Eastern New York Field Crops Pest Report, 2002

For 5/10/02:

Alfalfa

Alfalfa in Eastern New York is currently about 10-18 inches in height.

Alfalfa Weevil: Alfalfa weevil threshold before first cutting is 40% tip feeding.

SUNY Cobleskill alfalfa fields are currently at 10% to 30% tip feeding with larvae ranging from 1/8 to þ inch long. There are still adults present and are most likely laying eggs in the stems of alfalfa (May 8).

Kathryn Chabarek, Extension Educator in Dutchess and Columbia County reports 20% or less tip feeding in alfalfa fields (May 8).

Check out our on-line publication, IPM for Alfalfa Weevil. 1.2 Mb pdf file

Clover-root curculio: Aaron Gabriel, Extension Educator in Washington County reports finding several clover-root curculio weevils in alfalfa. Adult clover-root curculio weevils are 1/8 inch long and 1/16 inch wide with short, broad snouts. The adult weevil is brownish-black and covered with grayish hair and scales. Adult curculios chew the margins of leaves leaving C shaped notches. Clover-root curculio larvae feed on nodules, small rootlets, and chew out portions of the main root. As a result of larval feeding on roots alfalfa disease can enter the plant.

Lady Beetles: Hey, lady beetles are back after all that cold weather. The following species of lady beetles were found in 10 alfalfa fields at the SUNY Cobleskill farm: (May 8)

Multicolored Asian Lady Beetle (Harmonia axyridis), native to Asia.
Spotted Lady Beetle  (Coleomegilla maculata), native to North America.
Parenthesis Lady Beetle (Hippodamia parenthesis), native to the North America.
Russian Wheat-aphid Lady Beetle (Hippodamia variagata), introduced from Europe.
Seven-spotted Lady Beetle (Coccinella septempunctata), introduced from Europe.
Cream Spotted Lady Beetle (Propylea quatuorodecimpunctata), introduced from Europe.
Three-banded Lady Beetle (Coccinella trifasciata), native to North America.

The seven-spotted lady beetle far out numbered the other species of lady beetles in alfalfa fields this week.

For more information on lady beetles check out this website: COCCINELLIDAE THE LADY BEETLES

Potato Leafhopper: A challenge set forth: Who will be the first person this year to find potato leafhopper in NY. If anyone in NY finds potato leafhopper in alfalfa before me, I will buy him or her lunch.

Grass

Armyworm: Ken Wise reports finding 5 true armyworm moths per pheromone trap in Schoharie County (May 8).

Kevin Ganoe, Area Field Crops Specialist reports finding 3 armyworm moths in a pheromone trap near St Johnsville (May 7). 

Disease: Aaron Gabriel, Extension Educator in Washington County reports finding diseases on orchardgrass and timothy. Aaron suggests that those of us who monitor fields should be looking at possible diseases in grass (May 1).

Field Corn

Planting: Many acres of field corn are being planted this week. We need to watch for seed corn maggot, wireworm, cutworm, slugs, seedling diseases, weeds, geese and deer. Remember to check plant populations as corn starts to grow, as it is a good indicator of potential pest problems.

Clover: Ichnopterapion virens: Ken Wise reports finding many tiny blue weevils called Ichnopterapion virens in a clover field at SUNY Cobleskill (May 8). This weevil is native to Europe and is relatively new to the United States. Adults are metallic blue, about 3/16 inches long, with a distinctive snout and straight antennae. Adults make small circular holes in leaves of white clover. Larvae tunnel in the runners of white clover and stems of red clover. The economic damage status of this weevil is not known. Here are a few sources of information on Ichnopterapion virens you can view on the Internet:

Picture of Ichnopterapion virens at PSU.

ISCHNOPTERAPION VIRENS (HERBST) (COLEOPTERA: CURCULIONIDAE, APIONIDAE): A PALEARCTIC PEST OF CLOVER, TRIFOLIUM SPP. (FABACEAE), NEW TO NORTH
AMERICA

STAY TUNED There will be more next week!