Most of the rich cottonwood forests that house the bald eagle, give us recreation areas and wood, provide habitat for dozens of other plant species and beautify our waterways. Tamarisk, also known as salt cedar, is a non-native tree that was first introduced to the Southwest from Eurasia at the turn of the century. It is still planted as an ornamental landscape tree. It didn't become invasive, however, until after we straightened and dammed our waterways. Flooding may be the key to both the loss of our bosque and its reclamation.
Cottonwood trees depend on over-bank flooding to become established by seed.
The unpredictable and meandering Rio Grande, with its shallow, braiding streams, provided optimal habitat for cottonwood establishment, but this unpredictability was not optimal for other, economic interests. Thus, we straightened and dammed the Middle Rio Grande. That had positive results for development, but this major alteration began a dramatic decline in cottonwood establishment and an explosion in tamarisk. Between 1918 and 1989, tamarisk cover along the Rio Grande between Cochiti and San Marcial increased from nothing to more than 17,000 acres. Very few people are happy about it.