Dog Vomit Slime Mold – those are four words that command attention.
And when you spy this bright yellow primitive organism in your newly landscaped yard, you will not have any trouble identifying it.
Imagine what happens if your dog climbs up on the kitchen counter and scarfs down a carton of eggs. Bright yellow, slimy, completely revolting goo out in the yard … Yup, that’s Dog Vomit Slime Mold.
But don’t blame Rover too quickly – this ancient organism has been around long before there were dogs. Through DNA analysis, scientists have determined that slime molds were one of the first living organisms to move onto land hundreds of millions of years before there were plants or animals on Earth.
Evolutionary biologist Sandra Baldauf told The New York Times “they may be as old as the terrestrial ecosystem.”
We’re talking a billion years or so. Old.
Today, scientists have identified about 900 species of slime molds around the globe.
Dog Vomit Slime Mold was first identified in 1727. Carl Linnaeus, the originator of the scientific naming system, called it Mucor septicus in 1763. It received its current scientific name, Fuligo septicus, in 1780, which is a nice enough moniker but not nearly as punchy as Dog Vomit Slime Mold.
This slime mold is native to temperate lands around the world, from North America, Europe and Russia in the northern hemisphere to Australia, New Zealand, southern Africa and South America in the southern hemisphere.
The reason Lake Martin residents are likely to spot it is that Dog Vomit Slime Mold is commonly found in moist, shady areas with lots of organic matter, such as wood and leaves. That’s a pretty good description of the fresh mulch used in irrigated flowerbeds around landscaped lake houses.
Although it is sometimes referred to as a fungus, Dog Vomit Slime Mold is actually a member of the Protoctista kingdom that includes all manner of primitive life forms, including amoebas, kelp and red algae.
This fascinating species changes shape, form and maybe even location overnight. It often emerges on or near ground level as a slimy transparent “plasmodium” that looks something like a blob of egg whites on warm, moist nights – a condition that pretty much sums up nights on Lake Martin from now until September or so.
The plasmodium has the ability to “crawl” like an amoeba, as the cells multiply and the colony grows.
When conditions begin to dry – sometime after the 3 a.m. sprinkler system shuts off or after a rain – the plasmodium “fruits” and begins to look more like a bowl of uncooked, beaten eggs before it grows bright yellow structures that look something like corals or a group of thousands of very tiny antlers or a foamy blob. It is often seen in the fruiting stage early in the morning. As the sun hits this structure and temperatures begin to rise, Dog Vomit Slime Mold will dry and harden, taking on the look of yellow, orange or whitish foam insulation. On its surface, you may see drops of dark orange or red liquid, which may look like drops of blood (they’re not). This transformation occurs very quickly, in a matter of hours.
As it continues to dry out, the hardened blob will begin to lose its color and become crusty. But it’s not dead. Instead, beneath the surface, this organism is developing millions of spores that are released when the crusty surface is stepped on by animals or broken open by wind or rain. If you break one open and see what looks like a puff of smoke, it’s a spore cloud that spreads this organism at the whim of the winds.
These spores will land, and if they wind up on decaying wood or other organic matter, the process will begin again when the moisture and temperature are right.
Slime mold spores can lay dormant for years waiting for the right conditions.
Dog Vomit Slime Mold is not harmful to most people, though it can sometimes cause asthma flare-ups or allergic reactions similar to hay fever.
One unique characteristic of this slime mold is that it is highly resistant to toxic metals, especially zinc, allowing it to survive in places where not much else can.
Throughout history, this organism’s almost magical appearance and rapidly changing character has at times caused a folklore stir.
Scandinavians once thought it was the vomit of troll cats, mythical animals that were conjured up by witches to suck milk from cows and steal cream from farmhouses. The Dutch sometimes call it witches’ butter.
And remember those eggs on the counter? Sometimes here in America it is called scrambled egg slime mold, which is an appropriate name if you happen to be a very early riser.
Some information for this article came from the Master Gardener Program at the University of Wisconsin, iNaturalist, Wikipedia and The New York Times.