15 cm ruler for scale
Slender, erect annual with a few branches mid-stem. Leaves linear, opposite, typical leaf measured at 3.5 cm long and 4 mm wide. Bottom of leaves with very fine hairs, stems also with small hairs. Flowers are tubular, white, with a yellow lip, borne in upper leaf axils. Flowers measured at 12 mm long and 3 mm wide.
Habitat is dry woodlands, boreal forest. Listed as common to Saskatchewan's forests by several sources.
Height listed in Budd's Flora from 15 to 50 cm; I measured plants to 23 cm tall.
Took the above photos late June 26th, trail through jack pine and white spruce woods, La Ronge Provincial Park, about 650 km north of our home in Regina, SK.