Planting Koa

Dr. J. B. Friday, CTAHR Extension Forester, joins Steve Coffee, Educational Solutions Inc. in an instructional video about how to outplant koa seedlings to maximize their survival. Filmed at Kaiholena, Ka'u, Hawai'i Island. Partial funding provided by USDA NRCS and USFS.

(June 2012)

Thinning, Fertilization and Herbicide Trials to improve Koa Production

Dr. J.B. Friday, CTAHR Extension Forester, explains a research trial to study the results of thinning, fertilization, and herbicides to improve Acacia koa production. Dr. James Leary, CTAHR Invasive Weed Specialist, explains the herbicide trial and demonstrates an application. CTAHR Virtual Field Day: Umikoa Ranch November 2008. ONE YEAR LATER follow-up shows the effect of the grass control. November 2009.

Efficiency of Incision Point Applications on Schinus terebinthifolius (Christmas berry)

Dr. James Leary, UH-CTAHR Invasive Weed Specialist, returns to the Kanaio Natural Area Reserve, Maui, to view the effects of incision point applications on Christmas berry (Schinus terebinthifolius) using triclopyr®, imazapyr®, and aminopyralid®. March 2010.

HBT™: Herbicide Ballistic Technology

Dr. James Leary, CTAHR Invasive Weed Specialist, introduces HBT™ to control invasive weeds in Hawaii. September 2008.

Herbicide Ballistic Technology™ for Miconia Control on Maui

Dr. James Leary, CTAHR Invasive Weed Specialist, interviews staff from Maui Invasive Species Committee (MISC) about their long-term efforts to control Miconia calvescens on Maui, and initiates field trials using herbicide ballistic technology (HBT™). May 2009.

A Case Study in Rapid Response:
Rauvolfia vomitoria

Big Island ranchers identified a new weed problem, Rauvolfia vomitoria, rapidly becoming a pest. Dr. James Leary, CTAHR Invasive Weed Specialist, conducted some herbicide field trials to attempt to quickly contain the infestation. This video describes the problem and shows the methods (broadcast application/spraying, frill and squirt) using triclopyr, imazapyr, and glyphosphate. February 2009.

Koa Forest in Koke'e:
Recovery and Threats

Koa Field Day by Dr. J. B. Friday, CTAHR Extension Forester, and Dr. Travis Idol, CTAHR Associate Professor of Tropical Forestry. A native koa forest that regenerated after hurrince 'Iwa and salvage logging in 1982 is now threatened by invasive species. Koke'e State Park, Kaua'i.

(June 2009)

Koa Regeneration: Hands-free Spraying for Koa Corridors

Dr. James Leary, UH-CTAHR, conducts herbicide trials at Hakalau Forest National Wildlife Refuge to help re-establish critical habitat with Acacia koa vegetative corridors. Leary demonstrates the use of a prototype hands-free backpack sprayer to safely apply herbicide in uneven terrain.

July 2008

Herbicide Trials on kikuyu grass at Volcano National Park

Dr. James Leary, CTAHR Invasive Weed Specialist, initiates herbicide field trials with staff from the National Park Service (NPS) on kikuyu grass (Pennisetum clandestinum) at Volcano National Park. Herbicides tested were: glyphosate and imazapyr. Two types of hands-free spraying systems are shown. Dr. Leary visits the site again and reports back on how the herbicides performed. August 2009.

Rapid Fire Targeting of Gorse with HBT™

Dr. James Leary, UH-CTAHR Invasive Weed Specialist, initiates an herbicide trial on the slopes of Mauna Kea, Hawaii Island, to evaluate the impact of HBT™ (Herbicide Ballistic Technology™) applications with triclopyr on gorse (Ulex europaeus). January 2010.

HBT™ Herbicide Ballistic Technology for Controlling Fountaingrass

Dr. James Leary, Invasive Weed Scientist at CTAHR partners with Ian Cole from the Hawaii Dept. of Land and Natural Resources (DLNR) Division of Forestry and Wildlife (DOFAW) to conduct herbicide trials to control invasive fountaingrass (Pennisetum setaceum) at Manuka Natural Area Reserve, Hawaii Island. January 2009.

RESULTS: Rauvolfia vomitoria 100 days later

Dr. James Leary, CTAHR Invasive Weed Specialist, observes the results of herbicide field trials to control a Rauvolfia vomitoria infestation on Hawaii Island 100 days later. This video describes the pros and cons of each treatment (broadcast application/spraying, frill and squirt) using triclopyr, imazapyr, and glyphosphate. February 2009.

Establishing Silvopastures with Acacia Koa

Dr. James Leary, CTAHR Invasive Weed Scientist, Dr. J. B. Friday, CTAHR Extension Forester, and Dr. Travis Idol, CTAHR Assistant Professor of Tropical Forestry, research an innovative approach to restoring koa corridors on pastureland in Hawaii for land management to support both cattle and koa production. Herbicide trials and scarification methods are examined (July 2009).

Grass Suppression for Koa Regeneration

Dr. James Leary, UH-CTAHR, conducts herbicide trials at the Kona Hema Reserve to control grasses suppressing regrowth of koa seedlings (Acacia koa) using glyphosate (Roundup®), fluazifop-p-butyl (Fusilade®), and imazapyr (Habitat®). Dr. Leary also demonstrated use of a hands-free spraying system and evaluates the impacts of imazapyr on other native species (ohia, Metrosideros polymorpha).

May 2009

Injection Methods for Controlling Albizia

Dr. James Leary, CTAHR Invasive Weed Specialist, conducts field trials at Maunawili Experiment Station, Oahu, targeting the invasive tree Albizia (Falcataria moluccana; syn. Albizia moluccana, Albizia falcata, Albizia falcataria, Adenanthera falcataria, Paraserianthes falcataria). Using Milestone® VM (active ingredient: aminopyralid), he researches two application methods: drill application vs. frill cut. October 2009.

HBT™ Results: Herbicide Ballistic Technology for Long Range Control of Invasive Weeds

Dr. James Leary, UH-CTAHR Invasive Weed Specialist, returns to Kaua'i to view the impact of HBT™ applications with imazapyr (Habitat®) on Australian tree fern (Sphaeropteris cooperi), kahili ginger (Hedychium gardnerianum), and basal bark applications to strawberry guava (Psidium cattleianum). March 2009.

HBT™ for Control of Photinia

Dr. James Leary, UH-CTAHR Invasive Weed Specialist, conducts HBT™ (herbicide ballistic technology) trials on Photinia davidiana. October 2008.

Herbicide Trials on meadow rice grass at Volcano National Park

Dr. James Leary, CTAHR Invasive Weed Specialist, follows up on herbicide trials to control meadow rice grass (Ehrharta stipoides) at Volcano National Park. Herbicides tested were: fluazifop-p-butyl, glyphosate, and imazapyr. August 2009.