Q. The area where mushrooms grow best gets full sun all day. I had my almond tree removed. The roots were ground out, also a year ago. I think the mushrooms came with the dirty lawnmowers from the people that did my lawn last year. But two days ago, I poured straight vinegar on them. Yesterday they looked dead. But just to be safe, I bought some more cheap vinegar to pour over them if there are new mushrooms. I turned the lawn sprinkler off for 2 days so far. No more water! These were mushrooms after they lost their “caps”. Notice how mushrooms grow best with some food (woodchips), water (rain or irrigation) in contact with soil. A. Mixing soil with wood chips, together with water, is the perfect environment for mushrooms to grow during warm weather. Using a “stump grinder” and mixing those woodchips with the soil, in the presence of water, makes mushrooms. This is why mushrooms, in the presence of rotting wood, magically “appear” after a rain. The woodchips that are constantly being irrigated are gone. The wood has decomposed. The wood did amend the soil, but the small “chunks” of wood (woodchips) are gone. They were “dissolved” or decomposed. But not woodchips exposed to the rain! Those are in usually dry areas. Mushrooms (and the mycelia produced) are part of the decomposition process. Too bad some are disgusting or toxic and cause dogs that eat them to vomit. Mushroom are what we see after it rains. Just like flowering plants that flower after a rain, mushrooms “flower” after a rain as well. Except we see mushrooms. Underneath those “caps” are gill slits that release spores or seed. Some mycelia don’t produce mushrooms but many do. It can get quite complicated. The only things missing compared to plants is light (mushrooms grow best in darkness) and roots. Instead, mushrooms have “mycelia” (a “mycelial mat”, as its called, which spreads wherever mushrooms grow). Just like plants, the first to grow are the mycelia or “roots” of mushrooms. The mycelia are responsible from breaking down the “wood” and taking up nutrients. If there is enough water present (rain or increased humidity) then appear the mushrooms. Oftentimes mushrooms are not visible until after it rains but the mycelia (if there is some irrigation) are still responsible for getting the nutrients out of the woodchips. They are digesting wood even if we don’t see “mushrooms”. Mushrooms are just there for reproducing. My guess is that the mushrooms were not brought in by the mowers, perhaps the spawn (mushroom “seed” or mycelia) were but not the mushrooms themselves. Mushrooms are just evidence that sex was involved. Once established mushrooms (mycelia) continue to feed on decaying wood until the wood has decomposed and is gone. Their food is then gone. Some mycelia have a “waiting stage” and others die. But the soil is improved and becomes darker. Mushrooms are easy to kill. They last about two or three days when it’s warm. Next time use a rake and knock them down. Or let them have some fun! Save your vinegar, along with the seasonings, for pickling.