July 31, 2015: Volume 14 Number 13
View from the Field
Paul Cerosaletti (CCE Delaware County) reports true armyworm injury in several corn fields in the north-east end of the county. The larvae were ½ inch to an inch long.
Photos taken by Heather Magnan
True armyworm larvae appear smooth cylindrical pale green too brownish when they are still small. Mature larvae are smooth and marked with two orange, white-bordered strips on each side. True armyworm ranges in size from 1/8 inch to 1.5 inches long.
Photos taken by Heather Magnan
It is important to detect armyworm areas early, while larvae are still small, since large larvae do most of the feeding and quickly destroy whole stands of corn, grasses and small grains. Because armyworm feeds at night look for chewed leaves, cut stems, lodged plants, pellet-like frass on the ground, and larvae hidden under plant canopy and surface residue. You will need to be aware that armyworms can move from field to field every quickly. Monitor fields for armyworm larvae when they are less than 1/2 inch long. If there are sufficient numbers and damage is present, an insecticide could be justified. Treat only the affected area and a 20 to 40-foot border around the infestation. Rarely does a whole field need to be treated for armyworm. Larger armyworm larvae, greater than 1/2 inch long, are much more difficult to control. These large larvae are more tolerant of insecticides, reducing the effectiveness and economic viability of this option.
There are various reports on soybean aphid populations in New York. Keith Severson (CCE Cayuga County) reports that several fields are over threshold and need to be sprayed. Mike Stanyard (CCE Northeastern Dairy and Field Crop Team) reports that fields he has scouted are below threshold with the exception of areas near Lake Ontario. Ken Wise (NYS IPM) 5 fields are below threshold in the Mid-Hudson Valley but are starting to increase in population.
There are a lot of reports of winter small grains having fusarium head blight. In some cases more than 50% of the plants showed symptoms. Justin O’Dea (CCE Ulster County) reports that there is a lot of bird damage in small grains in Ulster County.
Weather Outlook – July 30, 2015
NOAA Northeast Regional Climate Center, Cornell University
Last week temperatures ranged from normal to 2 degrees below normal across much of New York. Portions of the Hudson Valley, and far northern and western NY saw zero to 2 degrees above average with portions of west central NY 2 to 4 degrees below average. Precipitation ranged from zero across western and portions of central NY to one inch across portions of the Catskills, Finger Lakes, and Adirondacks. Base 50 growing degree-days ranged from 70 to 170. 
Slightly cooler week ahead . . .
Today will feature a line of showers and storms progressing across the state. This line will intensify as it moves across eastern NY during the afternoon. As the line of storms intensifies isolated portions of the Capital District and Mid Hudson Valley could receive up to two inches, with generally ¼ to 1 inch across the rest of the state. High temperatures will generally top out in the mid 70s to mid 80s. Friday will start off with temperatures generally in the 60s. Clear conditions can be expected. Temperatures should top out in the mid 80s up the Hudson Valley with mid 70s elsewhere. Saturday showers will develop throughout the day from west to east. Highs across far western NY along the Great Lakes will be limited to the lower 70s due to cloud cover throughout the day. Further east, clouds will take longer to build in, and so temperatures will rise further with portions of the lower Hudson Valley reaching the mid 80s. Morning lows will generally be in the lower to mid 60s. Precipitation totals should remain under half an inch. Sunday will see the potential for showers across western NY. Precipitation looks to be below ¼ inch. Morning lows will range from the upper 50s to lower 60s. Highs will range from the upper 70s across the west to upper 80s across the east. Monday there is again a slight potential for showers across western New York. Morning lows should range from the upper 50s to lower 60s with highs in the 80s. Tuesday will be generally partly cloudy across the state with a few scattered showers possible. Lows in the lower 60s, with highs in the 80s. Wednesday looks to be sunny and dry with lows around 60 and highs ranging from the upper 70s to upper 80s. The five-day precipitation amounts will range from ¼ inch across central NY to 1.50 inches across eastern NY. The 8-14 day outlook (Aug 6 – Aug 12) features a 40% to 60% of below normal temperatures statewide, and normal to slightly above average precipitation.  The Drought Monitor has remained the same from last week. Moderate drought conditions are no longer present across the Hudson Valley, and are now limited to Long Island.
Maps of 8-14 day outlooks:
National Weather Service watch/warnings map:
NRCC Drought Page which features the US Drought Monitor map (updated every Thursday):
New Video on IPM for Potato Leafhopper in Alfalfa.
The NYS IPM Field Crop Team has a new video on IPM for potato leafhopper in alfalfa. It focuses on proper identification, monitoring and thresholds. It also gives management option for this insect pest. The video is located at the NYS IPM You Tube Channel: https://www.youtube.com/watch?v=8BIZYTq7Zec
Western Bean Cutworm Update 7.30.15
Keith Waldron, NYS IPM
Western bean cutworm trap catches took another quantum leap this past week with 3X as many moths caught this week than last. Higher moth captures more often found in western and northern county than southern or eastern locations. See summary table below.
Monitoring fields for WBC egg masses:
As trap accumulations approach 100 moths per traps risk of WBC infestation increases and field monitoring for egg masses and young larvae is recommended. Pre-tassel corn is the preferred host for egg laying WBC moths. Egg masses will be laid on the upper surface of leaves close to emerging tassels including leaves in the whorl. Check 10 – 20 consecutive plants in at least 5 random locations in the field. Threshold for field corn is 5% of plants with WBC egg masses. Egg masses are typically laid on upright leaves or those just beginning to lay over. I usually check top 4 leaves.
If leaves are oriented towards the sun you can see the egg masses better on the top side of leaf or if looking at the bottom surface of leaves look for a shadow of an egg mass on the upper surface of the leaf. WBC eggs take ~5 – 7 days to hatch turning purple 1 – 2 days prior to hatch. Newly hatched larvae initially feed on their egg case and then make their way to silks or ears. If suitable food sources are not found the larvae will starve.
Several video’s are available on-line on how to monitor for WBC egg masses in corn. https://www.youtube.com/watch?v=cH-yVeDuUM0
For dry beans it is suggested that fields be monitored for signs of pod damage when nearby WBC trap catches approach 100 WBC’s per trap or local corn fields reach threshold. Further details regarding monitoring for WBC can be found in the Weekly Pest Report (http://blogs.cornell.edu/ipmwpr/2014/07/25/nys-ipm-weekly-field-crops-pest-report-july-25-2104/). Pictures of WBC larvae and moths including look-a-like moths and larvae can be found at: http://www.msuent.com/assets/pdf/07WBCID.pdf and http://www.cornpest.ca/index.cfm/wbc-trap-network/wbc-scouting-and-training-material-presentations/wbc-and-its-look-alikes/
|Avg WBC / Trap||0.0||0.1||0.2||0.6||2.0||16.7||55.9|
|> 0 WBC||0||2||2||15||30||49||47|
|% Traps Catching||0.0%||10.5%||6.9%||34.9%||53.6%||89.1%||94.0%|
|Accum Total for week||0||2||7||34||144||1063||3856|
Average Western Bean Cutworm moth captures per location 2010 – 2015 by month
Western Bean Cutworm moth captures by week
For information on additional weekly WBC trap collections see the Sweet Corn Pheromone Trap Network Report: http://sweetcorn.nysipm.cornell.edu/2015/07/28/wny-sweet-corn-trap-network-report-7-28-15/
A Nebraska entomology prediction model has tied western bean cutworm moth emergence to accumulated degree days using a base temperature of 50 F and a starting date of May 1st.
The moth emergence model is:
Degree-day accumulations in relation to percent moth emergence (begin May 1, base 50°F).
|Accumulated Degree-Days||% Moth Emergence|
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
*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.
*Monitor grain fields for growth stage, disease and lodging 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 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
* 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 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