"Haole Koa" Leadtree-Leucaena leucocephala
4 things you may not know about this Kauai plant
1. What is it? Haole Koa is the Hawaiian name of the Leadtree. It is a member of the Pea family. It is a perennial evergreen tree or shrub. This plant can grow up to 20' or more and can be seen at all different heights from shrub to tree . It's leaves are bipinnate and mimic a Mimosa leaves but smaller. There are similarities to the Hawaiian Koa native-flowers are both round with the Haole Koa being a white ball and the Koa flower is a yellow ball and the leaf of young Koa plants looks a lot like bipinnate one of the Haole Koa. The Leadtree flowers are loved by bees and I read that pollen gathered from them, is one of the flavors making up winter honey produced on Maui. The seed pods are flat starting green and turning brown as they mature and grow in clusters of 15-60. The seed reminds me of a flattened apple seed and each pod has 15-25 of them. The Haole Koa is easily seen along the roads and paths all over the Islands.
2. Where did it come from? The Leadtree is native to the Eastern part of Mexico and Central America but has been introduced and naturalized in other tropical islands as well as in Florida and Texas. The first plants arrived here in the late 1800's and the seeds possibly were broadcast by planes. They were known in Hawaiian as “Haole Koa” or “Koa Haole” meaning “foreign Koa.”. Although very weedy, does have a number of uses, which is why it was deliberately planted here. These fast-growing trees have been used for erosion control and as shade for coffee plantations. They have naturalized here because of their tolerance to drought, poor soil, and salt. This legume can also be used as green manure because it helps fix nitrogen in soil and enriches it. The foliage has been used as animal fodder and forage for sheep, goats and cattle but in limited amounts. The wood can be used for firewood or for making charcoal. The pods and seeds can be eaten by humans but have to be cooked to make them non-poisonous. There is a chemical compound found in the pods and seeds which can cause hair loss so I have opted to forego eating them and just using them for decorative purposes.
3. When is the best time for collecting? This plant flowers and fruits all year long. I collect the pods only, and wait until they are brown. I like to pick the ones which have recently turned brown for a more vibrant and creamy interior color. They store well and I have not had any problems with mold, bugs or change of color.
4. How are the collected plant parts used? I use the pods on our baskets, pouches and on several styles of our Christmas Angels. I have also strung some of the seeds for a lei and discovered that by boiling them 5-10 minutes, I didn’t need to drill them, just use a needle.
*Amy is a University of Hawaii Certified Master Gardener Emeritus, has a Bachelor of Science-Landscape Horticulture degree from Ohio State, has been a volunteer tour guide at NTBG, and is a self-proclaimed "plant nut"! She and her husband Ron have been making and selling their baskets for more than 20 years.