Pensacola News Journal

For: Saturday, June 22, 2002

By: Daniel E. Mullins

Extension Horticulture Agent

Santa Rosa County

Mushrooms Soon to Appear if Rains Continue

The sudden appearance of mushrooms is common in Gulf Coast landscapes. They can literally pop up overnight, resulting in various reactions from homeowners. Questions and comments about these interesting structures range from serious to downright humorous.

Most of the mushrooms in question are the reproductive structures of saprophytic fungi. This group is different from the plant parasitic fungi that cause plant diseases in that they feed upon, and help to decompose organic materials. They are an important part of the complex natural system that breaks down dead plant and animal parts into more simple compounds.

Mushrooms appear only when conditions are right for the production of these spore producing structures. For a particular fungus to go into this reproductive stage it must be mature enough and the temperature and moisture conditions must be right. Most prefer high levels of moisture and warm temperatures, while some species fruit during cool periods.

It’s interesting that when we see these sometimes large structures, we are only seeing a small part of the fungus. The remainder is below the surface in a string-like form. Mushrooms are actually made up of a compacted mass of these strands.

Though an occasional mushroom appearance in the yard is normal, there are two conditions that result in frequent complaints from homeowners. These saprophytes often proliferate soon after clearing for new home construction. Tree and shrub roots are invariably left below the soil surface, and this fresh, dead material provides a buffet for these fungi. Unless the debris is dug up and removed, high numbers of mushrooms will be seen sporadically for several years, until this buried woody material is decomposed.

A second condition results in some of the more intriguing and sometimes objectionable mushrooms. Landscape beds that are heavily mulched with fresh wood chips provide an environment that is ideal for some of the foul smelling and strange looking species. Stinkhorn mushrooms usually receive the most attention because they emit the odor of rotten meat. This is a mechanism that is used for spreading spores by flies and other insects that are attracted.

One of the most interesting requests of my career involved the identification of one of these fungal species. The caller, from Gulf Breeze – of course, described them as possible “UFO Eggs.” Upon arrival, I found a landscape bed containing dozens of round, white, ball shaped structures ranging from 2 to 4 inches in diameter. Some had broken open at the top and scarlet tentacle-like structures were protruding. This was one of the puff ball species of fungus that was feeding and reproducing on a thick layer of fresh wood chips.

As frequent rains return, we will be seeing more mushrooms of various sizes and shapes. With only a few exceptions, they do not cause diseases of landscape plants. Some are poisonous if ingested. There is no environmentally safe fungicide that can be recommended for control. Gardeners should accept and appreciate this special group of fungi. In cases where the mushrooms are objectionable they can be removed, mowed down or golfers can use them for practicing tee shots.