The Dog Vomit Fungus is not a fungus, but a slime mold. I guess calling it the "Dog Vomit Slime Mold" wasn't very appealing to the International Association of Slime Mold Naming Scientists (IASMNS). Anyway, its scientific name is Fuligo septica. Which, when roughly translated into english means, "sticky stuff on the bottom of Bob's shoe".
In central Pennsylvania, the Dog Vomit Fungus usually appears on newly spread mulch in late spring or summer following soaking rains. During the spring and summer months, numerous sightings are reported almost every year. The slime mold is usually found growing in areas near homes and office buildings, but can appear in forested areas as well.
The color of this wonderful mold is often bright yellow, and in some instances, sickly orange. This colorful growth occurs when the mold is beginning its fruiting stage. It can appear seemily overnight causing some people to question what it is and how it got there. Therefore, you can see how this mold got its common name........
It must be Fluffy from across the street.......
The size of this species can be very small (say a Jack Russell terrier who ran in circles too much) to very large (that Saint Bernard ate my burrito).
The next stage in the life of this slime mold is quite depressing. Like many humans, the mold matures into a harder, larger mass that loses much of its bright attractive color. Although still able to project fear in some people at this stage, it becomes much harder to notice.
During the next stage the slime mold becomes crusty and un-inviting.
Brave souls can pull back the outer layer of the mold to reveal an even darker brown mass hiding inside.
The final notable stage is the "spore" stage. This is the time during life cycle of the mold when millions of spores are released by rain, wildlife, unsuspecting children and in this case, my wife.
Control measures: None Required. This species is relatively harmless to plants and animals.
Some people, not to be named, enjoy placing "young" slime molds in neighbors yards or sidewalks. But, be warned, the molds are quite slippery when in their colorful stage.