How can you prevent mushrooms from growing in your yard?

Question

How can you prevent mushrooms from growing in your yard?

Answer 1

You don't they break down all that old grass that you didn't bag into top grade soil.If you use a fungicide to get rid of them you might start getting worse molds that can kill your grass

Answer 2

Mushrooms are beneficial but if you want to get rid of them simply keep the soil a bit drier.  

Answer 3

Although sometimes unsightly, mushrooms are the fruiting structures for many important and beneficial fungi in the landscape.  As the previous answer stated some are decomposers, breaking material down and returning nutrients back to the soil.  

Others actually form a symbiotic relationship with the plants that they live on.  They effectively increase the surface area of a plants roots' allowing it to uptake more nutrients and water.  The mycorrhizae in return receive all the nutrients they need.  

In fact in places where the soil has been disturbed and the beneficial microorganisms killed off plants won't grow well even if all the nutrients and water are there for the taking.  They need the mycorrhizae to thrive.

So don't apply a fungicide just to get rid of mushrooms.  There are a few specific turf diseases caused by fungis that warrant a fungicide application, otherwise it does more harm than good.