Hi Raina,

The picture shows this to be growing in bark mulch which by appearance and growing conditions appears to be Dog vomit slime mold (Fuligo septica). It is often found on bark mulch in urban areas after heavy rain or excessive watering. Their spores are produced on or in aerial sporangia and are spread by wind. You will most often find dog vomit slime mold in moist, shady areas and on materials such as mulch, rotting logs, leaf litter, and untreated lumber. It is also known by another nickname—scrambled egg slime mold—because the fruiting body (the part you see) is light-yellowish in color and looks a bit like scrambled egg curds. Dog vomit and other slime molds are saprophytic, which means that they feed on decaying organic materials. They are not diseases and won't harm your plants. It is most likely to show up during warm, wet periods and sometimes seems to pop up out of nowhere overnight. The good news is that it is harmless, but it's challenging to prevent it, as the spores spread easily and can survive for years.

https://mastergardener.extension.wisc.edu/files/2015/12/DogVomitSlimeMold.pdf

It usually forms on mulch in late spring to early summer following extended periods of rain. Initially, it begins as a bright yellow, gelatinous growth, emanating from spores that were in the mulch. As it matures, it hardens, fades in color and becomes less noticeable. Finally, it dries out completely and decomposes, but leaves behind millions of spores that can be carried away on the wind.

We had a very wet spring which has led to favorable conditions for slime molds and having bark mulch in a shady area is the perfect environment for this to occur. Also consider how you are watering the area around the front porch. Here is a handout on watering efficiently: https://cmg.extension.colostate.edu/Gardennotes/267.pdf

Changing the environment will lessen all the fungal growth on any type of mulch. Keep the mulch dry. In rainy times, stir up the mulch with a rake to break up any colonies of fungus. This will also fluff up and dry out the mulch making it less hospitable for fungal growth.

There is no control for dog vomit slime mold and it does not really need to be controlled. It usually goes away on its own in a couple of weeks. if you dislike the look of dog vomit slime mold you can use a shovel to scoop up the slime mold and the top layer of the mulch that's feeding it, and dispose of it. If dog vomit slime mold continues to be a problem, consider switching from wood-based mulches to inorganic mulch, like gravel. Hope this helps.

Thanks for contacting Ask Extension.

NancyO