HPIPM:Goldenrod

Taxonomy

Domain	Eukarya
Kingdom	Plantae
Phylum	Magnoliophyta
Class	Magnoliopsida
Superorder	Asteranae
Order	Asterales
Family	Asteraceae
Subfamily	Asteroideae
Tribe	Astereae
Genus	Solidago

Scientific Name

Solidago canadensis

Common Name

Canada goldenrod

Goldenrod (Solidago canadensis)

Compiled by Mark B. Major, Montana State University, Teton County Extension

and Marjolein Schat, Montana State University from the following sources:

http://www.oardc.ohio-state.edu/weedguide/singlerecord.asp?id=960

http://plants.usda.gov/java/profile?symbol=SOCA6

Coladonato, Milo. 1993. Solidago canadensis. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: http://www.fs.fed.us/database/feis/plants/forb/solcan/introductory.html [2008, October].

Identification and Life Cycle

Goldenrod (Solidago canadensis) is a perennial in the sunflower family (Asteraceae). The extensive root system is very deep and fibrous with 2- to 5-inch-long rhizomes (horizontal underground stems) emerging at the base of aerial stems. Rhizomes are often reddish. Seed leaves (cotyledons) are small and elliptical. Young leaves are round, bluish green, pale beneath, and bitter tasting. The first leaves produced are basal and hairless or with a few hairs on the edge. Later leaves are rough due to hairs on the edge and underneath on the veins. Young leaves are 3-nerved, meaning the midrib and 2 parallel lateral veins are prominent. Young stems are purple-stained. Stems are 1 to 5 feet tall, leafy, mostly unbranched, slender, hairless in the lower half, and have small soft hairs in upper half below the flowers. Leaves are alternate (1 leaf per node), narrow, lance-shaped, tapered at both ends, sharply toothed around the edge, hairless on the upper surface, and hairy beneath especially on the veins. Basal leaves form but fall off early leaving only stem leaves that are all nearly the same size. Leaves lack stalks (petioles), so bases attach directly to the stem. Flower heads form in dense, elongated, pyramid-shaped clusters. Each flower head consists of 9 to 17 yellow ray flowers surrounding fewer than 10 yellow disk flowers. Flower heads are less that 1/8-inch wide. Single-seeded fruits are orange, approximately 1/20 inch long, and tipped with a tuft of white hairs (pappus).

Habitats

The species does not tolerate frequent disturbances, so it is mainly found growing in perennial crops, abandoned fields, ditches, roadsides, riverbanks, creek margins, open woodlands, and floodplains. It prefers moist conditions and medium textured soils. Goldenrod usually does not establish on very wet or dry sites, and it is fairly intolerant of shade.

Impacts

Goldenrod is not a serious weed in annual crops, and it seldom reaches densities that are a problem in rangelands. It does, however, invade poorly managed pastures and can be a pest in forest nurseries, perennial gardens, and crops.

Biology and Ecology

Plants reproduce by way of short rhizomes (horizontal underground stems) emerging from the base of aerial stems and by wind dispersed seeds. Flowering begins in mid-August and continues through October. Plants usually do not flower until the second year of growth. Goldenrod plants produce and average of 3000 seeds per plant. A pappus at the tip of each seed aids in wind dispersal; goldenrod seeds released 3 feet off the ground traveled an average of 2 feet in a 5-mph wind. Rhizomes are usually not produced until after the first year of growth. Several rhizomes grow outward from the same root crown resulting in a circular cluster of stems between 2 to 5 inches apart. Patches of shoots produced by rhizomes arising from a single root system were observed growing up to 8 feet wide.

Biological Control

There are no biological control agents available for goldenrod.

Mechanical and Cultural Control

Shallow plowing in fall followed the following year by planting crops that tolerate cultivation can control goldenrod.

Chemical Control

The response of Canada goldenrod to herbicides is affected by the lifestage of the plants. For herbicide recommendations for specific grain rotations and weeds in Montana, please see the MSU Herbicide Chooser Tool.

Examples of herbicides that can be used to manage goldenrod

Consult herbicide labels for additional rate, application, and safety information. Additional herbicide information can be found at http://www.greenbook.net.

Due to constantly changing labels, laws and regulations, the sponsors of this web site assume no liability for the suggested use of any chemicals noted in the management section. Contact your local pest management personnel for current information on labeled pesticides that can be used for the intended plant disease, insect pest or weed.

References

For more information and images please visit IPM Bugwood. http://www.ipmimages.org/search/action.cfm?q=solidago%20canadensis&Start=1&results=18