Do they have a smaller area for smaller dogs to play without getting trampled by big dogs? My dog is scared of bigger dogs because she was just ataked by one! She was not injured but then a nice big doggy came over to greet her and she was scared!

It's one space, but it's so large you could keep your dog away from the large ones.

Just updating the answers here - there are now two separate areas, one for smaller dogs / puppies and the larger area for the big dogs.

There is an ongoing project to separate the multiacre space into two distinct areas for large and small dogs. This should be complete by spring 2020. In the meantime there is only one undivided area, but it is large enough to keep your dog away from the large actively playing dogs, especially if you come at non-peak hours.

I have the same problem with 1 of my small ones and unfortunately the big dogs would follow him around and scare the wits out of him so we stopped going.

They're renovating the park starting at the end of this year to add one! But as of right now no, and the average dog size at the park is very large. You could try Lafayette park in Pacific heights - the neighborhood there has much smaller dogs on average.