Why Tree Improvement

Advances in Acacia koa (koa) silviculture and breeding can make reforestation with this important native species more attractive to land owners and managers. Ultimately, this could enable large areas of deforested land to be restored, providing economic, ecological, and cultural benefits to Hawaii. Improved varieties of Acacia koa will help in the conservation of this valuable species, making it an attractive alternative to non-native tree plantations, cattle ranching, or other land uses that do not provide the benefits that of native forests.

The tree improvement program we are developing is based on selective breeding, a procedure that has been practiced since the development of agriculture by ancient civilizations. We use morphology and performance from common garden and greenhouse trials to select the top performing trees. We then collect seeds or use other methods to propagate the selected trees to advance in the improvement program. The best trees are planted in seed orchards to provide a ready supply of improved seed.

The initial goals of the TropHTIRC improvement program are to understand the genetic variability of koa, develop silvicultural practices that will increase planting success, and establish seed orchards for improved trees. Although koa has been researched for many years, major knowledge gaps remain in understanding its biology and ecology. In particular, little is known of its phenology and pollination patterns. Our research will advance knowledge of koa biology and ecology, and the relationships between gene expression, environmental conditions, and performance.

We are working closely with landowners and major stakeholders to ensure that our research and extension activities are focused on meeting their needs. In the future, we will expand the improvement program to other species within the Pacific Islands. We are open to new collaborations and encourage you to contact us if you are interested in participating.