Sorry to hear about the issues with your blue spruces. Sawfly larvae typically emerge in the spring/early summer, depending on what type they are.
Diatomaceous earth can be used to help with sawfly larvae. When insects/larvae crawl through it, diatomaceous earth damages the outer layer of their bodies and will kill them quickly.
You will want to spread it around the base of your plants when you see the first signs of them, but since it is a powder, it will need to be reapplied after it rains or during humid weather.
You can also apply it to the directly to the plant as a secondary approach.
Hope this helps! And good luck with getting rid of you pest issue.
Hi Susan,
Sorry to hear about the issues with your blue spruces. Sawfly larvae typically emerge in the spring/early summer, depending on what type they are.
Diatomaceous earth can be used to help with sawfly larvae. When insects/larvae crawl through it, diatomaceous earth damages the outer layer of their bodies and will kill them quickly.
You will want to spread it around the base of your plants when you see the first signs of them, but since it is a powder, it will need to be reapplied after it rains or during humid weather.
You can also apply it to the directly to the plant as a secondary approach.
Hope this helps! And good luck with getting rid of you pest issue.