That's an excellent question to ask your allergist/health-care provider.

I usually pull them out and throw them in the compost pile, but I don't know if it really matters. I found some in the mulch nect to my daughters sand box that were rather phallic looking it was unlike any mushroom I had ever seen. I definitely felt I needed to remove it before my neighbors started making too many jokes about what I was growing these days.

I just kick them over with my shoe. By the next day they are brown and we just mow them and mulch them with the next mowing. They aren't harmful. Some of them are pretty cool looking. I was working in my garden by the front walk last weekend and I had 2 huge ones growing among the rain lilies. A lady walking down the street remarked how beautiful they were. She thought I was cultivating them. One persons unsightly could be another persons beautiful. Made me look at them in a new way. I let them stay till they turned brown, and then picked them out and threw in the compost.

My kitchen cabinets were finally (one year later) delivered on Monday but are not yet installed. The SW shiitake color is PERFECT! My inspiration was also Devol mushroom but needed to go with a SW paint color. The Shiitake is similar but is slightly less gray and actually has the teeniest green/beige undertone but can only be described as a greige. The SW shiitake color as shown on its website is SO off. Someone said it looked like pantyhose and on the website it truly does. The actual color is greige, greige, greige. Hope that helps.