Chocolate Tube Slime

Chocolate tube slime sounded so strange that I had to learn more about it.

Chocolate tube slime on tomato leaf and planter. Photo courtesy of u/Lilac_Fumes_

Like our beloved dog vomit slime mold, chocolate tube slime molds were once classified as a type of fungus. Scientists now include this family in the protists. Amoebas are another type of protist.

Slime molds have the bizarre ability to move across materials in their search for food. They do this so efficiently that city planners now use some slime molds to design roads and electrical grid systems. Normally found as individual cells, chocolate tube slimes, also known as pipe cleaner slimes and tree hair, converge into giant communities.

Chocolate tube slime (Stemonitis splendens) looks a lot like a sea urchin and is usually found on forest floors feeding on decaying material. They are sometimes found attached to older wooden houses. Chocolate tube slime mold also grows on planter pots but what I find particularly strange is that they can even grow on plants that are alive and green. I recently heard of chocolate tube slime growing on tomato stems. The tomatoes looked fine, they just had little brown tufts growing on them.

Chocolate tube slime (Jason Hollinger) CC BY 2.0

The sea urchin-like spikes are fruiting reproductive bodies. Fungal spores are released from these tubes. Before they reach the stage, they start as white spikes that are often topped with pink globs of I don’t know what. Those white spikes turn a golden yellow and the globs turn golden yellow. Eventually, these spikes turn chocolate brown. Sometimes they turn a reddish-brown. They can be ½” to ¾” tall or huge.

Since chocolate tube slime molds feed on decaying organic matter, they will not harm your tomatoes or other garden plants.

Have you ever seen chocolate tube slime mold in your garden?