Two mushrooms I photographed in Shindagin Hollow State Forest a few miles from my farm.
@UP8 it's possibly Amanita jacksonii https://www.mushroom-appreciation.com/caesar-mushrooms.html
@mjambon i don't think that the cap opens up when it gets bigger
my Polish relatives taught me to pick quite a few Boletus (no gills) mushrooms but never anything red
@UP8 striations on the cap are a key feature for this group of amanitas (section caesareae).
@UP8 by the way, if you're adventurous and finding many A. muscaria, they can be prepared to be safe to eat by parboiling in plenty of water 5+ min twice and discarding the water each time. (some people are interested in the psychoactive effects but prep and use are trickier)
@mjambon I know people who eat A. Muscaria and swear they like the expereience; my grandfather though told me to stay away from them and told me they are called in Polish "Mohu Mori" which means "Death to Flies"
@UP8 my main problem is to find them where I live (a drier area in northern California) but I think I found a promising area to explore in the fall.
@mjambon they are all over New England and New York
@UP8 I will find them, I'm not giving up!
@mjambon now that i think of it i have seen red mushrooms that look like the photo in the web page you linked in that area, and not the very common Muscaria