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Curly Dock

Naturally, you’re inclined to remove plants and weeds that are known to be invasive, noxious, and toxic. There’s no question about it.

However, the Curly Dock could be considered a crop to harvest. But that would depend on whether or not you have a pasture or garden and if you’re already growing crops.

Keep reading to learn about curly dock and decide whether it’s welcome in your landscape.

A Curly Dock (Rumex Crispus) Plant That Is Very Mature And In Its Seed Stage. Curly Dock Plants Are Green When They Are Young And Turn Red As They Mature. They Contain A Decent Amount Of Oxalic Acid.

A Curly Identification

Rumex crispus L. is a perennial weed with a deep, fleshy taproot. It grows in full sunlight and partial shade throughout the US and Canada, except for the Nunavat Province.

Its other names include the curled dock, narrowleaf dock, yellow dock (for its roots), and sour dock (for its taste).


The hairless green three-sided seeds appear in late summer and fall. They have sharp points on each end and are encased in leafy capsules that turn brown when aging.

During the winter, you can easily identify the Curly Dock because its seeds remain on the dead stem until spring.


At its maturity, the main stem is 1–5 feet tall. It appears ribbed, stout, and mostly unbranched.


On the stems are shiny, spatula-shaped leaves that become reddish purple throughout the growing season. Sprouted young leaves are smooth and egg-shaped, and when mature, they have curly edges, hence the name Curly Dock.

The bottom (basal) leaves are about 12 inches long and 2½ inches wide. The leaves on the stem’s upper portions are shorter, about 6–8 inches long, and 1–2 inches wide.


These small and greenish (or yellowish or pinkish) clusters of 6–24-inch flowers emerge in June and throughout the summer. They become reddish brown and dry when the weed reaches maturity.

Brief History of the Curly Dock

Curled dock is native to Europe and parts of Africa and Asia. In the early 1600s, the British accidentally introduced it as a seed contaminant in New England when bringing over crops and cattle.

Today, it’s considered the most widely distributed weed in the world, not just in the US and Canada.

What Makes it a Weed?

A maroon inflorescence of a curly dock plant growing among grasses and flowers in a meadow on a sunny day

The Curly Dock doesn’t take over like other weeds, but its production of hundreds to thousands of seeds is still problematic. When they’re not germinating, the seeds remain viable in disturbed and rich soil for 50–80 years.

Once the weed produces the seeds, wind, and water will disperse them. The root fragments are another spreading option if the weeds aren’t removed completely and not burned or disposed of.

Issues and Damages

You don’t want this weed in your pastures if you have livestock. The Curly Dock is toxic to your horses, cattle, and sheep, and the seeds are just as dangerous to your poultry.

Of course, they’d have to eat them in large amounts before the weeds’ soluble oxalates poison them. But that’s not a risk worth taking.

Also, know that Curly Docks will crowd and choke crops and other native plants. They also serve as a host to viruses, fungi, and nematodes that cause crop diseases. Those are grounds for weed removal.

Weed Control Measures

Rumex crispus, the curly dock, curled dock or yellow dock, is a perennial flowering plant in the family Polygonaceae

First and foremost, avoid pulling the dock by hand so the torn roots don’t resprout new weeds.

Though getting rid of this dock plant is difficult, here are a few proper ways to eliminate it.


Since curled dock doesn’t grow well in tilled soil, tillage is one way to either prevent or manage it. But check the soil for any dock weed fragments to gather up after tilling.


Mowing on mature populations will reduce top growth and stop seed production. Repeat this process routinely or combine this method with a chemical one for effective results.


If you have a small population of Curly Docks, dig them out with a shovel. After you’ve gathered them, burn or bag them and throw the bag in the trash to prevent spreading.

Spraying Herbicides

Apply a post-emergent herbicide to actively growing weeds in spring or early summer. For established weeds, apply the herbicide in the fall. Ingredients like glyphosate, metsulfuron, and 2,4-D will help destroy narrowleaf dock.

Benefits of Curly Docks

Curly dock bloom with seeds shows green perennial plant close up with blurred foreground.

Despite its toxicity to livestock, sour dock is good for people to eat! Depending on where you live, it can serve as a food or herbal supply if removing the weed is too overwhelming.


Curly Dock is in the same family as rhubarb and sorrel; their oxalic acid makes them taste sour. However, if this weed grows in moist and rich soil, it’ll have a better flavor.

Harvest docks when they’re young and tender, but before they reach their full height and the flowers bloom. Aged weeds are bitter and potentially dangerous to eat, so don’t harvest those. As for the seeds, strip them from the stem when they’re brown and dry.

You can cook the leaves or eat them fresh; the stems are best peeled, steamed, or sautéed. The seeds are a good source of fiber and can be ground into flour after you sift them for debris.


The roots in yellow dock have a laxative effect of relieving constipation and aiding in digestion. They’ll also treat urinary tract infections, irritable bowel, and bloating and help your liver function as it should. When you apply the roots topically, they’ll soothe inflaming skin conditions.

After cleaning them, boil them into decoctions (hot or cold) or tea blends and ingest or apply them when necessary.

In general, you can eat the entire weed as a remedial herb for inflammation.

Wrapping up the Curly Dock

While it might be an unwelcome party-crasher in your garden, curly dock isn’t quite the threat that other weeds are. You actually have options regarding the weed’s presence in your yard.

Unless you have crops and livestock, you won’t have to prioritize dock removal if you decide to harvest the weed. Whatever your choice and landscape situation, just be sure to take steps to keep it from being noxious (or obnoxious).

If you feel like you need to learn more about these pesky garden tenants, check out our weeds page to learn all about different weed varieties, treatment options, and surprising information.