Strange round growths
For years, my lawn has been plagued by hard round balls that grow at random. Please see attached. What are these? A form of mushroom? Does their growth signal something lacking in the soil?
This is a fairly common lawn mushroom. It can get quite hard, but it does not indicate a problem with your soil. Like all mushrooms, it is growing on dead organic matter. Probably a dead root or construction debris under the soil surface. There are no products that will eliminate it. Best to just let nature run its course. Most of it is composed of mycelium (like tiny roots) in the soil--the part you see is a "fruiting body." You can dig up that if it is a problem. The mycelium will remain. When the organic matter in your soil is decomposed, the mushrooms will disappear.