Banyan trees

Used with permission by Le Vaomatua

Banyans (aoa) are fascinating plants. Although banyans give life to countless animals by feeding them with their fruit, all banyans start out as killers—stranglers, to be exact. Another name for the banyan is "strangler fig."

Most plants, of course, sprout from seeds that have fallen to the ground, and grow up toward the sun. Banyans usually do the opposite: they sprout from seeds that have been left by birds high in a tree, and grow down toward the ground. The seedling first anchors itself by sending roots into the little pocket of decaying leaves or moss where it has sprouted, then it wraps more and more roots around the tree that supports it, called the "host" tree. Soon the banyan's roots are spreading down the trunk, and finally they reach all the way to the ground. By then the fate of the host tree is sealed. It is literally buried beneath the growing banyan—strangled to death. Eventually the body of the host tree decays away, leaving no trace behind, except sometimes a long hollow extending up inside the middle of the full-grown banyan. Because banyans will start life on almost any type of host tree, they kill very few of any particular kind, and so are no threat to other plant species.

Aoa are the most important tree species for bats and fruit doves. There are two reasons why they are so important. First, banyans give fruit to a variety of creatures. When one of the huge banyans has a crop of fruit, its spreading crown has room for a whole army of hungry birds. The second reason why banyans are so important is that they fruit throughout the year. Between 10-30% of banyan trees have ripe fruit in any given month. This means that a fruit-eater can always find banyan fruit, even if all other fruits were out of season.

In addition to their supplying animal foods, aoa trees also provide homes for many animals. From its open, sheltered base to its spreading, fruit-laden crown, a banyan tree is a haven for wildlife, including Samoa's insect eaters.

Sadly, banyans today are under threat in American Samoa. Many were severely damaged by hurricanes in 1990-91. Many others have been cut down, and more are threatened by continued development, particularly in the Tafuna Plain. Some of the most magnificent banyans that still stand have been make into gigantic trash barrels, their hollow trunks filled with mounds of used diapers and rusting cans. This garbage is sometimes burned, which can kill the banyan even if that is not intended.