Before killing it, name that weed
I was walking with a friend through his fruit tree orchard a couple weeks ago when he knelt down to pull up a weed.
“Oh, I love that plant,” I said.
“These things are everywhere. What is it?”
“It’s called deerweed. It’s a native plant. It has little yellow and orange flowers all over. It’s really pretty and the bees and butterflies like it.”
In my yard, I cultivate deerweed. I protect it, I encourage it.
See that photo at the top? That’s an unattractive deerweed in the foreground. Looks like a dead bush, I know, but come spring it will be beautiful.
Here’s a photo of some new leaf growth on another deerweed in my yard:
When I moved into my house six years ago, half the yard was native plants with weeds and the other half was pure weeds. Some weeds I knew, like tumbleweed. I quickly set to eradicating that. But others I couldn’t identify. One such plant I came to know was deerweed, and once I learned its name I was able to learn all kinds of things about it.
Deerweed’s botanical name is Acmispon glaber or Lotus scoparius, and one of its interesting characteristics is that it’s a nitrogen fixer. What’s that? Some plants have the ability to take the nitrogen that is floating around in the air and change its chemical composition (“fix” the nitrogen) so that the plant can take it into its roots. In actual fact, the plant doesn’t do this on its own. There are bacteria that live in the soil that do the nitrogen fixing, and they live attached to the plant’s roots. The bacteria fix the nitrogen, feed it to the plant’s roots, and the plant in return feeds carbohydrates back to the bacteria. Fascinating stuff!
Most plants are incapable of having this relationship with nitrogen-fixing types of bacteria, but deerweed is one of the few. (Peas, alder trees, and clover are a few of the others.)
What is a weed, precisely?
What is a weed? To most of us, a weed is simply the label we give to a plant that is growing where we don’t want it. The concept is entirely subjective — that is, my friend thought deerweed was a weed, but I didn’t.
Weeds are not equally undesirable. I have a lot of weeds in my yard. Some of them I loathe (ripgut brome), and some of them I mildly dislike (whitestem filaree — bees do love its flowers, and it’s fun to make scissors out of its seedheads, but its corkscrew seeds stick to everything).
Wherever the native vegetation has been removed, weeds will fill in. Count on it. The earth demands that its soil surface be covered. Weeds provide this covering, and we have the opportunity to encourage or discourage whichever weeds show up.
Sometimes before pulling a weed in the garden, we should take the time to learn its name.
It’s impractical to do this every time, all the time, but over time if you learn the names of the weeds in your yard you then gain access to the information that others have gathered about them for a thousand years, and not only will you learn to manage them better but you will also declassify some as “weeds”.
Weed scientists think of weeds differently. They classify plants as weeds if the plants are very competitive and are hard to control in a landscape. So while my friend thought deerweed was a weed, no weed scientist would define it so because deerweed is neither very competitive nor hard to control. In my own yard, I’ve lost deerweed plants to actual grass weeds because the grass weeds grow very fast and produce prodigious amounts of seed; they overtake the deerweed within a year or two.
Before killing it, name that weed
I’ve got a new weed in my yard this year. It’s not totally new, but I’m seeing much more of it this year than in years past, and up until the other day I hadn’t learned its name.
How do you learn the name of a weed? One method is to use the University of California’s Weed Gallery. I took the above photo, and then I went to the Weed Gallery website and began searching.
If you use the weed gallery, you should search by using as many identifying characteristics as you can. You might have to follow many trails before finding your plant.
For example, with this plant I first clicked on “Broadleaf identification” because it doesn’t have narrow leaves like grass. Then I clicked on “whorled leaves” but that ended up not showing my plant, so I backed up and clicked “roundish (orbicular) leaves”, which also ended up not showing my plant. I wondered if my plant wasn’t in the gallery.
I looked at my photo again. Then I backed up and clicked on “lobed edges”. The plant does have lobed edges. Voila! Henbit, or Lamium amplexicaule. I have the name!
Before I went further and learned about how henbit reproduces itself, what its seedlings look like, etc., I already knew I wasn’t going to immediately remove it because while I was taking the photo of this henbit I had noticed something hanging on the lip of one of its flowers. I moved closer to get a better look. I couldn’t believe my eyes. That’s a Ceratina species!
It crawled inside the henbit flower, then it backed out. Yes, that’s a small carpenter bee, a native bee!
I hadn’t seen a single native bee in my yard yet this year, and then to see a small carpenter bee . . . on a weed. Hmmm.
Sure makes me think twice about killing the henbit, at least until the non-weeds are in bloom.
(See some amazing photos of Ceratina bees here at the U.S. Geological Survey’s Native Bee Inventory and Monitoring Program.)
Some seeds float in the wind others helicopter to the ground these interesting weed seeds of the Redstem Stork’s Bill corkscrew their way into the ground. Each “storks bill” which is the sword like projections off the plant are cluster of five seeds, each with the long tail tapering out to the end of the “bill”. These tails are tightly bound and make the central, elongated “bill”. At maturity, what becomes the corkscrew peels off the long “bill” and starts to curl, remaining attached to the seed. The familiar corkscrews then twist into the soil as they go through day-night cycles of wetting and drying, each time the spiral forces the sharp seed deeper into the soil. Eventually the seed breaks off, leaving hundreds of cork screws.
Barbs, Burrs. and Stickers
The grasses are growing taller and in some places starting to overtake the wildflowers. My family thought I was crazy for wanting to photograph them, but they have always fascinated me. The various modes of transportation these opportunistic plants use to travel and reproduce themselves are varied and clever.
As they grow larger and dry out, the Foxtails develop almost invisible barbs that grow in the opposite direction of the pointed end, so that they get caught and don’t fall out. They can burrow down into a dog’s ear or paw in a trice, and a trip to the vet is required to remove them.
The bright yellow flowers on the Burr Clover turn into little round balls resembling a tiny mace which get stuck in socks and fur. It is difficult to avoid them, and once they are inside your shoe, it is impossible to ignore them. By the end of the summer the green plant will have dried up and blown away, but the ground will be littered with the burrs.
When we were kids, we would take the long pointed seeds of the plant on the left, and poke one through the other to make “scissors”, so we always called them Scissors Plants, but they are much more talented than that. As soon as they fall off the plant they begin to dry and rotate into a “corkscrew”. All the dried corkscrews in the picture came out of Rudy’s fur. Being a Daschund with long hair, his belly is almost on the ground, and he leads with his whiskery nose as he plows through the tall stems, so he is a veritable magnet for them. Being a large black lab with smooth fur, Ozzie seems to do a better job of staying above the fray, but he will soon be a target for the foxtails.
The light colored Wild Oats are also light in weight–blowing like chaff on the slightest breeze. They have slender stems which dry and break quickly in the sun. I can understand the phrase “sowing wild oats”, knowing that in their carefree way, they will stick to anything passing, and go unnoticed until, hours later, I am shaking them out of my hair and clothes.
As I look at the abundance of grasses and seeds, which were sewed at the end of last summer and are now springing up everywhere, I could digress into the subject of what constitutes a weed, but that must be a subject for another day. I would only venture to say that a weed is something that has traveled from a place where it is abundant, like the fields of gently waving grass, to a place where it is not wanted, like my dog, my socks or my garden.