NYS IPM Weekly Field Crops Pest Report, July 1, 2019

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Volume 18 -Number 9

 Cornell University Willsboro Research Farm Open House

Willsboro, NY – June 12, 2019

The Cornell University Willsboro Research Farm will hold an open house on Wednesday, July 10 from 1:30pm to 4:00pm.  A tour of the facilities and research plots will leave the main office (48 Sayward Lane, Willsboro) at 2:00pm.  Light refreshments will be provided.

Research topics featured at this year’s open house include industrial hemp trials, insect exclusion netting for cucumbers, corn silage variety evaluations, soil health plots, cover crops, warm-season forage options, juneberry nursery and production trials, Aronia variety plantings, honeyberry variety trial, reduced tillage demonstration plots, and grain plots of winter triticale, winter rye, and winter barley.

In 1982 E. Vreeland Baker, a Willsboro farmer and entrepreneur donated his 352-acre farm to Cornell University for agricultural research and demonstration.  The facility serves to connect Cornell faculty in Ithaca with the challenges and issues facing North Country farmers.  Willsboro Research Farm is part of the Cornell University Agricultural Experiment Station.

This event is free and open to the public.  For more information call 518-963-7492.

View from the Field

Black Cutworm

Black Cutworm is still causing problems in corn. The threshold is 5% of the plants show damage.

black cutworm

black cutworm (Photo by Jaime Cummings)

True Armyworm

There are reports of true armyworm in corn. Armyworms feed on the leaf margin and work their way to the midrib of a leaf. Pellet-like frass on the plant are indications of armyworm infestations. Armyworms generally feed at night on leaves of corn, grasses and small grains. When infestations are at extreme levels, they will feed and march from field to field during the day.


Economic Thresholds

  • Corn – More than 50% of plants show armyworm feeding, live larvae less than 1 – 1/4 inches long are numerous in the field
  • Wheat – 5 or more larvae per linear foot of row, larvae less than 1.25 inches and not parasitized, watch for flag leaf reduction or if grain heads clipped off – yield losses, a spray before soft dough to save the remaining 3 upper leaves is generally beneficial since these tissues are still important to grain filling
  • Grasses – no specific guidelines available need for treatment based on the level of damage observed in relation to the expected value of grass harvest


There are many reports of slug damage in corn. It will likely start in soybeans as they emerge.

Snail/Slug Damage

Potato Leafhopper

Across the state, there are many reports of potato leafhopper (PLH)  approaching threshold in alfalfa. The nymphs are starting to appear and will cause a lot of damage to alfalfa unless you get out and check your fields. Once you see the V-shaped yellowing in the field it is too late. The quality and yield diminish. You lose 5% protein and a least ½ ton per acre of alfalfa. Catch it before that happens by scouting fields now.

Potato Leafhopper Adult

Potato Leafhopper Adult

Potato Leafhopper Nymphs

Potato Leafhopper Damage to Alfalfa


Here is the link to a video on how to scout for PLH: https://www.youtube.com/watch?v=8BIZYTq7Zec&t=1s

Here is an article short article on how to scout for PLH in alfalfa: Time to Scout for Potato Leafhopper in Alfalfa

Here is a Cornell factsheet on PLH management in alfalfa:  https://ecommons.cornell.edu/bitstream/handle/1813/42384/plh_shields_1990.pdf?sequence=1

Stable Flies on Cattle

We have a dairy fly IPM demonstration at Shunpike Dairy in Dutchess County. There were many stable flies on the cattle this last week. The good thing is that you can limit the habitat and can reduce them on the farm. Cleaning up moist rotting organic matter where they lay eggs reduces the number on the farm. If these areas are cleaned weekly it will limit the number of stable flies on the farm. Places like the manure handling areas, feeding and feed handling areas, where hay is left on the ground, corners that may not be cleaned out in the barn, straw or grass as bedding and any moist organic matter. A handful of moist rotting organic matter can produce 100’s of flies.

Feed Handling Area (house and stable fly habitat)

Manure Handling Area (house and stable fly habitat)

Grass Hay on the Ground (house and stable fly habitat)


Stable Flies focus on the legs of the cattle

Weather Outlook – June 27, 2019

Jessica Spaccio

NOAA Northeast Regional Climate Center, Cornell University

Last week temperatures ranged within 2 degrees of normal. Precipitation has ranged from a quarter of an inch to over 3 inches. Base 50 growing degree-days ranged from 70 to 150.

Mostly dry day today, possible severe storms on Friday and Saturday.

Today will be a mostly dry day with temperatures in the low to mid-80s and continued humid conditions. Overnight lows will be in the upper 50s to mid-60s.

Friday temperatures will be in the low to mid-80s with showers and thunderstorms possible in the afternoon to evening. Some storms could become severe (main concerns are damaging winds, large hail, and torrential downpours). Overnight temperatures will be in the 60s.

Saturday temperatures will be in the upper 70s to low 80s. There will be some lingering morning showers, then clearing with scattered afternoon showers and thunderstorms possible. Potential exists for strong to severe storms. Overnight temperatures will be in the 60s.

Sunday highs will be in the upper 70s to low 80s with scattered showers and thunderstorms possible before clearing and lower humidity. Overnight temperatures will be in the mid-50s to near 60.

Monday will be mostly dry, some isolated storms are possible, with temperatures in the 70s. Overnight temperatures will be in the mid-50s to low 60s.

Tuesday highs will be in the 80s with scattered showers and thunderstorms possible. Overnight temperatures will be in the 60.

Wednesday highs will be in the upper 70s to low 80s. Overnight temperatures will be in the 60s.

The seven-day precipitation amounts will range from a trace to ¾ “.


The 8-14 day outlook (July 4-10) favors above-normal temperatures for all of the state and slightly favors above-normal precipitation for part of the state.


Maps of 8-14 day outlooks

National Weather Service watch/warnings map

US Drought Monitor

CLIMOD2 (NRCC data interface)

Storing grain? Not too early to think about protection from post-harvest insect pests

Keith Waldron, NYS IPM

Planning to store wheat on the farm? Are your grain bins ready? Wheat harvest is still a while off but it is not too early to begin thinking about gearing up for the big event. To maintain the profits a good yield can bring, make and follow a plan to protect your grain while it is in storage. Remember: Grain storage will not improve grain quality. However, proper management of grain during storage will protect the quality present at harvest.

The IPM approach for stored grain protection includes a combination of sanitation, well-sealed bins, frequent monitoring for temperature and insect populations, aeration to cool grain in the fall, and pest management treatments as needed. Stored grain management begins with “an ounce of prevention”. This article will highlight some steps one can take now to protect stored grain before it is harvested. The following pre-harvest information was “gleaned” whole or in part from Stored Grain IPM information from Oklahoma State University Stored Products Research & Education Center and Purdue University. Website source URL’s are provided at the end of this article.

Insect infestations are the more common stored grain pest issues one might encounter. Insect infested grain can be docked at the time of sale. Most common grain bin insect problems can be traced back to infestations in previously stored material, cracked grain and grain fines and trash. Don’t add new grain into storage bins that have not been cleaned and may harbor a collection of stored grain pests. The key to prevention is SANITATION – clean out the bin every time it is emptied. How clean? If you can tell what was stored in the bin the last time it was used, it needs more cleaning. In addition to insects, birds and rodents are also attracted to left over and spilled grain. Lights mounted on or in close proximity to grain bins may attract unwanted stored grain insects.

Who might the likely insect pests be? A variety of beetles, weevils and moths are common to stored grain infestations. Saw-toothed grain beetles, flat grain beetle, red flour beetles, granary weevils, Indian meal moths and Angoumois grain moths to name a few. A picture is worth a thousand words and the following extension factsheets provide information to help identify the insects you may find as you clean out your storage bins: Principal Stored Grain Insect Pests of Indiana, Stored Wheat Insects identification key (http://bru.gmprc.ksu.edu/proj/sga/key.asp) and Stored grain pests identification (http://storedgrain.com.au/wp-content/uploads/2013/05/Stored-grain-pests_NorthSouthWest_Pocketguide.pdf).

To prepare for grain harvest and storage the following sanitation practices are recommended.

* Clean harvest and transportation machines before harvest.

* Repair all grain handling equipment before harvest and keep it in good condition.

* Seal unloading auger, auger tube opening, and side door openings before harvest

* Empty storage structures of old grain. The new crop should never be stored on top of old grain.

* Remove and destroy any grain from beneath, around or near the bin area. Sweep and vacuum the floors, false floors, and walls inside empty bins to remove old grain and debris. This debris usually contains insect eggs, larvae, pupae, and/or adults, all ready to infest the new grain. A shop vacuum, broom and scoop are very useful in a cleanup job, and all collected material should be discarded properly.

* Check fan boxes for possible grain pests.

* Remove any spilled grain outside the storage structure.

* Mow / remove weeds at least 10 feet around the bins.

* Check and clean or replace rodent traps / bait stations. Be sure to follow all label directions.

* Check the integrity of screens and porcupine wires to limit bird entry and roosting.

* Insecticides? For additional protection against infestation, the inside and outside surfaces, foundations and floor of a storage facility can be sprayed with residual insecticide, four to six weeks prior to harvest, to kill any insects that were not removed during cleaning and those that migrate into the bin. Use appropriately registered insecticides. Be sure to follow all label directions. Rotate choice of insecticide chemical families to minimize risk of developing insecticide resistance.

* Establish a written sanitation schedule. Keep appropriate records.


Bin Sealing

Roof leaks commonly lead to columns of spoiled grain. Check for these leaks by looking for light coming into the bin. Moisture coming into the bin through the seal between the bin and concrete will cause spoilage around the perimeter of the bin at the base. Check the seal since sealants do deteriorate. Water will run away from the seal at the base of the bin wall if the concrete is sloped away from the bin. Also check the seals around the doors and hatches.

Besides keeping grain dry, grain storages should be well sealed for two other basic reasons: (1) to minimize grain insect entry problems into base and sidewall grain, and
(2) to minimize leakage should fumigants be used.

In addition, improved insect kill (efficacy), tighter sealed structures require lower dosage rates, which reduce the cost of future fumigations and cover the cost for the sealing materials and labor. When clean grain is transferred into a clean, sanitized structure with base and sidewalls well sealed, the main insect infestation and population growth should be on the grain surface in the structure headspace. Permanently sealing all non-functional base, sidewall and roof openings is the first priority of sealing storages. The second sealing priority is to seal functional openings at all times during the year when the component is not being used.

Source of the above stored grain pest management information:
Purdue’s Stored Product Pest factsheets:


Two excellent Stored Grain IPM resources:

“Stored Product Protection” – Practical guide to protecting grains and other raw commodities, food processing facilities, finished food, and durable plant and animal products from insects, molds, and vertebrate pests. Illustrated, 350 p. (http://www.ksre.ksu.edu/bookstore/pubs/S156.pdf)


Maintaining Quality in On-Farm Stored Grainhttps://utextension.tennessee.edu/publications/documents/PB1724.pdf


Clipboard Checklist

Keith Waldron, NYS IPM


*Walk fields to check general field condition, weed issues

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


*Evaluate established legume stands for approximate days until harvest
*Monitor potato leafhopper, foliar, systemic and crown rot diseases.
*Monitor new seedings for potato leafhopper, pythium blight, phytopthora root rot.
Small Grains:
*Monitor small grains for signs of Fusarium Head Blight, foliar diseases

*Monitor grain fields for growth stage, disease issues, grain maturity, harvest timing
*Record diseases present, location and types of weed escapes

Monitor for mid-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, weed issues, nutrient deficiencies, vertebrate damage.

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

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

*Carry appropriate/necessary NYS DEC and EPA documents as needed: (pesticide applicators license, pesticide labels, MSDS sheets, etc.)

* 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
Check forage allocation and anticipate feed program adjustments as forages from previous year are used up
*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 the 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 the 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 the source of moist organic matter i.e. fly breeding areas in the barn and in the 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


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