Home » Plants & Animals » North American Wildflowers » Confusing Paintbrushes in Montana

Confusing Paintbrushes in Montana

© Gregg Pasterick

While the entire Snapdragon/Figwort (Scrophulariaceae) Family put on a big show in Montana, and the penstemons may have been the star act, the paintbrushes stole a scene or two, particularly late in the summer in subalpine environments. Some of them were, as usual, difficult to identify. Or maybe it was all of them.

Early in the season ... late May into June ... Harsh Paintbrush (Castilleja hispida) was the common species in bloom. As it faded, Common Paintbrush (C. miniata) took its place, lasting into September. Neither species were new to me.

Common Paintbrush is well-named, for I have seen it in the Sierra Nevada Mountains as well as the Cascades. And now here it was in the Rockies. Harsh Paintbrush is a Pacific Northwest species, western Montana being about as far east as it gets.

There wasn't much confusion where these two were concerned. They have different blooming seasons, they prefer different environments, and Common Paintbrush has flat, lance-shaped leaves where Harsh Paintbrush's leaves have three to five lobes. But as we got knee deep in summer, and Rosy Paintbrush (C. rhexifolia) began to bloom, it got a little more challenging.

The rosy to pink to purplish bracts of this paintbrush make it one of the loveliest, and bring to mind those magenta-colored paintbrushes of the Cascades and Olympic Mountains in Washington. It grows in subalpine meadows and alpine tundra, and is often confused with Common Paintbrush, mostly because it also has simple, lance-shaped leaves, and its flowers sometimes drift toward the scarlet end of the spectrum while those of Common Paintbrush sometimes drift toward the rosy end. Common Paintbrush gets much taller however; Rosy Paintbrush gets no more than 12 inches tall. Up around Logan Pass and along the Hidden Lake Trail in Glacier National Park, it was typically only about six inches tall. And it was in these locations that it grew with a yellow species of paintbrush, Sulphur Paintbrush (C. sulphurea). Or was it Western Paintbrush (C. occidentalis)?

Sulphur Paintbrush is considered to be closely related to Rosy Paintbrush; Western Paintbrush is considered by some to be a dwarf alpine form of Sulphur Paintbrush. Sulphur Paintbrush can get as tall as 12 inches; Western Paintbrush grows to eight inches or less in height. Both have lance-shaped leaves. Sulphur Paintbrush can be found from the plains to subalpine regions; Western Paintbrush stays higher up, in subalpine and alpine zones. Up on the pass, it could have been either yellow species.