Trap Trees for Control of Dutch Elm Disease

Abstract

Diseased or unwanted elms treated with cacodylic acid or monosodium methylarsonate (MSMA) by injection or topical application to axe or chain saw cuts are colonized by elm bark beetles, but herbicide-induced drying of the bark suppresses brood production. Treated trees need not be removed for the sake of Dutch elm disease (DED) control and their wood can be utilized for fuel and other purposes. Experimental and operational applications of this technique have been followed by reduced rates of DED infection. Time required to treat a tree averages about 15 min and per tree cost of materials ranges from a few cents to about $10. A one or two person crew working full time during the growing season can apply the trap tree technique to all diseased trees in a population of about 100,000 elms.