Chipmunk/Squirrel/Mouse? Control?

Looking for SOMETHING that is not a trap (because I don't want to catch the birds). Some kind of smell or deterrent to keep chipmunks/mice from digging up and eating my seedlings! I have already been putting coffee grounds out. Would diluted urine work?

Hi Almond,
What sort of area are we talking about? Open garden? Greenhouse?

And is killing the rodents acceptable to you?

Most smell based deterrents do not work long term and most also get washed away when it rains. Also, smell based deterrents (or any deterrents really) will only work based on how much the animal wants or needs what is there. A starving animal will endure a lot to get food. An animal that is comfortable and getting everything it wants will also put up with a lot.

My first thought is to cleanup the area. Cut the grass short, rake up any leaves and pick up any piles of stuff. Take away any hiding places to make it more dangerous to get to your plants.

I know you said you do not want a trap. If this is because you don't want to kill them... then ignore this next piece. If it's because you don't want to also hurt the birds, then let me make a suggestion. I've heard really good things about the Good Nature traps. They are expensive, but would be highly unlikely to attract a bird and kill it. https://goodnature.co/ (I have no affiliation, I just think they built a really good trap).  

If your opposition to using traps is just that you don't want to catch birds, yon can put mouse traps under a small box with an opening for the critters to enter. Mice and such can still get in, birds can't.