Hawaiian Forests

Biological control of weeds in Hawaiian forests

Tracy Johnson Research Entomologist

Strawberry Himalayan guava Miconia Tibouchina raspberry Biocontrol introductions in Hawaii, 1900-1995

Parasitoids 50 Predators Herbivores 40

0 0s 10s 20s 30s 40s 50s 60s 70s 80s 90s Decade Follett et al., 2000 (Source: Hawaii Dept. of Agriculture) Target selection / Support for forest weed biocontrol in Hawaii

Biocontrol Steering Committee: USDA Forest Service Active in biocontrol research National Park Service targeting native forest weeds Hawaii Dept. of Land and Natural Resources USGS Biological Resources Division US Fish and Wildlife Service The Nature Conservancy Hawaii Dept. of Agriculture Active in biocontrol research University of Hawaii (agricultural focus) USDA APHIS ….. USDA ARS Kamehameha Schools Dept. of Hawaiian Homelands US Dept. of Defense Hawaii Dept. of Health Ecological expertise: tropical forest restoration invasive plant species tropical wetlands forest management services

USDA Forest Service Institute of Pacific Islands Forestry Hilo, Hawaii Target Learning to just weeds say no Strawberry Banana Clidemia guava poka

not right now Miconia Cape ivy Tibouchina

maybe when later resources Christmas Himalayan allow berry raspberry Fayatree Miconia in Tahiti since 1937 in Hawaii since 1959

Colletotrichum biocontrol introduced 1997 Aerial herbicide treatment of miconia infestation costs > $1 million annually

Photos: Maui Invasive Species Committee Biocontrol of Miconia calvescens

Evaluating potential agents from Costa Rica and Brazil Anthonomus Leaf, stem and fruit feeding insects monostigma

Cryptorhynchus melastomae Atomacera spp.

Diclidophlebia lucens

Euselasia chrysippe Mompha sp. Not all green is good: Strawberry guava spreads like cancer in Hawaii’s native forests

Remote sensing by Carnegie Airborne Observatory Strawberry Guava in Brazil Detailed studies 1991-2005

Gall forming insect Tectococcus ovatus selected as most effective natural enemy Biocontrol of weeds Top targets in conservation areas Miconia Strawberry guava Kahili ginger

Hedychium gardnerianum Clidemia hirta Tibouchina and other melastomes Christmasberry (Schinus terebinthifolius) Fayatree (Morella [Myrica] faya) Albizia (Falcataria moluccana) Rubus spp. Bocconia frutescens Fountain grass (Pennisetum setaceum) Biocontrol of Tibouchina herbacea

Quarantine studies: flea beetle from Brazil is specific to melastomes (Tibouchina, Pterolepis, Melastoma)

Syphraea uberabensis adults and larvae defoliate plants Biocontrol of Himalayan raspberry (Rubus ellipticus)

Chinese collaborators searching for agents specific to target that will not attack native Hawaiian Rubus Clidemia in Costa Rica with nematode galls Clidemia with nematode galls (Ditylenchus gallaeformis) Biological control of Hawaiian forest weeds Release & Monitor Tectococcus

Tibouchina agent Quarantine Testing Miconia agent Rubus in China Foreign

Exploration Bocconia in Costa Rica

Target

Selection Strawberry Himalayan guava Miconia Tibouchina raspberry Bocconia Stem boring weevil Cryptorhynchus melastomae

Feeding by adults

Egg laid in stem

Adult Brazil

Common guava

Strawberry guava

Tectococcus survives only on strawberry guava