Canadian Goldenrod, Solidago canadensis, is a rhizomatous, upright perennial of the sunflower family. It is mostly found growing in moist conditions on abandoned farmlands, pastures, fields, thickets, prairies, waste areas and along roadsides.
Central stems are clad with numerous, narrow, alternate, lance-shaped, sharply-toothed, stalkless to short-stalked green leaves which are hairless above but hairy beneath and tapered at each end. Central stems are hairless near the base but soft hairy above the middle. Central stems rise to 4-5 feet tall and are topped in late summer to fall (August to October) with large horizontally branched terminal pyramidal panicles containing one-sided recurving branches filled with masses of tiny yellow flowers.
Several flowering stems emerge from the top of the plant in the form of a panicle bearing masses of tiny yellow flowers in compact heads. Each flower head is less than ¼-inch across. The flower head occur along the upper part of each flowering stem, and sometimes have a slight fragrance. The blooming period is from late summer to fall; individual plants typically remain in bloom about 3 weeks. The achenes are longitudinally ribbed, slightly hairy, and have small tufts of hair, which help to provide dispersion by wind. The root system is fibrous, producing creeping rhizomes that cause the plants to cluster, sometimes forming dense colonies.
Natural habitats include disturbed areas of moist to dry prairies, openings in both flood plain and upland forests, thickets, savannas, limestone glades, and gravel seeps. In more developed areas, it occurs in both cultivated and abandoned fields, vacant lots, power-line clearance areas, and along fences, roadsides, and railroads.
Easily grown in average, slightly acidic, moderately rich, well-drained soils in full sun. Tolerates light shade. Intolerant of full shade. This is a rhizomatous, spreading, somewhat weedy plant that can rapidly colonize an area by creeping rhizomes and self-seeding. Removal of flower heads prior to ripening of seed, if practicable, will help prevent seed dispersal.