From a wildlife point of view, the tamarisk has little value and is usually considered detrimental to native animals.
The leaves, twigs and seeds are extremely low in nutrients, and, as a result, very few insects or wildlife will use them.
In one study along the lower Colorado River, tamarisk stands supported less than 1% of the winter bird life that would be found in a native plant stand.
Because of the tamarisk's ability to eliminate competition and form single-species thickets, wildlife populations have dropped dramatically.
http://www.nps.gov/whsa/tamarisk.htm
It also does a dandy job of clogging canyons to where hiking is almost impossible.