PRESCRIBED BURNING AS A CONSERVATION MANAGEMENT PRACTICE - A CASE-HISTORY FROM THE CEDERBERG MOUNTAINS, CAPE PROVINCE, SOUTH-AFRICA

A fire history was derived for the Cederberg State Forest (Cape Province, South Africa) for the period 1956-1986. Fire frequency was determined by analysing the distribution of fire-free intervals observed at grid intersections superimposed on the mapped fires. The overall frequency was estimated at 11-15 years. Topography had little effect on frequency. The natural fire season was defined as November-February, and to a lesser extent March and April. Fifty-eight wildfires burnt 78000 ha in the period of observation. The effects of a policy of prescribed burning (introduced in 1973) on the extent and frequency of wildfires are not yet evident. The policy of prescribed burning in late summer and early autumn is vindicated on the basis of positive vegetation response to fires in these months. Concern is expressed at the ecological effects of prescribed burns not being carried out in the natural fire season, which may result in the local extinction of some plant species.