Extent of Salt Cedar Invasion in the U.S.

Extent of Salt Cedar Invasion in the U.S.: The known extent of Salt Cedar (Tamarix sp.) invasion in the United States. The vertical line marks the 100th meridian, west of which rainfall drops below 45 cm yr−1 and agriculture becomes highly dependent on irrigation.

Credit: Copyright © (2000) Royal Swedish Academy of Sciences. Originally published by Erika Zavaleta in AMBIO 29:8. Reprinted by permission of Allen Press Publishing Services.