Unsightly but Beneficial

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Fungi represent the largest category of plant pathogens in our lawns, landscapes and gardens, and fungi also account for the largest number of bizarre and frequently alarming “growths” spotted on residential properties. The latter would include the stinky squid mushroom (Pseudocolus fusiformis), recently reported in a landscape in Columbus County.

The stinky squid fungus is considered beneficial, as is the case with fungi in general. Fungi are extremely important in the decomposition of dead plants and animals, the cycling of nutrients in landscapes or the forest, and the uptake of plant nutrients in mychorrhizal associations with plant roots.

However, the stinky squid mushroom would be considered unwelcome by many homeowners, given the strange appearance, and the unpleasant odor that it shares with other members of the stinkhorn family (Phallaceae). In this case, it’s important to remember what mushrooms represent, and what our limitations are in actually doing anything about them.

Mushrooms are reproductive structures, and individual mushrooms don’t tend to persist for very long. Fungicide applications won’t provide control of the mushrooms unless the fungicide is specific for the fungal species in question (unlikely), and the fungicide is applied in an adequate dose and volume of water to actually kill the fungal hyphae growing in the ground or the mulch layer (extremely unlikely).

One response would be physical control, such as hand removal or raking the structures under the mulch layer with a garden rake. In addition, remember that wood-based mulch is a much better food source than pine straw for the various beneficial fungi that we encounter. If mushrooms and mushroom-like structures in the landscape are a problem for you, consider using less wood-based mulch and more pine straw; or consider frequent raking and disturbing of wood-based mulch beds.

If you have pets, be aware that mushroom poisonings do occur, and dogs or other pets can become seriously ill or die as a result. In a 2018 interview with Raleigh’s News and Observer, Dr. David Dorman of the NC State University College of Veterinary Medicine stated that about one-third of the mushrooms found in our state can be toxic.

As noted, mushrooms can come and go quickly, and we can’t eliminate the possibility that our pets might encounter and eat something deadly. Nevertheless, Dorman recommends that pet owners keep an eye on their property, and remove mushrooms as they occur. Remove the entire mushroom, including the base out of the ground. The use of gloves will protect your skin from potential contact with toxins.

Image of squid fungus

Reproductive structure of the stinky squid fungus (Pseudocolus fusiformis). Image provided by Dalton Dockery/NC State University; ID by Bill Cline/NC State University.