Burning also converted mixed stands of trees to (i)_____forest, for example the longleaf, slash pine, and scrub oak forests of the southeastern U.S. natural fires do account for some of this vegetation, but regular burning clearly (ii)_____it. Burning also influenced forest composition in the tropics, where natural fires are rare. An example is the pine-dominant forests of Nicaragua, where warm temperatures and heavy rainfall naturally favor (iii)_____tropical or rain forests. While there are primarily grow in cooler, drier, higher elevations, regions where such vegetation is in large part natural and even prehuman.