In Big Cottonwood Park there are lots of Russian Olive trees. Well, actually they are all over in the valley. They were introduced intentionally in the 1800's as an ornamental tree. It has beautiful silver foliage. It tolerates varying water, soil, and temperature. They have really thrived in the Western US. So now it is considered an invasive weed because it is doing so well that it is displacing native utah trees like the cotton tree or the willow. They are everywhere and they make a lovely dense sage colored landscape.