Volume 16 -Number 11
View from the Field
Potato Leafhopper (Empoasca fabae)(PLH) populations in alfalfa are extremely high across the state. Many fields are reporting PLH over threshold and showing damage. In one field I had an average of 400 PLH nymphs per sample. This is a VERY high infestation rate in alfalfa. Make sure to check your fields ASAP.
We have a training video on IPM for Potato Leafhopper in Alfalfa (8 minutes long). The video helps you understand how to monitor and determine thresholds for potato leafhopper. It also has IPM methods of control of potato leafhopper including harvesting early, planting resistant cultivars and insecticides. IPM For Potato Leafhopper in Alfalfa
I am finding black cutworm damage to field corn at the Cornell Farm in Valatie. A few weeks ago we had 60 black cutworm moths in a pheromone trap at the farm. The field still had less than 5% damage. If you have later planted corn and the field had weedy grasses you might want to check for black cutworm damage.
NYS Western Bean Cutworm Report for Field Corn 2017
The 2017 Western Bean Cutworm (WBC) Monitoring program is underway and WBC moth collections have begun. Western Bean Cutworm (WBC) is an emerging pest in NY with the potential to cause substantial damage to corn, Zea mays and beans, Phaseolus vulgaris. WBC is native to North America and has historically been a pest of corn and dry beans in the high plains region of the western US. WBC larvae feed on developing corn kernels, bean pods and seeds. Larval feeding damage causes direct yield losses and can increase subsequent risk of ear mold issues including infection by mycotoxin producing fungi.
WBC moths were first confirmed in Pennsylvania and western New York in 2009, one year after they had been detected in Ontario, Canada. Extensive monitoring during 2010 – 2016 has determined that WBC moths are well distributed across these areas and have expanded their range into Quebec and parts of Northeast.
NY WBC populations have increased annually since statewide until last season. In 2016 WBC data was available from 63 traps across NY. A total of 17,450 WBC moths were collected in 2016, compared to 20,844 collected in 2015, and 11,353 collected in 2014. On average, higher WBC counts have been observed in northern and western counties with the majority of high captures occurring in locations north of the NYS thruway (Interstate 90). The number of moths caught on average per traps in 2014 was 177 moths/trap and in 2015 was 266 moths/trap. Note that while the total number of moths caught were down from 2015 the 2016 the average of 277 moths/trap was higher than in 2015.
There were reports of WBC causing economic damage in NY in field corn in Northern NY in 2016. In some cases 20% of the ears of corn were damaged in field corn. WBC also caused damage to certain Bt hybrid corn cultivars in Northern NY.
Table 1. New York Western Bean Cutworm 2010 – 2016 Collection Data Summary*
|Avg. No. WBC / Location||13||23||42||66||117||266||277|
|Range in Totals||0 – 99||0 – 165||0 – 344||0 – 853||0 – 1019||0 – 1688||0-1662|
|Peak Flight||2-Aug||2-Aug||25-Jul||21-28-Jul||3 – Aug||2 – Aug||Aug 7|
*Data compiled from WBC trap catch information provided by field corn, sweet corn, and dry bean monitoring networks across NY. In 2016 the data is just related to field corn.
To keep watch on WBC populations and help determine this season’s risk of potential impact WBC pheromone traps are again being monitored across the state by a dedicated network of cooperative extension, agricultural consultant and producer volunteers. WBC trap deployment began in June. WBC numbers are beginning to trickle in indicating moth emergence has begun. Peak WBC moth flight activity is anticipated towards the end of July or early August. Accumulated moth captures as of 7.14.17 from field corn monitoring sites are shown below.
|Avg WBC / Trap||0.0||0.4||0.8||1.5|
|> 0 WBC||0||4||7||13|
|% Traps Catching||0.0%||25 %||25.5%||50%|
Western bean cutworm updates for sweet corn and dry beans will be available at this blog throughout the season and the NYS IPM Sweet Corn Pheromone Trap Network Report.
Degree Day Models for Field Crops across New York
Ken Wise, NYS IPM
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|
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
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.
*Monitor spring small grains for signs of Fusarium Head Blight, foliar diseases
*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 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
* 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