Cheatgrass, also known as downy brome and downy chess, Bromus tectorum (grass family Poaceae) is a very small grass that has become a major weed. Generally we think of problems increasing as plants get bigger. Individual plants of cheatgrass are almost too small to notice. It makes up for that in numbers.
| patch of cheatgrass along a trail (red) |
Particular plant species generally have particular habitats where you will find them. Rainfall, temperature range, shade, soil characteristics and disturbance (level of trampling or grazing or similar effects) determining where a plant thrives and where it does not survive. Thus, if you go looking for flowers, which ones you find depends on where you walk.
We tend to see the same ones over and over, because they grow well where people walk, liking the sunniness and not minding being stepped on sometimes. Conversely, hikers will likely see quite different plants when they get a mile into the wilderness area
| Rocky Mountain forest wildflower blanket flower, Gaillardia aristida |
Teasels, Dipsacus fullonum and Dipsacus sativus, in the teasel family, Dipsacaceae, for centuries were essential to the clothing industry. Today, in North America, they are noxious weeds.
| teasel showing the seed heads |
Tansy is a small plant with bright yellow flowers and a spicy smell (scientific name, Tanacetum vulgare sunflower family, Asteraceae). It is native to western Asia but long ago became an herb and spice that was grown throughout Europe and then transported by Europeans all over the world. Today we know it more as a garden flower or roadside weed than as a flavoring or medicine, but it is all of those.
| common tansy, Tanacetum vulgare |
| buffalo burr, Solanum rostratum |
"We have a marketing failure with natives," Doug Tallamy wrote in Nature's Best Hope. While I think the "grow natives" movement is helping correct that, the fact that many natives are called weeds does discourage loving them.
| fireweed, Chamerion |
Lots of our native plants are weeds. That is, they have weed in their common name. Fireweed (Chamerion), milkweed (Asclepias), jewelweed (Impatiens), Joe Pye weed (Eutrochium), and ironweed (Vernonia) to name a few.
As a group, the plants in the mustard or cabbage family, Brassicaceae, are cool weather plants, growing well early in the spring, flowering as the temperatures warm, going to seed in the heat of summer. Familiar mustards are cabbage (Brassica oleracea), broccoli (Brassica oleracea), and mustard itself (mustards are species of Brassica, Rhamphospermum and Sinapsis). These edible mustard family plants were domesticated in Eurasia and they are a small selection of the more than 3,700 species worldwide. North America has 634 native species in the mustard family. It also has more than 100 exotic mustards.
| common mallow, Malva neglecta |
Then you look down and think, "oh just a weed."
Some places in the U.S., creeping Jenny (Lysimachia nummularia, primrose family Primulaceae) is a weed, some places a ground cover.
This spring I've been gardening daily. My current Garden Concept is a space of native plants, that welcomes the insects that eat them and the birds that consume the insects. But I like plants, so I have no intention of digging out the peonies or lilacs, even though they support very few native insects. With that complex approach, I took a look at my garden and discovered it was even more complicated.
Horsetails are odd enough that long ago when I knew very few plant names, I saw one and asked "what is this?" The hollow jointed stems are not like much of anything else. I learned not just that it was a horsetail, but that its an ancient plant. My college textbooks spoke of fossiles from the Carboniferous, 300 million years ago, that are virtually unchanged in structure; the genus Equisetum might be the oldest surviving genus of plants on earth. There were horsetails 60 feet (18 meters) tall. Today there are still some in Mexico and Central America that grow to 20'. Wow.
| Equisetum, horsetails |
| wild lettuce, probably prickly lettuce, Lactuca serriola |
Burdocks are plants you recognize for their seed pods or leaves. Oh, they have pretty enough pink-purple flowers, much like thistles flowers, but the seed pods have spines with hooks that stick tightly to clothes or fur, and the leaves are very large.
| burdock, Arctium |
I grew up calling it Indian paintbrush, so when I went west and was shown Indian paintbrush, I was puzzled. Currently, the websites say hawkweed is Hieracium, and Indian paintbrush is Castilleja. No relation between them. So I've learned to call the plant hawkweed. Actually, orange hawkweed, Hieracium aurantiacum or Pilosella aurantiaca.
| orange hawkweed, Hieracium aurantiacum |
Growing in my back yard since I bought the house in 2006 is a plant I only just learned a name for. Its Ajuga reptans, a little mint native to Europe that is used as a ground cover. My friend called it ajuga, and ajuga is used as its common name. Reading about it, I discovered the common name in USDA plant list (link) is bugle. Googling it sends you to bugleweed.
| bugleweed, Ajuga repens |
Knowing it as ground cover, I was surprised to find it mentioned as a medicinal plant.
But searching for more information on its medicinal qualities, I found I was often reading about Lycopus. For example, when I followed "bugleweed for thyroidism" I arrived at an article for Lycopus virginicus.
Lycopus is another mint genus, taller than Ajuga, with some plants native to North America.
Purslane (Portulaca oleracea, purslane family Portulaceae) is a very widespread, common plant.
| purslane, Portulaca oleracea |
So much has been written about it that mostly I'm going to remind you to notice it.
My major professor, Herbert G. Baker, caused a stir in academic botany in 1965 by publishing a list of the characteristics of an "ideal" weed. Since weeds are not popular, an ideal one is a troubling idea.
What Baker did was to look at the characteristics of successful weeds and reduce them to a list, characters of plants highly adapted to reproducing rapidly under any conditions. No real plant has all those characteristics, but some have several.
The paper made me look analytically at troublesome, weedy plants...and reluctantly admire their resilience and productivity. Fifty-seven years later, these are still good ideas.
Facebook gardening groups post pictures of plants found in their yards and ask "Is this a plant or a weed?" Botanically that is a terrible statement because all weeds are plants, though not all plants are weeds. But what the writer meant was, "Is this a desirable or undesirable plant?"
We can identify the plant, and if the property owner didn't plant it, then it will likely be called a weed.
But that is so limited! I'd like at least a third category.
We're far enough into the growing season that the bindweeds are flowering and the dandelions are ready for a second round of flowers. I try to weed part of the yard every day.
One thing I noticed was that although my lawn started the season full of dandelions, my prairie did not. My prairie is maybe 500 square feet that I planted with native grasses and forbs (non-grass herbs) a decade ago. It isn't a great success--some weedy grasses are too common--but I don't water it and my maintenance is confined to weeding out exotics and occasionally cutting back the grasses to mimic natural disturbance such as bison grazing. By the time I got to the 800th tiny dandelion plant in the lawn--an area the size of the prairie--I was struck by the fact that there were only a couple dandelions in the prairie.
| my "prairie" |
What does that suggest?
Walking in Boulder (earlier blog), many of the "wildflowers" were European species that have become naturalized in the U.S. Some are sufficiently common to be recognized as weeds. And yet, they can be beautiful.
Suppress your attitude toward these plants and notice them as flowers,purple salsify, Tragopogon porrifolius (sunflower family Asteraceae) |