Squirrels, voles, lawn grubs. We have all three (I'm in Saint Paul) in our yard. One last application for the grubs this spring and most of them will be gone, and the liquid fence seems to keep the rabbits and hare at bay and for the most part - the squirrels when it's really fresh (eww). The neighborhood mouser helps with the voles (meadow mice) - but not quite enough. We have more trouble with them right now digging tunnels - luckily it's not moles! I "removed" one of them from the yard spring before last and not seen any others yet.

We have been known to livetrap out problem squirrels and relocate them far far away as they are REALLY destructive to my gardens and my Earthboxes (veggies planted in them).

-Marie

I have never seen grass suffer due to walnut allelopathy (toxins). Don't think that could be the problem. And walnut roots aren't particularly surface riddling, like maples for instance. Picturing your lawn "covered" with squirrel holes, now that can't be good. But my guess is that there must be a combination of detriments going on.

Lots of lawn problems for many people this spring. Check out the post about the Yard & Garden News, it has some info, or use this URL: www.extension.umn.edu/yardandgarden/YGLNews/YGLNews.html

I know that my black walnut tree provides sufficient shade to make grass grow sparsely. I'm not aware of any "critter" infestations in my lawn, but I am aware of the shade. :-p