In several European nations, including France and Germany, atrazine has been banned because of environmental concerns. However, in Canada, atrazine remains an important component of modern weed control in corn. The objectives of this study were to determine the value of atrazine to corn producers by examining weed control efficacy, yield of corn, adjusted gross return, and the variability associated with PRE and POST herbicides applied alone or in combination with atrazine. A randomized complete-block design experiment was conducted at two locations for 3 yr to evaluate the performance of selected PRE and POST herbicides with and without atrazine. The addition of atrazine to PRE herbicides increased weed control (25%), improved herbicide performance consistency, increased corn yields (8%), increased adjusted gross return (Can$59 ha−1), and reduced risk ($30 ha−1) over sites and years. Although improving weed control, the addition of atrazine to POST herbicides increased the risk of return compared with treatments without atrazine by about $20 ha−1 because the increased cost of atrazine was not always offset by higher corn yields. Our results clearly demonstrate a value of atrazine for broadleaf weed control in corn, both in terms of efficacy and economic return. From our findings, we estimated that the economic benefit of atrazine to Ontario, Canada, corn producers to be at least $26.1 million in 2004. Under current economic pressures facing agricultural producers, our findings show that a balance between the environmental effects and the benefits of atrazine to corn producers must be found because no alternative herbicide with equal economic and agronomic attributes is available at this time. To meet this balance, research on further reducing atrazine use rates while maintaining effective weed control in corn and on developing a sustainable stewardship plan is warranted.

Hydraulic fracturing (HF) is a focal topic in discussions about domestic energy production, yet the American public is largely unfamiliar and undecided about the practice. This study sheds light on how individuals may come to understand hydraulic fracturing as this unconventional production technology becomes more prominent in the United States. For the study, a thorough search of HF photographs was performed, and a systematic evaluation of 40 images using an online experimental design involving $N=250$ participants was conducted. Key indicators of hydraulic fracturing support and beliefs were identified. Participants showed diversity in their support for the practice, with 47 percent expressing low support, 22 percent high support, and 31 percent undecided. Support for HF was positively associated with beliefs that hydraulic fracturing is primarily an economic issue and negatively associated with beliefs that it is an environmental issue. Level of support was also investigated as a perceptual filter that facilitates biased issue perceptions and affective evaluations of economic benefit and environmental cost frames presented in visual content of hydraulic fracturing. Results suggested an interactive relationship between visual framing and level of support, pointing to a substantial barrier to common understanding about the issue that strategic communicators should consider.

The objective of the study was to test the effect of a direct fed microbial (DFM) on the performance of broilers compared to an antibiotic growth promoter under large scale, commercial production settings. Three dietary treatments were tested in a completely randomized design including: 1) a control (C) diet containing 500 FTU/kg phytase and a mixture of xylanase, amylase, protease ; 2) C+ a specific three-strain combination of Bacillus spp. (DFM) and 3) C+ bacitracin methylene disalicylate (BMD). Six, similar commercial broiler houses (15,300 birds per house) were used to give two replicate houses per treatment. The birds (Hubbard x Cobb500) were fed pelleted and crumbled diets ad libitum throughout the 44 day trial period. Due to the large scale, commercial nature of the trial, no significant differences were observed in production parameters among treatments, except that DFM treatment resulted in significantly lower mortality numbers in the last two days (43 to 44d) compared to the control. However, the DFM treatment group showed numerically higher live bodyweight, lower feed conversion ratio (corrected for body weight and mortality) and lower total mortality weight compared to either the control or BMD groups, resulting in an improved production efficiency factor. When compared to control, using DFM resulted in a gross benefit of US$ 0.06 /bird, while using BMD was not cost effective. In conclusion, DFM containing a three-strain combination of Bacillus spp. may be used as an alternative to antibiotic growth promoters, resulting in economic benefit under commercial production settings in broilers fed commercial diets.