Koa trees are among the largest native trees in Hawaii. They reach well over a 100 feet tall and can have thick trunks 10 feet in diameter. Their reddish brown hardwood is highly prized and is extremely valuable. As a result, koa trees have been over-harvested and very few big old koa trees exist in the wild today. The few large trees that can still be found today live in protected remote areas of the islands.
While koa trees are found in wet rainforests, they seem to prefer drier climates that receive less than 100 inches of rain a year and are often co-dominant with ohia trees. They are especially plentiful in the mesic forests of Kokee on Kauai.
This photo of Honopu Valley on the Na Pali Coast of Kauai shows a grove of koa trees in the foreground. Honopu Valley in one valley over from Kalalau Valley and can be reached from a trail within Kokee State Park.
This photo of the steep walls of Awaawapuhi Valley, was taken from a koa tree. You can clearly see that characteristic sickle shaped “leaves” of the koa tree. Koa trees are unique in that adult leaves are actually modified petioles or leaf stems.
This photo shows the juvenile leaves of a sapling in mid-tranformation into adult “leaves”. Juvenile leaves start out as a double row of pinnate leaves. As the sapling begins to mature its petioles (leaf stems) begin to widen into the sickle shaped blades that become adult “leaves”.
Tall straight koa trees were used in old Hawaii to make the voyaging canoes that sailed thousands of miles across the Pacific Ocean to the far corners of the Polynesian world to New Zealand and Easter Island. Unfortunately, only a handful of big tall straight koa trees remain today. Here is a photo of me standing beneath one of few living koa trees that could be hewn into a voyaging canoe. This specimen lives in The Nature Conservancy’s Kona Hema Preserve in Honomalino in South Kona.
Koa trees are also unique because they can sprawl and twist on the ground before sending up multiple trunks. In this photo taken in the Kapapala Forest Reserve on Mauna Loa, I climbed up the trunk of a thick koa tree some 6 feet thick to photograph the two trunks that grew out of both ends of the tree.
One of my favorite things to photograph are big old gnarled koa trees that have withstood the test of time. Their twists, scars and burls testify to fact they are survivors. This 5 foot thick koa tree is several hundred years old and grows along the Ainapo Trail that leads to the summit of Mauna Loa. It must have been toppled in the distant past by a hurricane or tropical storm. But it survived the assault and twisted itself back upright to create this distinctive shape.