Table 1 Description of the underlying geology, soil set and additional comments related to the five sites used for the first trial

A9

Gabbro of the Usushwana complex

M set: Soil deep red-orange apedal loams with weak blocky structure in the argillic subsurface horizon. Friable dry consistency. Base status low and weatherable minerals absent or very rare.

Only site measured up to rotation age, 15 years (Khoza, Planning Manager Usutu, personal communication, 2013).

B17

Lochiel Hood granite with dolerite and minor occurrences of Usushwana complex gabbro, granitised gneiss and alluvium.

Q set: Soil grey loam which may be gravelly of 30 to 50 cm over deep friable gravelly loam. Gravel is almost entirely quartz. Base status and weatherable minerals content very low.

C9

Experienced severe hail storm at age 4 years (Germishuizen 1979).

Destroyed by fire in 2007 (Khoza, Planning Manager Usutu, personal communication, 2013).

D5

Lochiel Hood granite and granitised gneiss with dolerite and minor amphibolite.

T/Q set: Soil less than 75 cm deep soil reddish or yellowish grey, loam sand to sandy loam over soft weathering acid rock. Topsoil has weak or single grain structure and loose consistence. Base status very low, although content of weatherable feldspars may be quite high.

Ridge top. Exposed and subject to wind (Germishuizen 1979).

Destroyed by hail in 2002 (Khoza, Planning Manager Usutu, personal communication, 2013).

E2

Lochiel Hood granite, but also granitised gneiss, dolerite intrusions and amphibolite.

N set: Soil yellow brown loam to clay loam merging into red clay loam to clay within 100 cm. Yellow topsoil may have humic darkened surface and has very weak or apedal structure and very friable dry consistence. Base status low and weatherable minerals absent.