Value for money? Investment in weed management in Australian rangelands

2006 ◽  
Vol 28 (1) ◽  
pp. 63 ◽  
Author(s):  
Tara G. Martin ◽  
Rieks D. van Klinken

Increased awareness of the threat posed by non-native species to biodiversity and productivity has prompted an unprecedented commitment and investment in weed management activities throughout rangeland Australia. Since the launching of National Weeds Program in 1996 under the first phase of the Natural Heritage Trust (NHT), there has been a substantial increase in coordinated and strategic investment in weed management across the rangelands. Almost AU$25 million of Australian Government funding has been invested in projects specifically targeting Weeds of National Significance (WONS) that occur in the rangelands (14 species) and a further AU$56 million on projects conducted in the rangelands that included a weed management component. Substantial funding has also been invested by other levels of government, non-government organisations and landholders. We review this investment in relation to the level of funding, the types of weeds targeted, the range of projects undertaken and the effectiveness of these projects within Australia’s rangelands. Achievements include successful eradications, preventions, early interventions, containments, mitigation of impacts, increased awareness of weed threats and general capacity to respond to weed management issues. Our review highlights several areas that, if addressed, will result in a substantial increase in the effectiveness of weed management efforts. These include: addressing discrepancies between states/territories in terms of funding and commitment to weed management; resolving conflicts between stakeholders in relation to the cost-benefit of non-native pasture grasses; encouraging projects that consider the broader natural resource management context of weed infestations; encouraging projects that examine weed complexes or the impacts of weeds in habitats with high biodiversity values such as riparian zones; and detecting and controlling weeds in the early stages of establishment. Finally, the collection of baseline information and alignment of reporting schedules with the longer term benefits of weed management projects will allow an assessment of the effectiveness of weed management projects and more strategic allocation of resources in the future.

2012 ◽  
Vol 36 ◽  
pp. 121-131 ◽  
Author(s):  
Jessica R. Miesel ◽  
Mark J. Renz ◽  
Julie E. Doll ◽  
Randall D. Jackson

Author(s):  
Stephanie G. Yelenik ◽  
Carla M. D'Antonio ◽  
Evan M. Rehm ◽  
Iain R. Caldwell

Abstract Unlike traditional successional theory, Alternate Stable Equilibrium (ASE) theory posits that more than one community state is possible in a single environment, depending on the order that species arrive. ASE theory is often invoked in management situations where initial stressors have been removed, but native-dominated communities are not returning to degraded areas. Fundamental to this theory is the assumption that equilibria are maintained by positive feedbacks between colonizers and their environment. While ASE has been relatively well studied in aquatic ecosystems, more complex terrestrial systems offer multiple challenges, including species interactions across trophic levels that can lead to multiple feedbacks. Here, we discuss ASE theory as it applies to terrestrial, invaded ecosystems, and detail a case study from Hawai'i that exemplifies how species interactions can favour the persistence of invaders, and how an understanding of interactions and feedbacks can be used to guide management. Our system includes intact native-dominated mesic forest and areas cleared for pasture, planted with non-native grasses, and later planted with a monoculture of a native nitrogen-fixing tree in an effort to restore forests. We discuss interactions between birds, understorey fruiting native species, understorey non-native grasses, soils and bryophytes in separate feedback mechanisms, and explain our efforts to identify which of these feedbacks is most important to address in a management context. Finally, we suggest that using models can help overcome some of the challenges that terrestrial ecosystems pose when studying ASE.


2019 ◽  
Vol 12 (1) ◽  
pp. 60-67 ◽  
Author(s):  
Shannon L. Clark ◽  
Derek J. Sebastian ◽  
Scott J. Nissen ◽  
James R. Sebastian

AbstractMinimizing the negative ecological impacts of exotic plant invasions is one goal of land management. Using selective herbicides is one strategy to achieve this goal; however, the unintended consequences of this strategy are not always fully understood. The recently introduced herbicide indaziflam has a mode of action not previously used in non-crop weed management. Thus, there is limited information about the impacts of this active ingredient when applied alone or in combination with other non-crop herbicides. The objective of this research was to evaluate native species tolerance to indaziflam and imazapic applied alone and with other broadleaf herbicides. Replicated field plots were established at two locations in Colorado with a diverse mix of native forbs and grasses. Species richness and abundance were compared between the nontreated control plots and plots where indaziflam and imazapic were applied alone and in combination with picloram and aminocyclopyrachlor. Species richness and abundance did not decrease when indaziflam or imazapic were applied alone; however, species abundance was reduced by treatments containing picloram and aminocyclopyrachlor. Species richness was only impacted at one site 1 yr after treatment (YAT) by these broadleaf herbicides. Decreases in abundance were mainly due to reductions in forbs that resulted in a corresponding increase in grass cover. Our data suggest that indaziflam will control downy brome (Bromus tectorumL.) for multiple years without reduction in perennial species richness or abundance. IfB. tectorumis present with perennial broadleaf weeds requiring the addition of herbicides like picloram or aminocyclopyrachlor, forb abundance could be reduced, and in some cases there could be a temporary reduction in perennial species richness.


2017 ◽  
Vol 39 (1) ◽  
pp. 85
Author(s):  
Michael R. Ngugi ◽  
Victor John Neldner

Naturalised non-native plants that become invasive pose a significant threat to the conservation of biodiversity in protected areas (areas dedicated and managed for long-term conservation of nature), economic productivity of agricultural businesses, and societal impacts including community, culture infrastructure and health. Quantifying the spread, potential dominance and invasion threat of these species is fundamental to effective eradication and development of threat mitigation policy. But this is often hampered by the lack of comprehensive data. This study used existing ecological survey data from 2548 sites and 64 758 Herbarium specimen records to document the status and abundance of non-native plants in two case study bioregions, Cape York Peninsula (CYP) and the Desert Uplands (DEU) in Queensland covering a total area of 186 697 km2. There were 406 non-native species in the CYP, 186 (45.6%) of which are known environmental weeds and 159 non-natives in DEU, of which 69 (43.5%) are environmental weeds. Inside the protected areas, there were 98 species of environmental weeds in CYP, 27 of which are listed as weeds of State significance (Weeds of National Significance (WONS), Queensland declared and non-declared pest plants categories). In DEU, there were 18 environmental weeds inside protected areas and none of them was listed as a weed of State significance. Non-native species that recorded foliage cover dominance in the ecological site data are generally recognised as environmental weeds in Queensland. The threat of weeds from outside of protected areas was serious, with 41 weeds of State significance found in CYP, five of which are WONS, and 25 weeds of State significance found in DEU, 10 of which are WONS.


2013 ◽  
Vol 19 (1) ◽  
pp. 39 ◽  
Author(s):  
Wayne A Houston ◽  
Robert L Black ◽  
Rod J Elder

The Capricorn Yellow Chat (Meliphagidae: Epthianura crocea macgregori) is a poorly known, endangered passerine of coastal north-eastern Australian wetlands. Recent research has highlighted the need for evidence based management and that recovery programmes may be hampered by a lack of sound ecological knowledge. Capricorn Yellow Chats were found at 15 sites near Rockhampton between Broad Sound and the Fitzroy River delta in the south. Overall, suitable habitat was limited with an area occupied of about 6 000 ha, confirming the need for careful management. Habitat may be typified as grass-sedge wetlands or tall supratidal saltmarshes that are temporarily flooded, with pools becoming brackish to hypersaline as they dry. Over 96% of sightings were on coastal plains formed by marine sedimentation processes, most without current tidal influence, and many less than 5 m above sea level. The remaining 4% were associated with alluvial-formed plains, but only where these bordered existing marine plain sites; suggesting a preference for marine plain habitats, possibly reflecting structural differences and foraging preferences (marine plains tend to be more open due to the presence of salt-tolerant samphire vegetation). Sea level rise was identified as a major threat to the subspecies with chat sightings at most sites averaging less than 2 m above current highest astronomical tidal influence, and sites becoming tidal or with regular storm surge influence under future modest predicted sea level rise scenarios of 0.5 m by 2100. Most sites had some form of banking to reduce tidal influence and promote freshwater pasture grasses for cattle production. The site supporting most chats had small banks that allowed floods to flow around them, maintaining connectivity with the downstream marine systems. This study contributes to baseline information essential to the evaluation of any future management interventions; thus avoiding the pitfalls hampering much of the global conservation efforts directed at threatened species.


2001 ◽  
Vol 7 (4) ◽  
pp. 274 ◽  
Author(s):  
S. McIntyre ◽  
K. M. Heard ◽  
T. G. Martin

A sample of 212 quadrats in grassland vegetation was collected in eucalypt woodlands in sub-tropical Queensland. These included roadside (53 sites), native pasture (109), riparian zone (20), sown pasture (16) and crop (14) habitats. A total of 350 species and subspecies was recorded of which 89 species were identified as being locally rare (native species of <3% frequency, not specialists of other habitats). Forty-three species were collected in addition to the quadrat records. Multivariate analysis indicated the major difference in floristic composition was between roadsides and native pastures, versus the other three habitats. The second axis separated roadside from native pasture vegetation, and the third axis separated riparian sites from all the rest. Crop and sown pasture habitats were the most similar in composition. The grazing practices in this region have enabled the persistence of grasslands that are of national significance in conservation terms. The variegated nature of the landscape is demonstrated by the occurrence of native grassland species across all the human-created habitats, including native species that were unique to intensive land uses. However, our results also show that intensive land uses (cropping, sown pastures) are more of a threat to the conservation status of grasslands than is cattle grazing, even at commercial levels of stocking. Species at most immediate risk are those that are sensitive to commercial cattle grazing and to intensive land uses such as crops and sown pastures.


Author(s):  
Albert E. Mayfield ◽  
Steven J. Seybold ◽  
Wendell R. Haag ◽  
M. Tracy Johnson ◽  
Becky K. Kerns ◽  
...  

AbstractThe introduction, establishment, and spread of invasive species in terrestrial and aquatic environments is widely recognized as one of the most serious threats to the health, sustainability, and productivity of native ecosystems (Holmes et al. 2009; Mack et al. 2000; Pyšek et al. 2012; USDA Forest Service 2013). In the United States, invasive species are the second leading cause of native species endangerment and extinction, and their costs to society have been estimated at $120 billion annually (Crowl et al. 2008; Pimentel et al. 2000, 2005). These costs include lost production and revenue from agricultural and forest products, compromised use of waterways and terrestrial habitats, harm to human and animal health, reduced property values and recreational opportunities, and diverse costs associated with managing (e.g., monitoring, preventing, controlling, and regulating) invasive species (Aukema et al. 2011; Pimentel et al. 2005). The national significance of these economic, ecological, and social impacts in the United States has prompted various actions by both legislative and executive branches of the Federal Government (e.g., the Nonindigenous Aquatic Nuisance Prevention and Control Act of 1990; the Noxious Weed Control and Eradication Act of 2002; Executive Order 13112 of 1999, amended in 2016).


2012 ◽  
Vol 65 ◽  
pp. 74-80
Author(s):  
C.S. Lusk ◽  
G.A. Hurrell ◽  
S.L. Lamoureaux

This study aimed to determine the effects of different management practices for Tradescantia fluminensis in lowland podocarp/broadleaf forest remnants in the lower North Island Fourteen 50 m line transects across eight sites were established in April 2009 and assessed annually until 2012 Management practices prior to and during the study period were documented Over the four assessments changes in the numbers of native plant seedlings and species differed greatly between management practices as did the percent cover of Tradescantia and other weeds Native species diversity improved more and the abundance of Tradescantia and other weeds increased less in forests that were less disturbed and where careful ongoing control was carried out than in forests with more disturbance prior to or during control operations Effective monitoring of both weeds and native plants is essential to enable the outcome of weed management practices to be measured


PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3307 ◽  
Author(s):  
Ross C. Langston ◽  
Heather L. Spalding

The invasive macroalgal species Avrainvillea sp. and native species Halimeda kanaloana form expansive meadows that extend to depths of 80 m or more in the waters off of O‘ahu and Maui, respectively. Despite their wide depth distribution, comparatively little is known about the biota associated with these macroalgal species. Our primary goals were to provide baseline information on the fish fauna associated with these deep-water macroalgal meadows and to compare the abundance and diversity of fishes between the meadow interior and sandy perimeters. Because both species form structurally complex three-dimensional canopies, we hypothesized that they would support a greater abundance and diversity of fishes when compared to surrounding sandy areas. We surveyed the fish fauna associated with these meadows using visual surveys and collections made with clove-oil anesthetic. Using these techniques, we recorded a total of 49 species from 25 families for H. kanaloana meadows and surrounding sandy areas, and 28 species from 19 families for Avrainvillea sp. habitats. Percent endemism was 28.6% and 10.7%, respectively. Wrasses (Family Labridae) were the most speciose taxon in both habitats (11 and six species, respectively), followed by gobies for H. kanaloana (six species). The wrasse Oxycheilinus bimaculatus and cardinalfish Apogonichthys perdix were the most frequently-occurring species within the H. kanaloana and Avrainvillea canopies, respectively. Obligate herbivores and food-fish species were rare in both habitats. Surprisingly, the density and abundance of small epibenthic fishes were greater in open sand than in the meadow canopy. In addition, species richness was also higher in open sand for Avrainvillea sp. We hypothesize that the dense holdfasts and rhizoids present within the meadow canopy may impede benthic-dwelling or bioturbator species, which accounted for 86% and 57% of individuals collected in sand adjacent to H. kanaloana and Avrainvillea sp. habitats, respectively. Of the 65 unique species recorded in this study, 16 (25%) were detected in clove oil stations alone, illustrating the utility of clove-oil anesthetic in assessing the diversity and abundance of small-bodied epibenthic fishes.


Author(s):  
Stephanie G. Yelenik ◽  
◽  
Carla M. D’Antonio ◽  
Evan M. Rehm ◽  
Iain R. Caldwell ◽  
...  

Unlike traditional successional theory, Alternate Stable Equilibrium (ASE) theory posits that more than one community state is possible in a single environment, depending on the order that species arrive. ASE theory is often invoked in management situations where initial stressors have been removed, but native-dominated communities are not returning to degraded areas. Fundamental to this theory is the assumption that equilibria are maintained by positive feedbacks between colonizers and their environment. While ASE has been relatively well studied in aquatic ecosystems, more complex terrestrial systems offer multiple challenges, including species interactions across trophic levels that can lead to multiple feedbacks. Here, we discuss ASE theory as it applies to terrestrial, invaded ecosystems, and detail a case study from Hawai'i that exemplifies how species interactions can favour the persistence of invaders, and how an understanding of interactions and feedbacks can be used to guide management. Our system includes intact native-dominated mesic forest and areas cleared for pasture, planted with non-native grasses, and later planted with a monoculture of a native nitrogen-fixing tree in an effort to restore forests. We discuss interactions between birds, understorey fruiting native species, understorey non-native grasses, soils and bryophytes in separate feedback mechanisms, and explain our efforts to identify which of these feedbacks is most important to address in a management context. Finally, we suggest that using models can help overcome some of the challenges that terrestrial ecosystems pose when studying ASE.


Sign in / Sign up

Export Citation Format

Share Document