These are trees of the
legume family, with charactaristic compound
leaves and
seed pods. They turn bright yellow in the fall, often have sharp spines, and grow very well in the
desert. In fact, they sometimes 'escape' from cultivation, although they are not as much a threat to natives as other plants like
tamarisk. They are also known as '
locust' trees. The type which is abundant in the desert of the southwestern US is
Robinia pseudoacacia, so called because it somewhat resembles an
acacia tree.
If you're going to plant a Robinia, you will probably want to get a variety which doesnt have thorns, or the seed pods, which can make a mess. Also, don't plant them in natural settings (in the US), because they may crowd out native plants. They may grow as shrubs but can be pruned into trees. They can give decent fall color and are extremely hardy - surviving where few other trees would.