May 27, 2016

NYS IPM  Weekly Field Crops Pest Report, May 27, 2016

Volume 15- Number 4

View from the Field

Extension educators around the state report most of the corn has been planted and soybean plantings are going well. They also report winter small grains look very good this year so far. Be aware that thunderstorms are predicted this week and proper timing of wheat fungicide treatments relative to flowering is critical to prevent fusarium head blight (AKA scab). Many farmers are starting to cut grass and alfalfa for hay, haylage or silage. Most of the state is very dry and the coming rains will be welcome.

This week we initiated trapping for black cutworm and true armyworm moths in eastern and central NY. In the years to come we will be continuing to check for these early season migrant pests. So far our traps have caught nothing to very low numbers of these pests.

Aaron Gabriel (CCE Capital District) reports finding cereal leaf beetle damage on oats. There was 1 beetle per every five plants. This is below the economic threshold. The threshold before the boot stage is 3 larvae/stem. At the boot stage it is one per flag leaf.


Cereal Leaf beetle Larvae

Weather Outlook – May 26, 2016

Jessica Spaccio

NOAA Northeast Regional Climate Center, Cornell University

Last week temperatures ranged from 4 degrees below normal to 2 degrees above normal. Precipitation was less than an inch for the state, with most areas seeing less than ¼”.  Base 50 growing degree-days ranged from 20 to 70.

Summer-like weather (warm, humid, afternoon thunderstorms)…

Today mostly sunny and warm with temperatures will in the upper 70’s and 80’s. Isolated afternoon showers and thunderstorms are likely. Overnight lows will be in the upper 50’s and 60’s.

Friday will be mostly sunny and warm again in the 80’s, even 90 possible. Scattered thunderstorms are possible in the afternoon. Lows will be in the upper 50’s and 60’s.

Saturday temperatures will be in the upper 70’s to 80’s, 90 possible, with isolated afternoon showers and thunderstorms. Overnight temperatures will be in the mid to upper 60’s.

Sunday’s highs will be in the mid 70’s to mid 80’s.  Isolated afternoon showers and thunderstorms are possible. Overnight temperatures will be in the mid 50’s to low 60’s.

Monday temperatures will be slightly cooler in the 70’s, some low 80’s, with an increased chance of showers and thunderstorms from a cold front. Lows will be in the mid 50’s to low 60’s.

Tuesday will be in the mid 70’s to low 80’s with a continued chance of showers and thunderstorms.  Lows will be in the upper 50’s to low 60’s.

Wednesday will be in the 70’s and some low 80’s possible. Lows will be in upper 50’s to low 60’s.

The five-day precipitation amounts will range ¼” to over 1 ½”.

The 8-14 day outlook (June2-8) shows equal chances for above or below normal temperatures fro all but the southeast corner of the state that has an increased chance (33-40%) of below normal temperatures. Most of the state has an increased chance (33-40%) of above normal precipitation.

June outlook shows increased chances (40-50%) of above normal temperatures for the entire state. There are equal chances of above or below normal precipitation.

The June/July/August outlook shows increased chances (50-60%) of above normal temperatures for the entire state. There is an increased chance (33-40%)for above normal precipitation in the northeast portion of the state.

The Drought Monitor: Abnormally dry conditions have expanded in the Adirondacks due to short-term precipitation deficits, low streamflows, and dry soils.

Maps of 8-14 day outlooks

National Weather Service watch/warnings map

US Drought Monitor

CLIMOD2 (NRCC data interface)

Barn Flies? – Early Season Efforts Will Pay Off!

Keith Waldron NYS IPM

Barn Flies? Given the right conditions barns and other livestock facilities can offer great habitats to develop house and stable fly populations. The good news is that early intervention can help minimize 90% or so of the potential fly problem. A little management time each week will pay big dividends as the season progresses. The two most common fly species found in barn areas are the house fly and stable fly. Both fly species prefer to lay their eggs in moist, not wet, moist decaying organic matter such as spilled feed, moist hay, wet grain, and straw bedding. These areas are great habitats for maggots to develop leading to populations of these nuisance flies.

Keeping potential fly breeding habitat dry will minimize their attractiveness and suitability for house and stable fly populations find refuge and increase. House and stable flies are cold-blooded meaning their activity is greatly affected by temperature. Cooler temperatures slow down fly population development. For example, when temperatures average 68 F the house fly can grow from egg to adult in 18-21 days. At higher temperatures, say 86 F, development speeds up considerably, taking only 9 – 11 days to go from egg to an adult fly. Take home message? If fly breeding conditions are favorable and it get’s warmer, the fly situation on farms can change quickly and dramatically. Here are a few tips to help avoid fly population surprises and potential problems.

Keep it dry.
Check water sources for leakage, if water buckets are used with animals, such as in calf pens or holding areas, empty water buckets outside. Our weather has been dry lately but after rains, check rain gutters and outside water diversions for effectiveness. Clean feed spills around outside feeding rings and feed troughs. Left undisturbed these areas can be ideal stable and house fly breeding areas

 Sanitation, Sanitation, Sanitation! Staying ahead of fly populations begins with cultural practices that eliminate conditions favorable to fly breeding. House flies and stable flies both breed in areas where moist undisturbed organic matter such as spilled feed and manure-soiled bedding are present. Another favorable breeding spot is a location that remains relatively undisturbed and offers protection from foot and hoof traffic. Frequent clean out of these favorable breeding habitats and other activities that enhance dry conditions in animal areas will make the local environment inhospitable to successful buildup of fly populations. Removing fly breeding habitat frequently, daily if possible, or at least once or twice a week at a minimum. With dry conditions and sound sanitation as the foundation for fly management, additional tactics can be brought to bear.

 Choice of animal bedding material. Studies have shown moist undisturbed straw is a very good medium for production of house and stable flies. Where possible avoid straw for animal bedding during the summer fly season. Substituting sand, gravel, wood chips/shavings, sawdust or other materials for straw bedding has been shown to significantly reduce house and stable fly maggot populations when compared to straw bedding under the same conditions. Also note: The more animal bedding can stay dry, i.e. better drainage and frequent changing, the less hospitable it is for a fly population to develop.

Protect Natural Enemies.
A variety of biological control agents occur naturally in the typical dairy barn. These include various predators of house and stable fly eggs, larvae and adults. When sanitation, is used effectively, natural enemies can more easily keep up with remaining fly populations and can be quite effective at reducing their numbers. The key is to employ sound sanitation, early and as often as practical, as the first line of defense for mitigating fly populations. Common fly predators include predaceous mites, rove and Carcinops beetles, parasitoid wasps, and fly diseases. Fly parasitoids, small wasps that attack fly pupae, are quite effective at reducing fly populations. These tiny wasps do not attack animals or humans. The fly parasitoids can, however, take up to three times longer to develop than the house fly. For this reason their populations can use a “jump start” early in the season to reach the numbers needed to head off house fly problems. Those wishing to use parasitoids to enhance their biological control efforts should begin parasitoid releases early in the season – mid to late May is recommended. There is still time to begin releasing the wasps in barns and calf housing areas. Parasitoids should be released close to their prey, i.e. in and around potential fly breeding habitats. Cornell research has shown the dairy fly parasitoids (Muscidifurax raptor and Musicifurax raptorellus) to be the most effective fly predators for use in dairy facilities in New York. Reducing the number of adult (breeding) flies helps minimize the potential for fly population buildup.

 Sticky Situations. Two additional fly management tactics to curb fly numbers include use of sticky ribbons, tapes, fly string on a reel and insecticide baits. Sticky ribbons (including the wide roll types) and tapes on a reel offer an effective non-toxic means to capture adult flies. Place sticky tapes in areas not at risk from high winds, turbulent air and dusty conditions. Insecticide: sugar bait stations can also be deployed to capture and kill adult flies. Each female house fly can produce up to 600 eggs. Each stable fly female produces up to 400 eggs. Reducing the breeding fly population can pay big dividends!

For more information on IPM for barn fly management see: IPM for Livestock (, Integrated Management of Flies in and around Dairy and Livestock Barns  ( and  Integrated Pest Management Guide for Organic Dairies (


Fusarium head blight and stripe rust commentary

Gary Bergstron, Cornell University Plant Pathologist

May 27, 2016:

Winter wheat in New York is either beginning to flower now or will do so over the next week. The triazole products Caramba and Prosaro are the most effective fungicides for suppression of FHB and DON contamination when applied at flowering (emergence of anthers on heads).  There is an application window of approximately 6 days from the beginning of flowering in which reasonable FHB suppression can be expected.  Fungicide products containing strobilurins should not be applied to headed wheat or barley as they may result in increased levels of DON in grain. Caramba or Prosaro applied at flowering will also provide protection of flag leaves against stripe rust (see photo) – an imminent threat at this time.  Based on the finding of severe stripe rust (photo courtesy of Mark Avery of Carovail) in some fields in northern Cayuga County this week and high levels of stripe rust in much of the north central, southern and eastern U.S. that could provide spores for aerial transport into New York, I am advising New York wheat growers to consider fungicidal protection of flag leaves against stripe rust infection at this time.  The variants of stripe rust being found affect wheat but not barley.


Most winter malting barley fields experienced head emergence and flowering during the past several days and many had Prosaro or Caramba applied at full head emergence.  For fields less than a week after head emergence, a triazole spray may still be warranted. Other disease being observed in winter malting barley include scald, powdery mildew, and seedborne loose smut in certain cultivars.


While the current risk of FHB epidemics is low over most of the state, that risk could increase.  Check the Fusarium Risk Assessment Tool ( and your local weather forecast frequently as your crop approaches heading and flowering.  We hope to see many of you at the Small Grains Management Field Day at Cornell’s Musgrave Farm in Aurora, NY on June 2 (see for details).

Beneficial” Tip of the Week

Ken Wise, NYS IPM

Slugs that damage soybeans in no-tillage practices early in the spring have a vast array of predators which include: ground beetles, rove beetles, centipedes, daddy longlegs, firefly larvae, soldier beetle larvae, birds, and frogs.  In particular ground beetles are a general predator that feed on a wide variety of insects and slugs. Almost all corn and soybean seed are currently being treated with an insecticide and it is systemic. Recent research shows that slugs that have eaten soybean seed treated with the insecticide are not affected. Predators such as ground beetles that feed on the slugs that have ingested the insecticide treated seed can be affected negatively. Research has shown an increase in damage to crops and reduced yields because of higher slug populations.

Source: Penn State University: Insecticides foster ‘toxic’ slugs, reduce crop yields 

Weed of the Week-Purple Deadnettle (Lamium purpureum)

Ken Wise, NYS IPM

While scouting alfalfa/grass mixed forage fields this week I saw a fair amount of purple deadnettle. This winter annual can be found in lawns, turf or forage fields. Purple deadnettle has distinct purple leaves and flowers. The plant germinates in the fall and flowers in the spring.


Purple Deadnettle2

Proper fertilization and a 3 to 4 year crop rotation can help prevent this weed from becoming a problem. There are herbicide options for controlling broadleaf weeds. (See the Cornell Guide for Integrated Field Crop Management for chemical recommendations.

Degree Day Models for Field Crops across New York

Ken Wise, NYS IPM

Alfalfa Weevil Degree Days

Growing degree Days for peak (50%) Occurrence of Alfalfa Weevil growth stage:


Degree Days

(Base 48)

Egg 280
Instar 1 351
Instar 2 395
Instar3 470
Instar 4 550
Cocooning 600
Pupa 725
Adult Emergence 815

 (Note: for alfalfa weevil predictions use Base Temp of 48F)

 Seed Corn Maggot Peak Flight and Fly Maggot Free Degree Days

Base Temp = 390 F Peak 1st Generation Seed Corn Maggot Fly Free degree days Peak 2nd Generation Seed Corn Maggot fly Free degree days Peak 3rd Generation Seed Corn Maggot fly Free degree days
degree days 360 810 1,080 1530 1800 2250

Source: Insect IPM for Organic Field Crops: Seed Corn Maggot by Katelin Holm and Eileen Cullen

Black Cutworm Degree Day Model

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 Black Cutworm Trapping Network

2016 New York Field Crop Pest Degree Day Accumulations for selected locations

Station Location

Alfalfa Weevil

(Base 48 F)

March 1


(Base 50 F)

March 1

Black Cutworm

(Base 50 F)

April 20

Seed Corn Maggot

(Base 39 F)

January 1

Ceres 210 141 104 726
Chazy 214 168 158 580
Geneva 261 197 157 754
Highland 405 311 219 1062
Ithaca 182 127 95 663
Long Island (Northport) 392 284 201 1087
Massena 197 155 149 540
Ripley 275 203 135 842
Valatie 295 223 164 870
Versailles 291 202 147 779
Watertown 164 116 107 575
Wayland 227 165 122 654

NEWA Growing Degree Days


Alfalfa Weevil Degree Days (Base 48 degrees)


Growing Degree Days (Base 50 degrees)

Clipboard Checklist

Keith Waldron, NYS IPM


*Pre- and post-plant weed evaluation, timing cultivation and/or post-emergent weed management
*Watch for early season weeds: winter annuals, chickweed, henbit, field penny cress, shepherd’s purse, giant and common ragweed, purple deadnettle, lambsquarters, redroot pigweed, velvet leaf, Pennsylvania smartweed, common sunflower, quackgrass, foxtail

*Evaluate established legume stands for harvest.
*Monitor for alfalfa weevil, crown or foliar diseases
*Monitor new seedings for Pythium blight and Phytopthora Root Rot.
*Monitor for Alfalfa Snout Beetle (In Oswego, Jefferson, Cayuga, Wayne, Lewis, St. Lawrence, Clinton, Essex, and Franklin counties)

Small Grains:
*Monitor winter grain fields for growth stage, disease presence or risk, weed issues (such as winter annuals, corn chamomile and chickweed), growth stage, number of tillers

* Evaluate stands for risk of fungal diseases (See above Dr. Bergstrom’s article above)
*Check stands for soilborne virus diseases, Wheat spindle streak mosaic and Soilborne wheat mosaic, check for signs of powdery mildew or other maladies, cereal leaf beetle, weed escapes, goose damage

*Plant corn as conditions allow
*Pre- and post-plant weed evaluation, timing cultivation and/or pre- and post-plant weed management

*Emergence: assess stand, population count, bird and early season insect issues e.g. black cutworm, wireworm, white grubs.

*Plant soybeans as conditions allow
*Pre- and post-plant weed evaluation, timing cultivation and/or post emergence weed management

*Emergence: assess stand, population count

Check and mend fences as needed.
*Check crop growth
*Monitor fields for invasive species, plants harmful to livestock
*Review/Plan rotation system

*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

-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.

* 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