September 28, 2017

NYS IPM Weekly Field Crops Pest Report: September 28, 2017

Volume 16 Number 21

Mechanical Cultivation Equipment Demo Day Registration

Tuesday, October 3 at 1 PM – 4:45 PM

371 Big Island Road Goshen, NY 10924

View from the Field

The growing season is coming to a close and we have reached the end of our 16th season of the NYS IPM Weekly Field Crops Pest Report. We would like to thank all the producers, extension educators and field consultants for providing us with in-field observations each week for the report. Your data is critical to us for providing information statewide each week on the status of pests in the field.  We will be posting an end of the season survey to determine what impact the report has had statewide. This survey helps us fine tune the report each year. Please make any suggestions on how we might be able to improve the report.

Again, thank you for all your help and for sharing field observations this season!


I will be posting some off-season articles on the pest report blog about planning your IPM program for the next season.


There are reports of western bean cutworm damage in field corn in Northern NY. Many of the hybrids with the CryF1 BT trait are showing damage. This BT gene is not resistant to western bean cutworm.  The vip3Aa20 gene does have resistance to western bean cutworm. Any conventional hybrid does not have resistance to western bean cutworm.


Weather Outlook – September 28, 2017

Jessica Spaccio

NOAA Northeast Regional Climate Center, Cornell University

Last week temperatures ranged from 10 to 16 degrees above normal! Precipitation has been none at all for most of the state, some areas have seen a few hundredths of an inch. Base 50 growing degree-days ranged from 90-170.

Returning to seasonable temperatures before warming up again next week. First frost possible for some areas Saturday night.

Today temperatures will be in the 60’s for most areas, though southeast NY will reach into the 70’s, with sunny conditions. This will be 20 degrees cooler than earlier in the week for some places! Overnight lows will be in the 40’s.

Friday temperatures will range from the mid 50’s to the mid 60’s with scattered showers and some thunderstorms possible as a cold front passes. Overnight temperatures will be in the 40’s, dipping into the 30’s in northern areas.

Saturday will in 50’s and low 60’s with scattered showers possible in the morning. Overnight temperatures will be in the 30’s and low 40’s with a first frost possible.

Sunday will be sunny with highs in the 60’s. Overnight temperatures will be in the upper 30’s to mid 40’s.

Monday’s highs will warm into the mid 60’s to low 70’s. Lows will be in the 40’s.

Tuesday will be in the 70’s and near 80.  Lows will be in the 50’s.

Wednesday, temperatures will be in the 70’s and near 80.  Lows will be in the 50’s.

The seven-day precipitation amounts will range from a trace to near half an inch.

The 8-14 day outlook (Oct 4-10) favors above-normal temperatures for the state. The precipitation outlook slightly favors below-normal precipitation for a majority of the state.

Maps of 8-14 day outlooks:

National Weather Service watch/warnings map:

US Drought Monitor

CLIMOD2 (NRCC data interface):

Making Fall Alfalfa Field Decisions

Ken Wise, NYS IPM

Sometimes we forget that there are IPM practices for the fall in alfalfa. Conducting stand counts is one of these activities. Fall stand counts are an indication of the health of your alfalfa crop. There are a number of pests and crop management issues that can reduce a stand count in alfalfa. The following are guidelines for stand counts in NYS:

Crowns per square foot
Harvest Year Optimum Stand Adequate Stand
New Spring Seeding 25-40 12-20
1st hay year 12-20 6-10
2nd hay year 8-12 4-6
3rd and older 4-8 2-5

Note: Number of crowns not stems

The following are photos of alfalfa stand counts from the Cornell Research Farm in Valatie, NY

4 year old field-7 crowns/25 stems per square feet

4 plus years in production-5 crowns/15 stems per square feet

4 year old field-15 crowns/45 stems per square feet

New alfalfa seeding- 20 crowns/70stems per square feet

Note that you may have the recommended crowns per square foot but they may not actually be healthy. Make sure to dig a few plants up to check the roots for signs of disease.  You may also want to look at the number of stems per square foot. Here is a guideline for an adequate stand of alfalfa using stem counts.

Stems/square feet Action

Predicted Yield Potential

(assuming on winterkill)

>55 Stem density not limiting yield Same as current year
40 to 54 Some yield reduction expected If in good health same as current year. If not could be significantly less.
<39 Consider replacing stand If in good health same as current year. If not could be significantly less.

Source: University of Wisconsin:


Fall scouting before the first hard frost can also reveal pest problems. Finding yellow to brown plants may be an indication of a disease problem such as: verticillum wilt, leaf spots, fusarium wilt, anthracnose and more. An inspection of the root system can also help diagnose disease problems. Yellow, reddish-brown to black discolored or damaged roots may indicate disease problems such as phytopthora root rot or verticillium wilt. In northern NY counties where alfalfa snout beetles (ASB) have been a problem, premature senescence, stunted or yellow alfalfa fields may indicate an ASB infestation. Fields should be evaluated for presence of the root feeding larval stage.

Pest Records help with the future!

Ken Wise, NYS IPM

Did you have insect pests, diseases, weeds or other pest problems with corn, small grains, soybeans, alfalfa or other forages this summer? Do you want to avoid such problems in the future? Field pest RECORDS is one of the practices we need to do to prepare or avoid many pests that cause reduced yields or quality of our crop. By keeping records on our crops we can better plan for the next year. So if you had a problem with a pest this year before you forget write it down. In recent years we have had a lot of corn in New York infected with grey leaf spot and northern corn leaf blight. There are hybrids that have resistance and yield much better than ones that are more susceptible. If you know the hybrid you planted that was susceptible you can avoid it in the future and select one that has a higher resistance. You could also decide to rotate because you had observed the diseases in the same field for several seasons. By keeping records on potato leafhopper (PLH) on alfalfa you may have observed that they reached threshold 2 times over the course of 4 years.  This will reduce yield and the quality of the forage.  By selecting a PLH resistant cultivar of you can avoid this in the future. By keeping track of rotation you can avoid some risk to diseases like fusarium head blight in small grains like malting barley. By not planting into a former corn field you may reduce the risk of getting the disease because it can over winter on the crop residue.  Were there new weeds or weed escapes you did not expect this year? If you had weed escapes you might reconsider your selection of weed control products. Are your pesticide use records up to date? Rates, dates, efficacy, rotational restrictions, etc. It is always important to keep pesticide records up to date. Did you have western bean cutworm damage this year at lower levels? It would be good to keep track of this pest since it is new to NY and can become a problem in the future. Did your soybeans have white mold this year? Keep track of this because the disease can survive up to 7 years in the soil. You want to make sure not to plant soybean back in that field for several years. Don’t wait too long….there are too many pests and other factors that may keep you from remembering. WRITE IT DOWN


NYS Growing Degree Days


Clipboard Checklist

Keith Waldron, NYS IPM


*Walk fields to check general field condition, weed, vertebrate and other issues

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

*Update crop records and field history


*Monitor potato leafhopper, foliar, systemic and crown rot diseases, signs of alfalfa snout beetle (in counties where ASB has been confirmed).
*Monitor new seedings for potato leafhopper, pythium blight, phytopthora root rot.
*Evaluate established legume stands for health, productivity and potential rotation. Days until harvest

Small Grains:
*Plant winter small grains after the Hessian Fly Free Date.

*Monitor small grain seedings for stand counts, establishment issues


*Monitor late-season corn pests including European corn borer, corn rootworm, western bean cutworm, slugs, foliar diseases such as northern corn leaf blight and gray leaf spot, ear molds, stalk strength/lodging potential, weed issues, nutrient deficiencies, vertebrate damage.


*Monitor for growth stage, soybean aphid, defoliators, foliar diseases, white mold, weed issues, vertebrate damage

*Record diseases present, location and types of weed escapes


*Check water sources, mend fences as needed.
*Check crop growth, clip pastures between grazing as needed
*Monitor for invasive species, plants harmful to livestock
*Review/Plan rotations


*Check stored grain bins for temperature, moisture and signs of mold and insects. Aerate, core, transfer grain or treat as necessary

*Clean and disinfect empty storage bins in preparation for grain harvest
*Mow around storage bins and facility to minimize pest hiding places

 Dairy Cattle Barn Fly Management:

*Expect an increase in fly numbers in barns as flies seek warmer habitats to escape cooler outside temperatures.

*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

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

*Plan to remove insecticide ear tags in fall to reduce risk of developing insecticide resistance