Good girl, Jarrah!
Tamarisks are pretty, but they can be problematic because they tie up so much of the water resources and concentrate salt in their foliage. They need soaking rains for the seeds to germinate, though, which may be why they're not spreading very quickly, but they also propagate by runners. In the US there are huge extermination programs going on in areas where they've taken over the landscape around rivers and lakes...
"We are--each of us--dying; it's how we live in the meantime that makes the difference."
"It's not what you gather, but what you scatter that tells what kind of life you have lived!"
"Be kinder than necessary, for everyone you meet is fighting some kind of battle."