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While most gardens will appreciate the extra water that comes with rainy weather, an very moist season creates the perfect conditions for a fungi.

Not all fungi are harmful to plants, other than what humans may consider a few cosmetic blemishes. In fact, some fungi are very beneficial to plants and play a vital role in ecosystems.

Justine Kandra, a horticulturist with the Kemper Center for Home Gardening, shares 5 fairly innocuous and fascinating fungi found in home gardens.

1. Corn Smut Fungi

Also known as “boil smut”, corn smut fungus can affect all types of corn, including popping and sweet corn.

The large, dramatic, white to gray-silver masses containing black teliospores can form on any part of the corn plant. This includes stalks, tassels, and ears. Teliospores are a type of fungal spore that have thick walls and can withstand cold temperatures and overwinter, ready to germinate in spring and infect new corn plants.

We do not recommend using fungicides to control corn smut, but crop rotation and planting resistant varieties can reduce infection. But the immature fungal masses are edible and even considered a delicacy in Mexico.

2. Cedar apple rust

This fungus requires two unrelated host plants to complete its life cycle: a juniper (usually Juniperus virginiana or eastern red cedar) and an apple or crabapple.

On the juniper, the fungus forms a brown gall up to 2 inches wide on twigs. In spring, during rainy weather, the galls swell and produce bright orange, gelatinous structures called telial horns, which release spores. The spores then infect a susceptible apple or crabapple. This causes circular, yellow lesions to appear on the upper surface of the leaves.

In late summer, small, raised bumps will appear on the undersides of the leaves below the yellow spots. The bumps release spores that infect junipers, completing the life cycle.

3. the Mycorrhizal network

The soil beneath our feet is home to a complex web of connections between animals, plants, fungi, and microbes. Researchers are just beginning to understand these interconnections, which is why soil is often described as a “black box”.

But what we do know is absolutely amazing: diverse ecosystems of plants above ground are supported by equally diverse underground populations of mycorrhizal fungi, or specialized fungi that form a symbiotic relationship with plant roots.

The fungi benefit from the plants by consuming some of the sugars they produce, and the plants benefit from the fungi by giving them access to more water and nutrients. Researches estimate that over 80% of all plant species have a relationship with mycorrhizal fungi.

4. Fungi Fairy Rings

Mysterious and ephemeral, circular rings of mushrooms called fairy rings can appear overnight in lawn areas and seemingly disappear just as quickly.

These mushrooms are simply the above-ground, reproductive structure of any number of saprophytic fungi, or fungi that feed on decaying organic matter. The organic matter fairy rings break down is often old tree stumps, roots, logs, lumber, and other larger pieces of organic material in the soil below the lawn.

The rings can be as small as two feet wide or reach upwards of 15 feet wide.

We usually do not recommend treating for fairy rings since the fungi do not typically cause direct harm to the lawn. Fairy rings will disappear on their own over time, but the mushrooms can easily be raked up and removed if there is a chance that a curious pet or child might eat one.

5. Stinkhorn mushrooms

Stinkhorn mushrooms get their name from their foul-smelling fruiting structures that rise out of mulched garden areas or lawns.

Unlike most mushrooms, stinkhorns do not release airborne spores and rely primarily on insects such as flies to spread their spores. Flies are attracted to the mushroom, landing on the sticky spore mass called the gleba located at the tip of the fruiting body.

Even stranger than the stinky fruiting structure is the immature stinkhorn in its underground “egg” stage. Although alarming in appearance, stinkhorns are harmless to plants and feed off decaying organic matter.