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Atmospheric [CO.sub.2] and temperature may significantly modify plant production. Grasslands occupy in excess of 25% of the Earth's land area, but grassland species have received limited attention from researchers studying climate change. A 3-yr study was conducted to determine the effects of elevated atmospheric [CO.sub.2] and temperature on dry matter (DM) harvested from the [C.sub.3] legume `Florigraze' rhizoma peanut (RP, Arachis glabrata Benth.) and the Ca grass `Pensacola' bahiagrass (BG, Paspalum notatum Flugge). Both species were field grown in Millhopper fine sand (loamy siliceous Grossarenic Paleudult) in temperature-gradient greenhouses under different [CO.sub.2] (360 and 700 µmol [mol.sup.-1]) and temperature conditions (baseline [B], B+1.5, B+3.0, and B+4.5 ° C, where B equaled ambient temperature). Plots (2 by 5 m) were harvested three times in 1996 and four times each in 1997 and 1998. Analyzed across years, yield increased 25% for RP (P = 0.02) and tended to increase for BG (15%; P = 0.18) with the near doubling of [CO.sub.2], but there was species by [CO.sub.2] interaction (P = 0.06) as a result of the greater response to [CO.sub.2] by the [C.sub.3] legume. There was a positive effect of increasing temperature on yield of both species. Averaged across species, yield increased 11% in 1996, 12% in 1997, and 26% in 1998 as temperature increased from B to B+4.5 ° C. Under well-watered conditions in this experiment, elevated [CO.sub.2] increased DM harvested of a [C.sub.3] legume and tended to increase that of a [C.sub.4] grass, while the yield response to increasing temperature was positive for both species., ATMOSPHERIC [CO.sub.2] has steadily increased from preindustrial concentrations of 280 µmol [mol.sup.-1] and is predicted to double by the end of the 21st century (Barnola et al., 1994; Keeling and [...]

'Tifton 85' bermudagrass [Cynodon dactylon (L.) Pers. × C. transvaalensis Burtt Davy] is a highly productive warm-season grass, but it must be planted vegetatively using aboveground stems (stolons) or rhizomes. Use of stolons vs. rhizomes provides advantages of reduced cost, greater shoot production, and more planted area per hectare of nursery. However, establishment failures have been reported by producers under challenging environmental conditions common to the Coastal Plain region of the southeastern United States. Thus, strategies for harvesting and planting stolons need to be evaluated further. The objective was to assess the effect of stolon type (length and stolon position) and degree of stolon burial by soil (total or partial) at planting on Tifton 85 bermudagrass establishment. Partial burial of stolons at planting accelerated emergence and increased bermudagrass percentage cover and dry matter harvested at season end. Total burial resulted in only half as many shoots (3.5 vs. 7.8 m-2) as partial burial in 2011; total burial resulted in no emergence in 2012. Partial burial led to as much as 90% bermudagrass soil cover, while total burial provided 66 and 0% in 2011 and 2012, respectively. Also, partially buried stolons yielded 1000 kg ha-1 of forage more than totally buried in both years. This finding suggests the planting equipment should be set to achieve shallow planting, ensuring that some parts of the stolons remain uncovered. Stolon type is not as critical as the degree of soil cover on the stolons, which need to remain only partially but not totally buried. [ABSTRACT FROM AUTHOR]