By Russell T. Nagata
By Russell T. Nagata
University of Hawaii at Manoa
College of Tropical Agriculture and Human Resources
Komohana Research and Extension Center-Hilo
For the tropical gardener in Hawaii, the European honey bee has been an important partner that insures proper pollination for many crops that we grow in our gardens. Early in human civilization, we mastered apiculture or the cultivation of bees, to better reap the benefits of bees.
Humans, mainly of European descent, have transported the European honey bee around the world to help pollinate crops and to provide honey and wax.
The kiawe, on the other hand, brings mixed feelings. To some, it’s an invasive species that takes over the shoreline on dry leeward coasts of all islands, blocking access and use. In addition, the sharp thorns on many trees are a safety issue, as they are able to pierce through bare skin, clothing and even thin footwear. (As a note, there are kiawe trees that do not have thorns.)
To others it provides just the right amount of dappled shade, not too bright and not too dark, for those hot days at the beach, park or in the garden. In addition, it is the cooking fuel of choice for many a grilling purist whether it’s kiawe logs and branches or kiawe charcoal. Whatever your feelings for the kiawe, it will forever be intertwined with the story of the honey bee and ranching in Hawaii and how each supported the others in its rise to prominence in the history of Hawaii.
The kiawe, Prosopis pallida, a native of Peru, was introduced into Hawaii in 1828 via the Royal Gardens in Paris, France, by Father Bachelot. The first trees were planted at the Catholic Mission on Fort Street in Honolulu and in little over a decade became a very common shade tree around the city. The kiawe grows best in dry, hot environments and can tolerate saline conditions which allow it to grow on the coastline nearly down to the waterline. The kiawe wood is very hard and resistant to rot and many trees were used as fence posts to hold barbed wire to fence in cattle and other animals.
The first successful introduction of the European honey bee, Apis mellifera, into Hawaii occurred in 1857 on the island of Oahu from California. Several prior introductions were unsuccessful due to the long transit over the Pacific Ocean that weakened the colony to the point where it did not survive upon reaching Hawaii. This was followed with several additional successful introductions of honey bees to the islands. During the following decades, most of the honey bee expansion in Hawaii occurred from swarm colonies breaking away from the original colonies.
Beginning in the 1890s, the cattle industry began to grow in Hawaii and with it brought the need for increased production of cattle forage and feed that could be grown in Hawaii. Along with grasses, kiawe seed pods were identified as an important food source for the cattle. Therefore, the kiawe was planted and encouraged to spread to provide food and shade for cattle roaming the dry, hot leeward side of the islands.
During this time, the honey bee had an instrumental role in the spread of kiawe in Hawaii. As a way to increase kiawe seed pod production, honey bee hives were placed in close proximity to kiawe trees to increase pollination of flowers and thereby increase the pod and seed set. This resulted in a quick and manyfold increase in the acreage of kiawe on the Big Island and the rest of the state. One of the upsides of all of the kiawe trees was the good quality of kiawe honey that was produced and exported to North America and Europe. At its height of production, more that 200,000 pounds of kiawe honey were exported annually from Hawaii.
Currently, the plight of the European honey bees in Hawaii has been well documented. The recent introduction of the small hive beetle and the varroa mite has had a devastating effect on hive survival and vitality. The overall reduction of bees, and subsequent loss of managed hives and feral colonies, has resulted in yield reductions of certain crops that are dependent on their pollination services. In addition to crop yield reductions, the two insect pests are also threatening the multi-million dollar queen bee production businesses that we have on the Big Island. Annually, several hundred thousand queen bees are exported from Hawaii.
For more information on this and other gardening topics, please visit the CTAHR electronic publication website at http://www.ctahr.hawaii.edu/Site/Info.aspx or visit any of the local Cooperative Extension Service offices around the island. I can be reached at russelln@hawaii.edu.