What is Mast?

What is Mast?

Mast is the botanical name for the nuts, seeds, buds, or fruits of trees and shrubs that are eaten by wildlife.

There are two main types of mast:

Hard mast includes hard nuts and seeds such as acorns, hickory nuts, and walnuts.

Soft mast includes berries and fruits such as crabapples, blueberries, and serviceberries.

Both types are important year-round food sources for wildlife, but hard mast is often considered more important, especially as a winter food source, due to its higher energy content.

The definition of mast is sometimes expanded to include the winged seeds of trees such as maple and elm, as well as pine seeds and nuts and even buds, hips, and catkins such as rose hips.

A related term is “mast seeding,” or masting, which refers to the synchronous production of large numbers of seeds or fruit by a population of plants. Some species, such as red oaks, produce seeds only once every two years. Others, such as white oaks, produce seeds every year, but occasionally have years where an entire population of trees produces an unusually large number of acorns all together. These bumper crop years are known as “mast years.”

Scientists believe that this highly variable but synchronous seed production evolved as a survival strategy. During good mast years, so many seeds are produced that the wildlife population can’t eat all of them, leaving plenty to sprout and grow.

Image credit: http://www.flickr.com/photos/hathome/37740495/