After the first frost, there are few mushrooms to harvest until spring. Then, in Spring, mushrooms flourish again. This year, the fall mushroom crop has continued late into the season because it has been so warm. If you gather wild mushrooms, look at each mushroom very carefully. Be certain that it is the variety you are familiar with, and that it is safe.
Many poisonous mushrooms look similar to edible ones.
If you notice anything not familiar in a mushroom, do not eat it. Cooking mushrooms will not eliminate the toxins that can be dangerous. Some very poisonous mushrooms that grow in Washington look very much like edible mushrooms that grow in Asia or other parts of the world. If you are used to picking wild mushrooms in other countries, please do NOT assume that the same safe varieties grow in this area even if they look similar. Buy it from a store or in a restaurant that has purchased it from experts.