If you have squirrels in the area, they of course have excellent climbing ability, and one of their behaviors is to prune the tips of tree branches off, presumably in the course of feeding...which sounds similar to what is being done to your tomatos. After one particularly bad spring, my whole neighborhood was littered with branch tips thrown down by squirrels.

Squirrels and chipmunks also both dig random holes here and there in the search for food, or--in the case of chipmunks--preparatory to making a nest. If you used mushroom or any other form of loose mulch, you may have imported a mouse, rat, or something else along with it, in which case it is probably living in the garden itself. Therefore, the protective screening would of course not solve the problem. Repellants might do a better job if that is the case, but if your garden is the only feasible home in the area for the critter, it will probably resist leaving.

I know that chipmunks can climb up an entire sunflower stem to eat the sunflower's seeds; maybe other rodents besides squirrels also have climbing abilities.

The random nipping and destruction sounds suspiciously like a groundhog (they like to take nips out of things as a sort of turf-claiming thing), but unless you have ever seen one of them around or have a mound with a rather large groundhog-sized hole, you can rule that out, especially in the city.

If your mulch is from a more rural location, I would incline toward the chipmunk theory. They are also quite territorial, and used to demolish the contents of some of my plant pots-- mainly because, I think, they didn't like where I had placed them. Chipmunks like to clear certain areas so they have a clear line of sight. If your mulch was from a more rural location, a chipmunk could have made a burrow in it, and been swept up along with the mulch.

Thanks for the reply.

I also considered squirrels/chipmunks, but didn't think they were nocturnal. The damage is happening between the hours of 1-8 am.

The soil I'm using is mushroom soil. However, I shoveled all that soil into my box shovelful by painful shovelful so if there is a resident in there, it probably got in there after I filled the box.

What sort of repellant do you suggest?

Thanks again for the suggestions!

There's plenty of daylight before 8AM, and the chipmunks will happily climb. There was one climbing up the chainlink just today to get at my finch feeder, and they regularly climb up the tree and the shepherd's hooks to get in the bird feeders.

If your bird netting and/or chicken wire has holes as large as an inch, that's easy pickings for a chipmunk.

I don't have any useful suggestions other than to fill a bird feeder on the other side of the yard with seed and watch to see who comes to eat. If you've got a chipmunk, you'll most likely see it investigate, then attempt to empty your feeder, and you should be able to see where they go.

Hope this is of some use - I know there are others with much more critter experience!

Lynne in Bowie

ps..Voles are entirely possible. If you have dirt enough for a garden, you have dirt enough for critters..

Here is a link that might be useful: This looks like it might be helpful...

Sounds exactly like what squirrels do in my garden and as Lynne suggests, they are up with the dawn and can do plenty of damage before 8 am.

Don't forget, flying squirrels are nocturnal, and they live in Baltimore. I don't know whether they eat off the ground or stick to the trees, though.

opossum maybe???