“Weeds, Glorious Weeds”
Weeds are like the pop-up ads on my computer screen. They are the price of gardening. That said, nothing is as satisfying as looking back on a row or bed cleared of weeds. That hard work pays off in better veggies, flowers, shrubs and lawns. Susan Martin’s rule in this year’s June issue is never more true than with weeds: “Success is the sum of small efforts, repeated day in and day out.”
Manually yanking those suckers or mechanically hoeing and raking them on a daily routine remain the most effective assault on unwanted plants without damaging the prizes we’re nurturing. Mulching before weeds appear will help, of course. If we are starting a bed from scratch and can plan a year or more before planting, we might turn over the soil and cover it with black plastic to smother all vegetation. This last technique helps; but if you keep reading you’ll see that some seeds can stay dormant for 80 years; and almost all weeds find a way to spread from one area to another. Weeds are nothing if not persistent, which is another strike against attacking them exclusively with chemicals and risking the health of all biological organisms including yourself.
My gardening battle with weeds was revolutionized when my wife and I found that weeding comes easier with two people. Whether it’s our conversation that keeps us going or the competition to be the last one to give up, the garden looks better after working together. Whatever motivates you in the dirt, this article is an attempt to understand the enemy so all our efforts can be more effective; because weeds have to be controlled or eradicated.
By definition, weeds are plants growing where they are not wanted. In the garden, they may crowd out desired specimens, stealing nutrients, light and water as well as disrupting the appearance of your artistry. We can classify them by their life cycle as annuals, biennials, or perennials; and this may help us to formulate a long-term strategy by knowing when to expect them. Weeds can also be classified as broadleaf or grass-like to help with identification. Most of the time we just want to get rid of them so we can get back to nurturing the plants we really love. Here we’ll address some of the weeds often found in and around the Virginia Piedmont, although I confess these are mostly the ones I deal with year after year.
Broadleaf plantain
Photo: Rasbak
Broadleaf plantain (Plantago major L.) is a perennial weed with low, basal rosettes forming leaves up to 6 inches long and 4 inches wide. Leaves are often dark green with prominent veins curving from base to tip. There is a fibrous taproot which means that, as with dandelions, merely chopping the leaves is a temporary albeit worthwhile fix. Next year you can expect to see the remaining root sprout again. This plantain sports a skinny spike bearing green seed capsules that turn brown. It appears in poor, compact soil, whether in lawns, gardens or any untended places, such as my paths or neglected rows. The leaves die in winter only to come back the following spring.
Narrowleaf plantain (Plantago lanceolate), cousin of the broadleaf, is also a perennial, growing mostly in lawns. Its rosette of narrow leaves produces a naked stalk a foot or so tall with a bullet-sized seedhead. I recall many unhappy hours in childhood swinging a blade against these stalks.
Narrow leaf plantain
Common Ragweed. Could there exist a more exotic name than Ambrosia artemisiifolia, the scientific name for this bane of allergy sufferers? Also known as hay-fever weed, bitterweed, or wild tansy, it’s a summer annual preferring full sun and dry conditions. The small green and yellow flowers produce excessive pollen, the cause of much sneezing and stuffiness. Apart from the symptoms of its pollen, it can be identified by its pale, green leaves up to 4 inches long which are egg shaped, arranged slightly like a triangle and somewhat resembling a small oak leaf. Near the base of the plant beneath the leaf-like cotyledons, it shows a purple color. Although it grows in disturbed areas such as fields or roadsides, it can sprout in our gardens since seeds can survive in the soil for as much as 80 years. Dig it up before it can produce pollen or seeds.
The Common Dandelion (Taraxacum officinale) seems oblivious to its habitat, springing up in pampered lawns and gardens as well as ditches. A recent visit in Michigan showed me how hardy dandelions can serve as a welcome substitute for spring flowers in the cold Northwoods; but Virginians are less tolerant. Readers scarcely need a picture of the happy, yellow blossom, an inch across, to make an identification. It has a taproot that can penetrate 6 inches into our hard clay, which means chopping off the leaves is only temporary. Before you curse its arrival, stop to consider that the early leaves have been used as a salad by more discerning gourmets and the flowers will make a passable wine. Having taken this history into account, dig deeply and discard the deep taproot and the entire debris. Also note that simply mowing the yellow flowers before they turn into puff balls will insure that seeds never develop even though the plant will return.
Photo by Greg Hume – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=17890515
English ivy (Hedera helix) is a shade-tolerant, woody perennial vine. When established, it creates a dense ground cover with attractive dark green foliage. But, left unchecked, this introduced plant invades woodlands, climbs (and kills) trees and is considered an invasive species. Perusing the internet, you can find several “recommendations” for controlling English ivy. Some good, some are questionable, all depend on persistence. This fact sheet summarizes some of the non-chemical and chemical control options. Read more at: https://weeds.ces.ncsu.edu/2019/03/english-ivy-its-time-to-think-about-control-options/
English ivy. Photo: Whiteghost.ink – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=37335932
Yellow nutsedge (Cyperus esculentus) is a perennial that invades lawns and landscape beds as well as gardens, especially those with moist to wet soils. Its narrow leaves are yellow-green up to 8 inches long with a prominent midrib. They taper to a point, unlike the similar purple nutsedge leaves, which do not taper. The triangular stem is more yellow than lawn grass (more purple in purple nutsdge). Underground structures, small and round, called nutlets make it very difficult to control with cultivation.
Tubers and rhizomes, which reproduce the plant, may remain dormant in the ground for 10 years while it lurks in wait of more favorable conditions. The good news is that cutting the leaves at mowing height in the lawn prevents seeding, which is okay if you can tolerate the weed in your yard. It is green after all.
Yellow nutsedge. Photo courtesy of Missouri Botanical Garden
Poison Ivy (Toxicodendron radicans) is a toxic perennial as the botanical name suggests and may grow as a seedling 2-3 inches high or as a thick vine on trees or structures. The ovate leaves come in 3 distinct leaflets, irregularly toothed, green and shiny above, paler below. Leaf shape may alter, but the three leaflets give it away. The color changes to attractive red and orange in the fall before disappearing. However, toxicity does not disappear. Seeds are in a yellowish-green cluster in spring, turning toward white in summer and winter. It reproduces either from creeping roots or seeds. Its relative, eastern poison oak (T. pubescens), grows only as a shrub, but looks similar and is equally poisonous. I include it because no one wants either in their yard or garden.
I’m always surprised at people who work outdoors but cannot identify these irritating plants. Brushing the leaves releases toxin which produces spreading red bumps that itch for days. Always remember “Leaves of three, let it be.” Box elder and Virginia creeper may seem similar; but the former has opposite leaves (and grows into a tree) while poison ivy leaves alternate on the stem, and Virginia creeper has five leaflets.
When working around poison ivy, wash skin with soap and cold water within 30 minutes to reduce or eliminate the ill effects. Clothing should be washed since the toxic urushiol can be transferred to furniture and be carried on tools, pets or the soot of burning brush. The blisters which accompany itching are themselves non-allergenic and won’t themselves cause more harm. Several products are available which may reduce the reaction or help the rash. The AMA estimates that poison ivy and poison oak cause more contact dermatitis in the USA than all other plants, household chemicals, and industrial chemicals combined.
Control: Cutting poison ivy near the ground will eventually eliminate it. Digging or grubbing it out should be done with waterproof gloves. Glyphosate applied on a warm, sunny day when plants are growing will kill it; other herbicides are available. Read labels carefully.
In Vermont Garden Journal, By CHARLIE NARDOZZI • JUL 10, 2015
Ground Ivy (Glechoma hederacea) goes by many names, including ground ivy, but I like ‘creeping charlie’ because it creeps up anywhere in my yard and in the edge of the woods. Like true ivy it’s a perennial that stays green year-round, preferring moist shade but managing sunny areas all too well. The rounded leaves (1-2 inches) have large rounded teeth and stems about the same length as their diameter, growing from a square stalk along the ground. It spreads prolifically from stolons or seed.
Control of Creeping Charlie depends on its location. In the lawn, improving the health of your turf in those shady or moist areas and mowing closely will help to crowd it out. Applying a postemergence broadleaf herbicide such as triclopyr combined with another herbicide eliminates this weed with a couple of treatments in the early fall. In the garden, however these herbicides will kill most desirable vegetables and ornamentals since they are broadleaf. Of course, hand pulling Creeping Charlie and getting absolutely every one of its roots and stolons works anywhere.
Finally, although trees may not come to mind as weeds, I think of four that drop seeds and grow virulently around my house. Maple, Mimosa, Hackberry and Wild Cherry seedlings can be pulled easily when 4-5 inches. Cedar seedlings may have to be slightly taller; but all of these usually come up by the roots with a firm tug. The list of weeds and their characteristics seems endless in the guide listed below. Piedmont gardeners can be grateful for the offer of Virginia Tech agents to help with identification; just take a photo and email it to the Help Desk, albemarlevcehelpdesk@gmail.com
As in all things gardening, daily attention pays dividends. Like those apps for our computers that block pop-up ads, knowledge about weeds will help, but nothing works like deleting them on a regular basis.
SOURCES:
- Two general articles: http://weeds.cropsci.illinois.edu/weedid.htm and https://www.turffiles.ncsu.edu/weeds-in-turf/
- Specific to our area: (https://ext.vt.edu/agriculture/weed-management.html
- Virginia Tech’s guide to weed identification: https://weedid.cals.vt.edu
- Wisconsin’s Extension article on Creeping Charlie: https://hort.extension.wisc.edu/articles/creeping-charlie/
Thanks for the excellent article, David. I spend a good amount of time with weeds, so it’s always important to learn as much about them as possible. Some weeds are “nice” because you can pull them up easily. Some are “nasty” because they are tenacious and prolific. In my yard, common lespedeza fits the latter description. It has taken over the lawn in summer and jumped into my beds. It is very hard to pull. I won’t use herbicides, so I live with it. As you say, at least it’s green.
I wonder why our turf scientists haven’t figured out how to genetically modify fescue with crabgrass genes. That would give the weeds a run for the money. Just kidding of course!
At least we will be weeding in cooler weather now that fall is on its way.