The big leaf maple (acer macrophyllum, Oregon maple) is a tall broadleaf tree, reaching up to 35 meters in height. It has large branches that start up high and droop downward, and are a popular host for moss and lichen. The leaves on the big leaf maple are simple and wide with five lobes, and are oppositely arranged. The litterfall is bigger than the Douglas-fir, and the leaves have high concentrations of potassium and calcium, helping add to its use as a soil-building species The seeds it produces are called samaras, which are winged and paired. They grow in groups of three to six and are shaped like a moth. Big leaf maple stats producing flowers ten years after it sprouts and continues to produce them every year. It is native to western North America, mainly the Pacific coast, with stands in the foothills of the Sierra Nevada mountain range and a small population in Idaho. Not found in Southeast Alaska or the San Francisco Bay Area, but can be found south in the Santa Cruz and Santa Lucia mountains.