The term POPLARS refers to a type of tree that is found in many parts of the world. Two related species are ASPENS and ALAMOS, both of which are six-letter words. Aspens are a type of poplar tree that is native to North America and Europe, while Alamos are a type of poplar tree that is native to Mexico and Central America. Both species of poplar trees are known for their tall, slender trunks and their bright green leaves.