Hey FA, they do grow in second growth for sure. The seem to like really thick, hard to pick ground cover too.
Why don't you pick a few and post up some picks. Make sure you twist them right out, don't snap them off. The shape of the base is a good way to distinguish from amanitas. And if you do any reading on them you will learn that the smell is also very unique. Once you know it, you will smell it even when there are no pines obviously up.