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Makawao, HI, United States

Leary J.J.K.,University of Hawaii at Manoa | Gooding J.,National Park Service | Chapman J.,Kauai Invasive Species Committee | Radford A.,Maui Invasive Species Committee | And 2 more authors.
Invasive Plant Science and Management | Year: 2013

Miconia (Miconia calvescens DC.) is a tropical tree species from South and Central America that is a highly invasive colonizer of Hawaii's forested watersheds. Elimination of satellite populations is critical to an effective containment strategy, but extreme topography limits accessibility to remote populations by helicopter operations only. Herbicide Ballistic Technology (HBT) is a novel weed control tool designed to pneumatically deliver encapsulated herbicide projectiles. It is capable of accurately treating miconia satellites within a 30 m range in either horizontal or vertical trajectories. Efficacy was examined for the encapsulated herbicide projectiles, each containing 199.4 mg ae triclopyr, when applied to miconia in 5-unit increments. Experimental calibrations of the HBT platform were recorded on a Hughes 500-D helicopter while conducting surveillance operations from November 2010 through October 2011 on the islands of Maui and Kauai. Search efficiency (min ha-1; n = 13, R2 = 0.933, P< 0.001) and target acquisition rate (plants hr-1, n = 13, R2 = 0.926, P< 0.001) displayed positive linear and logarithmic relationships, respectively, to plant target density. The search efficiency equation estimated target acquisition time at 25.1 sec and a minimum surveillance rate of 67.8 s ha-1 when no targets were detected. The maximum target acquisition rate for the HBT platform was estimated at 143 targets hr-1. An average mortality factor of 0.542 was derived from the product of detection efficacy (0.560) and operational treatment efficacy (0.972) in overlapping buffer areas generated from repeated flight segments (n = 5). This population reduction value was used in simulation models to estimate the expected costs for one- and multi-year satellite population control strategies for qualifying options in cost optimization and risk aversion. This is a first report on the performance of an HBT helicopter platform demonstrating the capability for immediate, rapid-response control of new satellite plant detections, while conducting aerial surveillance of incipient miconia populations. © 2013 Weed Science Society of America. Source

Rodriguez R.,University of Hawaii at Manoa | Leary J.J.K.,University of Hawaii at Manoa | Jenkins D.M.,University of Hawaii at Manoa | Mahnken B.V.,Maui Invasive Species Committee
American Society of Agricultural and Biological Engineers Annual International Meeting 2015 | Year: 2015

Since 2012, the Herbicide Ballistic Technology (HBT) platform has been deployed in helicopter operations with a mission to eliminate nascent populations of the invasive plant species Miconia (Miconia calvescens DC) spreading across the East Maui Watershed (Hawaii, USA). The HBT platform is a refined pesticide application system that pneumatically delivers encapsulated, herbicide projectiles (i.e., paintballs) from long range (up to ~30m) and varying attitude. This onboard system provides accurate, effective treatment of individual plant targets occupying remote, inaccessible portions of the forested landscape. Statistics in operational performance are accomplished through GIS analyses of recorded GPS data assigned to treated plant targets. Recently, we have developed a telemetry system for HBT applications (HBT-TS) to enhance the attribute data of a target treatment. The HBT-TS integrates a hardware sensor device with the electro- pneumatic marker that is actuated by the trigger to generate time stamped, geo-referenced attribute data including, (i) target assignment, (ii) azimuth, (iii) tilt and (iv) range determined from the applicator position, for every projectile discharged. With target assignments, the HBT-TS records the exact dose applied to each target. Furthermore, the timestamps show that actual time to administer projectiles (i.e., target treatment) is a minor component of the total time on target. By tracking the orientation and distance of the discharged projectile, we are able to calculate a precise offset target location relative to the applicator position and provide a high-resolution interpretation of herbicide use rate (grams acid equivalents ha1) based on the known amount of herbicide contained in each projectile and the final placement on the landscape. We acknowledge the challenges of GPS inaccuracies while recording in a dynamic environment (i.e., a moving platform in extreme topography), albeit with increased precision. Regardless, the current state of the HBT-TS technology enhances operational intelligence relevant to landscape scale invasive species management. Copyright © (2015) by the American Society of Agricultural & Biological Engineers All rights reserved. Source

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