During 1997/98, a postal survey of 100 sheep and beef pastoral farms asked the farmers a range of questions based around pasture performance and their perceptions on persistence, and asked them to identify a persistent paddock on their farm. The farmers were then interviewed on the management of the chosen persistent paddock and the paddock was assessed for composition and fertility. The farmers ranked pasture species persistence fourth, behind pasture quality, animal health, and soil fertility in terms of importance to the whole farm system. The difference was significant between pasture quality and pasture persistence. The persistent pastures, as identified by the farmers, had high levels of desirable species and low levels of weeds and low-fertility volunteer species. The survey showed some pastures can persist and maintain high levels of desirable species for periods over 21 years. Fertility is a key factor in pasture persistence followed by drainage and grazing management. Keywords: farm management, farm survey, farmers' perceptions, interview, pasture persistence, species composition, soil fertility
The purpose of the present paper is to determine the effect of the Ca‐Mg ratio in solution and in the soil on the solubility and availability of certain plant nutrients. In recent years many papers have been published on the effect of the Ca‐Mg ratio on crop production. Certain papers and unpublished data have indicated that the Ca‐Mg ratio affects the solubility of other plant nutrients, esepecially phosphorus, including some of the minor or trace elements. Nutrient solutions have been made up and mixed with common soil clay kaolin as an adsorbing component. The solubility of B, Mn, Zn, Cu, K, and P were determined. Soil from the Kingman area which is quite low in Mg was obtained for greenhouse studies. Wheat and sorghum were grown and analyzed for the above elements. Plant uptake of the nutrients was plotted against the Ca‐Mg ratio. The results showed:
A varying Ca:Mg ratio in Kingman soil produced a difference in the weight and height of the plants grown with a maximum plant growth at a Ca‐Mg mol. ratio of 4‐1. All the nutrient elements studied were affected by a varying Ca:Mg ratio in the soil.
The effects observed on the minor elements in wheat and sorghum agree qualitatively with most of the effects observed in nutrient solution studies.
No direct correlation was found between the ratio of Ca:Mg in the soil as compared to the ratio in the plants, but a general correlation occurs.
An overall maximum uptake of the minor elements seems to be provided for both wheat and sorghum at a Ca:Mg ratio of approximately 4:1.
A high magnesium soil favors the uptake of Mn and Zn by sorghum and K, B, and Mn by wheat.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.