‘Ohai (Sesbania tomentosa) – Keep it in a pot!

    

    If you have spent any time hiking in Hawai‘i, you know how beautiful an ‘ōhi‘a lehua is in full bloom, or a towering koa with the sunlight flickering through its sickle-shaped leaves. Why then are the roadsides and parks of Honolulu devoid of these native Hawaiian trees? Likewise, the inflorescence of a Hawaiian Trematolobelia is breathtaking, and, yet, these amazing plants are absent from our front yards and gardens. Why? Coffee table and textbooks would have you believe the greatest threats to Hawai‘i’s native flora are habitat destruction, introduced herbivores like cattle, goats and pigs, highly competitive alien plants, and, most recently, climate change. But which of these explains why we do not see a long row of ‘ahakea shading the cars on Kalakaua Avenue? The truth is we have made the soil in our cities, neighborhoods, and front yards lethal to these and many other native Hawaiian plants with the introduction, over decades, of deadly alien bacteria and fungi and injurious microscopic animals like root-knot nematodes. Unfortunately, the 2018 identification of two species of Ceratocystis, the fungi responsible for the Rapid ʻŌhiʻa Death now threatening to destroy entire native Hawaiian forests, may be the event that finally awakens us to this long-ignored invisible invasion.