Flower-heads. - Golden-yellow, composed of both ray and disk-flowers.
About eighty species of golden-rod are native to the United States: of these forty-two species can be found in our Northeastern States. Many of them are difficult of identification, and it would be useless to describe any but a few of the more conspicuous forms.
A common and noticeable species which flowers early in August is S. Canadensis, with a tall stout stem from three to six feet high, lance-shaped leaves, which are usually sharply toothed and pointed, and small flower-heads clustered along the branches which spread from the upper part of the stem.
Another early flowering species is S. rugosa. This is a lower plant than S. Canadensis, with broader leaves. Still another is the dusty golden-rod, S. nemoralis, which has a hoary aspect and very bright yellow flowers which are common in dry fields.
S. lanceolata has lance-shaped or linear leaves, and flowers which grow in flat-topped clusters, unlike other members of the family; the information that this is a golden-rod often creates surprise, as for some strange reason it seems to be confused with the tansy.
The sweet golden-rod, S. odorata, is easily recognized by its fragrant, shining, dotted leaves. S. coesia, or the blue-stemmed, is a wood-species and among the latest of the year, putting forth its bright clusters for nearly the whole length of its stem long after many of its brethren look like brown wraiths of their former selves. The silver rod, S. bicolor, whose whitish flowers are a departure from the family habit, also survives the early cold and holds its own in the dry woods.
The only species native to Great Britain is S. Virga-aurea.
The generic name is from two Greek words which signify to make whole, and refer to the healing properties which have been attributed to the genus.