Amaranthus albus (Tumbleweed Amaranth)

Plant Info
Also known as: Tumble Pigweed, White Amaranth
Genus:Amaranthus
Family:Amaranthaceae (Amaranth)
Life cycle:annual
Origin:native
Status:
  • Weedy
Habitat:part shade, sun; dry disturbed sandy or gravelly soil; roadsides, railroads, gravel pits, waste places, farm fields, gardens
Bloom season:June - October
Plant height:4 to 40 inches
Wetland Indicator Status:GP: FACU MW: FACU NCNE: FACU
MN county distribution (click map to enlarge):Minnesota county distribution map
National distribution (click map to enlarge):National distribution map

Pick an image for a larger view. See the glossary for icon descriptions.

Detailed Information

Flower: Flower shape: indistinct Cluster type: spike

[photo of clusters] Tiny flowers are tightly packed in small clusters (glomerules) in a spike-like arrangement at the tip of branching stems and arising from leaf axils, with a few to several flowers in a cluster. Flowers are either male (staminate) or female (pistillate), both on the same plant (monoecious) and usually mixed within the same glomerule.

[close-up of flowers] Male flowers have 3 yellow stamens, female have a 3-parted style at the tip of an oval green ovary. Both lack petals and have 3 green sepals that are less than 2 mm long, slightly unequal in size and have a green midrib that extends to a pale spine-like tip. At the base of each flower is a bract that is similar to the sepals but about twice as long, or longer. The sepals, bracts and stalks are all smooth and hairless.

Leaves and stems: Leaf attachment: alternate Leaf type: simple

[photo of leaves] Leaves are alternate, elliptic to spatula-shaped, mostly widest above the middle toothless, hairless, wedge-shaped at the base tapering to a stalk about half as long as the blade. Edges are commonly wavy, weakly to strongly so. The tip is mostly rounded and usually has a small spine-like extension at the apex. Early lower leaves may be up to 3 inches long and 1 inch wide, but most are less than half that size, an inch or less long.

[photo of stem and branches] Stems are whitish to straw-colored to light green, usually hairless, sometimes glandular-hairy, erect (rarely prostrate), much branched, the branches ascending to spreading. A plant can become quite bushy and large plants may break off near the base, forming tumbleweeds to spread their seed.

Fruit: Fruit type: capsule/pod Fruit type: seed_without_plume

[photo of fruit] Fruit is a dry seed enclosed in the persistent ovary shell (pericarp) that has a wrinkly texture and a seam around the middle, the top coming off like a cap to expose the seed. Mature fruit is about as long as or longer than the sepals

[photo of seeds] Seeds are lens-shaped, .6 to 1 mm long, smooth, shiny dark reddish-brown to black. 

Notes:

Tumbleweed Amaranth is found in gravelly or sandy disturbed soils such as roadsides, railroads, cultivated fields, gravel pits, construction sites and vacant lots. While considered native to the central US and Canada, it has spread world-wide and has naturalized on all continents except Antarctica. It is distinguished by the erect bushy growth, small often crinkly leaves with a small spine at the tip, separate male and female flowers on the same plant, flowers with 3 sepals shorter than the floral bracts, and shiny lens-shaped seeds about 1 mm in diameter. A similar species is Prostrate Pigweed (Amaranthus blitoides), with has a prostrate growth, leaves that are usually flat not with crinkled edges, 4 or 5 sepals, bracts and sepals all similar in size, and dull black seeds 1.3 to 1.6 mm diameter.

Native Plant Nurseries, Restoration and Landscaping Services ↓

Map of native plant resources in the upper midwest

  • Shooting Star Native Seeds - Native Prairie Grass and Wildflower Seeds
  • Morning Sky Greenery - Native Prairie Plants
  • Natural Shore Technologies - Using science to improve land and water
  • Minnesota Native Landscapes - Your Ecological Problem Solvers
  • Spangle Creek Labs - Native orchids, lab propagated

More photos

Photos by K. Chayka taken in Anoka County. Photos by Peter M. Dziuk taken in Anoka, Norman and Ramsey counties, and in North Dakota

Comments

Have you seen this plant in Minnesota, or have any other comments about it?

Posted by: Lee Lucas - Coon Rapids
on: 2021-12-05 22:40:17

I saw one on Coon Rapids Boulevard right by the Fridley-Coon Rapids border.

Post a comment

Note: All comments are moderated before posting to keep the spammers out. An email address is required, but will not be posted—it will only be used for information exchange between the 2 of us (if needed) and will never be given to a 3rd party without your express permission.

For info on subjects other than plant identification (gardening, invasive species control, edible plants, etc.), please check the links and invasive species pages for additional resources.



(required)




Note: Comments or information about plants outside of Minnesota and neighboring states may not be posted because I’d like to keep the focus of this web site centered on Minnesota. Thanks for your understanding.