Archive for the weeds tag

Identify and eradicate stinging nettle weeds

June 27, 2023 • Leave a Comment

Stinging nettle (Urtica dioica) foliage & flowers (photo credit: MSU Extension) — **Stinging nettle (*Urtica dioica*) foliage & flowers (photo credit: MSU Extension)**

by Bev Moss

We are fighting an ongoing battle with nasty stinging nettle weeds. I pulled them a couple times last year, but they kept coming back. How do we prevent them from returning? K.L., Farmington Hills

Stinging nettles (Urtica dioica) get their nasty rap from the sharp hairs on their leaves. These hairs inject irritants into the skin which then cause swelling and itching. You can neutralize the effects by applying soap, milk, or a diluted solution of baking soda on the affected area.

Looking similar to a stinging nettle, “white dead-nettle” is a hairy perennial with heart-shaped, deeply toothed leaves. Dense whorls of white, hooded flowers appear up the stem, among the leaves. So check www.canr.msu.edu/resources/stinging-nettle-urtica-dioica to make sure you have the right plant.

Pulling nettles only causes root growth as they form a rhizomatic network underground. Your best attack is to cut them off low to the ground before they flower and hand spray a solution of two percent glyphosate to the raw cut. This takes the herbicide to that plant root and prevents regrowth. You may have to do this several times over the course of a season to thoroughly stunt their repeat performance. Any seedlings that pop up can be dug out immediately before they create a mature root system and plant stems.

Check the border areas of your property to insure you do not have a hidden breeding crop. Seeds are plentiful from just one plant and can easily be moved by animal traffic.

Beverly Moss is the owner of Garden Rhythms.

How-To: Make a cut edge

July 12, 2022 • Leave a Comment

One of the most important parts of gardening is the edge. A nicely cut edge is a treat for the garden and the eyes, but more important, it’s a first-line defense against weeds.

Where do most of your problem weeds come from? Some blow in as seeds, some germinate from seeds that were lying dormant in the soil when you dig in the garden, and some come in with compost and mulch, but most are invaders from the edge. So what edging do you have to stop them? Maybe you have plastic, metal, wood, or no defined edge. Or maybe you have the best of all: a cut edge. Nothing completes a garden better than a cleanly cut edge.

Perhaps you are wondering how a cut edge (air edge) can work better than the other types. That means that air is the barrier that bars weeds from your beds. Air works as well as the other types of edging and is variable according to the weeds you’re trying to keep out of the garden. You can vary the depth and width of the trench that is the cut edge, depending on how deep the weed’s roots are running that you’re trying to keep out of the garden, and how far the weed’s “arms” reach.

Standard black plastic edging is between 3 and 4 inches deep. Many problem weeds will go deeper and creep under that edge into the beds. A gardener who cuts an edge can simply cut deeper for those that dive below four inches. For weeds that cross into a bed by growing over the ground and rooting from the tips of those branches, the gardener cuts the trench wider.

The steps to make a cut edge

1. Using a sharp spade, slice down through the turf, then pull back on the handle. This “pops” out the cut turf and part of the garden soil. You do this to help loosen the soil into the bed, which allows for easier pulling of the weeds creeping into the bed from the edge. You can cut an edge any time you want to, but the best time is in the spring or fall, because it has a more lasting effect.

2. Grab the cut piece of the edge and shake the excess soil into the bed. Watch for and pick up pieces of root that fall off. Save your back and vary your activities by cutting just 10 to 20 feet of edge at a time, then stop to remove the sod and weeds you’ve just cut.

3. If you feel roots break off from the weedy strip you are removing, go after them. Use a fork to loosen the soil further into the bed and remove those roots. Clean out the air trench, pushing the excess soil into the bed.

4. After you are finished, notice that you have weeded at least one foot into the bed. All that is left to weed is the interior of the bed, but the weediest area is under control now. In terms of maintenance, it is ideal to cut an edge 2 or 3 times a year: in the spring and fall, and in the summer if it needs touch-up.

**An edge cut in April still looks good at the end of July. A recut of the edge in midsummer will last the rest of the year.**

**The air edge is used by many of the world’s great botanical gardens. Here a worker is cutting an edge at the Royal Botanic Garden Edinburgh in Scotland.**

**A cut edge is a wonderful finishing touch on a bed.**

Text and photos by Steven Nikkila, www.gardenatoz.com.

MORE TIPS: How to control slugs in your garden

Getting Rid of Weeds On Organic Farms Is More Difficult Than You Think

July 14, 2017 • Leave a Comment

NPR:

This spring has been strange in Oregon’s Lane County.

“It rained every day. I’m exaggerating, but only by two days,” says farmer Jason Hunton.

When Mother Nature rears her ugly head, Hunton watches his fields. He farms both organic and conventional land in Junction City, Ore.

“We’re struggling. We’ve got a couple of [organic] fields that have some real thistle problems. I want to get some tarps and solarize it — cover it up and see if we can get that to cook itself in some of the thicker areas,” Hunton says.

Several fields down the road, a tine weeder runs through one of Hunton’s organic wheat crops. It’s like a giant comb, scraping up weeds and bits of wheat along with it.

This is the third time this year that Hunton has tine-weeded this field. It’s an all-day job. In his conventional wheat fields, he can spray once and be done with it.

Read the rest of the story…

Look beyond your vegetable garden—a salad awaits you in the weeds

June 23, 2015 • Leave a Comment

Watch this fun video featuring foraging expert Wildman Steve Brill touring New York’s Central Park in search of edible common weeds such as Garlic Mustard, Violet, Poor Man’s Pepper, Pennycress, Cattails, and more. Many of these weeds are native to Michigan as well.

Janet’s Journal: Eye to Eye With the Worst of the Garden Weeds

June 2, 2015 • 10 Comments

Here’s an intelligence report on some of the most persistent and sneakiest garden weeds of Michigan gardens. To pack the most information into available space, we’ll let pictures and vital statistics do the talking.

Most Persistent

Bindweed, Canada thistle, Ground ivy, Mexican bamboo,
Nut sedge, Scouring rush, Violets, and Wild garlic

These are some of the warriors you’ll have to kill and kill again. They are weeds that cause people to shake their heads even as I answer their question, “How do I get rid of…” The gardener may even smile ruefully while saying over and over, “No, I’ve tried that.”

If you’ve battled these and been beaten, I don’t doubt you’ve tried, but I do doubt that you understood and matched the persistence of your foe. Cut off their heads—their green, leafy source of energy—and they sprout anew from deep, extensive root systems like the mythical beast which sprouted two heads each time one was cut. Each cutting, digging or herbicide application by the gardener puts a drain on the roots’ starch reserves, but each day a new shoot gathers sun, it replenishes those roots. If you attack just once, twice or three times a year and let the survivors surface and gather sun for weeks or months during the cease-fires, you insure a perpetual war.

To best the beasts on this list, beat them at their own game. After you roust out every bit of green and as much root as you can reach, post a guard. Expect new shoots within a week. Find them and cut them before they can return to the root the starch they used in reaching the sun. Be vigilant in this follow up and you will gradually exhaust the weed’s reserves.

Wild Garlic

Wild garlic (Allium vineale), which hides its narrow foliage among grass blades, can always be identified by its smell. Survives mowing as well as grass, escapes broadleaf weed killers, and stores enough energy in the bulb to return repeatedly if weeders leave the bulb behind. Infestations are usually best handled by killing or digging out all vegetation in the area and then maintaining a thick mulch and a weeding vigil for 18 months.

Mexican bamboo

Mexican bamboo, Japanese knotweed (Polygonum cuspidatum). Perennial, up to 9 feet tall, spreading far and wide from established clumps by stout underground runners (left). Jointed, hollow stems explain the common name “bamboo.” The center section of stem has been eliminated in this photo for clarity’s sake. Grub out the roots or apply Roundup and be prepared to kill remnant sprouts for a season or two.

Canada thistle

Perennial, wickedly persistent Canada thistle—Cirsium arvense, which is not native, despite its common name. A stem and a basal clump are shown here, left of the glove. Note the running roots, which can persist and keep sprouting even through a year or two of frequent pulling or spraying with herbicide. The key to control is to be even more persistent than the plant and to adopt as a mantra what Edwin Spencer writes in All About Weeds, “…any plant can be killed—starved to death—if it is not permitted to spread its leaves for more than a few days at a time.” The annual prickly sow thistle (Sonchus aspera), immediately right of the glove, and biennial bull thistle (Cirsium vulgare), far right, are weedy but not nearly so much trouble to eliminate. Just keep pulling or cutting the annual and biennial thistles before they set seed, and keep the area well mulched to prevent existing seed in the soil from sprouting.

Violet

Violet, common blue violet (Viola sororia). Perennial, often tolerated in gardens for its blue-violet flowers in spring, yet hated for colonizing nearby lawn. A typically schizophrenic approach by gardeners! Either accept it in both places or eliminate it from both. Like ground ivy, it can be killed in lawns with broadleaf weed killer—may take repeated applications—but will then return from seed if the grass is not pampered until thick enough to shade out the seedlings.

Nut Sedge

Perennial nut sedge or yellow nutgrass (Cyperus esculentus) infuriates gardeners by returning even if pulled and pulled again. But of course it returns if the soil is not loosened deep and well so that the brown nut-like tubers come out, too. In the inset photo, note the horizontally-running root, which turns up to produce a second clump of “grass” and the new crop of nuts developing as white bulbs at root tips. Nuts can rest dormant for many years in the soil and be revived by deep excavations. Frightening to think nut sedge tubers are edible and somewhere a large-tuber form may be in development as a food crop!

Ground ivy

Ground ivy, also called gill-over-the-ground, is Glechoma hederacea, a perennial. It snakes through lawn, rooting where its stems make contact with bare soil. In gardens, freed from a mower’s restraint, it explodes to become a dense mat and can weave its way 18 inches up into stems of other plants. Shallow-rooted, it’s easily pried loose from beds and mulch will prevent it from reestablishing by seed. However, it must also be banned from adjacent lawns. The broadleaf weed killer Trimec will kill it, but the lawn must then be overseeded and thickened by better care lest ground ivy seed simply sprout and re-take the bare soil between grass plants. Sometimes confused with henbit, an annual.

Scouring rush

Field horsetail, or scouring rush (Equisetum arvense), is a native perennial often brought into gardens in tree and shrub root balls. Easiest to eradicate if caught early in its tenure on a property, otherwise it must be dug and surviving pieces starved by repeated pulling.

Bindweed flower

The trouble with focusing on flowers for identification is that the worst weeds—long-lived perennials that are slow to begin blooming—can become entrenched before we know what we’re facing. Once great bindweed (Convolvulus sepium) is large enough to show its two-inch white or pinkish flowers, it’s so well-grounded that its removal will require a two- to
three-year pitched battle.

Bindweed

Convolvulus sepium, the great bindweed (pictured) and its smaller-flowered, smaller-leaved, lower reaching cousin C. arvensis, small-flowered bindweed. Perennial. Extensive, deep, easily broken root systems. My own experience mirrors that of W. C. Muenscher who writes in the textbook Weeds, “Clean cultivation…if performed thoroughly, will control bindweed in two years. The land must be kept black, that is no green shoots should be allowed to appear above ground. Cultivation should be at frequent intervals of about six days. Under certain conditions this time may be extended a few days and under other conditions it may have to be shortened to three- or four-day intervals.

Sneakiest

Enchanter’s nightshade, Glossy buckthorn,
Pokeweed, and Yellow wood sorrel

These weeds earned places on this list by their tendency to present a false face or ride in on invited guests. Once their true natures and their avenues of entry into a garden are known, they are relatively easy to eradicate with informed pulling and thorough mulching.

Pokeweed

Pokeweed (Phytolacca americana) is an impressive, statuesque plant draped in purple-black berries in fall. Birds love this native fruit – although it is quite toxic to humans – but gardeners wish their feathered friends would eat all of the berries before they fall and then not excrete any! This photo shows the berries of an established plant – up to 9 feet tall and wide – and the roots of seedlings just 4 months old (center) and one month old (right). The roots don’t run but they do delve deep, so pull them early or be prepared to dig deep.

Enchanter’s nightshade

The native perennial, enchanter’s nightshade (Circaea canadensis) is rarely seen in sunny gardens but can drive a shady gardener wild, especially when the buried seeds ripen (right photo). In seed, it seems to pull out easily and completely, but careful loosening of the soil before pulling will reveal the new, white, nearly-detached perennial roots (left photo) which can lie quietly until the next spring.

Glossy buckthorn

Glossy buckthorn (Rhamnus cathartica) is a small tree with very bad habits. It leafs out early in spring and keeps its leaves far into fall, effectively shading out native plants wherever it sprouts. Since it can thrive in woods, sun, wet areas and dry, it’s a serious threat to native ecosystems of all kinds, as well as gardens. The seeds don’t travel far on their own. Birds eat and then drop them where they roost so the trees are common along fence lines. Fast growing, the gardener must patrol for and pull them at least once a year, and try to locate and remove the mature plants which are providing the shiny black berries. One thing gardeners can be thankful for is the plant’s shallow, fibrous root system – far easier to pull than other woody weeds such as mulberry and tree of heaven.

Yellow wood sorrel & Common wood sorrel

Yellow wood sorrel, right, (Oxalis europaea) seems frail and easy to pull, compared to its ground-hugging cousin, common wood sorrel, below, (Oxalis stricta). But like enchanter’s nightshade, the yellow wood sorrel has a deceptive root system. Pull it and it seems to come up easily, roots and all. Yet if one loosens the soil well before pulling and uses a light touch, it becomes clear how many fragile, white, running perennial roots can be left behind by the uninformed gardener. Far easier to deal with is the common wood sorrel, which does not spread below ground but only above where stems sit on moist soil and root (the pen points to such a stem).

Battling weeds in your garden

May 15, 2014 • 5 Comments

The best gardeners develop an eye that takes in the whole plant and garden—not just the flowers. One “star” of this article is evident here to the trained eye. — The best gardeners develop an eye that takes in the whole plant and garden—not just the flowers.
One “star” of this article is evident here to the trained eye.

By Janet Macunovich / Photos by Steven Nikkila

Why are weeds so hard to talk about?

We spend much of our in-garden time preventing and removing weeds. Perhaps you haven’t counted those hours, but I have, since I garden professionally and must account for my time. Bottom line? We spend 30 to 35 percent of our gardening hours in pursuit and defiance of weeds.

Every weed is a desirable plant for someone, somewhere. Scotch thistle (Onopordum acanthium) is an invited biennial guest in my garden, an impressive eight foot tall, sculptural gray form that provides seeds the finches love. But oh, what a thug it can be, seeding its dangerously sharp self all around! — Every weed is a desirable plant for someone, somewhere. Scotch thistle (*Onopordum acanthium*) is an invited biennial guest in my garden, an impressive eight foot tall, sculptural gray form that provides seeds the finches love. But oh, what a thug it can be, seeding its dangerously sharp self all around!

The books, magazines, TV shows and newspaper articles into which we pour our disposable incomes don’t seem to recognize this. Twenty magazines pulled at random from my current stash yielded 220 article titles. If topics were chosen commensurate with the attention we give a subject in our gardens, about 70 of those articles should have been weed-oriented. Yet only three titles even included the word “weed.”

Should the weed-disabled gardener hit the books? I tried it, searching in general gardening encyclopedias. An “Illustrated Guide to Gardening” was typical in its coverage, allotting just ten of its 649 pages to “Weeds and Their Control.”

Weed books do exist for those who hunt. My collection, built slowly over twenty years, consists mostly of textbooks and publications from various agricultural universities’ Extension services. Although there is plenty of useful information in “Problem Perennial Weeds of Michigan” (Michigan State University Extension bulletin E-791) and in “Weeds” (a textbook published by Cornell University Press), it’s dry, dry, dry.

Worse, the suggested control methods in textbooks and Extension bulletins are mostly geared toward agricultural and commercial users. “Repeated mowing,” “clean cultivation” or “fallowing for one season” might be practical for a farmer, but are tough to translate to the home garden. Likewise, a professional landscaper may benefit from the advice “timely spot treatment with the proper herbicide,” but most of us don’t care to know which of the many herbicides available only to professionals would work even if we could buy them because it’s not often practical to apply herbicides in established beds.

The attitude adjustment can take time but it’s the ultimate liberation to be able to talk about weeds without shame. It’s a perspective that allows me to smile and say, ‘Every weed in this article and in these pictures is my weed. I grew it!’ My weedy companions in this picture are all annuals: (left to right) lamb’s quarters, lady’s thumb, crabgrass (in my hand), buckwheat (vine), perilla (at my foot), purslane (in my hand) and Impatiens glandulifera. Please note the perilla and impatiens are invited, but self-sowing monsters—weeds, by their disposition. — The attitude adjustment can take time but it’s the ultimate liberation to be able to talk about weeds without shame. It’s a perspective that allows me to smile and say, ‘Every weed in this article and in these pictures is my weed. I grew it!’ My weedy companions in this picture are all annuals: (left to right) lamb’s quarters, lady’s thumb, crabgrass (in my hand), buckwheat (vine), perilla (at my foot), purslane (in my hand) and *Impatiens glandulifera*. Please note the perilla and impatiens are invited, but self-sowing monsters—weeds, by their disposition.

When you see that a plant has running roots that turn up into new plants, like the quack grass (Agropyron repens) has done here in the blade that crosses the trowel, roll up your sleeves! You’re taking on a perennial weed. — When you see that a plant has running roots that turn up into new plants, like the quack grass (*Agropyron repens*) has done here in the blade that crosses the trowel, roll up your sleeves! You’re taking on a perennial weed.

Bindweed (Convulvulus arvensis) tops my most-hated list. Even this short, young piece can put up a three-year battle. It’s also known as wild morning glory, for its trumpet-like flowers, white aging to pink (here closed on a cloudy day). — Bindweed (*Convulvulus arvensis*) tops my most-hated list. Even this short, young piece can put up a
three-year battle. It’s also known as wild morning glory, for its trumpet-like flowers, white aging to pink (here closed on a cloudy day).

So let’s get down and dirty. First, that means we start looking at and talking about weeds without shame. They’re an integral part of gardening, so let’s accept that and acknowledge they’ll always be with us. Stop disguising them under mulch, apologizing for them, or diverting visitors from beds where they dwell. Quit refusing to admit you’re growing any. Or many. This attitude adjustment can take time but it’s the ultimate liberation. It’s the perspective that allows me to smile as I write, “Every weed in this article and in these pictures is my weed. I grew it!”

The more we bring weeding out from under the carpet, the more we can draw on each other’s experience and help. Just think how far ahead we’d be if we shared even a tenth of the tips on weed-beating that we share on rose-growing. Talking more means we’ll also begin to look more closely at our weeds and know them better.

Don’t confuse perennial bindweed with the recently-ubiquitous, annual wild buckwheat (Polygonum convulvulus, also called hedge bindweed). Notice buckwheat’s flowers are tiny, not trumpets, and its leaves are more sharply pointed than perennial bindweed. Annual wild buckwheat is far less trouble to beat than perennial bindweed – just keep buckwheat from going to seed. — Don’t confuse perennial bindweed with annual wild buckwheat (*Polygonum convulvulus*, also called hedge bindweed). Notice buckwheat’s flowers are tiny, not trumpets, and its leaves are more sharply pointed than perennial bindweed. Annual wild buckwheat is far less trouble to beat than perennial bindweed—just keep buckwheat from going to seed.

What a wealth of information becomes available when you have a weed’s name. Look it up in the dictionary, check for it in a weed textbook, ask about it at the Extension, type its name into an Internet search engine. In knowledge is power—in this case, power to predict, undermine and eliminate.

To identify your foes, start with MSU Extension weed bulletins—several include color photos. No luck there? Flip through weed textbooks at a library. Still nameless? Press a sample of the weed, preferably with root and flower or seed pod intact, sandwich it between sections of newspaper and stack heavy weights on it for a week. Tape the flattened sample onto cardboard and take it to garden centers, garden club meetings and plant swaps. Someone will give you the name.

Even before you know your pest’s proper name you can start working on the next most important fact—is it a perennial, annual or biennial? Many perennials reveal their long-lived nature through their roots. Loosen the soil all around the weed and remove it carefully, roots intact. Look for underground runners that pop up into new plants, or bulges and knobs on a horizontal root that foretell new shoots. The presence of storage organs such as bulbs and tubers are also telltales that the plant’s either perennial or biennial. There’s no other reason for a plant to store away a lot of starch except that it’s planning to come back next year.

Ground ivy (Glechoma hederacea) is a tough perennial weed, rooting wherever it touches soil and ducking so nimbly in and out of lawn and groundcover that the whole area usually has to be killed and started over. — Ground ivy (*Glechoma hederacea*) is a tough perennial weed, rooting wherever it touches soil and ducking so nimbly in and out of lawn and groundcover that the whole area usually has to be killed and started over.

Which brings me to another “must-do” when it comes to weeds. That’s to stop looking for miracle techniques and products. Weeds caught early on, under two inches tall, can be dispatched fairly easily with a hoe or a smothering mulch. Give them a year and you’re in for a battle that requires a discriminating eye and lots of hand work.

I’m not saying I like this fact. Established perennial weeds make me cringe. That’s what’s wrong with the lead picture in this story. See that Canada thistle (Cirsium arvense) among the hostas on the left? Okay, go after it. Loosen the soil, remove every bit of root you can find. Then acknowledge the root’s depth, brittleness and tenacity by returning every week or ten days for two whole seasons, April through November, to nip off every bit of thistle that tries to make a comeback. At the end of the second year, you may have starved it out—forced it to exhaust all the reserve starch in its roots.

Tuber roots are what make yellow nutsedge (Cyperus esculentus) such a scourge. Those in the know understand that if you don’t get the nut out, you don’t get the sedge out. — Tuber roots are what make yellow nutsedge (*Cyperus esculentus*) such a scourge. Those in the know understand that if you don’t get the nut out, you don’t get the sedge out.

Perennials and biennials can stash an amazing amount of starch in their roots, given even a bit of green leaf to work from. Take a carrot (Daucus carota) in its weed form: Queen Anne’s lace. It’s as cute and small as a carrot-top in its first year – just a bunch of low, feathery leaves. Yet look what the root produced by those leaves delivers in year two—four feet of stately stem, leaf, flowers and thousands of seeds. No wonder when we leave a bit of weed root in the ground, it manages to keep sprouting for years.

Bindweed (Convulvulus arvensis) is worse. Given time to establish, its roots may dive 15 feet deep. If dug well and then nipped in the bud every six days—more frequently when the growing is good—it takes 2 to 3 years to wear it out.

Don’t confuse hedge bindweed (Polygonum convulvulus, also called wild buckwheat) with perennial bindweed. An annual, wild buckwheat is far less trouble to beat—just keep it from going to seed. That means where blown-in seed or seed-infested mulch spawns an invasion, weed thoroughly several times before mid-June.

Scouring rush or field horsetail (Equisetum arvense) drives people crazy yet it’s a wimp compared to bindweed and Canada thistle. Dig it well, focusing on those enlarged tuber roots, keep new shoots nipped weekly for one season and it’s gone.

New weeds show up all the time. Some pretend to be something planted on purpose, as this one did. When it reached eye level I decided I didn’t plant anything new that would be so big, and yanked it. We took this photo for posterity. I’ll use it to figure out what it was!

Tuber roots are what make yellow nutsedge (Cyperus esculentus) such a scourge. Pull on this weak-looking, creased-blade grassy creature and it comes readily, with what looks like all roots intact. Those in the know, however, understand that if you don’t get the nut out, you don’t get the sedge out.

Yellow wood sorrel (Oxalis florida) is another perennial that fools us by pulling easily and seeming to have little root. That’s because its running roots break loose and stay behind when we pull—a good reason to study the plant, learn that it has runners and loosen the soil well throughout the area before pulling.

Obviously, we can’t cover all weeds and weeding techniques in this article, but this is a good start!

Janet Macunovich is a professional gardener and author of the books “Designing Your Gardens and Landscape” and “Caring for Perennials.” Read more from Janet on her website www.gardenatoz.com.

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