HWSC systems that target weed seed production during harvest have been in use in Australian crop production systems for over 30 years. Until recently, though, grower adoption of these systems has been relatively low. It is now apparent with the introduction of a range of new weed seed targeting systems that there is renewed grower interest in the use of this approach to weed control. With the aim of determining the current adoption and use of HWSC systems, 600 crop producers from throughout Australia’s cropping regions were interviewed on their adoption and use of these systems. This survey established that 43% of Australian growers are now routinely using HWSC to target weed seed production during grain harvest. The adoption of narrow-windrow burning (30%) was considerably greater than the other currently available techniques of chaff tramlining (7%), chaff carts (3%), bale-direct system (3%), and the Harrington Seed Destructor (HSD) (<1%). When growers were asked about their future use of these systems 82% indicated that they would be using some form of HWSC within five years. Grower preferences for future HWSC use were primarily for either narrow-windrow burning (42%) or the HSD (29%). This very high level of current and potential HWSC adoption signifies that HWSC is now considered an established weed control practice by Australian growers.

In most world crop-production areas, the evolution of herbicide-resistant weeds is becoming a major issue. This problem has become most severe across the Australian dryland crop-production region, where herbicide-resistant weed populations are threatening crop-production profitability and sustainability across 20 million ha. Widespread herbicide resistance has forced changes in agronomic and herbicide practices. This problem is particularly evident in Western Australia, where the frequency and distribution of herbicide-resistant weed populations appear to be greater than anywhere else in the world. Judicious use of herbicide mixtures and rotations can reduce the selection pressure for evolved resistance to any one specific herbicide. Additionally, agronomic practices, such as the double knockdown (preseeding sequential application of nonselective herbicides), increased seeding rates, and targeting of weed seed production to prevent seedbank inputs, are needed to reduce the selection pressure on all herbicides by reducing in-crop weed populations. However, these techniques are not without problems or limitations, and their weed control efficacy is inferior to that of most in-crop selective herbicides. The adoption by Australian farmers of the current limited technology is clear evidence of the value placed on the use of these alternate crop weed-control practices. The continued evolution of herbicide resistance more than justifies continuing research and development efforts to produce integrated strategies and smarter herbicide use so as to achieve sustainable weed management.