Sugar maple flowers that are fertilized in spring, will develop into mature seeds in late summer. The seeds come in the form of winged samaras (sometimes referred to as helicopters or whirligigs). Sugar maple samaras develop in pairs but generally, only have one viable seed per pair. In late summer of heavy seed years, tree crowns can appear brown as the wings change color from green to tan or brown. The wing shape allows for the seed to travel 100 yards or more beyond the parent tree, which in turn increases the survival rate and genetic diversity of the species. Maple seeds germinate at around 34 degrees F. This is one of the lowest germination temperatures of all forest trees and germinated seed can regularly be found before the snow disappears. Sugar maple is generally very successful at germinating, with roughly 95% success rate. But just because a seed germinates doesn't guarantee it will grow to become a tappable tree. Less than 50% of all seedlings survive the first year and since many species of wildlife enjoy the seeds as a food source, the numbers go down from there.