Granite prickly phlox (Linanthus pungens) is a low shrub that grows erect or may be short and spreading, depending on the environment. Under good conditions, the plant can grow up to 3 feet in height, while at higher elevations mat-like forms are more common.
This native is found in western United States and British Columbia. There is also a population of granite prickly phlox in Maryland. Its habitat is dry, rocky and gravelly places from sagebrush steppes to perennial grasslands between about 4,000 to 13,000 feet. However, it can tolerate a variety of conditions.
A semi-evergreen, granite prickly phlox has several stems arising from a taproot and woody base. The stems and leaves are usually lightly hairy. The flowers and leaves are aromatic. The rigid, sharp-pointed, alternate leaves persist for one to several years. When dead the leaves turn grey and remain on the plant.
Granite prickly phlox flowers are solitary or in a cluster at the end of stems. The flowers can be white, cream, yellowish or pinkish with a yellow center. The petals are united into a narrow tube that opens into five lobes. This thin flower tube favors insect pollinators with a long proboscis. The calyx lobes are narrow and pointed at the tip and are somewhat variable in length. The single pistil has a superior ovary and a three-parted stigma. Generally the flowers open later in the day.
Fruits of granite prickly phlox are three-chambered capsules each containing 5 to 10 seeds.
A member of the Phlox Family (Polemoniaceae), L pungens is also commonly called granite gilia. Synonyms include Leptodactylon pugens and Gilia pugens. The genus name is from the Greek and means “resembling a flax flower” (linon/flax and anthos/flower). The species designation refers to the sharp leaves – “pungens” means spiny or sharp pointed.
These granite pricky phlox were photographed in July along Modoc County Road 10 just outside of the Lava Beds National Monument in California.