Fire Management Tool PDF

Fire as a management tool Primary reasons to burn veld: Remove moribund material Eradicate bush encroachment Promote biodiversity (heterogeneity) Secondary reasons to burn veld: Control ticks Stimulate germination Reduce selective grazing Rotate game Security of assets Reason...

Fire as a management tool Primary reasons to burn veld: Remove moribund material Eradicate bush encroachment Promote biodiversity (heterogeneity) Secondary reasons to burn veld: Control ticks Stimulate germination Reduce selective grazing Rotate game Security of assets Reasons not to burn veld: To stimulate an out of season green bite Reason: - Reduces vigour - Reduces cover - Increases erosion Fire Regime (Summer Rainfall) Season Frequency Intensity Season Effect of season Not damaging to herbaceous layer in: Mid summer drought Mid winter Before the 1st spring rain Just after the 1st spring rain Conclusion: Season not important but physiological state of plant important Damaging to the herbaceous layer in growing season There is a decrease in: Productivity Basal cover Species richness Best time to burn in savanna: Moribund material - Just after the 1st spring rain Jan Sept Oct Dec Bush encroachment - Mid summer drought Jan Sept Oct Dec - Just before the first spring rain Biodiversity (heterogeneity) - All year but with highest frequency around 1st spring rains (= natural pattern) Jan April Sept Oct Dec When burning controlled block burns to remove moribund material or eradicate bush encroachment, we generally do not burn in mid winter. Why? To prevent exposing the soil to the elements for too long a period Frequency No set rule Depends mainly on: Rate of litter accumulation - Utilization - Rainfall Objective - Moribund (Sourveld) - Bush encroachment (Mainly sweetveld) - Biodiversity Types and intensity of fire Types: Ground fire - below surface Surface fire - herbaceous layer  head  back Crown fire - canopies  head Intensity Influenced by: Fuel load Fuel moisture Relative humidity Air temperature Wind speed Remove moribund material: Intensity < 1000 kj/s/m (cool fire) This can be achieved by: Fuel load: 1500 kg/ha Relative humidity: > 50 % Air temperature: < 20 degrees Burn time: up to 11:00; after 15:30 Control bush encroachment: Intensity > 2000 kj/s/m (hot fire) This can be achieved by: Fuel load: 3000 to 4000 kg/ha Relative humidity: < 30 % Air temperature: > 25 degrees Burn time: 11:00 to 15:30 Promote biodiversity Variable intensity: Point ignition Grazing and browsing management after a burn Sweetveld Usually burn to control encroachment and not to remove moribund material Also we know: Susceptible to overgrazing Long rests promote seed production Long rests are required for fodder build-up Therefore: Grazing must be withheld for as long as possible after a fire (1 growing season) but introduce browsers before woodies recover through coppice (coppice 100 to 150 mm) Sourveld Usually burn to get rid of moribund material (sometimes for bush encroachment) In the absence of quantitative data, the following recommendation can be made:  Grazing should commence only when grass has recovered to a height of 100 to 150 mm (usually 6 to 8 weeks) but where early grazing is essential for animal nutrition or cannot be avoided (such as with game), the following recommendations should be followed:  Do not burn annually  Stock conservatively  Apply rotational grazing if possible - short occupation (1 week) - long absence (1 month or longer)   Do not excessively use desirable grasses  Rest veld later in the growing season to regain vigour Methods of burning To remove moribund material and control bush encroachment and burn any area less than 10 000 ha  Controlled block burn A D Backfire Headfire B C  To promote biodiversity (heterogeneity) - Large areas (10 000 ha to 2 million ha)  Lightning fire approach  Patch mozaic burning Point ignition  Ecological criteria assessment Point of ignition Wind blowing - Small areas (< 10 000 ha)  Controlled block burns in chessboard fashion Small block burns carried out at different times under varying conditions http://www.koedoe.co.za/index.php/koedoe/article/viewArticl e/248 Van Wilgen, B.W., Biggs, H.C. and Potgieter, A.L.F., 1998. Fire management and research in the Kruger National Park, with suggestions on the detection of thresholds of potential concern. Koedoe, 41(1), pp.69-87. Read the following on page 72 & 73: The proposed fire management alternatives Lightning fire approach Patch Mosaic Burning Ecological Criteria Assessment Firebreaks Burning a block must not be done without adequate firebreaks An adequate firebreak is one which will provide a safe point from which to lay a line of fire and not to check the advance of a rapidly-moving front of fire. Therefore, based on this principle, the firebreak need only be as wide as is required to contain the flames during the application of the back fire during the initial stages of burning a camp. Generally, when burning grassland, a firebreak of 2-3 m is adequate. However, when burning highly flammable material such as fynbos, a firebreak of 4-6 m is necessary  Types of Firebreaks:  Clean cultivated firebreaks  Burnt firebreaks - Burn a strip with fire-fighting equipment. - Mow two strips and burn centre piece. - Botha Firebox Source: Trollope (1994)  Equipment for initiating a fire Drip Torch Source: Trollope (1989) The Fire ACT In terms of the National Veld and Forest Fire Act, a farmer will be presumed to have been negligent if a fire spreads from his land, even if it started elsewhere. A contravention of the act may result in a hefty fine or even imprisonment! To follow, some commonly asked questions about the act Questions about firebreaks 1. Does everybody have to prepare a firebreak? If a fire may start on land or may spread from land, the owner of the land must prepare a firebreak on his side of the boundaries of the land. 2. What if the owner is absent and the land is leased? The word “owner” includes the lessee or other person who is in control of the land. The lessee or person in control of the land therefore has to prepare the firebreak. 3. What should a firebreak look like? A firebreak may be burned or may be hoed or ploughed, or the vegetation may be killed chemically (for instance with Roundup) and then removed. 4. How big should a firebreak be? The act implies “big enough”. It must be wide enough and long enough to have a reasonable chance of preventing a veldfire from “jumping” the firebreak. One should also have due regard to local circumstances, like the weather, climate, terrain and vegetation. Furthermore, the firebreak must be “reasonably free” of inflammable material capable of carrying a veldfire across it. 5. Do both neighbours have to prepare firebreaks on their common boundary? Yes. Every owner is obliged to prepare and maintain a firebreak on his side of the boundary between his land and any adjoining land. 6. Does the firebreak have to be exactly on the boundary? Not necessarily. Owners of adjoining land may agree to position a firebreak away from the common boundary. 7. What about environmental conservation? The act requires the owner to ensure that a firebreak does not cause soil erosion. If there are plants in the firebreak that are protected by other laws, the Fire Act prevails over such other laws and the firebreak has to be prepared irrespective of such other laws. There is, however, the requirement that, “where possible”, protected plants be transplanted, or, where it is safe and feasible, to position the firebreak so as to avoid a protected plant. 8. Does the owner of adjoining land have to be involved in burning a firebreak? Yes. When burning a firebreak along the boundary of the land, the neighbours concerned must agree on a date in advance, but if no agreement can be reached, the owner intending to burn the firebreak must give 14 days’ written notice to the owner of the adjoining land. Both owners may burn their firebreaks on the same day, but they may not do so at all if conditions on the day are not conducive to the burning of firebreaks or if the fire danger is high. If one owner burns a firebreak and the other one not, the latter must be present or must have his agent attend and the farmer must ensure that a sufficient number of people are present on his side of the boundary to prevent any spread of fire. 9. What is meant by maintaining a firebreak? It means that the firebreak must remain effective to prevent a fire from spreading across it. When regrowth of vegetation occurs, the firebreak has to be cleared or burned again. The Act stipulates that the firebreak must be “reasonably free of inflamable material capable of carrying a veldfire across it”. 10. Who decides whether an owner should prepare a firebreak? He himself should decide. However, it is necessary to prepare a firebreak on the boundary of land where a veldfire may start or spread from. Under the Act, the Minister may determine areas where, in future, it will be compulsory to prepare firebreaks. 11. Are any exceptions possible? Yes, the Minister may exempt any owner or group of owners from the duty to prepare firebreaks for good reason. Such an exemption may be subject to special conditions. Questions about fire fighting 12. The Act requires owners to have equipment for fire fighting. What equipment? The act does not stipulate, but requires equipment reasonably required in the circumstances. One therefore has to consider one’s local conditions. What will be reasonable? Fire swatters? A bakkie sakkie? 13. Must all owners have fire-fighting equipment? No, only those owners on whose land a veldfire may start or spread from. In practice this means virtually everybody. 14. What is meant by “protective clothing”? The Act does not specify, but simply says the owner of land must have such protective clothing as may be “reasonably required in the circumstances” for his workers fighting fires. Full commercial fire-fighting gear is obviously unrealistic. 15. Does an owner have to have a certain number of workers to fight a fire? Personnel have to be available to fight the fire. The Act does not specify numbers, but requires “such trained personnel as are reasonably required in the circumstances”. 16. What do you have to do when you discover a fire that is potentially dangerous? You have to do everything possible to prevent the fire from spreading; in fact you have to do everything possible to extinguish the fire. Notify all owners of adjoining land as soon as practicable. If an owner or person in control of land does not take all reasonable steps to extinguish or contain a fire, he may be found guilty of an offence – that is apart from all the possible claims for damages. 17. What if a fire occurs when the owner is absent? When the owner is absent, he must ensure that responsible persons are present who, in the event of a fire, will fight the fire and alert the owners of adjoining land. 18. Is it permissible to enter private land in case of fire? Yes. If you believe that a fire on any land is dangerous and a threat to life, property and the environment, you (and your workers) may enter that land to fight or extinguish the fire. 19. When you are fighting a fire on land other than your own, may the owner claim damages from you? While fighting a fire you may enter any land, destroy trees, grass, crops or other vegetation, break and enter any premises, and remove any vehicle or other thing. 20. What does the Act say about lighting a fire? The Act refers to any person who “lights, uses or maintains a fire” and therefore refers to someone who is involved in a fire, even though he did not light it. It is an offence if any person, in the open air:  Leaves unattended a fire before it is extinguished;  Is involved in a fire which spreads and causes injury or damage;  Throws, puts down or drops a match or any other burning material and, by doing so, makes a fire which spreads and causes injury or damage;  Is involved in a fire in a road reserve other than in a proper fireplace; and  Smokes where smoking is prohibited. These offences are punishable with imprisonment of up to 1 year, or a fine, or both. Questions about whose fault a fire is 21. From whom does one claim damages arising from a fire? The point of departure of the Act is that the owner of the land is presumed to have been negligent if a fire started on his land or spread over his land even if it started elsewhere. A claim for damages arising from a veldfire therefore is against one’s immediate neighbour from whose land the fire spread to one’s land. 22. But was the owner concerned really negligent, and does he have to pay damages? No, he is only presumed to have been negligent bacause he did not extinguish the fire or prevent it from spreading. The farmer who is the defendant may submit evidence in civil proceedings to prove that he was not negligent and that he took all the necessary precautions and did everything possible to prevent the fire from spreading. The point is: there is a presumption that the defendant was negligent until the contrary has been proved.