Vegetation Management Programs Research Articles

Resource optimization and image processing for vegetation management programs in power distribution networks

Vegetation management programs are some of the largest budget items for utility companies in their efforts to prevent power outages. Our work focuses on developing techniques to streamline vegetation management operations through detection of at-risk locations in a power distribution network. We have trained deep convolutional neural networks to segment vegetation and estimate the risk of outage using high resolution aerial imagery. The output of these networks helps in the optimization of resource allocation and vegetation management planning. Experimental results on the Bay Area Synthetic Network demonstrate high accuracy in segmentation and risk prediction, thus minimizing costs for vegetation management programs.

Phytotoxic Effects of Acetic Acid and d-limonene on Four Aquatic Plants

Herbicides that are labeled for aquatic use are often the foundation of aquatic vegetation management programs in the United States because many of these products, which are registered by the U.S. Environmental Protection Agency, are effective, selective, and relatively inexpensive. Resource managers are interested in reducing the use of synthetic herbicides and are considering alternative methods for aquatic weed control. We evaluated the effects of acetic acid and d-limonene on growth of the invasive small floating species feathered mosquitofern (Azolla pinnata) and common salvinia (Salvinia minima), as well as on the native emergent wetland plants cattail (Typha latifolia) and gulf coast spikerush (Eleocharis cellulosa). Acetic acid and d-limonene (alone and in combination) were applied once as foliar treatments to healthy plants, which were grown for 8 weeks after treatment to allow for development of phytotoxicity symptoms. All experiments also included diquat dibromide at three concentrations as “industry-standard” treatments for comparison. A 0.22% concentration of diquat dibromide eliminated all vegetation of all species. Most single-product treatments provided good control of invasive feathered mosquitofern with acceptable levels of damage to native gulf coast spikerush, but only 15% and 20% d-limonene treatments were effective on invasive common salvinia and selective for native cattail. Some combinations of acetic acid and d-limonene provided acceptable control of both floating weeds and selectivity for gulf coast spikerush, but all mixes caused unacceptable levels of damage to cattail. Treating these small floating weeds with acetic acid and d-limonene instead of diquat dibromide would increase material costs by 15- to 27-fold. Although these natural products may be useful in some areas where synthetic herbicides are discouraged, they are unlikely to be affordable options for most resource managers.

Quantifying Leaf Trait Covariations and Their Relationships with Plant Adaptation Strategies along an Aridity Gradient.

Simple SummaryPlants usually adopt different strategies to adapt to their surrounding environments. Accurately quantifying plant strategies is of great interest in trait-based ecology, in particular to understand the responses of ecological structures and processes. In the last two decades, these strategies have been described qualitatively; however, the use of quantitative methods is still lacking. In this study, we used a plant functional trait approach to discuss plant strategies along an aridity gradient. We found that eight functional traits divided into four dimensions represent four adaptation strategies: energy balance, resource acquisition, resource investment and water use efficiency. We also concluded that climate and soil together with family (vegetation succession) were the main driving forces of trait covariations. Our study provided a new perspective to understand plant functional responses to aridity gradients, which is helpful for ecological management and vegetation restoration programs in arid regions.A trait-based approach is an effective way to quantify plant adaptation strategies in response to changing environments. Single trait variations have been well depicted before; however, multi-trait covariations and their roles in shaping plant adaptation strategies along aridity gradients remain unclear. The purpose of this study was to reveal multi-trait covariation characteristics, their controls and their relevance to plant adaptation strategies. Using eight relevant plant functional traits and multivariate statistical approaches, we found the following: (1) the eight studied traits show evident covariation characteristics and could be grouped into four functional dimensions linked to plant strategies, namely energy balance, resource acquisition, resource investment and water use efficiency; (2) leaf area (LA) together with traits related to the leaf economic spectrum, including leaf nitrogen content per area (Narea), leaf nitrogen per mass (Nmass) and leaf dry mass per area (LMA), covaried along the aridity gradient (represented by the moisture index, MI) and dominated the trait–environmental change axis; (3) together, climate, soil and family can explain 50.4% of trait covariations; thus, vegetation succession along the aridity gradient cannot be neglected in trait covariations. Our findings provide novel perspectives toward a better understanding of plant adaptations to arid conditions and serve as a reference for vegetation restoration and management programs in arid regions.

Trade-Offs among Release Treatments in Jack Pine Plantations: Twenty-Five Year Responses

We assessed 27 indicators of plant diversity, stand yield and individual crop tree responses 25 years post-treatment to determine long-term trade-offs among conifer release treatments in boreal and sub-boreal forests. This research addresses the lack of longer-term data needed by forest managers to implement more integrated vegetation management programs, supporting more informed decisions about release treatment choice. Four treatments (untreated control, motor-manual brushsaw, single aerial spray, and complete competition removal) were established at two jack pine (Pinus banksiana Lamb.) sites in Ontario, Canada. Our results suggest that plant diversity and productivity in boreal jack pine forests are significantly influenced by vegetation management treatments. Overall, release treatments did not cause a loss of diversity but benefitted stand-scale yield and individual crop tree growth, with maximum benefits occurring in more intensive release treatments. However, none of the treatments maximized all 27 indicators studied; thus, forest managers are faced with trade-offs when choosing treatments. Research on longer term effects, ideally through at least one rotation, is essential to fully understand outcomes of different vegetation management on forest diversity, stand yield, and individual crop tree responses.

Establishing targeted control of creeping perennial weeds with soil‐active chemical injections: Assessment of subterranean bud responses in contact

AbstractIncreased infestation of aggressive creeping perennial weeds is a significant problem in urban vegetation management programs. These weeds produce vigorous biomass and extensive underground networks of either rhizomes or creeping roots that easily regrow from numerous buds. Foliar application of proper systemic herbicides has been a most effective way to suppress regrowth from underground creeping organs; however, killing the mature plants has disadvantages from aesthetic, economic, and ecological viewpoints. Therefore, we intended to test the possibility of soil‐injection of soil‐active herbicides for effective control of the perennial weeds which develop underground network systems. A pot experiment using combinations of seven species (seven rhizomatous and two having creeping roots) and five chemicals (four herbicides and a plant growth regulator) was conducted to assess whether and how chemicals diffused in soil affect the sprout and growth of buds on creeping organs. All the tested herbicides completely inhibited bud sprouting in one and more species when applied at median or high rates, while most of the flurprimidol‐applied segments sprouted but shoot elongation was significantly reduced. Characteristics of each herbicide were also reflected in the selectivity and features of new outgrowth. The results indicated that chemicals existing in soil were undoubtedly absorbed and affected bud activities. It is concluded that soil injection that delivers the probable soil‐active chemicals to subterranean creeping systems could be a promising technology for controlling noxious creeping perennials.

The elusive search for an effective repellent against voles: an assessment of anthraquinone for citrus crops

Vole (Cricetidae) girdling of tree trunks is a common form of damage experienced by tree and vine growers throughout much of the Northern Hemisphere. Management programs that effectively incorporate chemical repellents and vegetation management would be of substantial assistance to growers that experience such damage. Anthraquinone has proven effective as a repellent against voles in lab trials, yet controlled field tests of combined anthraquinone and vegetation management programs are lacking. Therefore, we established a mesocosm-based study in central California, USA, to test the efficacy of anthraquinone and vegetation management for reducing girdling damage caused by California voles Microtus californicus to Clementine citrus trees Citrus clementine under semi-field conditions. We observed a 90–100% reduction in girdling damage for trees following a single application of anthraquinone during two trials in summer and spring, respectively. Removal of vegetation around the base of trees further reduced damage during the summer sampling period, with no girdling observed on anthraquinone-treated trees that were surrounded by bare soil. We did not observe this same relationship during spring, and we observed no relationship between vegetation management in the absence of anthraquinone treatments in either seasonal trial, suggesting that vegetation management had a lesser impact on vole girdling than anthraquinone applications. We observed no decrease in efficacy of anthraquinone across the duration of both sampling periods (5–6 weeks), indicating substantial longevity for anthraquinone. Anthraquinone appears to have substantial utility for minimizing vole girdling damage. Field testing is warranted for additional mammalian species to determine potential uses for other taxa.

Early Vegetation Responses to Eight Right-of-Way Integrated Vegetation Management Techniques in Northern Canada

Integrated vegetation management programs have successfully reduced the frequency and intensity of power line right-of-way management by promoting low-growing plant communities resistant to tree invasion. To examine whether these principles are transferable to northern ecosystems, researchers tested eight treatments at four sites in Yukon, Canada. Two herbicides, imazapyr and triclopyr, were applied by three methods, as well as a native grass seeding treatment and a mowing control. Vegetation cover was recorded prior to treatment and after one year along with herbicide damage assessments. Overall, treatments caused significant changes to vascular plant communities after one year. Short-term control of woody target species was greater in chemically-treated plots (66%–94%) than with mechanical methods (<55%). All treatments caused a minor reduction in non-target vegetation cover. In seeded plots, seedlings emerged but total non-target species cover was reduced by seedbed preparation. Triclopyr broadcast spray reduced non-target vegetation cover by <10%, but the common shrub, kinnickinnick (Arctostaphylos uva-ursi), was highly impacted. Selective application of triclopyr effectively controlled targets with minimal effects on non-target species. Imazapyr consistently caused more impacts to non-target plants than triclopyr. Both selective and non-selective imazapyr applications resulted in chlorosis, stunting, and deformity of shrubs and forbs one year after treatment. This suggests imazapyr can remain active in northern soils for at least 365 days as well as transfer to untreated plants. The range of sensitivities of boreal plant species to imazapyr and triclopyr and potential persistence in northern soils highlights the need for focused toxicity research in the North.

Application of land-use management scenarios to mitigate desertification risk in northern Iran

The environmentally sensitive areas (ESAs) model has been applied to evaluate the risk of desertification in the Chehel-Chai Watershed, northern Iran. This research is mainly conducted to quantify and assess the effect of land-use change processes on desertification risk in areas with humid climate. Water erosion, soil, vegetation, climate and management practices were used as five main criteria for desertification mapping in this study. The degree of sensitivity to desertification was determined for each land unit using the categorization table of desertification intensity. For providing insights into optimal management programs, the desertification sensitivity map was used to analyze different scenarios of management strategies. By assuming that other indices are constant, these scenarios were replaced by altering land-use intensity parameter. Based on five above-mentioned criteria, the mean weight of quantitative value for desertification sensitivity was calculated, which was 1.32 for the research location. By comparing this value to ESAs table, the desertification class of the study area was determined as fragile (type 2). Scenario analysis results indicated that the relative frequencies of areas with critical states of desertification (i.e., classes 1, 2 and 3) are reduced by 18.84 and 14.27% in vegetation management scenario and land ecological capability evaluation scenario, respectively. Results of this study also highlighted that scenario maps are efficient tools for analyzing and identifying areas at high risk of desertification in Chehel-Chai Watershed, where desertification process could be alleviated if appropriate land-use planning and vegetation management programs are adopted.

Can anthropic fires affect epigaeic and hypogaeic Cerrado ant (Hymenoptera: Formicidae) communities in the same way?

Fire occurrences are a common perturbation in Cerrado ecosystems, and may differently impact the local biodiversity. Arthropods are one of the taxa affected by fires, and among them, ants are known as good bioindicators. We aimed to evaluate the effect of anthropic fires on epigaeic and hypogaeic ant communities (species richness and composition) in Cerrado areas with different post-fire event recovery periods. We conducted the study in four Cerrado areas during two weeks of 2012 dry season: one unburned and three at different post-fire times (one month, one and two years). We sampled ants with pitfall traps in epigaeic and hypogaeic microhabitats. We collected 71 ant morpho-species from 25 genera. In the epigaeic microhabitat we sampled 56 morpho-species and 42 in the hypogaeic microhabitat. The area with the shortest recovery time presented lower epigaeic ant species richness (4.3 ± 2.00) in comparison to the other areas (8.1 ± 2.68 species on one year area; 10.3 ± 2.66 species on two years area; 10.4 ± 2.31 species on control area), but recovery time did not affect hypogaeic ant species richness. Regarding ant species composition, fire did not directly affect hypogaeic ant species, which remained the same even one month after fire event. However, two years were not enough to reestablish ant species composition in both microhabitats in relation to our control group samples. Our study is the first to assess anthropic fire effects upon epigaeic and hypogaeic ants communities; highlighting the importance of evaluating different microhabitats, to more accurately detect the effects of anthropic disturbances in biological communities. We concluded that ant communities are just partially affected by fire occurrences, and epigaeic assemblages are the most affected ones in comparison to hypogaeic ants. Furthermore the study provides knowledge to aid in the creation of vegetation management programs that allow Cerrado conservation.

Performance of Sheep and Goats Fed Arctostaphylos canescens With and Without Polyethylene Glycol Supplementation

Abstract Arctostaphylos canescens Eastw. is considered an important element in the chaparral fire matrix and an invasive plant in coniferous forest plantations in California. Previous studies reported that dry matter intake of Arctostaphylos was low, presumably because of its low nutritional quality and high condensed tannin (CT) content. We hypothesized that intake and digestibility of Arctostaphylos could be increased by the provision of a tannin-complexing agent polyethylene glycol (PEG). This study determined the effects of PEG (MW 4000) supplementation on intake (I) and digestibility (D) of Arctostaphylos in goats and sheep. Polyethylene glycol was added to drinking water at four levels (0.3%, 0.15%, 0.05%, and 0%) of body weight (BW). Alfalfa pellets were used as diet supplement at 1.5% of BW. Nutritional quality of Arctostaphylos was low as compared with alfalfa pellets. Arctostaphylos crude protein (CP) levels were low (4.5% vs. 17.9%) and CT concentration was high (23.1% vs. 0%), whereas estimates of in vitro organic matter digestibility (OMD, 36.6%) and metabolizable energy (5.1 MJ · kg −1 dry matter [DM]) in Arctostaphylos were almost half of those found for alfalfa pellets (70.3% and 9.5 MJ · kg −1 DM). A curvilinear increase ( P −1 and per kg BW 0.75 ) was observed in goats and sheep as PEG levels increased, although a linear increase ( P −1 ) of Arctostaphylos by goats. Addition of PEG curvilinearly increased ( P P Arctostaphylos. However, the success in adopting this practice as a useful tool in vegetation management programs will depend on the cost–benefit ratio.

Performance of Mechanical Forest Vegetation Clearing Technique and Litter Decomposition

A mechanical technique for forest vegetation treatment is presented and analysed. A brush-cutting machine was used with Mediterranean-type vegetation in a forest vegetation management program to enhance wildlife habitat by promoting vegetation resprouting and grass reestablishment in mature shrublands. The performance of working time components was evaluated. Equipment components are described as well as benefits and applications of the technique. Two sites were compared in terms of vegetation composition and biomass, mechanical working performance, and litter decomposition rates. Litter decomposition was followed over a 2-year period. Changes in litter mass and nutrient content through time are evaluated and discussed. A working productivity between 3 and 4 h.ha-1 was obtained for different site and vegetation conditions. A major reduction of litter dry mass happens in the first 6 month after vegetation cutting. Litter decomposition rates range from -0.32 to -0.14 year-1 and the time for total decomposition ranges between 4 to 6 years. Litter nutrient composition presents the following order N>Ca>K>Mg>P. The relative mobility of these nutrients follows the order N>K>Ca>Mg>P. The estimated annual nutrient net release is about 91.8 kg N.ha-1, 4.5 kg P.ha-1, 52.8 kg K.ha-1, 39.5 kg Ca.ha-1 and 13.7 kg Mg.ha-1. Different litter decomposition rates and nutrient release on both sites and are discussed.

Use of Hyperspectral Remote Sensing to Evaluate Efficacy of Aquatic Plant Management

AbstractInvasive aquatic weeds negatively affect biodiversity, fluvial dynamics, water quality, and water storage and conveyance for a variety of human resource demands. In California's Sacramento–San Joaquin River Delta, one submersed species—Brazilian egeria—and one floating species—waterhyacinth—are actively managed to maintain navigable waterways. We monitored the spatial and temporal dynamics of these species and their communities in the Sacramento-San Joaquin River Delta using airborne hyperspectral data and assessed the effect of herbicide treatments used to manage these species from 2003 to 2007. Each year, submersed aquatic plant species occupied about 12% of the surface area of the Delta in early summer and floating invasive plant species occupied 2 to 3%. Since 2003, the coverage of submersed aquatic plants expanded about 500 ha, whereas the coverage of waterhyacinth was reduced. Although local treatments have reduced the coverage of submersed aquatic plants, Delta-wide cover has not been significantly reduced. Locally, multiyear treatments could decrease submersed aquatic plants spread, given that no residual plants outside the treated area were present. In contrast, the spread of waterhyacinth either has been constant or has decreased over time. These results show that (1) the objectives of theEgeria densaControl Program (EDCP) have been hindered until 2007 by restrictions imposed on the timing of herbicide applications; (2) submersed aquatic plants appeared to function as ecosystem engineers by enabling spread to adjacent areas typically subject to scouring action; (3) repeated herbicide treatment of waterhyacinth has resulted in control of the spread of this species, which also appears to have facilitated the spread of waterprimrose and floating pennywort. These results suggest that management of the Delta aquatic macrophytes may benefit by an ecosystem-level implementation of an Integrated Delta Vegetation Management and Monitoring Program, rather than targeting only two problematic species.

Control of Invasive Weeds with Prescribed Burning

Prescribed burning has primarily been used as a tool for the control of invasive late-season annual broadleaf and grass species, particularly yellow starthistle, medusahead, barb goatgrass, and several bromes. However, timely burning of a few invasive biennial broadleaves (e.g., sweetclover and garlic mustard), perennial grasses (e.g., bluegrasses and smooth brome), and woody species (e.g., brooms and Chinese tallow tree) also has been successful. In many cases, the effectiveness of prescribed burning can be enhanced when incorporated into an integrated vegetation management program. Although there are some excellent examples of successful use of prescribed burning for the control of invasive species, a limited number of species have been evaluated. In addition, few studies have measured the impact of prescribed burning on the long-term changes in plant communities, impacts to endangered plant species, effects on wildlife and insect populations, and alterations in soil biology, including nutrition, mycorrhizae, and hydrology. In this review, we evaluate the current state of knowledge on prescribed burning as a tool for invasive weed management.

Analysing initial attack on wildland fires using stochastic simulation

Stochastic simulation models of initial attack on wildland fire can be designed to reflect the complexity of the environmental, administrative, and institutional context in which wildland fire protection agencies operate, but such complexity may come at the cost of a considerable investment in data acquisition and management. This cost may be well justified when it allows for analysis of a wider spectrum of operational problems in wildland fire protection planning. The California Fire Economics Simulator version 2 (CFES2), is a sophisticated stochastic simulation model designed to facilitate quantitative analysis of the potential effects of changes in many key components of most wildland fire systems, e.g. availability and stationing of resources, dispatch rules, criteria for setting fire dispatch level, staff schedules, and deployment and line-building tactics. The CFES2 model can also be used to support strategic planning with respect to vegetation management programs, development at the wildland–urban interface, reallocation of responsibilities among fire protection agencies, and climatic change. The analytical capacity of stochastic simulations models to address such key issues is demonstrated using the CFES2 model in four case studies addressing the impact on initial attack effectiveness of: (1) multiple fire starts; (2) diversion of firefighting resources to structure protection; (3) alternate stationing of firefighting resources; and (4) multi-agency cooperation.

Vegetation Management Options in Almond Orchards

A well maintained orchard floor is critical for insuring year-round orchard access and a clean almond harvest operation. This study compared three methods of orchard floor vegetation management over a 4-year period. The objective of this study was to evaluate cost effective vegetation management programs for difficult to control summer annual weeds while maintaining the population of desirable winter annual species. Common purslane (Portulaca oleracea) can be a major summer weed problem that interferes with almond harvesting operations. A low rate residual herbicide program controlled purslane more consistently than mechanical or chemical mowing programs. Desirable winter weed cover was preserved in all three management systems. The costs for each program were similar; however, there was a reduction in the number of operations required for both chemical mowing and low rate residual programs compared to the mechanical mowing program.

Vegetation Management along Transmission Utility Lines in the United States and Canada

A survey investigating vegetation control methods along transmission rights-of-way was sent to 220 Utility Arborist Association companies. The survey contained questions regarding right-of-way characteristics, control methods used, total dollars spent on vegetation management, and priorities of the vegetation management program. The ROW area reported represented over 48% of all the investor-owned ROWs over 39 Kv in service throughout the United States. More than 75% of the respondents reported using herbicides on their rights-of-way. However, acres treated mechanically outnumbered those treated chemically by a margin of 2.7:1. Garlon 3A and Garlon 4 topped all herbicides, with a combined 220,574 projected gal (834,961 L) of the estimated 549,869 gal (2,081,474 L) of herbicide applied to transmission rightsof- way in 1995. It appears that quite low levels of active ingredients are being applied per acre. Basal, high-volume foliar, and low-volume foliar with a backpack or handgun applications accounted for approximately 75% of the acres of transmission ROWs treated with herbicides.

Public perceptions of risk and acceptability of forest vegetation management alternatives in Ontario

We examined public perceptions of risk and acceptability for 9 alternatives to controlling forest vegetation in Ontario (N = 2,301) in the fall of 1994. The proportion of respondents indicating whether an alternative was 1) difficult to control, 2) potentially catastrophic, 3) a problem for future generations, and 4) a personal worry determined perceptions of risk for each vegetation management alternative. Ranking of alternatives from highest to lowest perceived risk was: aerially-applied herbicides > biological control > ground-applied herbicides > mulches > prescribed fire > heavy equipment > cover cropping > manual cutting > grazing animals. Public acceptance was lowest for aerially-applied herbicides (18%) followed by ground-applied herbicides (37%), biological control (57%), prescribed fire (57%), mulches (65%), heavy equipment (72%), cover cropping (80%), grazing animals (82%), and manual cutting (89%). Public acceptability of various agents for biological control differed depending on the proposed agent. Natural plant toxins were viewed as most acceptable (73%) followed by microorganims (42%), genetically-engineered organisms (39%), and viruses (21%). We found a strong correlation between a risk perception index and acceptability of the alternatives for the general public (r2 = 0.84) and those in timber-dependent communities (r2 = 0.89). Our results suggest that stronger public support can probably be achieved for forest vegetation management programs that include non-herbicide alternatives. Key words: forest vegetation management, public opposition, risk perception, herbicides, biological control, prescribed fire, mulches, heavy equipment, cover cropping, grazing animals, manual cutting

Vegetation management for the maintenance and conservation of butterfly habitats in temperate human-dominated landscapes

Many temperate butterfly species occur in habitats where human activities have altered the natural or long-term disturbance regime, and current activities modify the structure and availability of butterfly habitats over several spatial and temporal scales. Indeed, human activities modify key ecological processes sufficiently that the maintenance of some butterfly populations depends on human intervention to provide suitable habitat. Combined changes in historic and current disturbance regimes and human land-use practices necessitate active vegetation and habitat management to conserve and expand many butterfly populations. Efforts to protect temperate butterfly habitats often have resulted in successional changes that reduce habitat suitability. Butterfly habitats commonly deteriorate through a reduced intensity and frequency of long-term disturbance or management patterns that result in smaller and fragmented patches of early successional habitat. Fragmentation of otherwise continuous habitats can result in the forced dependence of a metapopulation structure. Because some butterfly larvae require one or a few host plants or adults are selective for nectar or oviposition sites, habitat management plans that include selection of an appropriate site for subsequent vegetation management activities may enhance conservation efforts. Vegetation management activities within an area can be coordinated to provide a mosaic landscape with habitats suitable for numerous species. Recommended vegetation management strategies vary with plant community type, historic disturbance regime, desired vegetation structure and composition, spatial pattern of habitat patches, land ownership patterns, and economic constraints. Because butterflies respond directly and indirectly to vegetation management and to the mosaic nature of habitat patches within the landscape, management plans must accommodate the constraints of the regional landscape and the spatial and temporal dynamics of the prescribed disturbance or management regime. We review efforts to manage temperate plant communities for butterfly habitat, and discuss general strategies for developing a vegetation management program for butterfly habitats in human-dominated landscapes. A case study of Karner blue butterfly habitat conservation efforts is provided.

Restoring Native Perennial Grasses to Rural Roadsides in the Sacramento Valley of California: Establishment and Evaluation

AbstractAlong rural roadsides of the Sacramento Valley of California, we seeded native and non‐native perennial grasses to gauge their potential value in roadside vegetation management programs. In trial I (polycultures), three seeded complexes and a control (resident vegetation only) were tested. Each seeded plant complex included a different mix of perennial grasses seeded into each of several roadside topographic zones. The seeded levels of plant complex were: native perennial grasses 1 (8 species); native perennial grasses 2 (13 species); and non‐native perennial grasses (3 species). In trial II, plots were seeded to monocultural plots of 15 accessions of native Californian and three cultivars of non‐native perennial grasses. Plots in both trials were seeded during January 1992 and evaluated for three successive years.

Public attitudes towards forest herbicide use and the implications for public involvement

Public opposition to herbicide use in forest vegetation management has been an important issue for forest managers for more than a decade. Despite severe restrictions or elimination of herbicide use in many regions of North America, there have been limited attempts to understand public concerns and develop approaches for gaining public support of forest vegetation management programs. A three-part study was conducted in Ontario consisting of a comprehensive literature review of the herbicide issue, guided discussions with 12 focus groups, and development of a strategy for public involvement. A strategy for public involvement on forest vegetation management issues is proposed that includes: 1) information sharing, 2) resource sharing, 3) cooperative planning, and 4) collaborative action. Many of the ideas are applicable to other areas of natural resource management. Key words: public involvement, herbicides, forest vegetation management