I have a group of mushrooms that have appeared under my birch and conifer trees. I am attaching pictures. Is this the common meadow mushroom, agaricus campestris, or something poisonous?
Clackamas County Oregon mushrooms
This is a species of Agaricus, possibly the horse mushroom Agaricus arvensis. The meadow mushroom does not have such a well developed ring (annulus) on the stalk. If it smells like Phenol then it is one of a poisonous group of Agarics which cause gastrointestinal distress if eaten. However, they are not deadly poisonous. Edible species this size tend to have a sweet almond odor. I advise against eating any mushroom without first consulting a local expert.