Rk. Heitschmidt et al., STEER PERFORMANCE ON NATIVE AND MODIFIED NORTHERN GREAT-PLAINS RANGELAND, Journal of range management, 46(6), 1993, pp. 529-533
Research was conducted to quantify the effects of various range improv
ement treatments on diet quality and summer weight gain of steers graz
ing semiarid rangeland from 1983 through 1988. Treatments were: no tre
atment (i.e., control), contour furrowing, intertilling with a prototy
pe range improvement machine and combinations of the range improvement
machine, nitrogen fertilization, legume interseeding, or brush contro
l. Diet quality was measured in 1987 and 1988. Data were analyzed usin
g various repeated measures analysis of variance models. Various relat
ionships between the animal performance data and previously published
herbage standing crop data were examined using standard correlation pr
ocedures. There were no significant treatment (P>0.17) or year by trea
tment (P>0.82) interaction effects relative to average daily gains, to
tal gain steer(-l), and gain ha(-1) . However, all year effects were s
ignificant (P<0.05) for these variables with years accounting for abou
t 67% of the observed variation in weight pains. Percentage crude prot
ein in diet samples was greater in 1987 compared to the severe drought
year of 1988 and was greater at the beginning than at the end of each
gazing season (P<0.05). However, in vitro dry matter digestibility of
diets was greater in 1988 than 1987 primarily because digestibility o
f diets increased in 1988 from the beginning to the end of the trial.
Significant correlations between gain steer(-1) and gain ha(-1) and ea
rly season total and perennial cool-season grass standing crop estimat
es indicated same rudimentary information is available at the beginnin
g of each grazing season for predicting season-long weight gains. Beca
use average daily pains during late spring and early summer were sever
al fold greater than late season gains in all years except one, it is
hypothesized that intensive early stocking strategies may be appropria
te for stocker cattle grazing in the Northern Great Plains.