Flower:

One or more leafy spikes up to 4 inches long at the top of the stem, tightly packed with club-shaped yellow flowers. Flowers are 1/3 to ½ inch long, tubular with 2 lips, inflated above with an obscure hook at the tip. Inside the tube are 2 pairs of stamens rising from the base of the upper lip, and a single style. The calyx tube is about ¼ the length of the flower, densely glandular hairy with four narrow, triangular lobes that are shorter than the calyx tube. A leaf-like, 3-lobed bract subtends the flower, densely glandular hairy, green or purple-tinged, those lower on the spike up to 1 inch long and becoming smaller as they ascend the spike.

Leaves and stems:

Leaves are alternate, crowded along stems and branches, stiffly erect or ascending, toothless, stalkless the lower stem leaves linear to narrowly lance-linear, ¾ to 2 inches long, often purple-tinged, becoming sharply three lobed up into the leafy flower clusters. The stem is stiffly erect, typically a deep purplish red, often unbranched but may have multiple branches in the upper plant. Plants are densely glandular hairy throughout.

Fruit:

Fruit is a small oblong capsule, nestled within the dried, persistent calyx and about the same length as the calyx tube.

Notes:

Interestingly, Yellow Owl's-clover bears little resemblance to true clovers, nor is it even remotely related. It is related to the paintbrushes (Castilleja spp.), betonys (Pedicularis spp.) and broomrapes (Orobanche spp.) and like them, semi-parasitic on surrounding plants. Common throughout dry western prairies, the eastern edge of its range extends just into NW Minnesota where it has never been very common. It is easy to identify from the leafy spikes with club-shaped yellow flowers and dense covering of glandular hairs throughout.