The larvae feed on the buds before they unroll into leaflets. When they unroll it reveals the small holes in the leaflet.

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

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

Alfalfa Weevil Shot Hole Damage

Alfalfa Weevil Degree Day Accumulations from March 1 to May 15

Alfalfa Weevil Life stage Development

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

*48 degree F base temperature