Yields, Stand Persistence, and Carbohydrate Reserves of Perennial Grasses as Influenced by Spring Harvest Stage, Stubble Height, and Nitrogen Fertilization¹

Abstract

Spring harvests of orchardgrass, bromegrass, and reed canarygrass were made at pre‐joint, early head, early bloom, and late bloom. At least one aftermath was differentially cut leaving either a 1.5‐ or a 3.5‐inch stubble. Nitrogen was applied at either 25 or 75 pounds N per acre per harvest. Yields increased with maturity at harvest. Greatest persistence with least weed encroachment was obtained at late bloom. The effects of stubble height varied with species, harvest date, and nitrogen rate. Yields were increased with high nitrogen even though stand was reduced. Although a negative relation existed between fructose and aftermath forage production, total fructose was positively correlated with etiolated tiller growth.

Ecology and Evolutionary Biology of Clonal Plants

“…Out of about 150 to 200 species of vascular plants which usually occur together in individual localities of species-rich meadows, there are very few plants, usually grasses, which become dominants after regular management ceases. Fertilization may result in effects similar to those observed in abandoned meadows: more nutrients are available, species richness declines and a single grass species becomes dominant (Rease and Decker, 1966).…”

“…The total amount of carbohydrates per plant is higher in species developing storage organs. The importance of carbohydrate storage has repeatedly been demonstrated in various species, especially for regeneration after cutting (Hogg and Lieffers, 1991a, b;Klimesova, 1996;Donaghy and Fulkerson, 1998) and for spring regrowth (Rease and Decker, 1966;Clevering et af., 1995). However, little is known about differences between species in the amount of carbohydrates available for regeneration after a disturbance, within a stand or a plant assemblage.…”

Assessing eight grass species for pasture by measuring etiolated spring regrowth

“…Etiolated regrowth measured in the field can be used as a quantitative index of stored carbohydrate reserves of plants prior to spring growth (MacLeod 1965;McKendrick and Sharp 1970). Raese and Decker (1966) indicated a positive correlation (P < 0.05) between total non-structural carbohydrates and etiolated growth for orchardgrass, smooth bromegrass and reed canarygrass.…”

Regrowth of smooth bromegrass (Bromus inermis Leyss.) following defoliation

“…In past studies, yield, tiller densities, carbohydrate status and ground cover of smooth bromegrass were determined at a single predetermined time following defoliation (Reynolds and Smith 1962: Raese and Decker 1966;Smith 1968, 1969). Levels of soluble carbohydrates and the quantity of regrowth appear poorly correlated for smooth bromegrass (Reynolds and Smith 1962;Paulsen and Smith 1969 (Looman 1983).…”

“…Growth of axillary tillers depends on moisrure, temperature (Morrow and Power 1979) and available nitrogen (Raese and Decker 1966 In 1989-1990 and 1990-1991, total precipitation was24 and 67% greater than the long-term average, respectively, but it was only 2% above average in [1991][1992] (Fig.2) Winter survival of fall tillers was greatest when plants were defoliated in July and lowest if herbage was removed in late May or June (Table 3) In the 1991 study, an average of 871 + 100 tillers m-2 were living in May 1992, and densities were not different (P > 0.05) among treatments. An average of 5O-70% of the tillers were produced the spring following defoliation (Fig.…”