[parkmaster]

Here is a close up view.

 

[bob]

I believe the knickname is "dog vomit" fungus.

 

[Enviro Green]

That is a slime mold. It is a fungus, and typically manifests itself during wet weather. There is no good cure I know of, just remove the mulch from the area and see if you can reduce the moisture, less irrigation, etc.

Preventive chemical treatments tried over the years have been found ineffective. Slime molds get their nutrients from dead organic matter, such as mulch. Although slime molds may grow on plants, they do not harm plants. Slime molds will eventually disappear on their own. If you want to speed this process, rake the mulch to promote air drying.

Also, use a high pressure stream of water, hose, etc to remove the slime mold and it will help for a bit.

Best luck,

EG

 

[turfsurfer]

This does indeed look like what is nicknamed "dog vomit fungus" around here. It will start out yellow and turn to a sickly orangish color before turning dark and powdery as it dries up. It will not harm the plants it grows on, but it is one of the reasons I am seriously considering getting out of doing any more hardwood mulch installations in the future. Sick and tired of installing awesome looking fresh mulch and having this stuff sprout all over it throughout the season. Have tried several different vendors and grades of hardwood and have so far not found one resistant to it. Too bad I personally don't prefer Cypress mulch as I have not seen this fungus growing on it, just the hardwood.

 

[GroundKprs]

Don't look for control or immunity. Slime molds grow basically on decaying wood, so if you use woody mulch of any kind, you're gonna get slime molds. If you want a document to back up this idea with clients, check http://www.colostate.edu/Depts/CoopExt/TRA/PLANTS/slime.html Or your own state extension may have a similar document.

Control is mechanical: just scrape and lift out with a shovel, or break it up with a rake.