I don't go to dog parks anymore. This is one of the many reasons.

At the most, mounting is a very blatant display of dominance. At the least, it is an annoying and rude behavior, and your puppy should not be subjected to that by completely strange dogs. Would you let a *complete* stranger smother you with a bear hug? Maybe if you knew the person better and were familiar with him/her, you would tolerate and submit to a smothering bear hug. It's the same with your girl. If she knew the other dog well, that kind of behavior would probably elicit play from her. But she doesn't know them and they could be dominating, or they could be playing. The uncertainty alone is enough to dissuade me from dog parks.

I also don't like bringing young puppies to parks because it gets extremely rough and puppies can often turn into prey - especially when you have a pack of dogs in the vicinity. I've seen *many* puppies ganged up on simply because they were small, yelping little packages of fur. In those instances, it was a matter of: the puppy was playing, the puppy got hurt and yelped, and a pack formed to chase the puppy down.

When you're at the dog park, you constantly have to gauge the arousal level. In the case of the pitties and your girl, if you got a hand on the dog's collar but he was still vehemently itching to go after your pup, I would leave the park. Playing dogs will stop and take a break if you restrain them. Dogs whose arousal levels are too high are unable to control themselves. I don't want to be in any situation where any dog is so overaroused that he can't control himself - especially when almost all dogs in that situation are strange to me.

For socialization, find doggie day care centers or trainers that hold socialization meetings. You usually have to buy a card and go on certain days. It's only a few bucks, but the dogs who go there must be friendly and there will be a trainer there to gauge the arousal levels and step in whenever necessary. Also, a single dog walker going to a dog park with 20 dogs is enough for me to immediately leave.