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Sticky florestina (Florestina tripteris DC.) is an annual exotic weed that has become naturalised near the townships of Tambo and Barcaldine in central western Queensland, Australia. Three experiments conducted near Barcaldine identified foliar herbicides effective in killing sticky florestina plants and in providing residual activity to reduce recruitment from the soil seed bank. An initial chemical screening experiment evaluated the efficacy of 28 herbicide treatments. The most promising herbicides were then further evaluated in two response-rate experiments. Overall, 2,4-D/picloram, aminopyralid/fluroxypyr, clopyralid, metsulfuron-methyl and triclopyr/picloram proved to be the most effective selective herbicides. Two of these, metsulfuron-methyl at 18 g active ingredient (a.i) ha–1 and 2,4-D + picloram at 900 g a.i. ha–1 + 225 g a.i. ha–1 have now been included in a minor use permit (PER11920) with the Australian Pesticides and Veterinary Medicines Authority (APVMA) for the control of sticky florestina in pasture, stock route, roadside and non-crop situations using both spot and boom-spray applications (APVMA 2010). The permit also allows the use of 2,4-D amine for the control of seedlings only.

Age-class frequency distributions are valuable means of describing plant populations because they can be used to infer population history. Variables other than age are also often used to describe plant populations, either because they more accurately reflect an attribute of interest, or because it is difficult to determine age. However, interpretation of frequency distributions based on variables other than age can be problematic. We discuss these problems and illustrate them using data from six populations of the invasive rangeland shrub Parkinsonia aculeata L. We used three different measures of plant size: height, canopy diameter and stem cross-sectional area. Structures based on these measures were compared with structures based on three different estimates of above-ground biomass derived from them. For each variable, structures differed greatly between populations, and for each population, they were strongly dependent on the variable used to describe it. Population structures based on three-dimensional variables (above-ground biomass) tend to be more strongly positively skewed than those based on two-dimensional (area) measures of plant size. These in turn are more strongly positively skewed than those based on one-dimensional (height, diameter) measures. The statistical basis of this general phenomenon is discussed. The results highlight the difficulties of deriving histories and projecting futures of populations from size-class frequency distributions without accompanying knowledge of the temporal patterns of change in size variables as plants grow.

Parkinsonia aculeata is an invasive, introduced shrub that is found in all mainland states of Australia except Victoria. It is especially prevalent north of the tropic of Capricorn. Size-biomass relationships were established for this species using data from 167 shrubs spread across eight sites in the Northern Territory and north-eastern Queensland. Above-ground dry weight (W, kg) can be predicted from plant height (H, m), canopy diameter (D, m) or stem cross-sectional area (A, cm2) using the equations: W = 0.025 H4.47 W = 0.091 D3.64 W = 0.022 A1.61 These relationships are linear when plotted on log-log scales. Although there was a significant effect of "site" on the log-log relationships between above-ground dry weight and size variables, the amount of information lost by not using site-specific equations is relatively small. These results provide reliable methods for estimating above-ground biomass in this species, the most robust being based on measurements of stem diameter at 20 cm above ground level.

The effects of regular implantation of 36 mg zeranol on behaviour, growth rate, and carcass characteristics of young Friesian bulls grazing grass pastures in New Zealand were evaluated. The trial, involving 206 bulls, compared 2 implanting intervals of 70 days and 105 days with untreated controls over a 420 day period, starting at an average weaning age of 12 weeks. A newly developed objective assessment of behaviour (RYDER score) demonstrated (P

Managers of going grocery and similar products usually are provided with adequate information about consumer sales by retail audits and consumer panels. Standard reports of consumer panels indicate, basically, the proportion who purchase the brand at all during period reported-usually four weeks-and the amount purchased (usually for convenience in raised figures) during that period. But managers of new products require additional information; it is not enough for them to know the proportion purchasing, and total consumer sales during successive periods because a given volume of consumer sales can mean either that relatively few households are purchasing frequently or that relatively many have tried and few if any are repeating. Each situation calls for different-and prompt-action, so the sooner the situation is diagnosed the better. A customary method of diagnosis is the buying study. A buying study is a particular analysis of consumer panel data. Whereas standard reports report the panel in total, a buying study reports each and every household's purchasing individually. By this means the trial level (proportion of total panel who have made at least one purchase of the brand) can be plotted progressively. A characteristic of many consumer panels is that they underreport. Underreporting arises simply from the human frailty of forgetfulness. But because the bias arising from underreporting is relatively stable it does not invalidate trends. Thus reports of going products still provide useful marketing data. But in the case of buying studies where trial level is of paramount importance, the situation is very different. Because some housewives who have purchased on

Results of a survey of attitudes toward a range of potential new products are analyzed to detect interviewer effects by means of a nested random effects analysis of variance model. The relationship of such effects to interviewers’ views on the products and to question content also is investigated.