Mendocino coast paintbrush – State Wildlife Action Plan

Mendocino coast paintbrush is a tap rooted perennial herb with few to many, decumbent to ascending branching stems arising 17-65 cm from a woody caudex. Generally covered with shaggy-bristly, nonglandular hairs that give the plant a gray-green hue. The somewhat fleshy leaves are 5-20 mm long, oblong to rounded, cupped, with 0-3 truncate-rounded lobes. Inflorescences are 5-20 cm long, with widely wedge shaped to widely obovate bracts, 15-20 mm wide, bright red to orange-red distally, and 0-3 lobes with truncate-rounded tips. Calyces, shaggy-hairy (some hairs may be glandular) and colored similarly to bracts, are 20-31 mm long with abaxial and adaxial clefts about 50% (8-12 mm) of calyx length and deeper than the lateral clefts of 10-15% (2-6 mm). Straight or slightly curved corollas are 30-45 mm long, with a 18-20 mm tube, and 15-25 mm exserted beak that is adaxially green or green-yellow and shaggy-puberulent; deep green lower lip is about 2 mm long.

Overview

Species Common Name Mendocino coast paintbrush
Species Scientific Name Castilleja mendocinensis
Federal Listing Status Species of Concern
State Listing Status Endangered

Ecoregions

Columbia Plateau

The Columbia Plateau ecoregion was shaped by cataclysmic floods and large deposits of wind-borne silt and sand earlier in its geological history. It is dominated by a rolling landscape of arid lowlands dissected by several important rivers, and extends from the eastern slopes of the Cascades Mountains, south and east from the Columbia River to the Blue Mountains.

Special needs

Mendocino coast paintbrush occurs on the edges of headlands and coastal bluffs in coastal shrub vegetation.

Limiting factors

Habitat is limited. Threats are significant and include development, recreational activities, erosion, invasive plants, and habitat fragmentation. Hybridization with Castilleja litoralis is a threat that can result in the loss of the pure C. mendocinensis genotype. Issues related to small population size are also threats. The species is also extremely vulnerable to climate change.

Data gaps

Assess genetic diversity and possible hybridization with Castilleja litoralis. Establish minimum viable population size.

Conservation actions

Protect, maintain, and restore habitat. Limit disturbance at known sites. Monitor existing populations. Collect and bank seed as insurance against local extirpation or extinction and to use in ex-situ research.

Key reference or plan

Marshall, DA. 2024. 2024 listing status assessment for Castilleja mendocinensis (Mendocino coast paintbrush). Oregon Department of Agriculture, Salem, Oregon.