157b. Stem smooth, at least below the inflorescence --161. 158a. Involucre 2-2.7 mm. long =Goldenrod, Solidago canadensis.= 158b. Involucre 3-5 mm. long --159. 159a. Leaves pinnately veined, scabrous above =Goldenrod, Solidago rugosa.= 159b. Leaves 3-5-ribbed, pubescent but not scabrous above --160. 160a. Stem and lower side of leaves covered with short hairs; common species =Goldenrod, Solidago altissima.= 160b. Stem and lower side of leaves with distinct, loose, soft hairs (shore of Lake Superior) =Goldenrod, Solidago altissima var. procera.= 161a. Involucre 2-2.7 mm. long (5-20 dm. high) --158a. 161b. Involucre 3-6 mm. long --162. 162a. Racemes or branches of the panicle either short and arranged along a more or less elongated axis, or elongated and ascending, scarcely recurved, forming a narrow more or less elongated panicle (5-10 dm. high) =Goldenrod, Solidago speciosa var. angustata.= 162b. Racemes or branches of the panicle usually elongated, spreading outward, usually recurved, forming a widened panicle; leaves distinctly serrate --163. 163a. Leaves pinnately veined (5-12 dm. high) =Goldenrod, Solidago ulmifolia.= 163b. Leaves 3-5-ribbed (5-20 dm. high) --164. 164a. Leaves glabrous on both sides =Goldenrod, Solidago serotina.= 164b. Leaves slightly pubescent beneath =Goldenrod, Solidago serotina var. gigantea.= 165a. Ray-flowers pistillate (the 2-lobed style protrudes from their base) --166. 165b. Ray-flowers with neither stamens nor pistil --174. 166a. Principal leaves more than 2 dm. long (1-3 m. high; summer) --167. 166b. Principal leaves less than 1.5 dm. long --168. 167a. Leaves deeply lobed =Compass Plant, Silphium laciniatum.= 167b. Leaves toothed or serrate =Elecampane, Inula helenium.= 168a. Leaves narrowly linear (3-6 dm. high; late summer) =Sneezeweed, Helenium tenuifolium.= 168b. Leaves of a broader shape --169. 169a. Heads 1-2 cm. wide; flowers in spring and early summer (2-8 dm. high) (Ragwort) --170. 169b. Heads 2-5 cm. wide; flowers in late summer and autumn --173. 170a. Basal leaves cordate at base =Ragwort, Senecio aureus.= 170b. Basal leaves narrowed to the base --171. 171a. Basal leaves obovate =Ragwort, Senecio obovatus.= 171b. Basal leaves oblong =Ragwort, Senecio balsamitae.= 172a. Introduced annual in waste places (1-4 dm. high; spring and summer) =Groundsel, Senecio vulgaris.=