Caterpillar pest earns name with way it hurts humans as well as plants

Kia‘i Moku By Joylynn Paman hotel display on Moloka’i. But in June of this year, the Do you nettle caterpillar was found have a at a nursery on O‘ahu and garden? just a few weeks later, was Kids discovered in lower Ha‘ikū who like on Maui. to run barefoot The voracious caterpillars outside? can significantly damage a Ever plant’s leaves and reduce gather ti leaves for a table the aesthetic and economic decoration or for cooking? value of ornamental and Maui’s latest invader may landscape plantings. The cramp your style thanks to caterpillars feed on over 45 the painful punch packed different species of plants, by the stinging nettle cater- including fishtail palms, pillar (Darna pallivitta). raphis palms, coconut, star- This rather small insect, fruit, ti, iris, most lilies, native to Asia, is only an several varieties of grasses, inch long, but if your skin and the endemic mamaki. makes contact with its Detecting the caterpillar is many rows of stinging, hard because it is so small. spiny hairs you might feel Adult moths are only ½ like you’ve been playing inch long. with fiberglass or run into a Portuguese man-of-war. The Hawai‘i Department The stinging nettle caterpillar is only an inch long but its many rows The spines release an irri- of Agriculture (HDOA) is of stinging, spiny hairs release an irritant that causes the skin to burn tant that causes the skin to now using pheromone traps and itch. The caterpillar also can damage a plant’s leaves burn and itch, for up to to try and learn just how significantly, and reduce the aesthetic and economic value of three weeks. If spines get far this pest has spread in ornamental and landscaping plantings. (Photos by HDOA) into the eyes or breathing the Ha‘ikū area. The hang- become difficult, immedi- ing traps have a sticky You can avoid transport- allow us to keep playing ate medical attention is board inside and use a ing host plants around the outside without worrying needed. pheromone or synthetic island. If you find a nettle about the next invader hormone to attract adult caterpillar or an adult moth that’s lurking in the grass. How did this pest get male moths. Traps have outside the Ha‘ikū area, here? First discovered on been placed in 33 one-mile call HDOA at 873-3555 or For more information the Big Island in 2001, the grids to determine the ex- the PEST Hotline at 643- about the stinging nettle nettle caterpillar probably tent of the infestation. The PEST. If your property be- caterpillar, check out the came in on plants from traps also help to control comes infested with the informative brochure from Taiwan. It then spread the adult moths, but the nettle caterpillar, plantings the University of Hawaii’s along the Big Island’s east- pheromone is not available can be moved away from College of Tropical Agri- ern side and by last year commercially. the home to reduce the risk culture and Human Re- was found in the Kona Dis- of getting stung. You can sources: trict and more recently in To help, you can learn use a bug zapper or spray www.ctahr.hawaii.edu/oc/f Köhala. Reports of stinging how to identify the nettle host plants with a commer- reepubs/pdf/IP-22.pdf. incidents began increasing caterpillar. Other caterpil- cially available insecticide. on the Big Island as more lars may have spines, but • “Kia‘i Moku”(or people came into contact don’t sting. For instance What does this mean for “Guarding the Island”) is with the caterpillars. Two our beautiful native Kame- Maui? The current surveys prepared by the Maui Inva- years ago, the caterpillars hameha butterfly, the will help establish what sive Species Committee to were found by a nursery painted lady, red admiral we’re up against. We don’t provide information on pro- owner on Maui in a ship- and American lady all have yet know whether the net- tecting the island from in- ment of plants from the Big caterpillars with spines. So tle caterpillar battle is win- vasive plants and animals Island, which were imme- be sure you have really nable. What we do know is that can threaten the is- diately shipped back. A found a nettle caterpillar that a stronger statewide land’s environment, econ- single caterpillar was de- before you go on the war and inter-island quarantine omy and quality of life. Joylynn Paman, is public tected and controlled in a path! system and better methods relations and education cut flower arrangement in a of early detection could specialist with the MISC.

As submitted to The Maui News. October 14, 2007. Page D8.