Abstract
Abstract Insecticides were applied to 6-10 year old Scotch pine in 3 fields of a commercial Christmas tree plantation in Jackson County, MI. Sprays were applied to the stem and large branches of trees at a rate of 300 gpa with a CO2 powered backpack sprayer. Efficacy of treatments was determined using a CRD with 15 replicates per treatment (75 trees total). Trees treated with Dimilin 25W, Dimilin 25W + oil and Lorsban 4E were sprayed on 19 Apr 1994, to coincide with first larval activity. Trees in a fourth treatment were sprayed on 13 Aug 1993 (to coincide with adult mating) and 19 Apr 1994. The number of ZPM attacks was determined in Aug 1993, prior to spraying. Post-spray attacks, characterized by soft, oozing pitch masses, were recorded for each tree on 7 Jul and 9 Jul 1994.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
