Mushrooms can come in a lawn as suggested, but most times its because something has been buried --like old wood during construction, or a tree root has begun to deteriorate, the mushroom is just the fruit of the fungus that`s been produced. They pose no problem to your lawn....they could pose a problem should a child play there and put a toadstool into his mouth....but otherwise, why not enjoy them. Play golf......take your 9-iron or a sand wedge, and go out and practice. No golf...a hockey stick will do fine in the hands of your teenager. Get a kick out of them for your own enjoyment.

The infestation of mushrooms indicates an imbalance of soil microorganisms allowing the fungus to dominate. I would top dress the lawn with compost and apply aerated compost tea regularly. This will protect your lawn since it isn't yet infested with the fungal overgrowth next door. The spores are in your area though so you will want to deal with this as soon as possible. I personally would not recommend fungicide but if it is used, it should be followed by compost and compost tea to inoculate the soil with beneficial microbes. You can't overdose with compost tea so if you are inclined, make some and apply it every week after mowing. Also make sure you leave the clippings on the lawn so they can feed the soil microbes. This will help with the lawn health. Here is a link that might be useful: How To Make Aerated Compost Tea

Most mushrooms live on dead or dying wood and dying roots, so it's hard to see how they could kill the grass. I suppose if the mycelium is really thick it could use nutrients that might otherwise be available to the grass, but I've not seen it happen. I get about three kinds of mushroom-type fungi coming up in my lawn and I always welcome them. They don't seem to hurt anything, and are always beautiful. I think it's a matter of taste. Lots of folks don't want ANYTHING in their lawn. Lainey

Moss in your yard is an indication that you most likely have to much shade and/or moisture. Fertilizer will improve your turfgrass stand, reducing the visibility of the existing moss, however it will have no effect on your moss problem. I would suggest if you are irrigating, reducing the amount of water applied in areas where moss has established. If possible I would also identify shady areas where moss has developed and consider trimming or thinning tree limbs to decrease the over all amount of shade. There are a number of products available for moss the include, TerraCyte, Junction, Daconil Ultrex, and Quicksilver. However these products will only provide a temporary solution to the problem if the environmental factors, shade and moisture are not addressed.