White Avens is an erect native perennial plant, 1 to 2 feet high. Stems are slightly hairy above and more so lower; round, slender and occasionally branched. The upper stem will develop into a branched cluster of up to three flower stalks.
Leaves consist of stalked lower basal leaves that have three (sometimes five), toothed leaflets, while the upper stem leaves are smaller toothed leaflets or single leaves with three major lobes. The terminal leaflet is always larger. Upper leaves are either sessile or with very short stalks. Leaves, especially the lower, have a bit of a wrinkled appearance.
The inflorescence is an open branched cluster of up to 3 flowers.
Flowers are 1/2 inch wide, 5-parted, on long stalks, and the well-spaced white (or pale greenish-yellow) petals, as long or longer than the green sepals, and somewhat resemble a blackberry flower. Sepals reflex as they mature as shown below. They have hair on the back side and margins. The petals surround a cluster of stamens which in turn surround in the center a cluster of over one hundred green carpels with elongated jointed styles, which eventually become the hooks of the seed. The stamens have green filaments and yellow anthers. The bases of the styles have fine hair, not glandular.
Seed: This arrangement matures into a round cluster of achenes which have the old flower styles extending outward with a hook at their tips which catches fur and clothing as a means of dispersing the seed. Mature seeds are brown, flattened, with some fine whitish hair, and with the style residue attached resemble a hockey stick.
Habitat: The plant grows from a rhizome, has a taproot, and is usually found in open woods, disturbed sites and thickets with partial to full sun.
Names: The genus, Geum, is an old Latin name for plants in the Avens group - said to have been used by Pliny in his natural history. The species, canadense, refers to 'of Canada'. The author name for the plant classification - ‘Jacq.’ is for Nikolaus Joseph von Jacquin (1727-1817), Dutch botanist who became Professor of Botany and Chemistry at the University of Vienna where he was also director of the botanical gardens.
Comparisons: The Yellow Avens, G. aleppicum is also similar and when not in flower, one must look to the leaves which are more lobed and the plant overall is much more hairy.
Above: The inflorescence is a loose stalked cluster with up to three flower heads. Note the complex arrangement of the flower head with the petals as long or longer than the green sepals.
Below: The lower basal leaves are on stalks and 3-parted. The sepals, no longer than the petals, begin to curve backward as the flower fully opens.
Above: Upper leaves can be single with three prominent lobes or as shown below - with three separate lobes. The mature flower head, shows the sepals folded backward (above) and in the photo below the achenes forming with the long styles still attached with a hook formed on the end. At maturity this hook will catch on passing fur or clothing to spread the seed. Note the fine hair between the seeds.
Below: Mature seeds separated from the seed head are brown, flattened, with some fine whitish hair, and with the style residue attached resemble a hockey stick.
Notes: White Avens is indigenous to the Garden area. Eloise Butler catalogued it on May 25, 1907. This plant is native to Minnesota and is found in most counties throughout the state except the Arrowhead and a few other scattered northern counties. In North America is covers most of the eastern 2/3rds of the continent.
There are six species of Geum, or Avens, found in Minnesota. Besides this species they are G. aleppicum , Yellow Avens; G. laciniatum, Rough Avens; G. macrophyllum, Large-leaf Avens; G. rivale, Water Avens; and G. triflorum, Prairie Smoke. Most are widespread, except for G. macrophyllum: G. aleppicum, G. triflorum and G. rivale are also in the Garden.
Lore: The only mention of ethnobotanical use of this plant is in Frances Densmore's study of the Minnesota Chippewa (Ref.#5) where she was told the root of the plant was collected and used to treat female weakness but she was not given the preparation specifics, which would usually have been to create a decoction and take internally.
References: Plant characteristics are generally from sources 1A, 32, W2, W3, W7 & W8 plus others as specifically applied. Distribution principally from W1, W2 and 28C. Planting history generally from 1, 4 & 4a. Other sources by specific reference. See Reference List for details.
Identification booklet for most of the flowering forbs and small flowering shrubs of the Eloise Butler Wildflower Garden. Details Here.
Friends of the Wild Flower Garden, Inc. Text and photos are by G. D. Bebeau unless otherwise credited. "www.friendsofthewildflowergarden.org"