Kiawe: that is what we call this variety of mesquite here in Hawaii. It is an invasive species and it just about everywhere except in higher elevations. The wood is hard and beautiful and makes for great barbecue, but the thorns on it! Oh, my! They hurt like heck when you step on it and they are sharp and long enough to pierce through whatever foot gear you might have on (or, worse yet, to have nothing on at all).
How did this variety of mesquite end up in Hawaii? In a most unlikely way:
"Prosopis pallida is native to the arid coast of northwestern South America. In 1828 it was introduced to the Hawaiian Islands by Father Alexis Bachelot, the head of the first Catholic mission to Hawaii. He planted a tree on the grounds of the Catholic Mission on Fort Street in Honolulu that he had raised from the seed of a Peruvian tree growing in the royal gardens of Paris. By 1840, the progeny of that single tree became the principal shade trees of Honolulu and were already spreading to the dry leeward plains on all of the neighbor islands, including Maui."