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The purpose of this study was to determine the effects of a microcycle (4 weeks) combined rugby conditioning plyometric compared with a nonplyometric rugby conditioning program on selected physical and motor performance components and anthropometric measurements of university-level rugby players. Players (18.94 ± 0.40 years) were assigned to either a control (n = 16) or experimental group (n = 19) from the U/19 rugby teams of the North-West University (South Africa). Twenty-six direct and indirect anthropometric measurements were taken, and the players performed a battery of 5 physical and motor performance tests before and after a microcycle (4 week) combined rugby conditioning plyometric (experimental group) and a nonplyometric rugby conditioning program (control group). The dependent t-test results showed that the control group's upper-body explosive power decreased significantly, whereas the stature, skeletal mass, and femur breadth increased significantly from pre- to posttesting. The experimental group showed significant increases in wrist breadth, speed over 20 m, agility, and power and work measurements of the Wingate anaerobic test (WAnT). Despite these results, the independent t-test revealed that speed over 20 m, average power output at 20 seconds, relative work of the WAnT, and agility were the only components of the experimental group that improved significantly more than the control group. A microcycle combined rugby conditioning plyometric program therefore leads to significantly bigger changes in selected physical and motor performance components of university-level rugby players than a nonplyometric rugby conditioning program alone. Based on these findings, coaches and sport scientists should implement 3 weekly combined rugby conditioning plyometric programs in rugby players' training regimens to improve the players' speed, agility, and power.

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A survey of elephant impact at various distances from roads was conducted in June 1978 for Sclerocarya caffra (marula) tree populations in Acacia nigrescens Tropical Plains Thornveld in the Kruger National Park, Republic of South Africa. Data from scar recovery indicate that widespread scarring of S. caffra trees by elephant commenced in 1973, coinciding with a wet cli- matic phase. Elephant impact, old and fresh and irrespective of kind, decreased with distance from roads. Substantially higher impact was also recorded along S. caffra population boundaries. The most recent impact on some populations was higher than expected from the established relationship between elephant impact and tree density.

The vegetation of the Nylsvley Nature Reserve in the Transvaal Mixed Bushveld is classified hierarchically by the Braun-Blanquet Method of vegetation survey. The vegetation is seasonal grassland and deciduous savanna with four floristically distinct major groups of plant communities: (I) grasslands and broad-leaved savannas on non calcareous sandy soils on elevated sandstone and felsite areas; (2) microphyllous thorn savannas on calcareous, clayey, bottomland alluvial soils and termitaria thickets; (3) grassland and thorn savanna on calcareous self-mulching vertic soils; and (4) secondary communities on long abandoned native settlements and recently ploughed land. Seven primary communities with 12 community variations and 4 subvariations, and three secondary communities are described on the basis of 216 releves. The survey was carried out at two levels of detail, an ecosystem study area in the broad-leaved savanna being surveyed in more detail, floristically and structurally, than the rest of the Reserve.