Monday, August 23, 2010
Late summer heat encourages the flowering of large and colorful blobs on the bark mulch surfaces of neighbourhood playgrounds. Had these playgrounds still possessed the nausea-inducing spinning apparati of decades past, or were there crumpled beer cans scattered about--tell-tale signs of underage binge-drinking--one might mistakenly assume vomit.
No. Slime mold!
The affinities and taxonomies of this nominal group are complicated and not well understood. However, it seems that the ones that make pretty-coloured splatter pies on bark mulch can be identified as members of the Phylum Mycetozoa, Class Myxogastria, which includes five orders, one of which is the Physarales, which includes the genus Fuligo, a well-known denizen of bark mulch.
It has a fascinating life cycle, which you can read about here. The important thing to know, playground-wise, is that for part of the year it exists as a multinucleate amoeboid thing that squilches through the bark mulch beneath the sneakered feet of children. When the children are away on summer vacation and the diminishing moisture content of the bark mulch reaches a level unbearable to the amoeboid entity, it rises to the surface and forms a sporulating blob that looks remarkably vomit-like. It can be one of several colours, usually in the white-yellow-orange range. It eventually dries to a dusty brown or black crust.
In one of the parks of this city, you can even find red ones. I have not been able to find other images of this form.