Cattle and sheep grazed together and separately from April to October during 3 yr. Initial forage composition was 29% Kentucky bluegrass (Poa pratensis L.), 11% white clover (Trifolium repens L.), and 60% weeds. There were six Angus cow-calf pairs or six ewes (1/2 Dorset x 1/4 Finn x 1/4 Rambouillet) with 11 lambs per each of three pasture replications for single animal species. Six cow-calf pa...

Action spectra were measured for suppression of germination of Poa pratensis L. and Amaranthus arenicola I. M. Johnston seed under prolonged or continuous irradiation. The action maxima for both types of seeds are near 720 nm. The maxima are unchanged in position or magnitude in the presence of radiation in the region of 600 to 670 nm adequate to maintain phytochrome predominantly in the far-re...

Phytoremediation efficiency mainly depends upon mechanisms in the uptake and translocation of soil contaminants. Cadmium (Cd) distribution and translocation in roots and shoots of tall fescue (Festuca arundinacea) and Kentucky bluegrass (Poa pratensis) were observed using fluorescence spectroscopy with a laser confocal scanning microscope. No difference in root Cd accumulations was detected bet...

The effects of temperature on population development of 11 species of stunt nematodes in the subfamily Tylenchorhynchinae were compared on red clover or Kentucky bluegrass in constant-temperature tanks at 5-degree intervals from 10 to 35 C. The optimum temperature for population increase on red clover in 90 days was 30 C for Tylenchorhynchus agri, T. nudus, T. martini, and T. clarus, 25 C for T...

Leaf slices of the sethoxydim sensitive grasses Poa pratensis and Festuca ovina and the sethoxy­ dim resistant grasses Poa annua and Festuca rubra take up the herbicide at similar rates. Uptake is almost linear with concentration up to 2 m M , independent of light and little affected by tempera­ ture between 0 and 25 °C. Uptake is highly pH sensitive. At pH 7.0 rates o f uptake are only about 2...

The fall armyworm Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), is a destructive pest of many species of both C3 and C4 (cooland warm-season) turfgrass. No-choice experiments were conducted to evaluate 13 turfgrass genotypes of various Poa spp. for susceptibility or resistance to the fall armyworm. All 13 genotypes, including 8 Texas bluegrass ( Poa arachnifera Torr.), 2 Kentuck...

We examined how elevated atmospheric [CO2] and higher rate of nitrogen (N) input may influence grasshopper growth by changing food plant quality and how such effects may be modified by species diversity of the plant community. We reared grasshopper nymphs (Melanoplus femurrubrum) on Poa pratensis from field-grown monocultures or polycultures (16 species) that were subjected to either ambient or...

A field study was conducted to evaluate two CDC gravid trap attractants available for the West Nile virus surveillance program in New York State (NYS). According to potential attractiveness, a common lawn sod in NYS, Kentucky bluegrass (Poa pratensis) infusion and a rabbit chow infusion were compared for attractiveness to primary West Nile virus vectors, Culex mosquitoes. Attractiveness of each...

Photomorphogenic light definitions were derived by mathematical determination of the estimated phytochrome photoequilibrium for each light treatment spectrum. A wide range of photomorphogenic light treatments represented by spectra with estimated phytochrome photoequilibria of 0.45, 0.54, 0.60, 0.67, and 0.71 was utilized to determine the influence of photomorphogenically defined light on resis...