Predatory Fungus in Soil

This is a gruesome example of how nutrients can move through the soil food web. Drawing this scene was complicated and very challenging, but I learned a lot in the process. The other soil life illustrations took about 10-15 hours each, this one took 32 hours over the course of several weeks. I had to leave and come back to it a few times, and I’m still not sure if it’s really finished. It might be one of those pieces that never really feels finished because there is so much to look at, but I had to draw the line (no pun intended) somewhere.

This drawing requires a bit of explanation, unless you’re a soil biologist or just know a lot about the soil food web.

The main subject of this illustration is the big worm, which looks kind of like an earthworm but is actually a nematode. Nematodes are roundworms are usually very small and are unsegmented, unlike earthworms. There are over 25,000 known species of nematodes, but they are so ubiquitous that scientists estimate there are actually about a million different species of them. If you’re an avid gardener or maintain a lawn you might have heard of nematodes before, either to help fight pests or as pests themselves. I’ve seen packages of parasitic nematodes in garden centers that people can buy as a biological pest control against grubs in their lawn.

Soil nematodes are very small; you usually need a decent microscope to see them. There are a few main types of soil nematodes that gardeners are interested in: fungal feeding, bacteria feeding, predatory, and root feeding nematodes. They have specialized mouthparts according to their diet. The nematode pictured here is a root feeding nematode, with a needle-like mouthpiece called a stylet used for piercing through plant roots to feed on them. This can cause bulges or lesions in the roots, which are not good for the plant.

The fungus pictured is Arthrobotrys dactyloides. You can find a very good video demonstrating how it traps nematodes here. I used this video as a reference to get a better idea of how the fungus should look, since I’ve never seen one in the microscope myself.

Nematodes don’t have any eyes, so they find their food by sensing chemicals in the area, kind of like our sense of smell. The fungus emits something to attract the nematodes into the rings, and when the nematode swims through the ring it senses the heat and the ring cells rapidly swell up like balloons, trapping the nematode and killing it. Then, fungal hyphae (like roots) grow into the nematode’s body and begin to digest it from the inside.

In the illustration, all this is happening on the surface of a plant root. A plant which is probably very happy to have the fungus around protecting its roots from hungry nematodes.

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As usual, if you look closely you can also see some other small critters in the picture. There are two small flagellates just above the plant root between two root hairs on the left side, and a ciliate just below and to the left of the nematode’s head. There are also scattered bacteria, demonstrating just how ridiculously small bacteria are, so small that even at this scale they just look like little specks of debris.

I kept the soil background relatively simple in this drawing because it was already busy enough with all the scraggly root hairs and fungal hyphae. I wanted to make sure it was easy to focus on the nematode and the fact that it’s trapped.

I hope this drawing, along with the others in the soil life series, will help demonstrate how complex, fascinating, and alive the soil ecosystem really is. It is essential that we as gardeners or farmers take care of our soil by protecting and encouraging a diverse and thriving soil ecosystem. Just being a bit more aware of what goes on down there is the first step towards more sustainable food production on any scale.

There are still more drawings to come in this series. I’ve already started the next one, which features some of my favourite protozoa. Here is a sneak preview of the work in progress:

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If you would like to use my existing artwork in a publication or display, or if you want to discuss commissions of any kind, feel free to contact me using the contact button above, or you can email me directly: artborean@gmail.com.

 

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Arctic Tern Painting and Winter Update

This acrylic canvas painting of an Arctic Tern was a Christmas present, so now that the gift has been given I can post it here:

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Tux’s family lives near the coast, and when we visit I enjoy watching terns hover over the water, scouting for fish before they strike. As usual with phone pictures, the colours and lighting have been exaggerated a bit. Sometimes I wish I had a giant scanner just for paintings because taking pictures of them can be quite a challenge if the lighting isn’t ideal, and in my studio it’s far from ideal.

This time of year it’s almost always dark in the house. It’s near the base of  a large hill which is higher than the winter sun, so regardless of windows we can’t see the sun at all in the depth of winter. On nice days we still get blue skies and light of course, and on a sunny day I can determine approximately where behind the hill the sun is, but we can’t see the sun itself. Now I understand why so many holidays were originally based on things like the changing seasons; we are eagerly waiting for those first golden rays to reach over the trees signaling the return of warmth and light. After living in the city for three years, now I finally understand the Norwegian love of sitting in the sunshine, and why the easter holiday is such a big deal here. On one of the first days when I was in Canada this past Christmas, I realized it was sunny outside and I stepped out onto the porch, eager to feel the warmth on my skin, but it was -15C and that didn’t quite go as I expected. I hurried back inside before my feet froze to the deck boards. It was sunny almost every day while I was there, and not every day was that cold (boxing day was +9!), so now I consider going home for Christmas to be my “sunny holiday” for the winter. Norwegians go to Spain, I go to Canada 😉

I still love winter, and we have plenty to keep ourselves busy indoors, we just can’t do much outside these days because the whole landscape is a sheet of ice. 

It’s so slippery even the cat wipes out!

I sit inside painting and planning the coming gardens, waiting. It will be a relief when we can just walk outside and not worry about breaking a wrist or tailbone. I’ve got some lovely new bruises just from walking across the backyard to check on our new wildlife camera.

Speaking of which, here is our first catch from the “critter cam”!

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There have been loads of fox tracks around and we were told that a fox lived under the barn, which is why I’m determined to keep our kitty indoors at night as much as possible. It was fun to finally see the fox itself. I’ve seen lots of moose and deer tracks in this spot too, and we were told there are badgers around too, but so far haven’t had pictures of anything other than this fox and a neighbour’s cat prowling around.

As soon as I arrived back in Norway after Christmas, exhausted and jet lagged, we took a 10 hour drive up to Trondheim to pick up our “new” 40 year old electric garden tractor, which we are very excited about. The tractor came with solar panels for charging, so it’s totally self sufficient and emission free. These were never sold in Norway; it was imported from the states and as far as we know it’s the only one of its kind here, so we are absolutely thrilled to have it. It’s something we can fix ourselves if it breaks down since it was built before everything was so high tech and built to be “disposable”, so things were made to be fixable. The tractor came with all kinds of attachments, and we are super excited to see what it is capable of. I especially love how quiet it is compared to the diesel tractor or the gas lawn mower.

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Now things are starting to feel normal for the first time in what feels like forever. There are no more major life changes on the horizon. We’re settled in, the chaos of the holidays is over and I’m recovered from all the travel and getting back into work mode. I’ve got a contract coming up soon so I have had to push myself a bit to get back into drawing, which is always difficult if I’ve been away from it for a while, especially picking up where I left off on a work in progress. The current project involves a nematode being trapped by a fungus, like this. Nature can be pretty gruesome!

Hope you’re staying cozy and warm this winter 🙂

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Winter from the kitchen window ❤