Weed seeds corkscrew

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.)

Corkscrew Rush Plant Growing Profile

David Beaulieu is a landscaping expert and plant photographer, with 20 years of experience. He was in the nursery business for over a decade, working with a large variety of plants. David has been interviewed by numerous newspapers and national U.S. magazines, such as Woman’s World and American Way.

The Spruce / Adrienne Legault

Twisted or “Corkscrew” rush is called Juncus effusus by botanists. In the North, the plant is an herbaceous perennial (prune off the browned stems in early spring). In hotter regions, it is semi-evergreen; in fact, it can even be invasive in some of the warm climates, due to its ability to spread via rhizomes.

A number of cultivars are on the market, offering variations in height. For example:

  • J. effusus ‘Curly Wurly’ (up to 8 inches tall)
  • J. effusus ‘Big Twister’ (up to 1 foot tall, but often stays shorter)
  • J. effusus ‘Spiralis’ (12-18 inches tall)
  • J.effusus ‘Quartz Creek’ (18-36 inches tall)

Plant Description

Crazily twisted stems spiral out of control from their clumps in ways that are sure to delight all who have an appreciation for whimsy in the landscape. The curly stems of this foliage plant are dark green in color, making them a good foil for plants with foliage of a lighter color.

Preferred Growing Conditions, Care

Corkscrew rush plants are often listed as perennials for planting zones 4 to 9, but there isn’t much consensus on this point. Some sources say the plants are cold-hardy only to zone 6.

Grow these perennials in full sun (partial shade in the more southerly zones). The main thing to remember is that they like wet soil, regardless of soil type. Since the species plant, Juncus effusus (see below) often grows at the edges of marshes or even a few inches into the water, you know they will tolerate boggy soil. Either a neutral or an acidic soil pH is fine.

Little care is required to grow this plant. Apply an all-purpose fertilizer or manure tea in spring. Prune away stems that have browned. Happily, these are deer-resistant perennials.

The Spruce / Adrienne Legault

The Spruce / Adrienne Legault

The Spruce / Adrienne Legault

The Best Landscaping Use Is for Water Gardens

Because of their ability to grow in a few inches of standing water, corkscrew rush plants present you with a couple of options when assembling water gardens:

  • Grow them in containers, which can be sunken into the water (just don’t bury the crowns more than 3 to 4 inches)
  • Grow them in the ground around the margins of the water feature

If you can spare a few stems, cut them and add them to a floral arrangement, where they will provide just as much as pizzazz as they do in your water garden. They are highly architectural plants and make a powerful statement in almost any situation.

More About the Species (Juncus effusus)

The species that grows wild across much of the world bears the common names “soft rush” and “common rush.” J. effusus is native to North America and various other continents. It grows in clumps to a height of 2 to 4 feet with a similar spread. Common rush produces clusters of small, greenish-yellow flowers throughout the summer.

But the wild version lacks the spiraling stems that make the cultivars, J. effusus ‘Big Twister,’ J. effusus ‘Spiralis,’ etc. such highly ornamental landscape plants. Common rush has rather uninteresting, straight stems. It grows in full sun and in wet ground (even in shallow standing water). A rhizomatous plant, it is useful for soil erosion control.

A shorter type of wild rush (one foot tall or less) that you may consider a weed is path rush (J. tenuis). True to its common name, it can thrive in the compacted soil of the path that parallels a driveway. In his highly useful weed-identification book, Wild Urban Plants of the Northeast, Peter Del Tredici quips, “Path rush is one of the few plants treated in this book for which humans have found few uses.” (300)

How Do Rushes, Sedges, and Grasses Differ?

Because most people are familiar with the concept of “grass” and unfamiliar with the concepts of “rush” and “sedge,” plants in the latter two categories are often misidentified as grasses. Here’s a basic breakdown of the three plant families: