Well, I guess Bella's allergies weren't as in check as I thought they were. She's been getting hives (or what look like hives) about twice a week. She never seems to be bothered by them, though. She never scratches or otherwise indicates that she's uncomfortable. I'm really glad that we got a new vet who doesn't charge exam fees each time we take the dogs in. I have a feeling Bella is going to be spending a lot of time there this summer.
I just snapped this picture a minute ago, after Bella had been outside for about 10-15 minutes:
Would you say those are hives? I'm not even sure. They're only on the left side of her body. She wasn't lying down in the grass on that side, so I'm not sure why they're only on that side!