June 22, 2020

NYS IPM Weekly Field Crops Pest Report

View from the Field

Potato Leafhopper

Several Cornell Cooperative Extension Field Crop Specialists report potato leafhopper being over threshold in alfalfa. Potato leafhopper really thrives in hot, dry weather and populations can explode quickly. It is important to get out and check fields NOW! If you have a field over threshold, and is within a week to 10 days of harvest, the best thing to do is cut it and monitor the regrowth. Spraying after damage has occurred will not fix the yield or the quality of the specific cutting.   For more information, please view the following video: IPM for Potato Leafhopper on Alfalfa-Video

Potato leafhopper v-shaped yellowing damage

Potato leafhopper v-shaped yellowing damage

Alfalfa Weevil

There are a few reports of alfalfa weevil over threshold in alfalfa regrowth. With the number of degree-days we have accumulated over the last week or so, the alfalfa weevil should be pupating soon and no longer feeding on the crop.

Alfalfa Weevil Damage

Alfalfa Weevil Damage

True Armyworm

Armyworm has been an issue in a few fields of corn and small grains. Kitty O’Neil (CCE Northern NY) reports a field over threshold for armyworm in corn. Lower levels of true armyworm have been found in small grains in western NY.

If you are over threshold for true armyworm and the larvae are still small, you might consider an insecticide application. A list of products that can be used for armyworm on corn, wheat, oats, barley, triticale, alfalfa, alfalfa/grass mix, grass, pasture and soybeans is provided below.

this is a photo of true armyworm

True Armyworm

Black Cutworm

Aaron Gabriel (CCE Capital District) reports finding high levels of black cutworm in field corn. For more information on black cutworm please view the following video: Integrated Pest Management for Black Cutworm on Field Corn

photo of Black Cutworm Damage

Black Cutworm Damage

Small Grain Diseases

Gary Bergstrom (Cornell University), Janice Degni (CCE South Central NY Team), Jaime Cummings (NYS IPM), Mike Stanyard (CCE Northeast Dairy, Livestock and Field Crops Team) and Christian Malsatzki (CCE Ulster County) report low levels of several diseases in small grains.

 

Map of confirmed strip rust in the USA

Wheat stripe rust has now been confirmed in four counties in New York, as reported by Gary Bergstrom.

Cereal Leaf Beetle

Gary Bergstrom (Cornell University), Janice Degni (CCE South Central NY Team), Jaime Cummings (NYS IPM), Mike Stanyard (CCE Northeast Dairy, Livestock and Field Crops Team) and Christian Malsatzki (CCE Ulster County) reports cereal leaf beetle in small grains. The infestations range from low to high.

Black Cutworm and True Armyworm flights from April to June

This is a graph show the weekly moths caught in pheromone traps weekly across New York State

Weekly moths caught in pheromone traps weekly across New York State

 

Alfalfa Weevil and Base 50 F Degree Days

June 19, 2020

table of degree days for alfalfa weevil and base 50 degrees

Stage  

Alfalfa Degree Days Life Stages

(Base Temperature 48F)

Egg Hatch                   280

Instar 1                        315

Instar 2                        395

Instar 3                        470

Instar 4                        550

Cocooning                  600

Pupa                            725

Adult Emergence        815

  

Black Cutworm and True Armyworm Degree Days

June 19, 2020

 

table of black cutworm and true armyworm degree days in New York State

Black Cutworm Degree Days (Base 500 F) Lifecycle Growth Stages

Degree Days               Stage                           Feeding Activity

0                                  Moth Capture              Egg Laying

90                                Eggs Hatch

91-311                         1st to 3rd Instar           Leaf Feeding

312-364                       4th Instar                     Cutting Begins

365-430                       5th Instar                     Cutting Begins

431-640                       6th Instar                     Cutting Slows

641-989                       Pupa                            No feeding

Source: University of Minnesota Insect Pest of Corn-Stand Reducers Black Cutworm

 True Armyworm Degree Days (Base 500 F) Lifecycle Growth Stages

Degree Days               Stage                           Feeding Activity

0                                  Moth Capture              Egg Laying

113                              Eggs Hatch

612                              Larval stages               Leaf Feeding

909                              Pupa                            No feeding

Source: Scouting for True Armyworms Is Highly Recommended in Small Grains and Early Corn-University of Kentucky

True armyworm insecticides registered in NYS for field crops

 

Armyworm Field Crop Insecticides for NYS

 

Clipboard Checklist

Keith Waldron, NYS IPM

 

 General

*Walk fields to check general field condition, weed issues

*Watch for crop maturity, stand assessments, weed escapes, lodging issues

 

 Alfalfa:

*Evaluate established legume stands for approximate days until harvest
*Monitor potato leafhopper
*Monitor new seedings for potato leafhopper, pythium blight, phytopthora root rot.

Small Grains:
*Monitor winter grain fields for growth stage, disease issues, cereal leaf beetle
*Check stands for diseases, cereal leaf beetle, weed escapes

*Monitor winter wheat and winter malting barley for signs of Fusarium Head Blight

*Monitor spring grains for potential risk of fungal diseases – consult Fusarium Head Blight prediction model

 

Corn:
*
Conduct plant population assessments, early season corn pests including seed corn maggot, white grub, wireworm, black cutworm, armyworm, slugs, diseases, weed issues, vertebrate damage

 

Soybeans:
*
Post emergence weed evaluation, timely cultivation and/or weed management
*Conduct plant population assessments, early season corn pests including seed corn maggot, slugs, soybean aphid, diseases, weed issues, vertebrate damage

 

Pastures:
*
Check and mend fences as needed.
*Check crop growth
*Invasive species, plants harmful to livestock
*Review/Plan rotation system

 

Equipment:
*Remove / clean soil and crop debris from equipment
*
Arrange for custom weed control or check your own application or cultivator equipment for repairs.
*Carry appropriate / necessary NYS DEC and EPA required documents: (pesticide applicators license, pesticide labels, MSDS sheets, etc.) with application equipment
*Calibrate:

  • planting equipment – maintain records on planting rate per field
  • manure spreaders – maintain records on amount spread per field
  • pesticide application equipment – Check nozzles, pumps, etc., recalibrate pesticide application equipment before use. Maintain pesticide use records

 

Storage:
* Check stored grain bins for temperature, moisture and signs of mold and insects. Aerate, core, transfer grain or treat as necessary
*
Check forage allocation and anticipate feed program adjustments as forages from previous year are used up
*Plan where forages should be stored for optimum allocation next feeding season
*Mow around storage bins and facility to minimize pest hiding places

 

Dairy Cattle Barn Fly Management:
*Monitor animals and barn area for house fly, stable fly and other pest management needs including presence of rodents and birds.
*Check facilities for favorable fly breeding conditions: (organic matter + moisture): leaks in watering systems, roof gutters for leaks and potential overspill, drainage,
*Sanitation, sanitation, sanitation – clean animal resting areas, feed troughs, minimize source of moist organic matter i.e. fly breeding areas in barn and in adjacent animal loafing yard
* Continue fly monitoring: install “3X5″ index card fly speck monitoring cards throughout barn
*Use, replenish, replace fly management materials: sticky fly tapes/ribbons, insecticide baits, natural enemies (parasitoids), fly population monitoring (3 x 5) spot cards
*Consider purchase and release of Muscidifurax raptor and/or M. raptorellus natural enemies of house and stable fly pupae.

 

Dairy Cattle on Pasture:
*Monitor animals for presence of face flies, horn flies and stable flies. Action guidelines: face flies (average 10 per animal face), horn flies (average 50 / dairy per animal side, 200 / beef cattle per animal side), stable flies average 10 per animal  (all four legs)
*Check feed bunk / water source locations for signs of stable fly breeding (moist undisturbed organic matter – spilled feed, round bales, etc.), minimize source of moist organic matter i.e. fly breeding areas in barn and in adjacent animal exercise yard.
*Check pasture for forage quality / quantity, rotate as appropriate
*Check pasture for vegetation poisonous to livestock
*Consider use of pasture fly traps to help reduce deer, horse and stable fly populations