''Eriogonum caespitosum'' is a species of wild buckwheat known by the common name matted buckwheat, mat buckwheat, or cushion desert buckwheat.

Description

The species is a tough

perennial In horticulture, the term perennial ('' per-'' + '' -ennial'', "through the year") is used to differentiate a plant from shorter-lived annuals and biennials. It has thus been defined as a plant that lives more than 2 years. The term is also ...

plant which grows in flat, woody mats in sand and gravel substrates. It has small, fuzzy gray leaves (under long) which are scoop-shaped due to their rolled edges. In early summer, short stalks emerge from the mat with

inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...

s of greenish-yellow and whitish rounded clusters of flowers. These redden with age and hang backwards over the edge of the

involucre In botany, a bract is a modified or specialized leaf, associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves in size, color, shape or texture. They also look ...

. The species is

dioecious Dioecy ( ; ; adj. dioecious, ) is a characteristic of certain species that have distinct unisexual individuals, each producing either male or female gametes, either directly (in animals) or indirectly (in seed plants). Dioecious reproduction is ...

. Some of the flowers are

bisexual Bisexuality is romantic attraction, sexual attraction, or sexual behavior toward both males and females. It may also be defined as the attraction to more than one gender, to people of both the same and different gender, or the attraction t ...

and up to 1cm wide each, and some are only staminate and much smaller.

Distribution and habitat

It is a common

plant native to the western United States from

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

Montana Montana ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States. It is bordered by Idaho to the west, North Dakota to the east, South Dakota to the southeast, Wyoming to the south, an ...

, especially the

Great Basin The Great Basin () is the largest area of contiguous endorheic watersheds, those with no outlets to the ocean, in North America. It spans nearly all of Nevada, much of Utah, and portions of California, Idaho, Oregon, Wyoming, and Baja Californi ...

. It prefers middle and high elevations, from

shrub–steppe Shrub-steppe is a type of low-rainfall natural grassland. While arid, shrub-steppes have sufficient moisture to support a cover of perennial grasses or shrubs, a feature which distinguishes them from deserts. The primary ecological processes hi ...

to rocky environs.

Uses

It is cultivated as a

rock garden A rock garden, also known as a rockery and formerly as a rockwork, is a garden, or more often a part of a garden, with a landscaping framework of rocks, stones, and gravel, with planting appropriate to this setting. Usually these are small ...

plant.

References

External links

Jepson Manual TreatmentPhoto gallery
caespitosum Flora of California Flora of the Great Basin Flora of the Western United States Flora without expected TNC conservation status {{Polygonaceae-stub