ARMY WORMS ARE HERE AGAIN

ARMY WORMS ARE HERE AGAIN

 

I thought I published this a week ago but something went wrong. 

The alfalfa caterpillar and army worm complex has flared up in alfalfa fields. If you don’t have them yet you will. Alfalfa caterpillar is that green velvety green with a white stripe down both sides. The smaller instars don’t have the white stripe; if you are waiting to see the white strip you have really waited to long they are getting big by then. These insects have adopted themselves to our normal cutting cycle and are the yellow butterflies (adults) flying in front of the hay swather as cutting.

Army worms complex have a variety of caterpillars depending on which species. We have them all so it is really academic as to which one is predominate this year. If you go into your field and use an insect net in a normal sampling pattern and find 10 caterpillars or more per sweep you need to be considering spraying. I know the publications out say 15, but my experience in the Pecos valley is that is too late. I go with 10. Depending on when you are plan to cut will determine which insecticide you want to use. Lordsban, Mustang max, Steward, Silencer, Cobalt Baythroid Pounce are all labeled for Alfalfa caterpillar complex. New Mexico had a 24 C use permit for Confirm, Tracer, and Spinosid AI products.

http://aces.nmsu.edu/pubs/_a/A334.pdf