The Use of Livestock GPS Trackers to Determine the Grazing Patterns of Herded and Free Ranging Cattle in the Communal Rangelands of the Eastern Cape Province, South Africa

This study was set in the Eastern Cape Province of South Africa which is predominantly rural and where livelihood sustainability is largely dependent on agricultural outputs including livestock production. Land in many of the rural, former homeland areas is held under communal land tenure which means access, utilisation and management is on a collective basis. A number of grazing strategies have been applied over the last hundred years including camp rotational grazing system. However, due to a number of factors including the absence of the communal rangeland and camp boundary fence, most villages do not have a rangeland management strategy in place. Instead, unregulated continuous grazing occurs, where animals are led to the communal rangeland in the morning and collected in the evening. According to the communal farmers they do not prefer this grazing practice as it promotes selective grazing, leading to grass species composition change, invasion of alien plants and soil erosion. Hence, there is a need to explore a rangeland management strategy that will promote optimal utilization of the communal grazing. This study was, was therefore aimed at assessing the impact of herding on livestock grazing patterns using Livestock GPS Trackers impact of herding on livestock grazing patterns using Livestock GPS Trackers within three sub-villages namely, Guquka, Gilton and Sompondo. The objectives was to compare the herbaceous species composition within areas frequently visiting by herded livestock as opposed to those that were free ranging. Results showed that the grazing patterns of both the herded and free ranging cattle in Guquka and Sompondo were focused on areas close to the homesteads, arable fields and foothills. However, cattle from three households (two herded) in Gilton, did graze areas that are up the slope. Herbaceous species composition results showed that the frequently grazed areas were dominated by Eragrostis plana, Cynodon dactylon, Themeda triandra, Sporobolus africanus, and Sporobolus fimbriatus. The types of species encountered in areas frequently grazed by herded and free ranging cattle did not differ much. These finding can be an indicator of the long term grazing pressure on areas both the herded and free-ranging animals frequently visited by livestock from the three villages

The Effects of Chemical and Mechanical Control of Woody Plants on Resprouting and Seedling Production in Communal Rangelands

In many African countries, communal rangelands are threatened by woody plant encroachment. We sought to explore potential solutions for communal ranchers that would be cost-effective. We conducted two field experiments to determine (1) the effects of various tree removal treatments (10%, 20%, 50%, 75% and 100%), and herbicide application on resprouting ability and vigour of several woody plant species; and (2) the effectiveness of Tree Poppers® (a weed wrench) as a low-cost mechanical control tool to physically uproot seedlings and saplings of woody species. In the first experiment, we examined 12 plant species from 20 plots (30 m x 30 m) each subjected to tree removal, followed by herbicide application on half of the stumps for each plot. In the second experiment, eight dominant tree species were grouped into three height classes (0-49 cm, 50-99 cm, 100-150 cm) of ten seedlings and saplings per species per height class. All the tree species in this study resprouted six months after cutting. Herbicide application significantly reduced the resprouting ability of Dichrostachys cinerea (L.) Wight & Arn, Ehretia rigida (Thunb.) Druce, Vachellia robusta (Burch.) Kyalangalilwa & Boatwright and Ziziphus mucronata Willd. Tree removal positively influenced the resprouting ability and vigour of only Euclea crispa (Thunb.) Gürke. The diameter of stumps was an important factor in determining resprouting ability, with shoot production decreasing with increasing stump diameter. We found no significant differences in the number of seedlings and saplings uprooted by Tree Poppers® among the different size classes. There were significant differences in the number of juveniles uprooted using a weed wrench with only a few individuals of Vachellia species uprooted. Woody plants are more likely to resprout and survive as juveniles than as adults after cutting. Communal ranchers may mechanically control shallow-rooted tree seedlings with a weed wrench but not deep-rooted ones, such as Vachellia species

Collection Priorities of Pasture Genetic Resources in the Paniceae Native to South Africa

There is an urgent need for the prioritization and ex situ conservation of pasture grass species. Many pasture grasses are still in the process of domestication and grasslands in the tropical, subtropical, semi-arid and arid regions of the world are therefore a major source of genetic material for future forage improvement. Within South Africa, it was found that the Paniceae contains several species with high pasture value and that many populations of these species are found in water-limited environments. Therefore, it was proposed that a strategy be developed for the South African National Forage Genebank to prioritize efforts to collect and conserve seed of grass species within the Paniceae, focussing especially on those species in genera Anthephora, Brachiaria, Digitaria, Panicum and Setaria located in areas receiving less than 600 mm of annual precipitation

Diet quality modifies germination of Dichrostachys cinerea and Acacia nilotica seeds fed to ruminants

The pods of many woody plants form an important part of the diet of livestock during the dry season due to their high nutritive value. However, the dispersal of seeds that remain intact and can potentially germinate after excretion is of particular concern when animals consume seeds of encroaching or invasive woody plants. The objectives of this study were to determine the effects of animal species in two experiments (experiment 1: goats, sheep; experiment 2: goats, cattle), diet quality (Medicago sativa hay, Digitaria eriantha hay) and seed characteristics (size, hardness) on the effectiveness of animal seed dispersal and germination of Dichrostachys cinerea and Acacia nilotica seeds. Owing to a limitation on the availability of seeds, the two experiments were done separately at different times. Each animal in both experiments received 1 000 A. nilotica seeds and 1 000 D. cinerea seeds mixed with either a low-quality diet (D. eriantha hay) or a high-quality diet (M. sativa hay). In experiment 1, we found a significant interaction effect of animal species (goats, sheep), diet (high-quality hay, low-quality hay), and seed species (A. nilotica seeds, D. cinerea seeds) on germination (P < 0.0001). There was also a higher seed recovery (P < 0.009) when animals were offered high-quality hay (47.4% ± 4.65) compared to low-quality hay (30.2% ± 3.24). In experiment 2, animal species affected seed recovery (P < 0.0325; goats 32.0% ± 6.44; cattle 50.3% ± 4.27) and germination percentage (P < 0.055; goats 14.1% ± 1.48; cattle 9.3% ± 0.94). The diet quality fed to the animals may affect dispersal and germination. However, animal species and seed characteristics also had important effects on germination of D. cinerea and A. nilotica seeds. Thus, all three of these factors play a major role in dissemination of viable seeds. © 2014 The Society for Range Management.The Rangeland Ecology & Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information

Variation in Weed Seed Fate Fed to Different Holstein Cattle Groups

Weed seeds may maintain their viability when passing through the digestive tract of cattle and can be therefore dispersed by animal movement or the application of manure. Whether different cattle types of the same species can cause differential weed seed fate is largely unknown to us particularly under non-grazed systems similar to Holstein-Friesian dairy farming. We investigated the effect on the seed survival of four weed species in the digestive tracts of four groups of Holstein cattle: lactating cows, feedlot male calves, dry cows and growing heifers. The weed species used were Cuscuta campestris, Polygonum aviculare, Rumex crispus and Sorghum halepense. Cattle excretion was sampled for recovery and viability of seeds at four 24 hourly intervals after seed intake. The highest seed recovery occurred two days after seed intake in all cattle groups. Averaged over weed species, dry and lactating cows had the lowest and highest seed recovery of 36.4% and 74.4% respectively. No significant differences were observed in seed recovery of the four weed species when their seeds were fed to dry cows. Based on a power model fitted to seed viability data, the estimated time to 50% viability loss after seed intake, over all cattle groups ranged from 65 h (R. crispus) to 76 h (P. aviculare). Recovered seeds from the dung of feedlot male calves showed the highest mortality among cattle groups. Significant correlation was found between seed viability and ruminal pH (r = 0.86; P<0.05). This study shows that management programs aiming to minimize weed infestation caused by livestock should account for the variation amongst cattle groups in seed persistence. Our findings can be used as a guideline for evaluating the potential risk of the spread of weeds via the application of cattle manure