African Tulip Tree

In 1871, Dr. William Hillebrand introduced the African tulip (Spathodea campanulata) to the Hawaiian Islands. This was part of an effort to restore the forests destroyed by grazing animals, and the exploitation of the native forests.

Almost 100 years earlier, in 1778, British Captain James Cook introduced goats to the Islands. In 1793 British Captain George Vancouver introduced sheep and cattle. These grazing animals were set loose on the land and quickly began to multiply. Native plants had mostly lost their defenses against animals like thorns and bitter tasting compounds. Native plants were quickly eaten by the feral animals.

Around the same time, Kamehameha I began to harvest and sell native sandalwood, ‘iliahi (Santalum ellipticum), to Asia. Native forests were also cleared to be converted into sugarcane and pineapple plantations.

By the early 1900s the forests were almost completely gone. The devastated native forests led to regular droughts in the Hawaiian Islands. Ecologists determined that the forested watersheds were important for maintaining water in the Islands. Restoring the forests was a crisis that needed immediate attention.

In an effort to quickly restore trees to the landscape, grazing animals were taken off the land, and fast growing trees were planted. In the early 1900s tens of thousands of African tulip trees were planted. In the 1920s seeds were dropped from airplanes into the native forests.

The land was saved from complete desertification, but the choice of trees had long lasting negative consequences. The African tulip spreads quickly into native forests crowding out native vegetation. The large seed pods are full of papery seeds that can float on the wind over long distances. It grows quickly, up to 6 feet a year and becomes a tall tree, up to 75 feet (25 m). The brittle wood is a hazard too. The albizia tree is another reforestation tree that poses similar problems.

Fast growing tropical trees saved the Islands from total devastation. However, many of the restored forests are full of invasive trees that are encroaching on the remaining native forests. A healthy native forest is more stable and resilient than the ad hoc mix of plants from all over the world in the restored forest. Native plants also do a better job of capturing rainwater.

It’s important to carefully continue to restore native plants to the land. One way to restore native plants is to introduce them into urban landscapes and parks where we can care for them and make sure they thrive. Living with native plants will also help people recognize and appreciate what makes the Hawaiian Islands a special place.