View from the Field
Once again there is a line-up of diseases this week. In corn we are finding northern corn leaf blight, northern corn leaf spot, gray leaf spot and various kinds of stalk rots.
One disease found at the Cornell Research Farm this fall was northern corn leaf spot. The symptoms are linear narrow lesion about a 1/8 to ľ inch wide. They range from a Ĺ to ĺ inches long. They are grayish-tan and have a pigmented border. The lesions exist between the veins and are linear in appearance. The fungus is Bipolaris zeicola (Helminthosporium carbonum) and has five different races that can infect the plant. The fungus overwinters on corn crop residue from previous years.
Northern Corn Leaf Spot. Photo by Ken Wise, NYSIPM.
Management of Northern Corn Leaf Spot.
- Plant corn hybrids that are resistant to Northern Corn Leaf Spot
- Use a shorter rotation of 1 to 2 years for corn
- Plow under residue to reduce fungi in the field.
- Fungicides are effective at controlling the disease but is rarely economical
In soybeans there are reports of white mold and soybean vein mosaic virus this week. Most of the reports of soybeans with white mold have come from Eastern NY. Soybean vein mosaic virus is being found statewide and in most fields.
Keith Waldron reports finding bean leaf beetles in soybeans near Waterloo, NY. This insect pest is relatively new to New York.† For more information on bean leaf beetle please see View from the Field, 9-4-12.
I found English grain aphid in triticale this week. English grain aphid is one of the aphids that can transmit barley and wheat yellow dwarf. Triticale can be infected like all other cereal grains and even grasses. Triticale does not always show symptoms like you might see on wheat and barley.
September 20, 2012
Jessica Rennells, Northeast Region Climate Center, Cornell University
Last week temperatures ranged from 0 to over 3 degrees above normal for most of the state.† Rainfall amounts ranged from 1 to 2 inches for most of the state; western NY had less than an inch; the Catskills and surrounding areas had over 2 inches. The Base 50 growing degree-days ranged from 50 to 100, les than 50 in the Adirondack region.
Today will be sunny with temperatures in the upper 60ís and low 70ís.† Overnight temperatures will be in the mid 40ís to low 50ís. Friday will be mostly cloudy with highs in the low to mid 70ís.† Some scattered showers are possible as a weak cold front moves over the state.† Lows will be in the low to mid 50ís. Unsettled weather over the weekend; westerly winds could bring lake enhanced showers. Saturdayís temperatures will range from the upper 60ís to mid 70ís with scattered showers and thunderstorms possible as a stronger cold front moves through.† Lows will range from the mid 40ís to mid 50ís. Sunday highs will be throughout the 60ís with scattered showers.† Overnight temperatures will be in the upper 30ís to mid 40ís. Monday will partly sunny with temperatures in the 60ís.† Lows will be in the low to mid 40ís. Tuesday will be mostly sunny with temperatures in the mid 60ís to low 70ís.† Lows will be in the 40ís. Wednesday temperatures will in be in the mid 60ís to low 70ís.† Lows will be in the mid 40ís to low 50ís.
The five-day precipitation amounts will range from 1/10 of an inch to 1 ľ inches. The 8-14 day (Sept 27-Oct 3) outlook is showing normal temperatures and above normal precipitation.
National Weather Service Climate Prediction Service Maps of 8-14 day outlooks
National Weather Service Eastern Region Headquarters watch/warnings map
NRCC Drought Page which features the US Drought Monitor map (updated every Thursday)
Western Bean Cutworm
The Western Bean Cutworm (WBC) trapping season has come to an end for 2012. Counts this week remained essentially the same as last week with most sites still in operation reporting “0” moths.
What’s next for WBC larvae?
As WBC larvae mature they will stop feeding, drop off their hosts and burrow into the soil to overwinter. In late summer and early fall, 6th instar WBC larvae drop off their hosts and burrow into the soil, where they construct earthen chambers where they will overwinter. These soil cells are about 5-10 inches beneath the soil. Sandier soils allow larvae to penetrate deeper into the soil profile. The underground overwintering location provides greater protection from winter temperatures and tillage equipment and increases overwintering survival. The larvae remain in their pre-pupa state throughout the winter, then pupate and complete development to moths the following summer. Surviving insects should begin to appear in our moth traps about the last week or so of next June.
Western Bean Cutworm Monitoring Highlights 2012:
- Total number of WBC (male) moth catches was 3,458, more than 2X last year’s catch.
- Peak WBC flight this year was about 1 - 2 weeks earlier than that observed in 2010 and 2011 (August 2) See figure below. Earlier emergence and activity probably related to the warm temperatures in spring and early summer.
- The majority of WBC moths captured statewide were in very good condition indicating there are locally overwintering populations. These populations appear to be relatively small to moderate in size with the majority of locations catching less than 50 WBC moths / trap.
- Several western and northwestern NY sites had very high captures this season (> 150). A high percentage of moths captured in these high count locations had damaged wings suggesting they had travelled some distance and were likely migrants.
- Very few egg masses were found this season (Franklin County) and none of those fields were over threshold (field corn: 5% field infestation with egg masses and/or small larvae). There have been reports of WBC larvae in sweet and field corn ears.
- So far WBC economic damage has not been detected this season although it is still quite early as dry bean and corn harvest has only just begun.
We are very interested in documenting any economic impacts associated with western bean cutworm this season. If you believe you have WBC larval damage and suspect economic losses we would like to hear from you. Please contact your local Cornell Cooperative Extension field crops educator.
* Emergency contact information ("911", local hospital, Chem. Spill emergency contact, other) posted in central posting area
* Maintain crop records by field, including variety, planting date, pesticides used, nutrient inputs including manure, etc.
* Watch for any patches of herbicide resistant weeds, weed escapes
* Monitor fields for plant vigor, growth stage, late season pest issues (European corn borer, foliar diseases, stalk rots, ear molds, nutritional deficiencies, vertebrate damage)
* Monitor for weeds, note presence of "who", "how many" and "where"
* Monitor reproductive stage corn fields for foliar diseases, lodging issues, corn ear damage (insect pests and ear molds and other diseases)
* Prepare storage areas to accept upcoming harvest
Alfalfa & Hay:
* Monitor alfalfa seedings for weeds, insects & diseases.
* Check regrowth of established alfalfa stands for potato leafhopper, weed and disease problems.
* Storage areas cleaned and ready to accept incoming harvest
* Monitor fields for diseases such as white mold; natural enemies and weed escapes
Dairy Livestock Barn Fly Management:
Barn fly issues tend to spike when fall temperatures drop and flies seek warmer locations. To avoid establishment of fly populations pay close attention to barn sanitation and other cultural practices to minimize fly breeding habitat.
* Sanitation, sanitation, sanitation - clean animal resting areas, feed throughs, minimize source of moist organic matter i.e. fly breeding areas in barn and in adjacent animal loafing yard
* Check water sources, drainage, roof gutters for leaks and potential overspill
* Continue fly monitoring: install "3X5" index card fly speck monitoring cards throughout barn
* Install/refresh/replenish as needed: fly tapes, insecticide baits, natural enemies (parasitoids)
Dairy Livestock Pasture Fly Management:
Pasture fly issues tend to drop significantly when fall temperatures drop, particularly after the first frosts. House, stable and perhaps some horn flies will seek warmer locations such as barns.
* Monitor animals for presence of pasture fly pests. Treatment guidelines: Horn flies (50 per dairy animal side, 100 per side for beef cattle), face flies(10 per animal face), stable flies (10 per 4 legs). See IPM's Livestock page.
* Consider installing biting fly traps to reduce horse, deer and stable fly populations.
* Check temperature, moisture, pest status of bin stored small grains
* Keep areas around storage bins and silos clean and mowed
* Check areas around storage bins and silos for vertebrate tunneling
* Check temperature of recently baled hay in hay mow
* Clean grain bins target for use in storing upcoming soybean or corn harvests
* Note any repairs needed for recently used equipment: tractors, tillage implements, planters, sprayers, etc. as they are cleaned and serviced.
* Service hay harvesting equipment as needed.
* Calibrate manure spreaders - maintain records on amount spread per field
PESTICIDE EMERGENCY NUMBERS
Emergency responder information on pesticide spills and accidentsÖ
CHEMTREC - 800-424-9300
For pesticide information
National Pesticide Information Center: 800-858-7378
To Report Oil and Hazardous Material Spills in New York State
NYS Department of Environmental Conservation Spill Response - 800-457-7362 (in NYS), 518-457-7362 (outside NYS)
Poison Control Centers
Poison Control Centers nationwide -† 800-222-1222
If you are unable to reach a Poison Control Center or obtain the information your doctor needs, the office of the NYS Pesticide Coordinator at Cornell University, 607-255-1866, may be able to assist you in obtaining such information.