Large scale trials of SIRA TAC comparing standard and dynamic thresholds were done for three years on commercial farms along the length of the Namoi valley. The results of these trials were integrated with data from CS16L and CS30L (The response of cotton crops to damage) and made available to the industry at the Australian Cotton Conference (Brook et 1986, Kelly et al 1988). Further analysis of these results shown that the capacity of the cotton crop to compensate for early season damage depends on the yield level. At yield levels common a decade or more ago (5 to 6 bales per ha) the crop could compensate but at current yield levels (7+ bales per ha) it is unable to do so. Furthermore Siokra is more tolerant to damage than DP90. These findings have been published in a series of three papers in the Journal of Economic Entomology (Brook et al 1992, in press) and received rave reviews from the cotton entomology community as one of the most thoroughly tested cotton pest management systems. The abstracts of these papers are attached.