(271) Ornamental Characteristics of Lesquerella (Lesquerella sp.) Plants

Abstract

Lesquerella (Brassicaceae) seeds contain high concentrations of hydroxyl fatty acids with long carbon chains, similar to imported castor oil. Although species within the genus are considered as an alternative oil crop, lesquerella plants have ornamental characteristics that may present a valuable landscape alternative for dry open spaces. Seeds of certain Lesquerella species are already a component of wild flower seed mixtures sold commercially. The purpose of this study was to describe ornamental aspects of selected accessions in the USDA Lesquerella germplasm collection maintained at the National Arid Land Plant Genetic Resources Unit. From 2003 to 2005, more than 140 accessions from 30 species were characterized for selected plant characteristics. The majority of lesquerella flowers were yellow, but some species, such as L. mcvaughiana, L. mexicana, L. ovalifolia, L. pallida, L. perforata, and L. stoniensis, had white flowers. Petal length ranged from 4 to 11 mm, and the number of flowers per an unbranched stem was from two to seven. While the duration of full bloom of many lesquerella plants was between 15 to 40 days, the full bloom of plants of 10 accessions lasted from 50 (PARL 166, L. argyrea; W6 20836, L. grandiflora; W6 20841, L. lasiocarpa) to 72 days (PI 596362, L. fendleri). Those traits make the plants suitable for planting in landscape borders, low hedges, or color patches. The main use of the USDA, NPGS Lesquerella germplasm collection (201 accessions) is in cultivar development of a new oil crop. However when considering the duration of bloom and the abundance of flowers, several accessions may be used as ornamental crops, especially in semi-arid and arid landscapes where water supply is limited.