What Are Stinkhorns: Tips For Removing Stinkhorn Fungi

What Are Stinkhorns: Tips For Removing Stinkhorn Fungi

By: Jackie Carroll

What is that smell? And what are those odd-looking red-orange things in the garden? If it smells like putrid rotting meat, you’re probably dealing with stinkhorn mushrooms. There is no quick fix for the problem, but read on to find out about a few control measures you can try.

What are Stinkhorns?

Stinkhorn fungi are smelly, reddish orange mushrooms that may resemble a wiffle ball, an octopus or a straight stem up to 8 inches (20 cm.) high. They don’t harm plants or cause disease. In fact, plants benefit from the presence of stinkhorn mushrooms because they break down rotting material into a form plants can use for nourishment. If it weren’t for their horrible smell, gardeners would welcome their brief visit in the garden.

Stinkhorns emit their odor to attract flies. The fruiting bodies emerge from the egg sac covered with slimy, olive green coating, which contains the spores. The flies eat the spores and then distribute them over a wide area.

How to Get Rid of Stinkhorn Mushrooms

Stinkhorn fungus is seasonal and doesn’t last very long. Given time the mushrooms will simply go away on their own, but many people find them so offensive that they aren’t willing to wait. There are no chemicals or sprays that are effective at removing stinkhorn fungi. Once they appear, about the only thing you can do is close the windows and wait. There are, however, a few control measures that can help keep them from coming back.

Stinkhorn mushrooms grow on rotting organic matter. Remove underground stumps, dead roots and sawdust left from grinding stumps. The fungus also grows on decomposing hardwood mulch, so replace old hardwood mulch with pine needles, straw or chopped leaves. You might also consider using live ground covers instead of mulch.

Stinkhorn fungus begins life as an underground, egg-shaped structure about the size of a golf ball. Dig up the eggs before they have a chance to produce fruiting bodies, which are the above ground part of the fungus. In many areas, they’ll come back a couple of times a year unless you remove their food source, so mark the spot.

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Stinkhorn Fungus Control - How To Get Rid Of Stinkhorn Mushrooms - garden

Q: A mulched area under one of my trees has a large number of stinkhorns in it. It is beside my children’s bedroom windows and it certainly has the correct name of “stink”! Is there any way to kill them and prevent them from coming back?

A: There are four common stinkhorn mushrooms I’m aware of.

Common stinkhorn, Phallus impudicus, has a white shaft and a brownish-green “head”

Elegant stinkhorn, Mutinus elegans, (and also M. caninus and M. ravenelii), has a orange-pink shaft and a dark, tapered head.

Latticed stinkhorn, Clathrus ruber, is orange pink and looks like a red bell pepper turned inside out.

Stinky squid mushroom, Pseudocolus fusiformis, looks like a pink squid.

As their name implies, they all stink to high heaven.

They grow in damp wood mulch, emerging from a whitish, semi-solid “egg”. Once they take on their final shape, their spore sacs emit a green slime that attracts flies and beetles to the area. The insects feed on the mushroom and carry the spores wherever they land.

Since the fungi depend on warm, damp mulch, the easiest way to control them would be to loosen the area with a rake and halt any nearby irrigation.

elegant stinkhorn

elegant stinkhorn

netted stinkhorn

dog stinkhorn

latticed stinkhorn

stinky squid mushroom

What causes stinkhorn fungus?

stinkhorns are known to be a noxious fungus, and their smell can be likened to that of feces or a dead and decaying animal. Although the stinkhorns may smell offensive, they are not poisonous to humans or pets. Stinkhorn fungi will not harm your pets or any other plants in their vicinity.

Subsequently, question is, how do you kill fungus in mulch? Spraying bleach on the mulch can kill the fungus without harming plants if used correctly. In fact, a diluted bleach solution is sometimes used to sterilize and sanitize plant cuttings and growing mediums. Spray the fungus in the mulch with a solution of 1 part bleach and 9 parts water.

Also asked, how do I get rid of stinkhorn fungus on my dog?

There's not much you can do to rid yourself of the stinkhorn in the mulch bed. You might try raking the mulch to break off the stalk and shorten its life cycle. Stinkhorns tend to appear more frequently in hardwood mulches than in pine bark mulch. Fungus grows on mulch occasionally as part of the natural decay process.

What do Stinkhorns smell like?

All stinkhorns produce foul odors, which some people describe as a putrid, rotting meat smell. The smell attracts ants and flies that then pick up and carry the mushroom spores to other places.

How to Get Rid of Octopus Stinkhorns

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Bright orange, with a sculptural shape and a smell that could stop traffic -- though not in a good way -- the octopus stinkhorn (Clathrus archeri) is an unwelcome ornament in the garden. The spores of the fungus, a native of Australia, are usually carried into U.S. gardens on wood mulch or imported plants. The eight-armed fruiting body emerges from egglike structures when conditions are warm and moist, then dry. The bright arms develop a brown or black goo filled with more spores the goo causes the rotten stench and attracts insects to spread the next generation. There is no chemical control, so get out your shovel to eliminate octopus stinkhorns.

Put on glove to avoid getting spores or the smelly goo on your hands.

Kick over the eggshaped white structures before the stinkhorns emerge and pick them up with your hands, or dig up the open octopus stinkhorns with a shovel.

Put the octopus stinkhorns in a sealable plastic bag and dispose of them in the trash.

Remove the stinkhorns each time they reappear during the season. They may not appear in the same place again, and the threadlike mycelium that they grow from is usually so widespread in the mulch that you would have to remove all of it down to the ground to ensure the fungi are gone for good.

Replace your hardwood mulch with pine bark, pine straw or a living ground cover to decrease the amount of decomposing wood -- the fungi's favorite food -- in your landscape. This does not guarantee stinkhorns will not reappear if the mycelium is present in your soil.

Michelle Keller-Pearson, UW-Madison Plant Pathology

What are stinkhorns? Stinkhorns are mushrooms that are found from the tropics to more temperate regions such as Wisconsin. They can suddenly appear in mulch, lawns, and areas with bare soil. These visually-shocking fungi get their common name from their characteristic, unpleasant odor. Although they are often unwanted additions to home gardens, stinkhorns do not cause plant disease. Because stinkhorns can grow on dead organic material, they actually are beneficial in that they contribute to the recycling of plant debris into nutrients that improve soil fertility and can be used by garden plants.

What do stinkhorns look like? Stinkhorns grow into various shapes, but they are best known for looking like horns or penises. A few species grow several appendages, resulting in an octopus-like appearance. Some species have a veil attached below the cap that resembles a lacey skirt flowing from the mushroom’s hollow stalk. Stinkhorns can range in color from white, beige, and olive to bright orange or red with black accents. The tips of mature stinkhorns are usually coated in a spore-containing slime. Gardeners often discover immature stinkhorns as they dig in the soil. The immature forms appear as whitish to pink or purple, egg-shaped masses. Stinkhorns develop rapidly sometimes growing up to four to six inches per hour, and can generate enough force to break through asphalt.

Where do stinkhorns come from? Stinkhorns are often first introduced into a garden in organic materials (e.g., soils and mulches) that contain microscopic hyphae (i.e., fungal threads) of stinkhorn fungi. Once stinkhorns mature, they produce a pungent, off-putting odor that is reminiscent of rotting flesh or dung. This smell may disgust people, but it attracts insects, particularly flies. Flies and other insects eat the slimy material at the tips of stinkhorns and carry spores in this slime to new locations as they move around in the environment. In many ways, this process is comparable to the distribution of pollen by bees (but of course without the more appealing scents associated with most flowers).

How do I control stinkhorns? Stinkhorns are short-lived and will naturally disappear quite rapidly. If stinkhorns are too unsightly, if their smell becomes too putrid, if they attract too many insects, or if there is concern about small children or pets eating them, pluck them from the ground and discard them as they appear. Keep in mind however, that removing stinkhorns will not eradicate them. Stinkhorn hyphae will remain in the soil or mulch and will eventually produce other stinkhorn mushrooms. In addition, flies and other insects carrying stinkhorn spores can introduce these fungi to new locations.

Naptime DIY: Kill stinkhorn mushrooms

If you garden or have mulch on your property you’ll eventually have mushrooms. In some cases, if you’re unlucky you’ll have stinkhorn mushrooms. The stinkhorn mushroom is such a vile, malodorous thing that if Thoreau had seen them on a walk he would’ve cursed nature and insisted that it be paved over with concrete.

The stinkhorn mushroom is accurately named. They’re quite easy to recognize because they’re more phallic than most mushrooms, stink and attract flies. To the untrained eye it looks like a penis coming up from the ground. Insects land on the smelly phallic mushroom, fly off and then create other areas of stinkhorn mushrooms.

How to describe the smell? At first it smells like a flower, you then realize that it actually smells like rotten meat. What’s worse is that the smell permeates your senses. Hours after digging up a handful of them I still had residual smell inside my nostrils. I’ve never vomited while gardening, and I can take some disgusting smells, but the stinkhorn mushroom made me gag in the garden.

I’ve seen some folks say that mushrooms are the sign of a happy lawn or garden. The stinkhorn mushroom and the amazing smell that it produces, easily counteract any positive mojo that your garden has from producing mushrooms. Unless you want to smell like Lady Gaga wearing her meat dress after a month on tour, you will want to remove these evil things ASAP.

Mushrooms grow in moist areas. The stinkhorn mushroom is attracted to places where there is mulch. Mushrooms also grow where your PH is higher than it should be.

  1. Dig up the stinkhorn mushroom from its egg shaped base.
  2. Place the mushrooms in a sealable bag
  3. Dig up the mulch/soil around where it was.
  4. Spread lime around the area.
  5. For additional security I would dilute bleach with hot water and spray it on the infected areas.

We tried steps 1-4 and four days later we had a couple of stinkhorns greeting us with a foul odor. While it would’ve been great to get rid of them organically, it just didn’t work for us.

  • Read the directions on the lime. It may say to wet the soil before or after you spread the lime down.
  • After you dig up the stinkhorns spray bug killer around the area. This will kill the flies or other creatures that might try to spread the spores.
  • Remove some of the mulch and agitate the area with a shovel or hoe. At the base of each of those eggs shaped bases is a series of skinny purple roots. Leave the mulch away from the area for a while to let it fully dry out.

As a stay at home dad I miss having the spare time to fix things. Even though the child is my full time job, things still break or need a fix in the house. Sometimes the repair will be something that I can easily complete and other times it’s a repair that I simply should’ve paid to have it done. Regardless, I’ll write it up here in hopes that you may be able to gauge what you can do and when you need to call in for help. The series is called, Naptime DIY because the tasks are hopefully accomplished in 60 minutes, which is a good naptime period.

Watch the video: Most Bizarre Plants and Weirdest Fungi