Black cutworm (Agrotis ipsilon)

Black cutworm moth captures have been very high in western and eastern NY this year. Larvae will likely be feeding soon. Watch for leaf feeding with the early larval instars. Once the larvae reach the 4^th instar they will start cutting plants off. The threshold for black cutworm is 5% of the plants have been cut. Make sure to scout and have an educated decision behind the use of an insecticide.

Information on Black Cutworm

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

 

True Armyworm (Mythimna unipuncta)

There have only been a few intense catches of true armyworm (see in the table below). While we have low populations this year there can be isolated cases that a field may get a higher population. It is best to scout every 7 to 10 days for all early season insect pests of corn.

Information on True Armyworm

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

NYS Field Crops Pheromone Trap Data Report  Interactive Map

Black Cutworm Degree Day Accumulations

*Location for Intense Catches	Black Cutworm Degree Days (Base 50)	Life Stage
Seneca Falls Seneca County April 20	153	1st-3rd Instar Leaf Feeding
Amenia Dutchess County April 28	209	1st-3rd Instar Leaf Feeding
Seneca Falls Seneca County April 26	132	1st-3rd Instar Leaf Feeding
Amenia Dutchess County May 3	210	1st-3rd Instar Leaf Feeding
Seneca Falls Seneca County May 3	132	1st-3rd Instar Leaf Feeding
Linwood NY Livingston County May 4	142	1st-3rd Instar Leaf Feeding
Amenia Dutchess County May 10	174	1st-3rd Instar Leaf Feeding
Charleston Montgomery County May 23	37	Egg Laying

*Intense Catch is over 15 moths in a week.

True Armyworm Degree Day Accumulations

*Location for Intense Catches	True Armyworm Degree Days (Base 50)	Life Stage
Phelps Ontario County April 20	153	Leaf Feeding
Phelps Ontario County April 30	132	Leaf Feeding

*Intense Catch is over 15 moths in a week.

 

 

 

Alfalfa Weevil (Hypera postica)

Alfalfa weevil may be an issue in alfalfa regrowth this year. It is important to keep scouting for alfalfa weevil over the next few weeks. Alfalfa weevil is normally controlled with the 1^st cutting of alfalfa. Since it has been colder this year the weevil has been delayed and most areas are just starting to see damage. When scouting look for the holes 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. First instar larvae are very small and can be found in the buds of the alfalfa.

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 Degree Day Accumulations from March 1 to May 28

Weather Station Location	Alfalfa Weevil Degree Days	Life Stage
Arkport	316	Leaf Feeding-1st instar
Bergan	323	Leaf Feeding-1st instar
Canton	297	Egg Laying
Ceres	293	Egg Laying
Conesus Lake	350	Leaf Feeding-1st instar
Corwin	299	Egg Laying
Geneva	325	Leaf Feeding-1st instar
Highland	515	Leaf Feeding-3rd  instar
Ithaca	351	Leaf Feeding-1st instar
Kinderhook	438	Leaf Feeding-2nd  instar
Lafayette	361	Leaf Feeding-1st instar
Laurens	293	Egg Laying
Northport	572	Leaf Feeding-4th  Instar
Peru	320	Leaf Feeding-1st instar
Red Hook	448	Leaf Feeding-2nd  instar
Versailles	353	Egg Laying
Watertown	260	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 (Oulema melanopus)

Cereal leaf beetles were out in force in western NY this week. Some wheat fields were sprayed this week for cereal leaf beetle. Make sure to use scouting and thresholds for making decisions for insecticide applications. Use the following lifecyle map to help make identification decisions and timing of scouting.

For more information on Cereal Leaf Beetle:

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