In season 2001-02, the Central Highlands area

of experienced Australia's

first major outbreak of Silverleaf Whiteny

(Bentsi" tobcci biotype B) in a cotton

production system. The situation was managed

to some degree with existing products, and

whilst there is no indication that the quality of

Central Highlands cotton was diminished this

season, the industry realised that advances

needed to be made for the effective management

of this pest in the future.

Two key factors that made management of

Silverleaf Whitefly (SLW) difficult in 2001-02

were a lack of suitable insecticides and knowledge

of the pest and how it would react in cotton in the

Australian environment.

To address the second issue, the Cotton Research &

Development Corporation, Cotton Seed

Distributors, and the cotton grower associations of

the Central Highlands, Theodore and Biloela

sponsored 12 people involved in the cotton

industry in Central Queensland to visit regions in

the United States of America that had experienced

and managed problematic SLW populations.

Indigenous Law and cultural traditions remain strong and active in many parts of Australia. This project demonstrates a way for local Indigenous groups and other stakeholders to agree on the management of significant places and local issues with the aim of improving cultural and national heritage and Indigenous futures.

The objectives of the LWRRDC scoping review were: 1. To summarise wetland resources in general terms in Australia using existing information, and identify where information required for ecologically sustainable development is lacking. 2. To identify the key issues for wetlands management, within the context of overall natural resources management. 3. To identify and prioritise the generic, national or regional issues for which R&D investment could bring the greatest returns in terms of maximising national benefits. 4. To describe the current state of knowledge of the priority issues in a concise, well referenced format including the scale, impact, significance, costs, threats and opportunities. 5. To propose specific R&D requirements for each issue that will be sufficient to resolve the technical components of the problem. 6. To identify social, economic and policy impediments or constraints to resolving the priority issues and propose R&D or other projects that might assist in overcoming these impediments.

In this issue: Investigating the Salt of the Earth; Digging deep and the quest for super soils; Linking irrigator experience with measured data

This report describes a project undertaken to examine human perception of native vegetation. The project employed photo-questionnaire techniques designed for measuring psychological preferences, adapting these for the purpose of identifying attitudes that promote or hinder the protection of native vegetation. Landholders in south-eastern Australia and urban residents of Melbourne were surveyed to identify preferences for vegetation types.

Over the years a great deal of work has been directed towards improving the selection, testing and evaluation of biological control agents for weed control. This publication is one of a suite of 13 produced as part of a folder showcasing research from the Defeating the Weed Menace Research and Development program.

This edition of RipRap looks at the benefits that landholders can gain from managing their riparian zones as part of a total farm system. It also examines the work that is being done by Gary Brierley and Kirstie Fryirs on identifying the 'recovery potential' of a particular reach of river or stream. This work enables us to focus attention on those parts of the river and riparian zone that will respond best to rehabilitation activities. The result is that Gary and Kirstie's work can be used by landholders to identify and develop cost-effective river and riparian management strategies that will reap optimum ecological and economic benefits.

This fact sheet summarises the work Dr John K. Scott and his colleagues have completed using computer modelling of both plant characteristics and global climate change to predict how 41 of the nationally recognised 'environmental alert' species and agricultural 'sleeper weeds' are likely to behave as the effects of human-induced climate change become more apparent. It is now scientifically accepted that Australia's climate is changing and that these changes will continue over coming decades. Some weeds previously identified as either agricultural 'sleeper weeds' or weeds on 'environmental alert'* are likely to spread as a result of these changes in climate. This publication is one of a suite of 13 produced as part of a folder showcasing research from the Defeating the Weed Menace Research and Development program.

This update outlines design criteria for filter strip width to trap sediment and attached nutrients, and to accommodate typical soil losses from hill slopes.

The potential contribution of surface and ground water to overall nitrous oxide emissions from irrigated production systems has not yet been quantified. In this study we have used the International Panel on Climate Change (IPPC) emission factor five (EF5) to determine the indirect emissions from the irrigation water surface and from the ground water when it is pumped back onto the surface for irrigation. The additional land surface emission from the irrigation water source N was also calculated and termed the “indirect land surface emission”. The study primarily used data collected (2000–2010) from the Australian Cotton Research Institute, Narrabri, Australia to calculate indirect and direct farm emissions during the cotton production season from the research station. The average annual direct and indirect N2O-N emissions are 0.90 kg N2O-N ha−1 yr−1 direct; 0.30 kg N2O-N ha−1 yr−1 indirect emissions from the land surface; 0.08kg N2O-N ha−1 yr−1 from the head ditch; 0.03 kg N2O-N yr−1 from the tail drain. In total 26% of the emissions could be potentially emitted via the indirect pathway at the farm scale using river water for irrigation. If ground water with a concentration of (1.0 NO3-N mg L−1) was used to irrigate the crop then in total ∼1.4% of the emissions would be emitted via the indirect pathway at the farm scale. But further refinement of the indirect emission factor and improved monitoring of temporal and spatial surface and ground water total N concentrations are required for mass balance calculations. Direct measurement of the N2O-N water surface emissions is required to validate the IPCC calculated values