What’s in the Mulch?

There was a golf ball in the truckload of mulch we got last year. And more than a few dozen shredded plant labels.

This year there’s enough mushrooms to feed an army – should that army be brave enough to eat them. We think Mr. Boggs was brave enough to stomach one, but we won’t expose the ghastly details of how badly he suffered for the next week and a half.

Bentley and Mr. Boggs love mulching day

The prevailing advice is to appreciate their beauty, ignore them, or remove them (the mushrooms, not the dogs). I’ve tried every approach, but would strongly recommend the latter, especially should you encounter the stinkhorn mushroom. Do.Hold.Your.Nose! (Still talking mushrooms, I think.)

An “appreciate their beauty” sort of fungi.

I took a picture of the mushrooms in the front garden last Monday. By Wednesday, they had tripled in size.

Another group of mushrooms grew up through the creeping jenny, or maybe the creeping jenny grew up through the mushrooms.

Bird’s nest fungus (Cyathus spp)

Most mulches are mixtures of shredded wood and bark residues from lumber and paper mills, arboricultural and land-clearing operations, wooden pallet disposal or recycling products – all of which decompose over time.

The recommended 3 to 4 inch layer of mulch suppresses weeds, retains moisture, controls soil erosion, provides soil nutrients, encourages beneficial soil organisms and worm activity, insulates plants from extreme temperatures (mulch reduces summer soil temperatures by as much as twenty degrees), cuts nitrous oxide emissions up to 28%, reduces the release of greenhouse gas, and it just makes things look nice. On the other hand, all sorts of strange things like to grow in that dark, moist world.

This was last year’s slime mold, also appropriately called “dog vomit” fungus. Scientifically speaking, it’s a species of Physarum, Fuligo, and Stemonitis. They start out as brightly colored (yellow, orange, etc.) slimy masses that eventually dry out and turn brown before finally turning white and powdery. They do no harm, and fortunately have no smell, even though they look absolutely horrid.

Some of these fungi are “recyclers” and break down woody tissue while others, such as slime molds, consume bacteria and other organisms living in the mulch. They show up from April to October, usually after rainy weather, and aren’t harmful to our plants or to humans – well, unless you eat them (we’re looking at you, Mr. Boggs).

There is more life below the soil surface than there is above: burrowing animals, such as moles and earthworms; insects and other soil creatures that are difficult or impossible to see without a microscope, such as mites, springtails, nematodes, viruses, algae, bacteria, yeast, actinomycetes, fungi, and protozoa.

It’s a springtail. 🤨 Springtails are probably the most abundant non-social insect on the planet. There’s approximately 650 species in the United States alone and they are found in both the Arctic and Antarctic. Large numbers in any area will show that the soil is healthy. And, by the way, they are not capable of infesting human beings. That’s a myth.

There’s roughly 50 billion microbes in 1 tablespoon of soil. Each gram of your common backyard soil (the weight of a standard paperclip) probably contains, from largest to smallest: 10 to 5,000 nematodes, 1,000 to 500,000 algae, 1,000 to 500,000 Protozoa, 5,000 to 1 million fungi, 1 million to 20 million actinomycetes, and 3 million to 500 million bacteria.

How many paper clips would fit in a garden? Let’s don’t ask.

On the happy side, these microscopic critters kill slugs, vine weevil and chafer grubs, leatherjackets, ants, carrot and cabbage root fly, sciarid flies, caterpillars, thrips and codling moths – all of which will wreck havoc in your garden if left to their own devices. It’s all about balance.

So, what’s in the mulch?

Diversity, balance. . . life. It’s a very happy place, indeed.