Please ID this. Poisonous? edible?
Amanita vaginata, the grisette, or a close relative. Google it. The striate margin and unattached gills are characteristic. On the top of the cap are remnants of the universal veil and you should be able to find remnants of the corresponding volval bag at the base of the stem. Edible but not tasty. Don't eat Amanitas unless you really know what you're doing.
Here is a link that might be useful: grisette
Thank you very much. It's very nice to know what's growing in your lawn. Found three more today.
I will not be eating any mushroom unless I have taken some formal training and go with someone with lot's of real experience.