What can I use on webbing caterpillars and borers on a grevillea
I have a large native garden, 1 acre with many rare grevilleas & other natives. I have experienced many frustraions with webbing caterpillar & borers over the years. It is getting worse. I was away for 6 weeks & came back to find some of my grevilleas almost dead from borer attack. Webbing caterpillars seem to hide underneath larger shrubs % are not noticed until damage is severe. I have actually had to burn some shrubs because the damage was so bad. Help please. Regards, James
Webbing caterpillars can cause quite severe damage and often go unnoticed for some time. I have found that Yates Success Ultra which controls a range of caterpillars is effective against the webbing caterpillars. Apply it in the late afternoon and the caterpillars will feed later that night. Success is derived from soil microbes which affect the caterpillars. They will stop feeding immediately however they may take a few days to die. Re spray every 5-7 days or after rain. We do not have a product that will control borers so you may have to resort to pruning or inserting a thin piece of wire into the borer hole.
Answered: 13 Feb, 2012