Articles by Author: F O Hobson

Search results for F O Hobson

We found 9 results for you
  1. The utilization of karoo veld by livestock

    The utilization of karoo veld by livestock

    Three major utilization strategies: correct stocking rates; application of rotational grazing; and diversification of stock, for effective utilization of the veld in the Karoo areas, are discussed in terms of their importance, associated problems and possible solutions to the problems...
  2. Exploring the potential of the descending‐point method to measure utilization in karoo veld

    Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa
    The descending‐point method of vegetation survey proved effective in measuring meaningful plant cover changes during a grazing period. No significant changes in basal cover or plant height were detected. Changes in canopy spread and canopy cover could only be used...
  3. Towards a plant‐based technique to measure utilization of karoo bushes

    Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa
    The precision of various destructive techniques for estimating utilization of karoo bushes was investigated with the prerequisite that removal of 20 % of the edible material of individual species could be shown to be statistically significant. Where the total mass...
  4. An ocular technique for estimating utilization of karoo bushes

    Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa
    A subjective technique for estimating utilization of karoo bushes is evaluated and guidelines for its use are proposed. Taking the average utilization from estimates on 30–40 bushes, 20% differences in utilization could be distinguished as significant ‐ even when different...
  5. Evaluation of three objective point‐sampling techniques to measure utilization of karoo bushes

    Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa
    Three techniques to measure utilization of karoo bushes were evaluated. Precision, accuracy and consistency were measured on three species at different times and levels of utilization. The percentage‐cover technique was less sensitive and less efficient than the percentage‐edible‐strikes and percentage‐twigs‐grazed...
  6. Quantifying indices of potential competitiveness and browse productivity of single‐stemmed <em>Acacia karroo</em> trees in south‐eastern Africa

    Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa
    The prediction of indices of potential competition with grass and browse productivity of single‐stemmed Acacia karroo trees, using various trunk and canopy parameters, was evaluated on the basis of the variance accounted for by each of four operators and the...
  7. An alternative approach to veld condition assessment in the non‐grassveld regions of South Africa

    Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa
    Traditional veld condition assessment methods score veld either in terms of its ‘state of health’ or its value for a specific land‐use objective. This is problematic and we propose that ‘veld condition’ should simply be a descriptive index, devoid of...
  8. Aspects of the seed ecology of Acacia karroo in the Eastern Cape, South Africa

    Aspects of the seed ecology of Acacia karroo in the Eastern Cape, South Africa

    Item type: Journal Article • Journal: African Journal of Range & Forage Science
    Seed ecology may play a role in the widespread increase of Acacia karroo in savanna and grassland. Accordingly, fecundity, predation, mortality by fire, dispersal by livestock, and seed longevity were studied. Seed production per tree (P of pod production, pods...
  9. A test of an autonomous underwater vehicle as a monitoring tool in shallow water

    A test of an autonomous underwater vehicle as a monitoring tool in shallow water

    Item type: Journal Article • Journal: African Journal of Marine Science
    The utility of micro-autonomous underwater vehicles (AUVs) to detect hydrographic features that concentrate phytoplankton cells was evaluated during a study in a shallow tidal estuary. This study represented the first field test of Ranger™, a micro-AUV adapted for environmental applications...