Tobosa tiller defoliation patterns under rotational and continuous stocking

TitleTobosa tiller defoliation patterns under rotational and continuous stocking
Publication TypeJournal Article
Year of Publication1993
AuthorsSenock R.S., Anderson D.M., Murray L.W., Donart G.B.
JournalJournal of Range Management
Date Published1993
KeywordsAnimal husbandry, defoliation, forage, grasses, Grazing intensity, grazing management, pastures, range management, rotational grazing, Tillers

Stocking growing tobosa using high animal numbers for short periods followed by adequate rest may improve forage utilization and harvest efficiency. Four periods were monitored to investigate frequency and intensity of individual tiller defoliation in relation to grazing pressure under high-density, seasonal rotational and low-density, continuous stocking. From 34 to 38% of tiller height and 40 to 45% of tiller leaf material was removed per period in the rotational treatment while intensity of defoliation per grazing event remained consistent. In the continuous treatment, amount of tiller removed ranged from 11 to 88% and was not consistent over four periods. In both stocking treatments, increment of tiller and number of leaves removed per grazing event was negatively correlated (P < 0.01) with tiller height before grazing. Marked tiller utilization in the rotational treatment was always greater than that in the continuous treatment. Percentage of tillers defoliated in the rotational treatment ranged from 88% to 95%. In contrast, percentage of tillers defoliated in the continuous treatment was always less than 30% during all grazing periods. During growth, probability that a tiller would be grazed at least once in the rotational treatment was more than twice as great as in the continuous treatment. However, within the rotational treatment, probability of multiple grazing events (> 2) on an individual tiller was less than probability of a tiller being grazed just once. Probability of a tiller remaining ungrazed early in the season was less (P < 0.05) than later in the season for both treatments. High density rotational stocking promoted more efficient and uniform utilization of tobosa than low-density continuous stocking.