Deep drainage (DD), defined as water that passes beyond the root zone, can be an important contributor in terms of recharging ground water and also in transporting certain amounts of soluble salts away from the principal root zone. As such, DD is not necessarily an adverse component in the soil or landscape water balance. However, excessive DD is not only economically poor practice but may also lead to rising ground water tables and increased solute concentrations elsewhere in the landscape. The Australian cotton industry has become increasingly aware of the large amount of deep drainage (DD) in many of the heavy textured soils (Vertosols) that are flood irrigated (Silburn et al., 2004). This information contradicted earlier beliefs in the cotton industry that 'clay soils don't drain' (Hearn, 1998). A review by Silburn and Montgomery (2003) was instrumental in helping the industry change their view of "leak proof" Vertosols, though work by Dalton (2003) stated that 'deep drainage in surface irrigated cotton systems has remained a contentious issue and one that has not been well understood or grasped by the Industry'. Seasonal deep drainage values under irrigated cotton of 100 mm and 200 mm have been calculated using volume balance measurements (Dalton, 2003), and Gordon (2000) measured seasonal deep drainage (using a large lysimeter) of 95 to 305 mm/year under drip irrigation and 165 to 180 mm/year under furrow irrigation on the Darling Downs, Queensland

The Cotton Best Management Practice (BMP) program was first introduced in 1997 to address negative public opinion of the industry and chemical contamination issues. Over the years the program has broadened to include other areas of farm management such as water, disease management, petrochemical management, soils, vegetation and riparian management.

This paper describes a method that can be used by individual cotton growers and/or cotton consultants to estimate the potential deep drainage. To do this the initial work undertaken was to identify the minimum number of observations that need to be taken to in a cotton field to give a good estimate the potential deep drainage (Figure 1). Once the number of observations needed was known the next stage involved estimating the sub-soil hydraulic conductivity using the falling head lined-borehole technique (FHLBT). To calculate the potential deep drainage also requires an estimate of how many days the sub-soil is saturated for, which growers can determine by knowing the soil moisture after irrigation using their C-probe data (Figure 1). The data generated by the growers is managed by the user-friendly Potential and Required Deep Drainage Interface housed in Microsoft EXCEL. To make the estimate of potential deep drainage more meaningful growers are also asked about the quality of their irrigation water and the crops that are to be grown during the season. This information is used to by the Potential and Required Deep Drainage Interface to determine the leaching requirement that is needed to prevent excess salts build up in the sub-soil that may affect crop yield.

This paper summarises the findings of a scoping study into the coordination of natural resource management (NRM) policy in the cotton industry, an industry which leads voluntarist environmentally adaptive farming systems in Australia. Interviews elicited assessments of the degree of NRM policy coordination in the cotton industry, as well as cotton growers' perceptions of current NRM policy, from professionals located within the cotton industry, Natural Resource Management Authorities, State and Local Governments. Interest among interviewees in the potential of co-regulatory arrangements to improve NRM policy coordination was identified. The advantages of co-regulatory arrangements for cotton growers, industry bodies and State Governments are discussed

The purpose of this paper is to provide an overview of the soil biology and what we know about its role within the cotton production system. Some of these issues fall under the concept of soil health, which we will briefly discuss. However, our mandate here is to focus on the soil biology, its ecology and responsiveness to cotton production management options. In order to achieve this we present a brief overview of components of soil biology, the impact of management upon them and what the future might promise.

In keeping with the cotton industry's mantra of "Concentrate on the things you can change and forget about the rest", I will outline the important parameters you can alter during design to optimize the overall performance of CP&LMs. This paper will examine the optimal design, installation and management of Centre Pivot and Lateral Moves or overhead irrigation systems. Topics will include optimizing the design to achieve an adequate system capacity or water supply rate, designs to minimize energy and labour inputs, and design to maximise the irrigation performance of CP&LMs in terms of uniformity and application efficiency. Discussion will follow on a range of recently completed tools that will assist surface irrigation growers and agronomists to more easily understand the practice of irrigation under CP&LMs.

Every incident of spray drift that has occurred in our cotton growing areas has one common factor - an error in the judgment made by the applicator. If applicators had appropriate knowledge of nozzle outputs, droplet behaviour and the influence of weather, then planned and conducted their sprays accordingly, spray drift could be eliminated.

Staff of the NSW Department of Primary Industries, Cotton Seed Distributors Ltd. and the Queensland Department of Primary Industries and Fisheries annually survey the distribution, incidence and severity of diseases in commercial cotton crops in all production areas of Eastern Australia. The results of these surveys provide an invaluable guide for planning and evaluating pathology research.

The critical period for weed control is a concept designed to optimise weed management and herbicide use in systems reliant on post emergent herbicides for weed control and is particularly useful in systems into which herbicide tolerant crops have been introduced

In the 1996/97 season the Australian industry adopted an insect-resistant variety of cotton (INGARD) that is specific to the group of insects including the target pests Helicoverpa armigera and H. punctigera but excluding natural predators and parasitoids. To prolong the efficacy of transgenic cotton against Helicoverpa species, a resistance management plan (RMP) was implemented. This plan was largely based on information from studies of the ecology and population genetics of H. armigera, and the outputs of computer simulation models that used biological information to predict the likelihood of resistance under different scenarios.