About 100 perennial species make up the Solidago, most being found in the meadows and pastures, along roads, ditches and waste areas in . There are a handful of species from each of Mexico, South America, and Eurasia. Some American species have also been introduced into some 250 years ago.
Many species are difficult to distinguish. Probably due to their bright, golden yellow flower heads blooming in late summer, the goldenrod is often unfairly blamed for causing in humans. The pollen causing these allergy problems is mainly produced by (Ambrosia sp.), blooming at the same time as the goldenrod, but is wind-pollinated. Goldenrod is too heavy and sticky to be blown far from the flowers, and is thus mainly pollinated by insects. Frequent handling of goldenrod and other flowers, however, can cause allergic reactions, leading some florists to change occupation.
Goldenrods are easily recognized by their golden inflorescence with hundreds of small capitula, but some are spike-like and other have auxiliary .
They have slender , usually hairless but S. canadensis shows hairs on the upper stem. They can grow to a length between 60 cm and 1.5 m.
Their alternate leaves are linear to lanceolate. Their margins are usually finely to sharply serrated.
Propagation is by wind-disseminated or by underground . They form patches that are actually vegetative of a single plant.