Frogeye leaf spot of soybean is caused by the fungus Cercospora sojina. The disease occurs across the United States and in Ontario, Canada. This publication describes the symptoms of frogeye leaf spot and conditions favorable for the disease. We also point out how frogeye leaf spot differs from several other soybean diseases and disorders and suggest management practices.

A field study was conducted in a saltgrass (Distichlis stricta) meadow at the Central Plains Experimental Range to investigate relationships between soil types, salinity, sodicity, fertility, and vegetation ground cover and species composition. Three line transects that included 48 soil cores and their adjacent vegetation cover were sampled. Soils data indicated relatively good homogeneity between transect 1 and 3 with transect 2 exhibiting the poorest soil physical characteristics because of shallow A horizon and high sodium. Species composition averaged across transects reflected in general the following magnitude of ground cover distribution over the 1979-1983 seasons: blue grama (Boureloua gracilis) > alkali sacaton (Sporobolus airoides) > saltgrass > western wheatgrass (Agropyron smith+. Species nutrient concentration data showed western wheatgrass with the highest concentration of N and K, alkali sacaton highest in P, Ca, Mg, and Na. Saltgrass was assimilating primary NaCl and alkali sacaton NazS04. Blue grama showed low Na and Cl concentrations, which suggested a superficial rooting pattern above the saline horizons. Plant-soil correlations for all transects are discussed.

Establishment of grass species used in range reseeding should improve if germination time can be decreased. Osmotically controlling the hydration of seed so that germination processes proceed other than radicle emergence (osmoconditioning) can decrease germination time of many plant species. Growth chamber esperiments were conducted to evaluate effects of osmoconditioning at -1.5, -2.0, and -2.5 hlpa for 4,8,12,16, and 20 days on germination and root growth of 'Flintlock' western wheatgrass (Pascopyrum smithii (Rydb.) A. Li5ve) and 'Vinall' Russian wildrye (Psathyrostuchys juncea (Fischer) Nevski) and at -2.0, -2.5, and -3.0 hWa for 4, 8, 12, 16, and 20 days on 'Nordan' Crested wheatgrass (Agropyron desertorum (L.) Gaertn.) and 'Tegmar' intermediate wheatgrass (Agropyron intermedium (Host) Beauv.). A second study looked at germination time of seed from the same species conditioned at osmotic potentials and durations producing the shortest time to 50% germination (optimum conditioning) and air dried for 0, 1, or 7 days. Conditioned seed of Russian wildrye and western wheatgrass germinated 2 to 4 days faster, respectively than untreated seed. Optimum conditioning of seed from all 4 species produced seedlings with roots 20 to 67% shorter 4 days after germination than seedlings from untreated seed. Conditioned western wheatgrass seed continued to germinate faster than untreated seed after being air dried for 7 days. Slow root growth from conditioned seed may negate any benefits derived from rapid germination.

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Plains pricklypear cactus (Opunti polyacantha L.) is abundant on the Central Great Plains, producing dry matter yields from l,!%O tu 2,000 kg/ha. Although pricklypear is high in energy and palatable, long sharp spines make it, and vegetation immediately surruunding it, unavailable to livestock. The possibility of simultaneously controlling and feeding plains pricklypear led to development of machinery for harvesting and despining cactus. The mechanical despiner described here adequately removed spines fern pads during periods of low relative humidity. Softening of cactus spines due to high relative humidity resulted in failure of the despiner to adequately remove spines. Cattle readily ate despined cactus in the winter when green forage was unavailable.