''Trichostema laxum'' is a species of flowering plant in the

mint family The Lamiaceae ( ) or Labiatae are a family of flowering plants commonly known as the mint, deadnettle or sage family. Many of the plants are aromatic in all parts and include widely used culinary herbs like basil, mint, rosemary, sage, savory, ...

, known by the common name turpentine weed from the foliage's scent.Jepson: ''Trichostema laxum''
/ref>

Distribution

The

annual plant An annual plant is a plant that completes its life cycle, from germination to the production of seeds, within one growing season, and then dies. The length of growing seasons and period in which they take place vary according to geographical ...

is native to northern

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

and

Oregon Oregon () is a U.S. state, state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington (state), Washington, while the Snake River delineates much of it ...

, at elevations below . It is found primarily in the Inner Northern

California Coast Ranges The Coast Ranges of California span from Del Norte or Humboldt County, California, south to Santa Barbara County. The other three coastal California mountain ranges are the Transverse Ranges, Peninsular Ranges and the Klamath Mountains. P ...

, including the subranges of the

Klamath Mountains The Klamath Mountains are a rugged and lightly populated mountain range in northwestern California and southwestern Oregon in the western United States. As a mountain system within both the greater Pacific Coast Ranges and the California Coast R ...

and the

Mayacamas Mountains The Mayacamas Mountains are located in northwestern California in the United States. The mountain range is part of the Northern Inner Coast Ranges, of the California Coast Ranges System. Geography The Mayacamas Mountains are located south of the ...

.Calflora: Distribution map in California
/ref> It grows in gravelly streambanks or sandy soil, of the mountains and foothills in

chaparral Chaparral ( ) is a shrubland plant community and geographical feature found primarily in the U.S. state of California, in southern Oregon, and in the northern portion of the Baja California Peninsula in Mexico. It is shaped by a Mediterranean c ...

, Foothill

oak woodland An oak woodland is a plant community with a tree canopy dominated by oaks (''Quercus spp.''). In terms of canopy closure, oak woodlands are intermediate between oak savanna, which is more open, and oak forest, which is more closed. Although the ...

, and

Yellow pine forest Ponderosa pine forest is a plant association and plant community dominated by ponderosa pine and found in western North America. It is found from the Rocky Mountains to the Pacific Coast Ranges in the Western United States and Western Canada. In ...

habitats. The species has an affinity for

serpentine soil Serpentine soil is an uncommon soil type produced by weathered ultramafic rock such as peridotite and its metamorphic derivatives such as serpentinite. More precisely, serpentine soil contains minerals of the serpentine subgroup, especially anti ...

Description

''Trichostema laxum'' is an annual herb approaching in maximum height. Its aromatic foliage, with a strong

turpentine Turpentine (which is also called spirit of turpentine, oil of turpentine, terebenthene, terebinthine and (colloquially) turps) is a fluid obtained by the distillation of resin harvested from living trees, mainly pines. Mainly used as a special ...

odor, is coated in glandular and nonglandular hairs. The lanceolate to narrowly ovate leaves are up to 7 centimeters long. The

inflorescence An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...

is a series of clusters of flowers located at each leaf pair. Each flower has a hairy calyx of green or reddish

sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 The term ''sepalum'' was coined b ...

s and a tubular, lipped purple corolla. The four

stamen The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filame ...

s are long and curved, measuring up to 1.6 centimeters in length. Its bloom period is from June to October.

References

External links

Calflora: ''Trichostema laxum'' (Turpentine weed)Jepson Manual eFlora (TJM2) treatment of ''Trichostema laxum''USDA Plants Profile for ''Trichostema laxum'' (turpentine weed)UC Photos gallery: ''Trichostema laxum''
laxum Flora of California Flora of Oregon Natural history of the California chaparral and woodlands Natural history of the California Coast Ranges Flora of the Klamath Mountains Mayacamas Mountains Flora without expected TNC conservation status {{Lamiaceae-stub