Warm‐Season Grass Diversity in Yield, Plant Morphology, and Nitrogen Concentration and Removal in Northeastern USA

Abstract

Six genera of warm‐season grasses were grown in Pennsylvania for 9 yr on a fine‐loamy, mixed mesic, Aquic Fragiudult, to determine their potential as forage grasses on droughty sites. Effects of applied N on yield, plant morphology, and N composition of forages were studied during Years 4 through 7, when N was applied to half of each plot area. Big bluestem, Andropogon gerardii Vitman, and switchgrass, Panicum virgatum L., showed much cultivar variation in stand development, whereas asiatic bluestem, Bothriochloa spp., and indiangrass, Sorghastrum nutans (L.) Nash, developed productive stands in one season. Mean yield of ‘NJ 50’ switchgrass was higher than that of all other grasses, yield of ‘Niagara’ big bluestem was higher than that of other big bluestems, and yield of ‘Ky 591’ indiangrass was higher than that of other indiangrasses. The percentage of grasses showing a yield response to applied N increased each year, from 32% in 1981 to 67% in 1984. Mean yield response to N varied greatly among cultivars, P < 0.001. Nitrogen concentration in forage varied among bluestems and indiangrasses, but not among switchgrasses. Mean N removed in first‐harvest forage ranged from 16 kg ha−1 yr−1 for untreated ‘Plains’ asiatic bluestem to 97 kg ha−1 yr−1 for N‐treated NJ 50 switchgrass. Flowerstem density and height were affected differently by N, depending upon plant species and cultivar. The sheath‐stem component of dry matter yield was 60 g kg−1 higher when N was applied than when no N was applied. In the ninth year, approximately one‐half of the cultivars had stand ratings exceeding 80% ground cover.

Growth and cadmium accumulation in selected switchgrass cultivars

“…Three seeds of four switchgrass cultivars ('Alamo', 'Blackwell', 'Cave-in-Rock', and 'Trailblazer') were planted in 4x21-cm Conetainers (Stuewe and Sons, Portland, OR) containing acid-washed blasting sand. Alamo and Cavein-Rock were selected because they are high yielding cultivars in southern and northern trials, respectively (George and Obermann, 1989;Jung et al, 1990;Ocumpaugh et al, 1997;Stout, 1992). Blackwell was selected because it is a readily available variety and Trailblazer because it was developed for improved forage quality (Vogel et al, 1991).…”

Nitrogen Application Rate and Genotype Effects on Switchgrass Production and Chemical Characteristics

“…Jung et al [20] reported that N removal increased by 69% with application of N from 0 (48.8 kg•ha −1 ) to 75 kg•ha −1 (81.88 kg•ha −1 ) and this difference was related to biomass yield and tissue N concentration. For Alamo, NF/GA001, and NF/GA992, N removal was 112% greater than that of Cave-in-Rock (Figure 2).…”

Molecular Markers for the Classification of Switchgrass (Panicum virgatum L.) Germplasm and to Assess Genetic Diversity in Three Synthetic Switchgrass Populations

“…Switchgrass or tall panic grass (Panicum virgatum L.) belongs to the Paniceae tribe in the subfamily grazing and soil conservation (Vogel et al 1985;Jung et al 1990). The Bioenergy Feedstock Development Program (BFDP) at the US Department of Energy has chosen switchgrass as a model bioenergy species from which renewable sources of transportation fuel and biomass-generated electricity could be derived (Sanderson et al 1996).…”