South Africa: Wildfires in Industrial Plantations (IFFN No. 11 – July 1994)
Wildfires in Industrial Plantations
(IFFN No. 11 – July 1994, p. 6-8)
Even-aged pine and eucalypt plantations have been established in South Africa since the late 1800’s to supplement the dwindling indigenous timber resources. By 1991 the area covered by these plantations reached a total area of more than 1.5 million ha, by far the biggest man-made forest on the African continent.
Most of the natural vegetation of the country where the plantations were established have a natural fire history and need fire regularly to survive (e.g. fynbos, montane grassland and savanna), and the species introduced for commercial purposes also originate from habitats where fire plays a significant role in these ecosystems. It is no wonder that the almost total exclusion of fires from these managed plantations gives rise to regular wildfire situations as fuel accumulates to alarming proportions, particularly during adverse weather conditions. The history of wildfires during the 1979-1989 period reflects this regular occurrence, although there were surprisingly fewer larger fires experienced during this period (Tab.1 and 2). However, it must be noted that these statistics exclude State-owned plantations, thus representing only ca. 57% of the total planted area.
The year 1989 was disastrous for the State-owned plantations, when during the course of a few weeks, first 2,500 ha were lost at Entabeni in the Northern Transvaal, and then 5,400 ha at Nyalazi and Dukuduku plantations in Zululand.
During 1992 a serious drought affected most of the Transvaal and Natal forest regions, when many large areas of plantations died as a result of moisture stress, adding a lot of fuel to the already tender-dry forest floor material in plantations. Although there were far more periods of high fire danger experienced in 1992 than in 1991, losses from wildfires were surprisingly lower than the previous year: Although 792 fires were recorded and attacked from the air, only a total area of 9,333 ha was lost during this season (Meikle et al., 1992).
Tab.1. Summary of plantation areas affected by wildfires during the period 1.4.1979-31.3.1985
(Le Roux 1988).
Geographical Area
Total area afforested (ha)
Total area burnt (ha)
Percentage of total area burnt (%)
Total financial losses (Rand)
Eastern Transvaal Highveld
39,644
5,496
13.86
973,818
Eastern Transvaal Lowveld
185,277
2,290
1.23
476,253
Southern Transvaal Highveld
132,317
4,411
3.33
1,726,453
Sabie Area
83,033
5,544
6.68
30,420
Northern Transvaal
38,941
541
1.39
44,370
Natal Midlands
213,740
14,420
6.75
8,562,028
Natal Interior
42,028
7,866
18.72
222,798
Zululand
16,259
217
1.33
35,985
Southern Cape
2,000
4
0.20
—
TOTAL
753,239
40,789
5.41
12,074,866
Tab.2. Summary of plantation areas affected by wildfires during the period 1.4.1985-31.3.1989
(Kromhout 1990)
Geographical Area
Total area afforested(ha)
Total area burnt (ha)
Percentage of total area burnt (%)
Total financial losses (Rand)
Eastern Transvaal Highveld
38,593
3,055
7.92
4,024,660
Eastern Transvaal Lowveld
225,079
1,825
0.81
271,519
Southern Transvaal Highveld
212,092
2,804
1.32
1,535,180
Sabie Area
61,747
377
0.55
59,991
Northern Transvaal
45,868
236
0.51
94,451
Natal Midlands
177,705
2,605
1.47
1,590,317
Natal Interior
49,430
438
0.89
271,161
Zululand
46,240
873
1.89
358,990
Southern Cape
1,000
1
0.10
—
TOTAL
857,754
12,214
1.42
8,206,269
Although some time was spent on ad-hoc fire impact studies during the proceeding 2-3 years, fire research studies in plantations reached an all time low level, with only the writer involved in some ad-hoc research experiments. Nevertheless, prescribed burning was successfully introduced in Pinus patula stands in Kangwane plantations near Swaziland, while wildfire damage assessment resulted in significant savings of timber volumes.
References:
De Ronde, C., J.G.Goldammer, D.D.Wade and R.V.Soares 1990. Prescribed fires in industrial pine plantations. In: Fire in the tropical biota (J.G.Goldammer, ed.), 216-272. Ecological Studies Vol.84, Springer-Verlag, Berlin-Heidelberg-New York, 489 p.
Kromhout, C. 1990. Analysis of fires in privately-owned plantations in the Republic of South Africa. South Africa Forestry Journal 146, 74-87.
Le Roux, P.J. 1988. Analysis of fires in privately-owned plantations in the Republic of South Africa. South Africa Forestry Journal 146, 55-66.
Meikle, S. 1992. 1992 fire season analysis. Inferno Magazine Jan./Feb.1993, 6-7, 17.
From: Neels De Ronde
Address:
Division of Forest Science
and Technology
Private Bag X11227
SA – Nelspruit 1200
Top
Country Notes
