Restriction could support flower farming, keep pests at bay


The ohia lehua tree is the foundation of the Hawaiian forest. To protect the tree and the ecosystem it supports, the Hawaii Department of Agriculture is in the process of restricting imports of myrtle family plants as they may carry diseases that affect ohia. -- ESTELLA SNOWDEN / Maui Invasive Species Committee photo

In the spring of 2017, Dr. Cynthia Nazario-Leary, urban horticulture extension agent with UH College of Tropical Agriculture and Human Resources, was on a hunt. She was trying to determine which ornamental plants imported to the state posed the greatest risk of carrying pests and diseases and had come to visit the Hawaii Department of Agriculture’s inspection facility at the Kahului Airport. In its massive freezer, where confiscated pests go to die, she found boxes and boxes of hydrangea flowers. These cut flowers never reached their destination because they carried an insect not known to occur in our state. Ironically, hydrangea grow in many people’s yards, but local flower growers don’t produce them for florists.

By researching potential crops and connecting florists and growers, Nazario-Leary is doing the groundwork to support a field-to-vase movement — a floral take on the buy-local and farm-to-table movements that have become increasing popular in Hawaii. At the same time, HDOA is working to limit the amount of high-risk plant material coming into the state. Importing plant material is the most likely way for new plant pests and diseases to reach our shores; despite best efforts, some hitchhikers slip past the inspection process.

When these pests do arrive, the results can be devastating. In 2015, Puna residents started reporting the sudden die-off of ohia trees in their yards. Researchers on the Big Island linked their demise to two varieties of a vascular Ceratocystis fungus new to Hawaii. The disease, now known as Rapid Ohia Death, has affected at least 135,000 acres on Hawaii island, and small numbers of infected trees have also been detected on Kauai. Preventing these types of pathogens from arriving in the first place is essential.

To protect ohia, the foundation of our forest ecosystem, HDOA is in process of restricting the import of cut foliage and plants that belong to the myrtle family (myrtaceae). An earlier ban, in place from 2008 to 2012, was imposed in response to the discovery of a leaf fungus, Puccinia psidii, that nearly wiped out rose apple across the state. Local scientists raised the alarm that arrival of a more virulent strain could decimate ohia and also impact other plants in the same family, such as mountain apple, eucalyptus or bottle brush.

Nazario-Leary sees the myrtaceae ban as not just a tool to protect native ecosystems, but also a way to promote local industry. “This is an opportunity to utilize the things we have here, that are unique to Hawaii,” she says. In terms of floral design, she says, “It’s an opportunity to stand apart from other places in the world.”

Nazario-Leary is evaluating waxflower and tea tree, both myrtles, for their ease of growing and cut flower potential. The proposed ban will allow importation of surface-sterilized seeds and tissue-cultured plants, which can be used for import replacement efforts.

“We strive to eat local and buy local, and we should do that for flowers as well,” says Nazario-Leary.

When you are getting flowers, ask where they were grown and, whenever possible, support local flower growers just as you would local farmers. Hawaii is a place like no other. You can help protect it and promote local businesses. To read more about the proposed restriction or to find out how to share your thoughts about the rule, visit:

* Lissa Fox Strohecker is the public relations and education specialist for the Maui Invasive Species Committee. She holds a biological sciences degree from Montana State University. “Kia’i Moku,” “Guarding the Island,” is prepared by the Maui Invasive Species Committee to provide information on protecting the island from invasive plants and animals that can threaten the island’s environment, economy and quality of life.