At a site near Rock Valley, Nevada, dominated by volcanic rocks, both Larrea tridentata (Sesse & Moc. ex DC.) Cov. and Lycium andersonii A. Gray were restricted in distribution. Larrea tridentata did not grow in the many small washes in the area, but L. andersonii grew only in the washes. Ambrosia dumosa (A. Gray) Payne was more dense and more dominant in wash areas than in nonwash areas.
Wallace, A.; Romney, E. M.; and Hunter, R. B.
"Relationship of small washes to the distribution of Lycium andersonii and Larrea tridentata at a site in the northern Mojave Desert,"
Great Basin Naturalist Memoirs: Vol. 4
, Article 12.
Available at: http://scholarsarchive.byu.edu/gbnm/vol4/iss1/12