Botany Photo of the Day

Fantastic, I love pictures of slime mold. Thanks, it's fascinating!

any way to cultivate slime molds? or just a hit and miss function? what can I do to encourage slime molds to grow in a specific place?

I'd definitely be a little worried if I found that growing anywhere in my garden!

Beautiful. I love slime moulds & would happily give these a home...I'm interested in any replies to David Bond's questions. I've tried without success.

Most references I can find regarding cultivation of slime molds refer to growing them in the lab on agar for study. That being said, it might be possible to culture them in a lab then release spores in the wild to see if anything will take, but I've no idea.

One reference I did find suggested the use of rolled oats as opposed to agar. If you have access to it (it might be subscriber-only), here's the 1936 paper: A Method of Cultivating Myxomycete Plasmodia, by W.G. Camp in the Bulletin of the Torrey Botanical Club.

David and Ingrid, I emailed Dr. Harold Keller with your questions. He very kindly replied:

“Hello Daniel

Okay, here goes!! Usually I will not identify a myxomycete species without microscopic examination but the image here I am fairly certain is Stemonitis axifera the same species that our slugs fed on the surface of an old decayed oak log. If I understand you correctly you want to know how to cultivate slime molds in an outdoor garden. I would say your best bet is to use oat or wheat straw as mulching and water (either rain or by hose) to keep the mulching wet over long period of time. The mulching should be thick enough to cover the ground. You can use bark mulching around trees and myxomycete species will develop, usually Fuligo septica. Sometimes Physarum cinereum will grow in lawns (we have it on our Saint Augustine grass) especially when the thatch builds up after letting the clippings accumulate.

A natural place to look (not in a garden) is a flower bed that has irises, lilies, etc. and plants that have a basal rosette of leaves that eventually die and form ground cover that looks messy but is ideal habitat for Myxomycetes. Most gardeners want to remove those dead leaves to keep the flower patch neat, clean, and more presentable to the public. But if you want myxomycetes let the dead leaves accumulate. There are actually some very rare myxomycetes that develop in flower beds with a lot of dead basal leaves. This creates a habitat that functions like mulching one would add to a garden. The same is true of shrubbery or bushes (lets say a rose bush) where the leaves accumulate under the bush myxomycetes will form fruiting bodies following rainy weather over several days.

This is a long winded answer but should give your readers a better idea how to cultivate myxomycetes in outdoor habitats. Myxomycetes are not pathogens but can form large numbers of fruiting bodies on grassy areas, garden plants, in wood piles, that to some will represent an unsightly mess.

A side bar to this is the following: my wife gets on my case about cleaning out our roof gutters (eaves) but if twigs and leaves collect along with water this is an ideal place for myxomycete plasmodia and fruiting bodies.

I hope this helps!!

Best wishes,

Harold”

Thanks Daniel for taking the trouble to email Dr. Harold Keller. Several useful suggestions (very friendly sounding too) - I'm ready to give it a go, especially with the vast amount of rain we're having here in the UK at the moment. I did once read about a woman who kept her compost pile in a constant state of saturation in order to cultivate fungi or slime moulds, can't remember. I have a feeling it was slime moulds. I've had fungi growing from our compost but not, as far as I'm aware, slime moulds. Here goes to mulching...

for my senior project in college, i had the great fortune of keeping several wild collected plasmodial slime molds alive as pets. other than near daily watering, they were quite content living in increasingly larger containers and eating oatmeal in the dark and humid basement mycology lab. eventually most of them out grew petri dishes and i transferred them over to large crispers!

however, trying to make them fruit and display the striking form shown in this photo was another story. i think my problem was the humid air in the lab, most of the literature i read suggested cutting back on food and gradual drying to produce the fruiting bodies.

An interesting aspect of Physarum in its actively feeding vegetative stage, called the plasmodium, is that if allowed to dry quickly it forms a dull yellowish crust that can survive for long periods.
When moistened and especially with food such as rolled oats will come to active life again. I often kept this dormant crusty stage on pieces of filter paper (paper towel will do) in an envelope in a drawer taking it out when I wished to reinstitute its active feeding stage for teaching purposes.

Special

Gorgeous. They look highly edible (hence the "chocolate tube slime" name), though I would doubt if they are.

I have some of these thread like brown slimemolds in my yard. I didn't touch it, but I did blow on it and a cloud of spores (I assume) blew up into my face. Is this poisonous? I can't find anything online on the health hazards it has towards humans.

Well, I'm not a medical professional, so I can't give any specific advice. I do know, though, that we breathe in a number of organic substances (spores, pollen) each day with little ill effect (excepting asthma and similar conditions).

I had what I believe to be this particular slime mold (it was not confirmed microscopically) grow in my dining room windowsill after 2 weeks of heavy rain and damp weather. Some grew downwards and the individual tubes were easy to see, while another cluster grew upwards and resembled tiny chocolate brown volcanoes until you got close to them. They were the height of a quarter before I spotted them after 2 days away from home, so they must have grown pretty quickly. Unfortunately, it grew inside my windowsill, which meant that it and the entire window had to go. It is not edible (to humans, anyway) but is fascinating to look at.