All in Weeds

End-user needs for developing a national information system for weeds

superuser — Wed, 08 Jul 2009 07:40:58 +0000

This project clearly defines end user needs of a national information system for weeds. It highlights the ways in which BioSIRT, as a national emergency response data management tool for weeds, is not appropriate for broader application to end-user needs of a national information system. A generic framework and processes for developing a national information system for weeds is provided.

IDs and People

Program:

Defeating the Weed Menace R&D Program

Program Theme:

Supporting national frameworks for weed management

Subjects

Subjects:

Weeds

Current Activities

Status:

Complete

Improving targeting of weed biological control projects

Tue, 24 Mar 2009 00:06:59 +0000

In consultation with the Australian Weeds Committee and key stakeholders an analytical framework for prioritising weed targets for biological control programs has been developed. The framework presents opportunities for further refinement and integration with the recently developed Weed Risk Assessment process, to become an important national tool in identifying priority weeds species for biological control.

IDs and People

Program:

Defeating the Weed Menace R&D Program

Program Theme:

Supporting national frameworks for weed management

LWA Project Code:

LRN004729

Subjects

Subjects:

Weeds

Project Information

Summary:

Considerable investment over several decades has been directed to the search for biological control agents against weed species. This work has generally been a public activity carried out by government agencies and research institutions, rather than by the private sector. Success of this work has varied widely across a broad range of different species. Work to date has focused more on the selection, testing and evaluation of biological control agents than on understanding how to best select target weeds against which biological control might play an important part. In seeking to improve the targeting of weed species suitable for biological control, and thus the return on effort and resources invested, this project sought to develop a framework taking account of such factors as the importance of the weed problem and the feasibility of biological control.

Outcomes:

The project reviewed previous work related to selection and prioritisation of weed biological control targets
The project developed and tested an initial framework that incorporates the two main features of previous ranking protocols (weed importance, based largely on the Australian Weeds of National Significance ranking, and predicted impact of biological control), but built on these by testing hypotheses regarding impact of biological control.

To validate this framework we correlated feasibility score against impact index for individual South African and USA datasets.

This preliminary framework was presented to stakeholders to obtain feedback on the proposed scheme and seek further information about the Australian weeds to be prioritised.

Following the workshop the scoring system was further refined by incorporating quantitative data from Australian weed biocontrol programs and refining the scoring system using sensitivity analysis. Using the final scoring system, biocontrol impacts were invariably major against weeds that scored more than c. 70 (out of 100). For weeds that scored between 50 and 70, impact was variable (approximately 40:60 successes and failures), while biocontrol most often had no impact against weeds that scored less than 50.

The revised framework was then applied to Australian weeds on the WoNS and AWC lists, and used to prepare a list of weeds in priority order.

The framework, rationale, methodology, and assumptions made in developing the prioritisation scheme and the results of running the WoNS and AWC lists through the scheme are presented within the final report, which also provides recommendations for a nationally prioritised list of Australian weed biocontrol targets, plus recommendations for future application of the framework.

Current Activities

Status:

Pending

Background

Project Background:

Most classical biological control projects against weed targets have been conducted in South Africa, Australia, New Zealand, the USA and Canada. Classical biological control tends to be a public, community-level activity carried out by institutions and public departments rather than private enterprise (Van Driesche & Hoddle 2002). The need to account for this public investment should ensure robust decision-making processes, with the intention of selecting biocontrol targets that are important, are biologically and ecologically feasible, and have broad social support. In practice, the means by which targets are selected vary greatly between jurisdictions, and there have been few attempts to develop systems that can achieve this end in a transparent and repeatable fashion. There has also been surprisingly little underpinning research to ensure that the most important criteria are used.

Aims:

To develop an analytical framework for prioritising target weeds for biological control programs. This was achieved by recognising that impact and feasibility are important considerations in biological control. The framework for prioritising target weeds for biological control shall consider issues such as: whether the weed has been the subject of a successful or unsuccessful program overseas; whether there is significant opposition to biological control; and the taxonomic proximity to native or valued exotic plants (e.g. congeneric crops), which may increase the risk of non-target damage, thereby reducing the pool of suitable candidate agents.

The project tasks shall be to:

Review previous work related to selection/prioritisation of weed biocontrol targets.
Develop the prioritisation framework with input from highly experienced biocontrol researchers, entomologists, pathologists, botanists, and weed ecologists to ensure all relevant aspects are considered.
Undertake an initial test of the framework: Validate and refine the prioritisation scheme, using international examples of completed projects to compare predictions with real-life outcomes.
Facilitate a workshop to gain input into the framework.
Run the Australian weeds through the framework: Acquire relevant data for each species on the WONS and AWC lists and then run each species through the prioritisation scheme.
Provide a Final Report and the Final Prioritisation Framework outlining the rationale, methodology, and assumptions made in developing the prioritisation scheme and the results of running the WONS and AWC lists through the scheme. This will give recommendations for a nationally prioritised list of weed biocontrol targets, plus recommendations for future application of the scheme. The prioritisation scheme tool will be delivered in a user-friendly format, like similar schemes used for weed risk assessment (e.g. a Microsoft Excel tool).
Present the Final Prioritisation Framework to stakeholders in Canberra.
In addition, recommendations shall be made for future application of the scheme, for example, by identifying gaps in knowledge where additional research might lead to refinements of the scheme.

Ecological, economic and social considerations of spray control for Hymenachne

Mon, 18 Aug 2008 06:21:26 +0000

IDs and People

Program:

Defeating the Weed Menace R&D Program

Program Theme:

Quantifying the impacts of weeds on sustainability and the environment and the relative benefits and costs

Research Type:

Research Project

Legacy (KMS) Project ID:

UCQ4

Host Organisation:

Central Queensland University

Researchers:

B.Miles

J.Rolfe

L.Duivenvoorden

W.Houston

Subjects

Subjects:

Data and Information

Weeds

Keywords:

Weeds

Project Information

Summary:

Hymenachne, a Weed of National Significance (WONs), is an aquatic plant invading northern Australia’s wetlands and waterways. The proliferation of this weed is associated with serious ecological losses and there are substantial costs associated with its control. Hymenachne also deserves special attention given the nexus regarding its beneficial use as a ponded pasture species for livestock production and drought management, and the disadvantages associated with its spread and ecological impact. A key challenge in the management of this weed is to understand the best ways to approach Hymenachne control, whilst satisfying environmental, social and economic concerns.

This study used a triple bottom line approach to improving the understanding of the issues facing Hymenachne control. This involved the integration of the social, economic and ecological studies and ecological surveys conducted in conjunction with a sample spray regime.

Outcomes:

Key findings were the need for a coordinated and inclusive approach to Hymenachne control across all stakeholders and landholders, with suitable incentives being made available and responsibility taken for control by each of the Government, Councils and the community. With respect to chemical control spraying, there was little evidence that this causes long-term, significantly negative effects on freshwater systems with respect to water quality, pesticides residuals, and biota (macroinvertebrates, fish and semi-aquatic invertebrates). This contrasts with the known adverse ecological effects of dense Hymenachne cover demonstrated in earlier studies, thus suggesting that control sprays should be employed to reduce existing infestations and prevent new outbreaks.

Current Activities

Status:

Complete

Background

Project Background:

Hymenachne, a Weed of National Significance, is an aquatic pest plant that is invading northern Australian wetlands and waterways. Its proliferation is associated with serious ecological issues and there are substantial costs associated with its control. However, Hymenachne is also valued by some livestock producers as a ponded pasture important in drought management.

A significant challenge for the control of Hymenachne is to balance the economic, social and environmental costs and benefits of its use and management.

Aims:

Project objectives:

1. A detailed review of literature will report on issues including, but not limited to, the current spread of Hymenachne, existing methods for control, available data on ecological consequences of spray regimes and the socio-economic impacts of the weed and different control measures.

2. The ecological component of the study will address the following research questions:

(a) What are the adverse ecological impacts associated with chemical spray regimes (e.g., decline in water quality, changes to aquatic habitats, loss in vertebrate & invertebrate biodiversity)?

(b) What is the extent of system recovery in the short term, following spray and/or successful hymenachne control (possibly including recolonisation by native vegetation)?

3. The key research questions for the economics component relate to the knowledge, barriers and incentives that will generate participation in control strategies:

Quantifying the economic costs of control and the level of incentives needed to generate effective participation
on-farm economic losses due to lost production where Hymenachne is removed from ponded pastures
costs of control measures
types and levels of incentives needed to encourage on-farm control activities,
the structure of incentive mechanisms needed to generate sufficient participation by landholders at a landscape scale.

4. The investigation of broader social issues regarding Hymenachne will include questions such as:

What is the current level of awareness & perceptions of the Hymenachne problem in central Queensland by landholders?
What is the extent of willingness to participate in control programs?
What barriers, catalysts and enablers influence landholder adoption of, and/or cooperation with, Hymenachne control regimes?
An analysis of conflicts of interest existing in regards to Hymenachne as (a) a ponded pasture grass used for livestock production and (b) an ecologically destructive weed of national significance
Investigations of strategies that could be put in place to foster greater awareness of the weed problem, cooperation across stakeholder groups and a wider adoption of control

Evaluating the environmental benefits from managing WoNS in natural ecosystems

Mon, 18 Aug 2008 06:15:05 +0000

IDs and People

Program:

Defeating the Weed Menace R&D Program

Program Theme:

Quantifying the impacts of weeds on sustainability and the environment and the relative benefits and costs

Research Type:

Research Project

Legacy (KMS) Project ID:

cen24

Host Organisation:

CSIRO Entomology

Researchers:

Dr. Louise Morin

Dr Adele Reid

Subjects

Subjects:

Data and Information

Weeds

Keywords:

Bitou Bush

Bridal Creeper

Project Information

Summary:

Weeds pose a significant threat to natural ecosystems in Australia and consequently large quantities of resources are spent each year to control them. This project undertook a desktop analysis to determine the current state of knowledge on how native communities and ecosystem processes recover following weed control.

Outcomes:

Given the combined findings of the three components of this project, it is clear that management programs for WoNS and other weed species in natural ecosystems should put greater emphasis on monitoring the response of native species to the reduction or removal of the target weeds. Some monitoring is essential to identify if the control methods used damage native plants and to provide information to decide whether additional interventions are required to assist native plant communities recover. Microbial and animal communities, and ecosystem processes should also be monitored to get a more complete assessment of how natural ecosystems respond to weed control, but it is acknowledged that it is unrealistic to expect on-ground land managers to implement this type of detailed monitoring. Such monitoring is better left for trained researchers to undertake at representative sites to address current knowledge gaps.

Collectively, the findings suggest that a whole-system approach, integrating weed management programs with other actions to assist the recovery of native communities may be essential to restore the structure and function of many affected ecosystems and protect against future weed invasion. Long-term monitoring would be crucial to evaluate the effectiveness of this integrated approach in restoring an ecosystem.

Current Activities

Status:

Pending

Background

Project Background:

Controlling an individual weed species is a major achievement, especially where that weed is a Weeds of National Significance, identified for its major impacts on productivity and the environment. However weeds are just one part of the landscape, and if native plant communities and ecosystem functions such as water flows and nutrient cycling do not recover once the weed is removed, then it is difficult to claim real success in managing the weed.

This desktop study examined the extent to which native plant communities and ecosystem functions have recovered after major weeds have been controlled and to provide advice on improving long-term success of future weed management.

Aims:

The aim of this project was to undertake a desktop analysis to determine the current state of knowledge on how native communities and ecosystem processes recover following weed control in natural ecosystems. This was achieved by three investigations:

reviewing the relevant scientific literature,
surveying stakeholders and
analysing data from field experiments on the WoNS bridal creeper (Asparagus asparagoides) and bitou bush (Chrysanthemoides monilifera ssp. rotundata).

Quantification of the environmental and control costs of weeds

Mon, 18 Aug 2008 06:06:13 +0000

IDs and People

Program:

Defeating the Weed Menace R&D Program

Program Theme:

Quantifying the impacts of weeds on sustainability and the environment and the relative benefits and costs

Research Type:

Research Project

Legacy (KMS) Project ID:

NTU25

Host Organisation:

Charles Darwin University

Researchers:

Samantha Setterfield

Subjects

Subjects:

Data and Information

Monitoring and Assessment

Weeds

Keywords:

Quantifying the impacts of weeds on sustainability and the environment and the relative benefits and costs of different control

Project Information

Summary:

The purpose of this project was to quantify

the environmental impacts and
the relative benefits and costs of control of two tropical invasive grasses.

The project reviewed the existing studies on the environmental impact of tropical invasive grasses in order to identify the main impacts that should be the focus of economic analysis of control methods.

The project contributed to this knowledge by completing research that demonstrated the impact of invasive grasses on the structure and function of tropical ecosystems, and the impact of management practices on ecosystem health and capacity for restoration. The project completed case studies demonstrating the effect and cost of exotic grass invasion on fire management practices, and the methods and costs of control approaches.

The project developed an approach to assessing the benefits of control of ‘conflict of interest’ weeds and the relative cost-effectiveness of alternative control measures. These approaches have already been used by the NT Government to guide decision making about tropical invasive grasses within their weed risk management framework.

The project will build on the existing strong national linkages established during the development of the NT WRM process, which was developed in consultation with WRM experts from South Australia, Victoria, Queensland, NSW and WA.

Outcomes:

The project was completed as a collaboration between Charles Darwin University and the Northern Territory Government. Development of the research questions and approach and collection of data were done in collaboration with the main end user – the NT Government. This provided a clear pathway for adoption, and ensured that the project was directly relevant to the management needs.

The outputs have already been incorporated into decision-making processes as demonstrated by the inclusion of the BCA of gamba grass, particularly the fire management costing, in the NT and Queensland Government’s nomination for declaration. The NT Bushfires Council has used the economic costs of gamba grass management to secure a substantial increase in operation budget. The NT Government has committed to further work on the framework for assessing alternative control measures to apply to other case study species.

Current Activities

Status:

Complete

Background

Project Background:

Weed management agencies support the principle that prioritisation of, and investment in, weed management must be informed by a risk management approach (Australian Weeds Strategy 2007), and in Australia this prioritisation process should be guided by Australia’s "Post-border Weed Risk Management (WRM) Protocol" (Virtue et al. 2007).

However, while there is nationwide agreement that the elements within the WRM Protocol represent best practice, the availability of some of the decision support tools that underpin such a system have been identified as knowledge gaps or needing refinement following additional R&D. In particular there have been calls for WRA to expand to include tools that assess the range of environmental and economic costs, and to assess the costs, risks and likely success of weed control measures (Wainger and King 2001).

Aims:

The purpose of this project is to fill two key knowledge gaps in Australia’s Post-border WRM system. The project aimed to quantify:

The environmental impacts
The relative benefits and costs of control measures of two invasive grasses within a case study context.

The research proposal also did the following:

A review of existing material and a synthesis related to the environmental impact of weeds, in order to identify the main impacts that should form the focus of the economic analysis;
The development / adaptation of a framework for assessing the relative cost-effectiveness of alternative control measures;
The development / adaptation of a framework for assessing the benefits of control of ‘conflict of interest’ weeds.

Pinus radiata in bushland: Assessing the issue in the Green Triangle

Mon, 18 Aug 2008 05:54:12 +0000

IDs and People

Program:

Defeating the Weed Menace R&D Program

Program Theme:

Quantifying the impacts of weeds on sustainability and the environment and the relative benefits and costs

Research Type:

Research Project

Legacy (KMS) Project ID:

DEH8

Host Organisation:

Department of Environment and Heritage SA

Researchers:

Mark Bachmann

Subjects

Subjects:

Data and Information

Weeds

Keywords:

Quantifying the impacts of weeds on sustainability and the environment and the relative benefits and costs of different control

Project Information

Summary:

Pinus radiata is recognised, both in Australia and elsewhere, as a potential weed impacting on natural areas and habitat values. This project will quantify the extent and distribution of pine wildlings as they invade remnant native vegetation areas. It will provide outcomes that inform the plantation industry and NRM planners on improved management of Pinus radiata. Although focused on the Green Triangle in SE South Australia and SW Victoria, the project will also include other pine growing areas.

Outcomes:

Key messages that have emerged from this study are:

Application of remote sensing to identify pine wildlings in native vegetation is a difficult process. It will take further development before it realises its full potential for planning, management or research
Incorporating communication and networking with the key interested parties from the inception of a project has been particularly useful in defining the direction of the study and obtaining information that field operators have about actual pine wildling presence
Further development of remote sensing to detect pine wildlings is eminently worth doing and will prove even more so when the next generation of high resolution, multi-spectral imagery becomes available.

Current Activities

Status:

Pending

Background

Project Background:

Pinus radiata has recognised weed potential both in Australia and overseas. Research to date has demonstrated its invasive potential and its ability to alter structure and species composition of native vegetation. This leads to an impoverished plant community and reduced habitat value for native fauna, particularly important where native vegetation is already greatly reduced in extent. The threat becomes so much greater where these remnants lie next to pine plantations that are much larger in extent than the native vegetation.

While much is known about establishment and growth of pines in plantations, the ecology of pine wildlings invading native vegetation in Australia is less well documented.

As is generally the case with environmental weeds, it is most cost effective to control pine wildlings at the early stage of invasion. This requires that they be identified while their numbers and size are fairly small; not a quick or easy task in forest and woodland vegetation.

Aims:

This project aims to:

Develop use of GIS to identify pine wildlings in remnant vegetation, preferably using satellite imagery;
Quantify the extent of invasion of remnant native vegetation by P. radiata seedlings (wildlings) in the Green Triangle region, the lower SE of SA and SW of Victoria
Develop projections of the potential impact of P. radiata by relating vegetation community characteristics, distance from plantations and age of plantations;
Identify current and potential management options for control of pine wildlings and estimate costs of these options.

Quantifying costs and benefits of buffel grass

Mon, 18 Aug 2008 05:47:02 +0000

IDs and People

Program:

Defeating the Weed Menace R&D Program

Program Theme:

Quantifying the impacts of weeds on sustainability and the environment and the relative benefits and costs

Research Type:

Research Project

Legacy (KMS) Project ID:

CSE52

Host Organisation:

CSIRO Sustainable Ecosystems

Researchers:

Margaret Friedel

Subjects

Subjects:

Data and Information

Weeds

Keywords:

Quantifying the impacts of weeds on sustainability and the environment and the relative benefits and costs of different control

Project Information

Summary:

Through an initial literature review, focus groups and interviews, this project aims to quantify the impacts of Buffel grass on sustainability and the environment, and to assess from both environmental and pastoral perspectives, the relative benefits and costs of different approaches to management. The results will provide improved management recommendations that are credible to land owners and managers as well as to environmental policy makers.

More information about Buffel Grass is available in the latest edition of Thinking Bush (pages 16-17).

Outcomes:

10 recommendations for improved buffel grass management were established:

Objectives, strategies and tools for management of buffel grass must be considered within a local to regional context
Manage change through involving landholders in an open dialogue about the costs and benefits of buffel grass and in the setting of common goals
Understand and use landholders’ formal and informal networks to enhance information exchange
Recognise and accept the transaction costs of community engagement so that the social benefits of buffel grass can be maximised and the environmental costs minimised
In situations where buffel grass is yet to colonise large areas, particularly in southern Australia, initiate early community discussion about the benefits and costs of buffel grass and its management
Improve understanding of management options and benefits/costs through documenting existing experience and developing new research; keep regional differences in focus
Develop processes for identifying and prioritising areas of high biodiversity value where management of buffel grass is required
Develop incentives for landholders to deliver environmental outcomes at landscape scale through management of buffel grass
Develop policy recommendations for governments through establishment of representative advisory groups at state and cross jurisdictional levels
Develop a national strategy for the sustainable management of buffel grass for production and conservation, relevant to regional scales.

Current Activities

Status:

Pending

Background

Project Background:

Buffel grass is a major environmental weed with the potential to establish in over 60% of mainland Australia. It is also highly prized by many pastoralists as an exotic pasture grass for livestock. Within these two conflicting views there is a spectrum of opinions on the relative benefits and cost of managing impacts of buffel grass in a sustainable way. The objective of the project was to quantify the impacts of buffel grass on sustainability and the environment and the relative benefits and costs of different approaches to management.

Aims:

The objective is to work with agencies, regional groups and individuals to:

Document the environmental, social and economic benefits and costs of buffel grass invasion to both conservation and pastoral sectors
Identify and describe current and potential management objectives, strategies and operational methods and their relative benefits and costs
Determine the perceptions of key stakeholders to different objectives, strategies and operational methods for dealing with buffel grass
Identify the potential for change in perceptions, attitudes and values and determine pathways for disseminating information about buffel grass and its management or control
Develop specific recommendations, based on our findings, on how to improve the management of buffel grass, and disseminate them as effectively as possible
Provide a general approach to improve management of contentious weed issues that considers both costs and benefits and the sociological barriers to change

Cost-effective surveillance of emerging aquatic weeds using robotic aircraft

Mon, 18 Aug 2008 05:23:08 +0000

IDs and People

Program:

Defeating the Weed Menace R&D Program

Program Theme:

Developing efficient methods for surveying and eradicating agreed emergent weeds, and options

Research Type:

Research Project

Legacy (KMS) Project ID:

USY13

Host Organisation:

University of Sydney

Researchers:

Assoc. Prof. Salah Sukkarieh

Subjects

Subjects:

Data and Information

Innovation

Weeds

Keywords:

Salvina

Robotics

Infrared

Project Information

Summary:

In the 2007/2008 Defeating the Weed Menace R&D program, a novel approach to the detection and eradication of emerging aquatic weeds was presented. The Australian Centre for Field Robotics (ACFR) at the University of Sydney proposed the development of an autonomous weed controller: one that wouldn’t tire, would travel large distances, and wouldn’t mind traversing through difficult to access areas in the hope of detecting and eradicating nasty weeds – and so it was, the Weedinator was born.

The ACFR are world renowned for their exploitations in autonomous systems – basically robots that can do all the “dull, dirty and dangerous” tasks that are out there. The group has worked on novel systems, delivered a number of world firsts, and commercialised many of their products in the areas of logistics, mining, defence, agriculture and art.

Outcomes:

The platform is a modified G18 model helicopter from UVA Vision www.uavision.com . Using a helicopter meant full manoeuvrability could be attained, including hover, thus giving the ability to traverse large distances, move into tight situations, and hold position to take imagery or to spray. This involved development and tuning of flight control and navigation algorithms, as well the spray mechanisms. The final system could fly for approximately two hours and carry approximately 500ml of herbicide (although water was used in this project for demonstration).

The detection algorithms were based on novel machine learning techniques that are currently very popular in the scientific community. The basic principle is that instead of developing algorithms that specifically try to model what a weed is (this approach has always failed in the past), why not develop an algorithm that learns the model itself. Such approaches mimic the way the human brain learns. With such an algorithm you give it many images of the weed of interest, and many images that are not the weed of interest. You tell the algorithm which is what, and then leave it alone while it learns the key differences, focussing on qualities such as colour, shape and texture.

The algorithms proved to be very robust and accurate and were tested on Alligator weed and sprayed Salvinia.

Current Activities

Status:

Complete

Background

Project Background:

Waterways often include places that are difficult to access. When aquatic weeds establish in these areas they present problems both for detection of the weeds and for treatment to manage their spread or eradicate them.

Using small unmanned aircraft equipped with low-cost sensing cameras and combining these with new technologies to analyse spectral data obtained, different plant species can be ‘finger-printed’ in ways that allow weeds to be detected in places that were previously relatively inaccessible.

Aims:

Projective objectives were three fold:

To provide weed control authorities a cost-effective surveillance tool for the detection of emerging aquatic weeds. The system is an autonomous Hovering Unmanned Air Vehicle (HUAV) – a robotic helicopter – fitted with low-cost sensor suites and intelligent aquatic weed detection algorithms. Such a system can provide coverage over large distances and inaccessible aquatic habitats.
To develop a spray mechanism for the HUAV that provides the weed control operators the capability of autonomous or remote control spraying and treatment of these aquatic weeds in inaccessible aquatic habitats.
To gather geo-referenced spectral and visual data of aquatic weeds in inaccessible aquatic habitats. This data can be used to conduct further research in spatiotemporal weed growth.

Location

State & NRM Region:

National

Resources

External Links:

Australian Centre for Field Robotics

Exploring agents of change to peri-urban weed management

Mon, 18 Aug 2008 04:49:51 +0000

IDs and People

Program:

Defeating the Weed Menace R&D Program

Program Theme:

Developing efficient methods for surveying and eradicating agreed emergent weeds, and options

Research Type:

Research Project

Legacy (KMS) Project ID:

UMCC1

Host Organisation:

Upper Murrumbidgee Catchment Coordinating Committee

Researchers:

Jo Harding

Subjects

Subjects:

Data and Information

Weeds

Keywords:

Developing efficient methods for surveying and eradicating agreed emergent weeds

and options

Project Information

Summary:

This project aims to undertake a social research study in the Upper Murrumbidgee catchment, targeting rural lifestyle landowners, to determine the driver to land use change in relation to invasive weeds. The results from this research will provide important input to weed management strategies and aid in the development of efficient methods for surveying and eradicating emergent weeds.

The research will primarily follow methods used by Aslin & Mazur in their 2005 study “Bio-security awareness and peri-urban landholders: a case study approach”. These methods were found to be the most appropriate for collecting qualitative and quantitative data when undertaking a social survey of rural lifestyle landowners.

Outcomes:

The research team are currently reviewing the findings from this study to develop a series of recommendations including engagement of Rural Lifestyle Landholders (RLLs) in weed management and NRM in general. These findings will be incorporated into the final printed report. The findings will be used to develop and pilot a public weed identification workshop specifically designed for RLLs in the case study areas. Results from this event will be included as an appendix to the final printed report.

Current Activities

Status:

Active

Background

Project Background:

Rural Lifestyle Landowners are a key stakeholder in future landscape management, and can be viewed as potential threats or possible allies in natural resource management (Hollier at. al. 2004). Lack of knowledge, different values and time limitations combine to make rural lifestyle landowners a potential source of increased emergent weeds, weed spread and general poor land management (Aslin & Mazur 2005). However, rural lifestyle landowners are also typically well educated, have high incomes and value natural landscapes (Buxton et. al. 2006).

Aslin & Mazur (2005) have noted that rural lifestyle landowners have been identified as a potential bio-security risk group, and that concerns have been expressed about how information and awareness campaigns are reaching this part of the rural population. One of the most common bio-security risks associated with this segment of the rural community is the risk of introducing and spreading weeds. It is important that weed management strategies, and efficient methods for surveying and eradicating emergent weeds consider lifestyle / peri-urban lands and the different values, culture and knowledge levels of rural lifestyle landowners.

There have been a number of social studies undertaken on peri-urban areas (Aslin & Mazur, 2005; Hollier et. al. 2004; Buxton et. al. 2006; Mackenzie et. al. 2006; Curtis et. al. 2000). These studies have, however, focused on developing a broader understanding of natural resource management issues. There is little social data on rural lifestyle landowners in relation to weeds and land use of rural lifestyle landowners in areas of the Upper Murrumbidgee catchment.

Aims:

This project aims to undertake a social research study in the Upper Murrumbidgee catchment, targeting Rrural Lifestyle Landowners, to determine the drivers to land use change in relation to invasive weeds. The results from this research will provide important input to weed management strategies and aid in the development of efficient methods for surveying and eradicating emergent weeds.

Location

State & NRM Region:

New South Wales

Australian Capital Territory

Best Practice for On-ground Property Weed Detection

Mon, 18 Aug 2008 04:41:01 +0000

Through phone surveying of landholders and noxious weed officers, this project better identified current weed surveillance levels and practices on farms and ways to improve weed detection. Because of the large area of Australia owned and managed by farmers and graziers, the project has used this information to develop a guide for landholders, on how to look for weeds, get them identified and report them to the relevant authorities.

IDs and People

Program:

Defeating the Weed Menace R&D Program

Program Theme:

Developing efficient methods for surveying and eradicating agreed emergent weeds, and options

Research Type:

Research Project

Host Organisation:

University of New England

Researchers:

Prof Brian Sindel

Subjects

Subjects:

Data and Information

Weeds

Keywords:

Developing efficient methods for surveying and eradicating agreed emergent weeds

and options

Current Activities

Status:

Complete

Background

Project Background:

There have been attempts to develop guidelines for professional surveying and mapping of nationally significant weeds and in national parks, weed spotting networks, and surveillance techniques for weeds that have already been detected in Australia such as branched broomrape. However, a large proportion of Australia is privately owned or managed by farmers and graziers, and yet no one has undertaken a comprehensive study to ascertain current weed surveillance levels and practices amongst these landholders or the noxious weeds inspectors (or their equivalents in each state) that already regularly check properties for new and existing invasive plants.

Aims:

The purpose of this research is to:

Assess current weed surveillance levels and practices amongst landholders and noxious weeds inspectors; and
Identify ways to improve weed detection by these groups on-ground.

Resources

External Links:

Weed Detection on Farms: A guide for landholders (PDF)

Elucidating relationships between disturbance and invasion in riparian zones

Mon, 18 Aug 2008 04:33:38 +0000

IDs and People

Program:

Defeating the Weed Menace R&D Program

Program Theme:

Weed management strategies that incorporate an understanding of landscape scale ecological processes

Research Type:

Research Project

Legacy (KMS) Project ID:

VPI15

Host Organisation:

Victorian Department of Primary Industries

Researchers:

Dr Fiona Ede

Subjects

Subjects:

Data and Information

Landscape Management

Weeds

Rivers and Wetlands

Keywords:

Developing new integrated weed management strategies that incorporate an understanding of landscape scale ecological processes

Project Information

Summary:

This project sought to develop improved riparian weed management strategies by analysing the linkages between disturbance from flood events and both weed invasion and tree recruitment in riparian areas. Analysis of an existing dataset containing assessments of vegetation variables from 23 rivers across Victoria resulted in the development of predictive models relating the number of eucalypt and acacia seedlings at a site to the number of parent trees, the amount of bare ground, the catchment management region and the cover of native sedges (eucalypt seedlings only).

Outcomes:

The cover of exotic life forms and number of exotic taxa did not affect tree seedling numbers, indicating that weeds did not inhibit tree recruitment at the landscape scale in the sites studied. A new dataset containing hydrological variables for the rivers under study was compiled and initial regression of these variables against the vegetation variables was undertaken. The cover of various exotic life forms was not affected by flood frequency or the total, average or longest duration of floods, while the total cover of weeds decreased as the number of flood events increased. Sites with more frequent and longer duration floods had a higher proportion of native to exotic taxa. The number of days that the riparian area was under water was negatively related to the number of eucalypt and acacia seedlings found at a site. Riparian weed management guidelines have been developed, in association with on-ground managers, which provide information and advice which can be incorporated into weed management programs seeking to enhance the condition of riparian areas.

Current Activities

Status:

Complete

Background

Project Background:

Riparian zones are highly dynamic landscape components, forming the interface between aquatic and terrestrial ecosystems. Flood events are integral to the functioning of riparian zones, by periodically redistributing energy and materials. This results in heterogenous ecosystems providing numerous microsites in which different plants can establish. In both Australia and overseas it has been found that a wide range of native and exotic species exploit these microsites, making riparian zones some of the most biodiverse communities in the landscape.

This, however, results in sites with multiple weed species, increasing the complexity of weed management. This is further compounded by the limitations on chemical control methods which can be applied near waterways, while the presence of some level of native vegetation in the riparian zone also limits control options. This is particularly important in sites where the vegetation community depends on natural regeneration processes as some weed control strategies can destroy entire cohorts of young native plants.

Aims:

By elucidating the relationships between the disturbance caused by flooding and weed invasion, and tree recruitment, this project will be able to provide land-managers with guidelines so their weed management activities can optimise tree recruitment and the creation of these bare areas through flooding, it is highly probable that the period immediately after a flood event is critical to tree seeding establishment. Understanding the dynamics of weed invasion and establishment during this recruitment window will allow the development of appropriate weed management strategies. It is possible that these strategies may differ, not only depending on the mix of weeds present, but as a consequence of river type.

The objectives of this project are to develop improved riparian weed management strategies for land managers, incorporating analysis of the linkages between:

Disturbance from flood events and weed invasion in riparian zones;
Disturbance from flood events and the recruitment of native tree species.

The outputs from this project are threefold:

Riparian weed management guidelines;
Weed manager training;
Scientific paper.

Location

State & NRM Region:

Victoria

Optimising management of core mesquite infestations in Australia

Mon, 18 Aug 2008 04:18:50 +0000

IDs and People

Program:

Defeating the Weed Menace R&D Program

Program Theme:

Weed management strategies that incorporate an understanding of landscape scale ecological processes

Research Type:

Research Project

Legacy (KMS) Project ID:

CEN23

Host Organisation:

CSIRO Entomology

Researchers:

Dr Rieks van Klinken

Subjects

Subjects:

Weeds

Keywords:

Developing new integrated weed management strategies that incorporate an understanding of landscape scale ecological processes

Project Information

Summary:

Mesquite (Prosopis sp) is a highly invasive shrub that forms dense thorn forests in semi-arid and arid Australia. Several mesquite taxa (species and hybrids) are invasive in Australia, with core infestations occurring in the Pilbara, northern Queensland and south-west Queensland. This project team conducted a three-year field study to test whether the invasiveness of mesquite, and its response to biological control, differs with taxa and climate (between region and years).

Outcomes:

Key results from the mesquite research can be summarised as the following recommendations:

Management efforts should continue through dry periods as seed production is low. Also, the seed bank will continue to decline through ongoing dormancy-release and germination, but most seedlings will fail to establish.
Surveillance efforts (including for eradication or containment programs) should be particularly vigilant 2-5 years after high recruitment years when surviving recruits are likely to become visible, but prior to them setting seed. The timing and frequency of high recruitment years should be predictable using soil moisture models and our knowledge of requirements for seedlings recruitment.
Most seeds are dispersed through vertebrate herbivores. Management of dispersal, and search strategies for finding new recruits, should therefore be based on a good understanding of the movement patterns of the dominant vertebrate herbivores. Also, the seed bank can be expected to be relatively diffuse (unless concentrated by herbivores such as around water points).
Eradication programs are conducted until the seed bank is exhausted. Mesquite seed bank density is low and seed banks are potentially relatively short-lived. Although surveillance programs may still need to be continued for many years, new recruits, and therefore control costs, should be limited after the first few years.
Control programs need to be aware that the density of difficult-to-spot juveniles can far exceed that of the adult population, and that they can remain quiescent for long periods of time (as a “sapling bank”) if conditions are not optimal for growth. Control of adult trees can stimulate massive and rapid growth from the sapling bank, which can make the weed problem worse if follow-up control is not done.
Predicting the potential spread and impact of mesquite at the catchment-scale is relatively straightforward, and such predictions should form the basis of management efforts, including targeted surveillance and education programs, the placement of containment lines and internal fencing for core infestations, and the prioritisation of on-ground control work.
Seed-predators offer little or no control benefits, and need not be integrated into a management strategy.
The leaf-tying moth is extremely damaging to mesquite in the Pilbara, and is probably also causing significant impact on hybrid mesquite in Queensland. No specific management actions are required to manage this moth, as it is a good disperser and populations can build up rapidly (for example after control work). However, ongoing low-level monitoring is worthwhile to ensure moth populations don’t decline (e.g. in response to wet conditions or following parasitism) allowing the mesquite population to expand.
Greater mesquite density and dispersal should be expected in the incipient core infestation located on the delta of the Robe River than has recently been observed in the core infestation on the Fortescue River, as the leaf-tying moth does not appear to be having as much impact there.
The response of mesquite populations to climate change should be predictable based on our knowledge of the relationship between climate, recruitment, and seed production.
Field work was conducted in low to average rainfall years. It is worth continuing low-level monitoring to capture what happens during and following wet years.

Current Activities

Status:

Pending

Background

Project Background:

Several core mesquite infestations have been identified in the national mesquite management strategy (2001) for containment and, in some cases, ultimate eradication. These are located in the Pilbara (hybrid mesquite), southwest Queensland (Prosopis velutina), and Hughenden (P. pallida), McKinlay area ("hybrid" mesquite) and near Kynuna (P. pallida) in north Queensland.

This project is a continuation of an existing project (2004 - June 2007, funded through the cross-regional NHT program).

Aims:

This project aims to:

Test whether the invasiveness of mesquite, and its response to a range of management options, differs with taxa (species and hybrids) and climate (between regions and years), and how that might be affected by a range of landscape-scale ecological processes. The latter includes the distribution of suitable habitat across the landscape, land use history, and the presence, distribution and behaviour of potential dispersal agents (such as livestock, macropods, emus and flood water).
Develop recommendations from the research results as to how core mesquite infestations across Australia can best be managed using available management tools and within the context of the landscapes in which they occur. Importantly, they will consider the landscape-scale processes that determine patterns of dispersal, invasion and impact.

Developing a model for environmental weed management in fragmented landscapes: A case study

Mon, 18 Aug 2008 03:48:51 +0000

IDs and People

Program:

Defeating the Weed Menace R&D Program

Program Theme:

Weed management strategies that incorporate an understanding of landscape scale ecological processes

Research Type:

Research Project

Legacy (KMS) Project ID:

DEH9

Host Organisation:

Department for Environment and Heritage SA

Researchers:

Mark Bachmann

Subjects

Subjects:

Weeds

Keywords:

Developing new integrated weed management strategies that incorporate an understanding of landscape scale ecological processes

Project Information

Summary:

This project is focused on landscape scale weed management in South East South Australia. It is designed to test the scientific merit, acceptability and usefulness of a new integrated planning tool that takes account of the interactions of weeds and natural systems across entire landscapes. The management tool has been developed to assist in prioritising environmental weed management actions based on the risks posed.

Current Activities

Status:

Active

Background

Project Background:

Weed management strategies have traditionally focused on a single species approach which, when dealing with environmental weeds, ignores the complexity inherent in natural systems and the interactions of multiple weed species across a landscape. Effective treatment of environmental weeds requires an integrated approach which takes account of the interactions of weeds and natural systems across the entire landscape. The regional scale is typically used for NRM planning and yet few credible models can be found which can be used for environmental weed planning at this scale.

Aims:

The South East NRM board in cooperation with the Department for Environment and Heritage in South East South Australia have developed, over the past two years, a working model which prioritises environmental weed management across the region based on an assessment of the weed threat posed to individual patches of remnant vegetation.

The model also incorporates the biological and physical values of individual patches of vegetation to produce a final ranking of patches of remnant vegetation based on their value and the weed threat posed to them. This process has been tenure blind and is designed to allow resources for weed management to be allocated accurately to those areas of highest priority. This is essential for planning the allocation of scarce resources to achieve the best value for money.

This project will allow the concept to be broadened, incorporating the views of other practitioners in the field, and adapted to incorporate the characteristics of a range of other temperate landscapes. The end product will be a model which is detailed enough to be implemented in any temperate landscape, flexible enough to be adapted to differing priorities and which meets the needs of the full complement of end users.

Understanding and determining mechanisms to prevent weed invasion in coastal vegetation

Mon, 18 Aug 2008 02:32:25 +0000

IDs and People

Program:

Defeating the Weed Menace R&D Program

Program Theme:

Land use change impacts on weed incursion

Research Type:

Research Project

Legacy (KMS) Project ID:

UWO6

Host Organisation:

University of Wollongong

Researchers:

Assoc. Prof. Kristine French

Subjects

Subjects:

Data and Information

Weeds

Water (General)

Keywords:

Land use change impacts on weed incursion

Project Information

Summary:

By improving understanding of which types of land disturbance influence weed invasion and how weeds replace native species, this project will assist in designing management practices to restore native vegetation in coastal areas without the need for long-term maintenance.

Outcomes:

The project team found significant differences in resilience to bitou invasion by communities that contained different growth forms. Grass monoculture offered better resilience to bitou germination and establishment than the shrub monoculture, herb and shrub polyculture and priority effects polycultures.

Dense grass cover may more effectively suppress bitou germination than functionally diverse plantings, at least in the short term, but at the expense of biodiversity.

Current Activities

Status:

Complete

Background

Project Background:

While invasion of weeds into coastal communities appears associated with high levels of disturbance (both anthropogenic and natural), there is a current lack of knowledge of which types of disturbances influence invasibility and how weeds replace native species. If native coastal communities are to be protected from invasion and restore areas, it needs to be understood under what situations natural vegetation might prevent weeds from invading.

Aims:

The project seeks to investigate three mechanisms that our previous research has suggested are the likely causes of invasion: the loss of particular groups of native species (function groups), an increase in the weed native seed ratio available (propagule pressure) and the role of competitive interactions. These three are likely to form the key to developing management actions that protect coastal vegetation from invasion.

Currently, weed control measures lock land mangers into long-term maintenance programs which reduce weed biomass but do not produce resilient, sustainable native plant communities ie they treat the symptom, not the cause.

This project aims to identify the causes of invasion and is likely to primarily facilitate protection of native vegetation by providing knowledge of invasion that can be directly incorporated into management, as well as providing critical guidelines to restore native vegetation to a resilient form.

Actions such as replacement of critical species at sites, native seed loading of soil, and prioritising particular invasion foci can be evaluated effectively following this research. This project investigated both primary and secondary invaders as our work in coastal systems has found that removal of one weed enhances the invasibility of others. The project was set in a framework of coastal dune communities affected by the primary invader bitou bush (Chrysanthemoides monilifera ssp. rotundata) and secondary invaders such as lantana (Lantana camara) and asparagus fern (Asparagus aethiopicus).

Effect of land use and peri-urban development on aquatic weeds

Mon, 18 Aug 2008 02:25:21 +0000

IDs and People

Program:

Defeating the Weed Menace R&D Program

Program Theme:

Land use change impacts on weed incursion

Research Type:

Research Project

Legacy (KMS) Project ID:

CEN20

Host Organisation:

CSIRO Entomology

Researchers:

Dr Shon Schooler

Subjects

Subjects:

Data and Information

Weeds

Water (General)

Keywords:

Land use change impacts on weed incursion

Project Information

Summary:

We are interested in understanding the individual growth responses and competitive dynamics of native and invasive aquatic macrophytes in various environmental conditions. Before initiating a more complex study, we propose to evaluate the effects of a single factor, shading, on the growth of non-native aquatic macrophytes. This factor is relevant to the larger scope of our research, in which we are investigating the effects of peri-urban development on aquatic plant populations. Riparian clearing is common in urban and agricultural landscapes, and the resulting increase in light (and water temperature) may contribute to the proliferation of aquatic invaders. Indeed, other researchers have demonstrated the efficacy of shading in reducing populations of these species. We are interested in applying this question to three previously untested species and establishing the critical level of shading that limits their growth.

Outcomes:

Aquatic weed abundance was quantified according to land use through desktop and field-based surveys and classified 24 species in a ranked list based on distribution. Management efforts should be tailored to the relative distribution of these species, with recommendations for biocontrol of widespread species and focused early-detection programs for those currently classified as rare.

The land use types that hosted the greatest numbers of aquatic weed species were those that were classified as “urban” or “intensive” in this studies. Peri-urban land uses hosted an intermediate abundance of aquatic weed species in the field-based study, but evidence suggested weed species were better able to capitalise on peri-urban conditions than native aquatic species. Field-based and experimental work revealed that aquatic weed growth was inversely related to canopy cover and shade.

Two recommendations follow from the results of this project:

Land managers should focus their early-detection and control efforts on peri-urban and urban land use areas
Riparian forests should be restored to reduce light availability and buffer nutrient inputs, resulting in sustained reduction of aquatic weed populations.

Current Activities

Status:

Pending

Background

Project Background:

Peri-urban areas are expanding rapidly in Australia, and due to landscape modifications such as disturbance, increased nutrients and changes in hydrology and increased introduction of weed species, they are experiencing severe weed problems.

Weeds in waterways (aquatic weeds) are both a problem in their own right and as a source of introduction of weeds into previously pristine environments. Effective management of such species will require holistic management strategies across local landscapes.

This project will identify the environmental conditions and plant characteristics that drive weed invasion of aquatic systems, to assist in better managing introduced plants with potential to adversely affect our waterways in the future.

Aims:

The purpose of this project is to understand the impacts of peri-urban development on the invasiveness of aquatic weeds in Australia. This will be achieved by:

Quantifying the current aquatic weed problem in peri-urban environments (species, location, and abundance)
Determining to what extent aquatic weed problems are the consequence of introduction events (propagule pressure) and/or modified environmental factors (i.e. nutrient inputs, stream hydrodynamics, and riparian canopy structure)
Identifying methods to manage landscapes in order to reduce aquatic weed spread and impact.

Location

State & NRM Region:

National