Appendix 1: Cape Peninsula Vegetation, Climate, Weather and Fire

Appendix 1: Cape Peninsula Vegetation, Climate, Weather and Fire

Appendix 1: Cape Peninsula Vegetation, Climate, Weather and Fire Botanists now estimate that fynbos and renosterveld naturally burn every 8–12 years and every 3–5 years respectively. Too-frequent burning (≤6 years) favours grasses and disadvantages some fynbos species (notably some large protea shrubs).1 Introduced pine trees are particularly vulnerable to fire in the early years of growth. Mature plantations are less inflammable, but once alight, they fuel intense, uncontrollable fires. Some introduced trees and shrubs invade the indige- nous vegetation and regenerate quickly from fires to form dense stands. Although less inflammable than fynbos, they burn more intensely. Climate and weather influence fire season, the likelihood of ignitions spread- ing and the area burned (see Chapter 5). Winter is often cool and wet. The hot and windy summer and early autumn (November–March) are conducive to big, fast-moving fires. Rainfall and moisture distribution in space Rainfall varies locally, as a result of the complicated mountainous terrain and prevailing winds. North- and west-facing slopes are drier and the upper south- and east-facing slopes moister. The latter support most of the Peninsula’s natu- ral forests and plantations. However, prevailing southeasterly winds can quickly dry out the fynbos on east-facing slopes in summer. These variations contribute (along with vegetation type and accessibility to human ignitions) to high fire incidence on Table Mountain’s drier northern slopes, on Lion’s Head and Signal Hill (Figure A1.1). Winds In most major fires high winds were recorded – usually southeasters – for exam- ple, in 1902, 1909, 1920, 1934, 1938, 1982, 1986, 1991 and 2000. The southeaster blows from spring to late summer. Its desiccating effect primes the vegetation for fire and it fans and quickly spreads ignitions. Firefighters have to contend with the movement of the winds around the mountains and big swings in wind direction. Rainfall distribution in time The period 1921–49, but especially 1922–36, represents the longest sustained period of below average annual rainfall experienced in the period. If sustained 236 100 200 300 400 500 600 700 800 900 Commission). Rainfall for Southern Africa Source representing one std deviation aboveFigure and A1.2 below the 100-year average (590mm) (southern Peninsula); Newlands (eastern slopes,number Table Mountain). ofFigure bush A1.1 fires 1939–62: Molteno Reservoir (city bowl); Silvermine 1000 1500 2000 2500 3000 500 0 0 : S. D. Lynch, 2003, 1899 1903 1939 1907 1940 Molteno Reservoir Annual rainfall (mm) for1911 Cape Town, 1899–1999, with band Annual rainfall (mm) for three Cape Peninsula stations and the 1941 1915 1942 1919 1943 , WRC Report 1156/1/03 (Pretoria, South Africa: Water Research 1923 1944 Development of a Raster Database of Annual, Monthly and Daily 1927 1945 1931 1946 1935 1947 1939 1948 Silvermine 1943 1949 1947 1950 1951 1951 1955 1952 1959 1953 1963 Newlands 1954 1967 1955 1971 1956 1975 1957 1979 1983 1958 1987 Bush fires 1959 1991 1960 1995 1961 237 1999 1962 238 Appendix 1 drought is conducive to wildfires this should have been a period of unprece- dented fire incidence. However, this is not borne out by fire department figures, or the incidence of large fires, until 1934/1935 (Figures A1.1. and A1.2). The overall increase in annual fire incidence in vegetation (1900–93) is weakly correlated with annual rainfall, which fluctuates throughout. The first notable acceleration in fire incidence occurred during the middle-third of the long dry phase from 1921–49. There is a more plausible link between years of high fire inci- dence and periods of unusual inter-annual rainfall patterns. The sequences of dry spells of three to four consecutive months in the periods 1942–53, 1959/60, 1963, the early 1970s, 1991/92–1992/93 and 1997/98–2000 are notable. Seasonally, most big fires occurred in January and February. Appendix 2: Fire Causes Fire Brigade records categorise fires by location, including fires in bush, grass and rubbish. Fires in trees, reeds and hedges are also listed (very minor sources) and included (in my analysis) with bush and grass fires as ‘fires in vegeta- tion’. Fires in rubbish are excluded. Information on causes is extracted from fire brigade records for ‘fires in vegetation’ only. Categories of causes were altered across time and records were not kept throughout the period. The proportion of unknown or vaguely attributed causes (‘dropping a light’) is high, around 77 per cent for 1930–53, and not specified thereafter. More often than not, no witnesses came forward to report causes of ignitions in fires requiring fire brigade attendance. There are 34 categories of causes to which bush fires are attributed in Cape Town Fire Brigade reports, ranging from persistent, major causes, to one-offs like ‘servant burning feathers off goose and igniting hedge’.1 ‘Spontaneous combus- tion’ is listed as a cause – it is the second-largest attributed cause (19) in 1975. Overall, rubbish fires account for 9–13 per cent of fires in the category ‘fires in bush, grass and rubbish’. Major causes listed in fire brigade records for 1930–53 (ignoring rubbish fires) are ‘children playing with fire’ (116) and arson (77). Key minor causes were loco- motives, vagrants, fireworks (Guy Fawkes Day falls within peak burning season) and burning to clear vegetation. Only 17 per cent of fires were ascribed specific causes. Major attributed fire causes in state plantations and forests in South Africa from 1900–20 were unknown (51 per cent), entering forest/plantation by cross- ing exterior fire lines (43 per cent) and intentional firing (23 per cent). Figures are available for 1953–61, showing major causes as campers and smokers (31 per cent), unknown (24 per cent), arson (21 per cent), steam locomotives (11.8 per cent) and lightning or falling rocks (11.5 per cent). Cape Town fire brigade records for 1962–77 show major causes as children (677), locomotives (256) and controlled burns (262). National state forestry records for the same period (3802 fires) show major causes as arson (744 fires), lightning and falling rocks (429), smokers, campers and picnickers (379), honey hunters (247) and departmental (246). Cape Town Fire Brigade records attribute major causes during 1982/83– 1992/93 to vagrants (69), arson (40, with 33 in 1985/86) and controlled burns (37). Detailed state forestry records cease in 1984/85, with some categories recorded to 1987/88. Main causes for 1977/78–1987/88 were arson (526), lightning, and falling rocks (413), smokers, campers and picnickers (272) and honey hunters (212). 239 Notes Introduction 1. Cape Times, ‘Wind-Driven Fires Ravage Western Cape,’ 17 January 2000, front page; Cape Times, ‘Fire-Storm Sunday,’ Editorial, 18 January 2000, 10; C.N. de Ronde, 1999, ‘1998: A Year of Destructive Wildfires in South Africa,’ International Forest Fire News, 20, 73–8, 73; L. Aupiais and I. Glenn (eds.), 2000, The Cape of Flames: The Great Fire of January 2000 (Cape Town, South Africa: Inyati Publishing); F.J. Kruger, P. Reid, M. Mayet, W. Alberts, J.G. Goldammer, K. Tolhurst, 2000, ‘A Review of the Veld Fires in the Western Cape during 15 to 25 January 2000,’ Department of Water Affairs and Forestry Report. 2. S. Watson, 1995, Presence of the Earth: New Poems (Cape Town, South Africa: David Philip). 3. For a review, see W. Beinart, 2000, ‘African History and Environmental His- tory,’ African Affairs, 99, 269–302. See J.A. Tropp, 2006, Nature’s of Colonial Change: Environmental Relations in the Making of the Transkei (Athens, OH: Ohio University Press); T. Kepe, 2005, ‘Grasslands Ablaze: Vegetation Burn- ing by Rural People in Pondoland, South Africa,’ South African Geographical Journal, 87, 10–17. 4. D. Reitz, 1975 [1929], Commando: A Boer Journal of the Boer War (London: Faber and Faber), pp.147–9, 178; T. Pakenham, 1992, Scramble for Africa (London: Abacus), pp.576–8. 5. J.C. Scott, 1999, Seeing Like a State: How Certain Schemes to Improve the Human Condition Have Failed (New Haven, CT: Yale University Press), pp.45–6. 6. Key texts include R.H. Grove, 1995, Green Imperialism: Colonial Expan- sion, Tropical Island Edens and the Origins of Environmentalism, 1600–1860 (Cambridge: Cambridge University Press); J. Hodge, 2007, Triumph of the Expert: Agrarian Doctrines of Development and the Legacies of British Colonialism (Athens, OH: Ohio University Press); W. Beinart, K. Brown, and D. Gilfoyle, 2009, ‘Experts and Expertise in Africa Revisited,’ African Affairs, 108, 413–33; J. Hodge and B.M. Bennett (eds.), 2012, Science and Empire: Knowledge and Networks of Science in the British Empire 1800–1970 (London: Palgrave Macmillan). 7. S. Dubow, 2006, A Commonwealth of Knowledge: Science, Sensibility, and White South Africa 1820–2000 (Oxford: Oxford University Press). 8. Grove, Green Imperialism; P. Anker, 2001, Imperial Ecology: Environmental Order in the British Empire, 1895–1945 (Cambridge, MA: Harvard Univer- sity Press); W. Beinart, 1984, ‘Soil Erosion, Conservationism and Ideas about Development: A Southern African Exploration, 1900–1960,’ Journal of South- ern African Studies, 11, 52–83; J. Carruthers, 2011, ‘Trouble in the Garden: South African Botanical Politics ca.1870–1950,’ South African Journal of Botany 240 Notes 241 (henceforth SAJB), 77, 258–67; B.M. Bennett, 2011, ‘Naturalising Australian Trees in South Africa: Climate, Exotics and Experimentation,’ Journal of Southern African Studies, 27, 265–80; B.M. Bennett and F.J. Kruger, 2013, ‘Ecol- ogy, Forestry and the Debate over Exotic Trees in South Africa,’ Journal of Historical Geography, 42, 100–9; R. McLeod, 2000, ‘Introduction’ to ‘Nature and Empire: Science and the Colonial Enterprise,’ Osiris, 15, 1–13. On net- works, see D. Wade-Chambers and R. Gillespie, 2000, ‘Locality in the History of Colonial Science,’ Osiris, 15, 221–40.

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