I've got a front lawn that's 50% crabgrass and broad leaf weeds. In the back I've got a little vole damage, grubs, and maybe 10-20% crabgrass/weeds. I've read that pre-m should not be put down until the soil is between 50°F and 55°F for at least 3 days. My digital thermometer stuck in the ground about 4 inches says it's about 48° here in northern NY. How deep is one supposed to measure the soil? I'm assuming the deeper you go, the cooler. I have to get rid of the crabgrass out in front yard, but if I put down the pre-m, can I or can't I put down seed this year? If I can seed, how long do I need to wait to do it? The vole/grub area in back is mostly bare except for a good deal of crabgrass. The dog killed the voles. Now what do I do first in this area? pre-m, reseed, grub control, what? I've already raked out the mounds that the voles left, and put down some soil in the deeper trenches.