Slime mold. It sounds like something on an unwashed ghostbusters uniform. Slime molds don’t always look slimy or moldy though.  It depends on what kind they are. One thing all the slime molds have in common is that they thrive in moist environments. This year, Connecticut has experienced frequent and abundant rainfall so the slime molds are popping up in landscapes and gardens.  I’ve heard about a bright pink one on mulch but haven’t seen it so here’s a pic from the internet. From:

So what is a slime mold?  For quite a long time, they were classified with the fungi. They’re not closely related to the fungi, though, and are now classed in the kingdom Protista. There are a few different kinds of unrelated organisms commonly called slime molds.  Some are composed of only a single cell while others are multicellular. They are able to produce spores that allow for dispersal and survival of unfavorable conditions. They feed on dead organic matter (helping out with decomposition) or sometimes yeast, bacteria, or fungi.

When conditions are right, many slime mold cells may congregate together, forming visible growths on surfaces of plants, decaying logs, or soil surfaces.  A few interesting examples of slime molds have come across my desk this season and here they are:

Yellow or white slime mold can appear in a very short time on the blades of turfgrasses. If you’re unfamiliar with this, it can look like a dreadful disease with the potential to wipe out your lawn.  In fact, once the surface dries out, spores in the masses will be dispersed and there will be no remaining evidence of the slime mold. No harm done.

The common fungus that grows on bark mulch and is aptly named ‘dog vomit slime mold’ or ‘dog vomit fungus’ (Fuligo septica). This type of slime mold, even though it’s pretty large, is only a single cell with many nuclei.  When it pops up in gardens on mulch, it does look pretty disgusting and many inquiries are about how to get rid of it. You can’t. It’s in the soil below the mulch as well is in it.  But, you can remove the unsightly growth when it appears.  It is not harmful to plants.  More info on this slime mold can be found at  Photo below from: By Siga – Own work, Public Domain,

And, finally, the most interesting slime mold of the season so far: chocolate tube slime mold (Stemonitis sp.). This perfectly named slime mold was found growing on an old section of a pine trunk being used to support a planter.  Enjoy, then go get yourself some chocolate since it’s now on your mind! UConn photos.

By J. Allen