Fungus in the Garden Soil

How Fungus Grows

• Mature fungi often produce fruiting bodies, such as mushrooms, that extend above the ground to release spores. These spores then carry on the wind, germinate in the soil and then grow into filaments -- or thin, hollow thread-like structures called hyphae that cannot be seen without magnification. Hyphae expand quickly; according to scientists from Palomar College, if humans could place all the hyphae produced in one day by one soil fungus end to end, the line would extend nearly a mile. Once these hyphae become an intertwined mass, they are known as mycelium. Soil fungi, such as mycorrhizae, often attach to root structures of plants.

Benefits of Soil Fungi

• Most soil fungi are beneficial. They contribute to soil structure, reduce erosion and help plants uptake nutrients and water. Some plants could not grow without a group of soil fungi known as mycorrhizae. Ectomycorrhizae, for example, is a type of mycorrhizae fungus that surrounds the root tips of trees to form a symbiotic relationship. These fungi help the trees absorb water and minerals that would have leeched through to lower layers of the soil . In turn, the trees provide the fungi with carbohydrates it produces specifically for that purpose. Scientists still do not fully understand the complicated dynamics of this relationship but believe many coniferous species could not thrive without it. These soil fungi sometimes produce mushrooms or other fruiting bodies at the base of the trees they inhabit.

Nuisance Fungi

• While most fungi are not harmful to garden plants, some are nuisances. Check the lawn for bothersome mushrooms that might spread to the garden. Inky caps, for example, are common lawn mushrooms that decompose quickly into a puddle of dark liquid. Stinkhorns look like giant fingers protruding from the grass and produce an offensively odorous slime that attracts insects. Stinkhorns, in particular, are not welcome in gardens for their ability to attract pests.

What To Do With Nuisance Fungi

• Check your lawn for mushrooms and other fruiting bodies of fungi before establishing your garden bed. Then plant that bed as far away from these patches as possible and dig out the fruiting bodies before they fully mature. Also make sure the soil is properly drained and there is no organic debris, like wood scraps, laying around. Fungi feed on organic material. These steps will help reduce the chances nuisance fungal spores will migrate to the garden soil. Attempting to dig up the lawn soil in which the patches live is virtually pointless; fungus is present in all soil, most do more good than harm and by the time you see fruiting bodies, the mycelium is fully integrated.