Notches, Nibbles, and Scalloping

This is an adult pea leaf weevil feeding and they love faba beans and peas.

Actually, adult pea leaf weevils are hard to spot, they are brown, about the length of a pencil eraser, have a short snout and like to play dead.

They just fly right in, from kilometers away or may walk short distance. Other cultivated and wild legumes are also host plants for the adult pea leaf weevils (e.g. alfalfa, beans, clover, soybeans, lentils, lupins, and vetch) . Economic damage only occurs in field peas and faba beans. They may nibble on the leaves of dry beans, lentils, soybeans and lupins but such feeding does not cause economic damage. Adults overwinter under the snow in road side ditches and shelterbelts. They will also feed in any kind of bean, alfalfa or clover crop late in the growing season and then overwinter in these fields. The more rain and snow we get the more pea leaf weevils we are likely to see. With our early hot dry spring, pea leaf weevils got an earlier start than usual, and they tend to become active in waves which makes them hard to control.

“Unless something drastic happens, like a major change in precipitation, the chances are good that areas with high weevil densities last year could have high densities again this year,” said Meghan Vankosky, an entomologist with Agriculture Canada in Saskatoon

Research done around Swift Current, Sask., demonstrated that populations of pea leaf weevils completely crashed when there was a period of dry weather. It’s possible that the larvae cannot burrow through the soil crust, or they die on the soil surface when the weather is hot and dry.