Did you ever notice how once you start looking hard at something and identifying it, you begin to see it everywhere? I used to cut my own firewood and started seeing dead snags along every forest road. Then I learned about different kinds of rocks and pretty soon while driving my wife would ask me to please stop staring at the rocks. Well, now I can identify a few kinds of grasses and just can’t help noticing them everywhere.
This was not a “the grass is always greener” kind of thing. If I had been raising animals that browse on grass, hopefully I would be more aware of what goes on with it. I have planted grasses on my underground house and have a lawn of sorts. I used what the seed supplier recommended and now have a lot of those varieties of grass without really understanding much about them.
What got me interested in grass was the way it improves soil. “The height of vegetation on grasslands varies with the amount of rainfall. Some grasses might be under a foot tall, while others can grow as high as seven feet. Their roots can extend three to six feet deep into the soil. The combination of underground biomass with moderate rainfall—heavy rain can wash away nutrients—tends to make grassland soils very fertile and appealing for agricultural use.” (NationalGeographic.com) I also remembered reading in Centennial by James A. Michener about farmers breaking the virgin sod in Colorado where the roots were as thick as your wrist.
Our soils in Northeast Washington are mostly conifer forest soils that are not particularly rich. Deciduous trees that drop their leaves every fall make for much richer soils, but ironically since the nutrients in wet leaves are broken down by microbes rather quickly, they can leach out of the soil more easily.
I began to wonder what is going on with grasses and soil on my place and asked Tamara Beltz, cattle rancher and employee of the Stevens County Noxious Weed Control Board, for help. Together we collected samples of a dozen different grasses. I knew common names for many of them, but those are not much help for research. What I discovered is that there are reasons every grass grows where it does and uses for each as well.
Let’s start with Quackgrass. It turns out that our “Quackgrass” is not everyone else’s. In the Midwest quackgrass is elymus repens AKA couch grass. Ours is smooth brome. It likes good soil and can grow several feet high. It has very aggressive roots that travel under the surface which makes it the bane of gardeners. But actually it is good forage and works well with alfalfa. It takes a little over a month to recover from grazing depending on water. It is high in protein and low in fiber. It is great as erosion control.
Of course some of us just want to get rid of it. Having spent many hours sifting it out of a new garden bed this spring I’m not a big fan. I recommend a 10 inch underground root barrier to keep it from coming back into a garden bed. If you can wait for a season, cover the grass with cardboard and the cardboard with wood chips or spoiled hay. You can place plants in holes dug through the cardboard in the spring.
My house is covered in an orchard grass mix. As it turns out, orchard grass is a valid varietal name for dactylis glomerata l. Ironically it is best grown for pasture in intensive rotational grazing systems not just orchards. According to the USDA, it is a “long-lived, introduced, cool season bunchgrass.” Let’s break that description down a little. It is a perennial (so long-lived) that was developed into several commercial varieties that were sold (introduced) widely. It grows well in the cool and moist spring weather but with roots up to 2 feet deep, it comes back well after being grazed.
This is a good time to note that grass does best when it is eaten down or mowed at least once a year. The ability to spring back after being eaten down to around 4 inches is the key to rotational grazing. The additional light and space from grazing, the deep root systems that give grass a competitive edge over annual weeds when bouncing back and the manure and urine left by grazing herds all make grasslands continuously rich sources of feed and at least when they are first tilled, great agricultural soil.
These traits go very wrong if a pasture is eaten down continuously by cattle that will eat their favorite plants into extinction before eating ever-less palatable plants until only weeds remain. Once the grass is destroyed by tilling, the ground continues to lose organic matter and natural fertility. In Braiding Sweetgrass, a book reviewed by Loren Cruden in the September, 2020 issue of the North Columbia Monthly, Robin Wall Kimmerer relates a story about a student of hers who did a detailed study of Sweetgrass trying to determine whether pulling it or clipping it led to better reproduction. Male professors scoffed at the idea that either method would be better than just leaving it alone. But the study showed without question that “natural” stands which were not harvested were dying out while those that were harvested of half their crop by either pulling or clipping continued to thrive.
Rye grass was in the mix of grasses that stabilized the clay soil on my house. This is another bunch grass. It is also good forage for the same reasons as orchard grass. Originally from Europe, it has been widely cultivated for forage, lawns and soil stabilization. Since it cross-pollinates there are many varieties and although the USDA says it grows 1 to 2 feet tall, I have stands that are 6 feet tall on a wet year.
Both on my place and in some nearby fields the rye grass can grow so thickly that almost all other plants are shaded out. That may be good for hay and pasture but tends to deprive the soil of nitrogen from nitrogen fixers such as clover and lupine. Another benefit of these bunch grasses is that they bounce back from fire while keeping the soil in place.
One more plant considered to be a bunch grass is fescue. Commonly recognized as a grass suitable for lawns, fescue does not spread as rapidly as the others mentioned here but stands up to wear and can grow in thickly even with frequent mowing. It needs the thatch removed to provide space for new green growth. Somehow a favorite variety for lawns is called tall fescue.
We used to have a nasty kind of cheat grass with seeds that would embed themselves in your socks, animal fur or anything else that could spread them far and wide. Amazingly, that irritating cheat grass has been replaced by a fast-growing plant that turns otherwise bare ground into a green carpet in the Spring, and then quickly fades into a red blush with seed heads hanging down called drooping brome. These annual grasses rely on bare ground, lots of seeds, a quick start in the spring and seed production before the ground dries up. They are a staple food of sage grouse because they mature so quickly. Our crop springs up where the snow plow clears out other plants.
One more grass with a bad reputation is crab grass. It grows annually from seed but not very high. So it crops up in lawns where the mower does not affect it. Our variety seems to be Digitaria Ischaemum or smooth crabgrass. Digitaria refers to the finger-like crown of leaves. Although others despise it, I love crab grass. It was the first plant to fill in the aisles between my grape rows and it does not need mowing or much water. Lots of wildflowers pop up in it with no competition for light and it stays green all summer.
Tamara and I found several other kinds of grass, but enough is enough. You get the idea. There are lots of different kinds of grasses and once you start recognizing them, you can really annoy your friends by talking about something they would just as soon ignore. More importantly, grass grows best when being used and managed by people and animals. Green pastoral landscapes in family farm country are beautiful examples of humans and nature working together.