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Invasive Plant: Pokeweed

Information
Photo shows plant with bunches of berries growing along the top of a fence.
Pokeweed is a shrub native to the southeastern United States. It is considered edible when properly prepared but toxic to the unwary. The roots are thought to be the most toxic part of the plant, but sickness can result from eating other parts as well.
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At a Glance

Scientific name: Phytolacca americana

Why Are We Concerned?

Pokeweed is known to form dense patches that begin in disturbed urban areas (alleys, gardens) and expand into undisturbed areas. Pokeweed infestations can lead to:

  • Reduced plant and animal diversity as other plant species are displaced.
  • Human health concerns.

How Does It Spread?

Photo shows a cluster or dark purple berries along the stem of a green plant.
Birds are thought to spread pokeweed by eating the berries.

Birds are thought to be key spreaders of pokeweed berries. Resting places, like fence or powerlines, are often where people will find new plants. The striking colors of pokeweed have led many homeowners to leave the first plants in place, often regretting the choice later. Pokeweed is becoming a popular species to swap among home gardeners. Pokeweed berries are moved around by:

  • Wildlife
  • Gardeners

What Does It Look Like?

Photo shows a large root structure laying on the ground.
Roots of older plants can be 2 to 3 feet long or more.

Pokeweed has thick, fleshy stems that become bright pink by mid to late summer. After three or four years, plants can be over 6 feet tall. Leaves are smooth-edged and spade-shaped, and can be up to 10 inches long. Clusters of small creamy-white flower form mid-summer, turning into drooping bundles of dark purple berries by early fall. The roots of young plants resemble a carrot. The roots of older plants can be 2-3 feet long or more.

Are There Any Look-alikes?

Sort of. Pokeweed’s tall, upright stems, leaf shape, and tendency to fill an area are reminiscent of knotweed. The pink color and smooth, not segmented, stems help distinguish pokeweed, with longer leaves and the drooping clusters of flowers and berries.

How Do We Deal with It?

  • Manual: Digging can effectively manage pokeweed, though it often needs several years of regular attention to fully eradicate. At the very least, we suggest you clip the berries and put them in the trash (not the compost). Roots should also go in the trash; that prevents any potential spread through compost. Stems, flowers and leaves can go in compost.
  • Herbicide: Herbicide trials have been inconclusive, but suggest that a mid- to late-summer spray be effective. Contact Environmental Services for more information about possible herbicide options.

How Can Folks Help?

Pokeweed is not a species the city is currently managing on private property. Private property holders are, however, strongly encouraged to manage and properly dispose of pokeweed.

Contact

Early Detection and Rapid Response (Invasive Plants)

Environmental Services