Monday, July 12, 2010

Slime Molds

I found a decomposing log that was hosting a wonderful collection of slime molds. These are the spore producing structures of the Chocolate Tube Slime Mold, Stemonitis splendens.

At certain stages in their development, slime molds become mobile and can become real travelers. As a mass of protoplasm held together by an enveloping membrane, they travel in a way similar to an amoeba or The Blob. I’m referring to the original Blob with Steve McQueen and not any of the subsequent incarnations. The whitish patch in this photo is the body of the mold as it prepares to develop the spore producing tubes.

The base of each narrow spore capsule is anchored in a common base produced by the mold. The strands don’t always stick together as this bunch has. Most often they act individually and create a more disorganized collection.

A little farther down the same log, I found this lovely Scrambled-egg Slime Mold, Fuligo septica, sometimes unkindly referred to as the Dog Vomit Slime Mold. This is probably the most commonly seen slime mold. Most people are introduced to it when they find it growing in newly spread landscaping mulch. I more enjoy finding it out in the woods where it belongs.

As it ages, it darkens and oozes a reddish liquid. I can see why it troubles some people when they see it beside their home.

It looks as though some more species of slimes may inhabit this log, but they are not in an easily identifiable stage. Slime molds go through many changes as they develop. When moistened, spores develop into microscopic organisms that travel along thin water films. Those organisms eventually join to form a larger entity that continues to grow. Throughout these stages, the primary food source is bacteria. It’s not until environmental conditions become unfavorable that the slime mold shifts into spore production mode.


  1. My goodness, I never realized slime and mold could be so fascinating! Fantastic post!

  2. Oh, people who are troubled by slime molds are just citified sissies.

    I love the Chocolate Tubes! Your photos are far superior to those in my field guides. So glad you found them when you did!

  3. Steve, I get pretty excited when I come across slime molds, but if I were to find this chocolate tube slime mold, I'd be jumping up and down!! I hope you don't mind that I sent copies of the 2 pictures to my little sister, my mentor in all things slimey!! ~karen

  4. Wow....I am real thrilled that you had to say the think travels...and you had to relate it to the ""blob" of all will I ever sleep!!! ; }
    All kidding aside the Chocolate Tube is amazing and beautiful!! Your photos really show good details...Some I have seen but never paid much attention...I guess if we don't get rid of this hummidity I may be a little moldy...and slimey!!!

  5. Thanks, Lois. I try hard to show slime in a positive light.

    Thanks, Jain. I was actually looking for something else and almost ran my face into these before I saw them.

    Karen - I certainly don't want to stand in the way of a little slime sharing between sisters.

    grammie g - Unlike the typical space visitor, terrestrial slime molds seldom travel more than a few feet a day. I think you'll have time to get out of the way if one charges.