Forestry is the science of developing and managing forests including cultivating them.
Type of Forests
- Natural forests-which grow by natural means of seed dispersal.
- Semi-natural/derived/cultivated forests-which is in the process of recovering from interference by man.
- Planted/cultivated forests-which have been planted by man.
- Indigenous forests-which are native to a region or which have grown in a region from the beginning.
- Exotic forests-which have trees which have been introduced to a place from other countries.
- Other types have been discussed in the chapter of vegetation.
Factors Influencing Types and Distribution of Forests
- High temperature causes fast growth of trees while low temperature causes slow growth.
- Rain forests are found at low altitudes which are warmer while coniferous forests are found at high altitudes which are cooler.
- Dense forests are found on windward slopes of mountains because they are wetter than leeward slopes and they start at a lower level than on the leeward slopes.
- In temperate region slopes facing equator have dense forests because they are warmer while those facing the poles have coniferous forests which are adapted to low temperatures.
- There are dense forest where there is heavy precipitation while there is less forest cover consisting of stunted trees in areas with little precipitation.
- Coniferous forest have cone-shaped crowns to allow snow to slide off so as not to accumulate on the branches and cause them to break off.
- Deep soils support huge tropical trees while shallow soils support coniferous trees which have shallow and wide spread root system to be able to maximally utilise water on the top soil since the sub soil is permanently frozen.
- Poor or infertile soils have stunted trees.
- Deforestation and shifting cultivation- man has cleared forests to create room for agriculture settlement etc. which has reduced forest cover on the earth’s surface.
- Afforestation and Agroforestry-man has planted trees in areas where they never existed establishing forests there.
- Reafforestation-man has replanted forests which he has cleared with indigenous and exotic trees causing natural forests to become semi-natural/secondary or derived forests.
Importance of Forests to Kenya
- Forests are water catchment areas which supports agriculture and H.E.P. generation.
- Forests provide us with wood fuel e.g. firewood, charcoal and saw dust.
- Forests prevent soil erosion by their roots binding the soil together, reducing run off thereby reducing incidents of flooding and dam siltation.
- Forests are habitats of wild animals which are a tourist attraction which brings foreign exchange used to import goods and services and fund development projects.
- Forests are a disposal system for carbon dioxide which they use in photosynthesis and release oxygen thereby purifying air and reducing global warming.
- Forests increase soil fertility when leaves fall and rot forming humus.
- Forests regulate the climate of an area by creating a micro climate causing heavy and frequent rain by evapotranspiration and lowering temperatures.
- Forests are a source of timber for construction and furniture making.
- Forests beautify the environment by flora (plants) and fauna (animals).
- Some forest’s trees are a source of medicine.
- Presence of forests has led to the development of infrastructure as roads have been constructed to make forests accessible.
- Forests provide employment to people e.g. forest guards, forest officers, lumberjacks, carpenters and timber merchants.
Importance of Forest Products
- Forests are a source of food e.g. fruits, honey, mushrooms and bamboo tender leaves which are used for vegetables.
- Forests provide wood used for manufacture of paper, soft boards, ply wood etc.
- Animals in forests are hunted for food, skins and horns.
- Leaves of trees and forest undergrowth are used as livestock fodder.
- Forests provide wood which is used in cottage industries for making carvings and wooden utensils which are sold locally and exported.
- Forest flora and fauna are a rich reservoir for research.
Problems Facing Forestry in Kenya
- Encroachment by people by clearing them to create room for agriculture and settlement, grazing etc. which puts some plants and animal species in danger of extinction.
- Destruction especially of young trees by herbivorous wild animals such as elephants due to rapid increase in the population.
- Destruction of huge tracts of forests by fires caused by poachers, honey harvesters etc. especially during the dry season.
- Pests and diseases outbreak which can result in destruction of large tracts of land with valuable tree species e.g. there was an outbreak of aphids in 1980s which destroyed cypress.
- Overexploitation whereby the trees are harvested at a higher rate than which they are being replaced naturally and also harvesting of immature trees.
- Excision of forests e.g. by converting some parts of forests into private land, government land like Nyayo Tea Zones and public utilities like Agricultural Show Grounds which has resulted into reduction of the area under forests.
- Poor management of forests e.g. clear cutting which may lead to harvesting of immature trees in future, government officials carrying out illegal logging and government in the past having not been strict in forest conservation of forests which led to destruction of large areas of forests.
Management and Conservation of Forests
Conservation of forests is protection of forests against interference and destruction by man while forest conservation is effective planning and control of forests and forest resources.
- Creation of forest reserves to protect indigenous forests from extinction e.g. Mt. Kenya forest, Shimba Hills and Arabuko Sokoke.
- Setting of forest guard posts in the forests to protect forests against illegal logging (tree felling).
- Setting Nyayo Tea Zones to act as protective belts to prevent people from trespassing into the forests. They are also a source of employment and foreign exchange.
- Afforestation and reafforestation.
- Agroforestry (intercropping of various crops with trees) which:
- Supplies wood resources
- Provides animal fodder
- Provide food e.g. fruits e.g. mangoes and avocadoes for good health and nutrition
- Acts as wind breakers and
- Shade for crops.
- Research to determine which tree species are suitable for which area and how to combat pests and diseases outbreak.
- Carrying out public campaigns through mass media on the importance of forests.
- Use of alternative sources of energy e.g. sun, wind, biogas and water to reduce the rate of tree felling.
- Use of energy saving stoves to reduce the rate of overexploitation of wood fuel.
- Improvement on cutting practices by selective falling of trees and replanting more trees than those cut.
- Control of pests and diseases which affect trees.
Importance of Forest Management and Conservation
- Are a source of utility products e.g. firewood for fuel and food from fruits and nuts.
- For ecological reasons in that they help in the following ways:
- To preserve flora and fauna
- It’s a water catchment area
- Moderating the flow of water reducing soil erosion and floods which also prevents siltation of dams.
- For posterity i.e. so that the future generation will have forest resources available for their use.
- Industrial reasons because forest products are used as raw materials in the industries such as furniture, paper making, etc.
- Forests are important for scientific research such as on herbal medicine and genetic mapping of the species of plants and animals which haven’t been identified.
Softwood Forests in Kenya and Canada
Factors Favouring the Development of Softwood Forests
- Cool climate of Kenya highlands which enables coniferous forests to thrive e.g. Mt. Kenya and Aberdares.
- Heavy rainfall received in Kenya highlands and low evaporation rates which supports forest growth.
- Ruggedness and steepness of some parts of Kenya highlands making them unsuitable for settlement thereby leaving forests to thrive.
- High demand for timber and wood products locally and outside the country which encourages tree farming.
- Cool and cold climate which favours growth of coniferous forests.
- Very low average temperatures in the interior which favours the growth of coniferous forests.
- Ruggedness and steepness such as of British Columbia which discourages agriculture and settlement leaving forests to thrive.
- Very low population density leaving a lot of land available for forests.
- Heavy rainfall on the windward slopes of mountain ranges of British Columbia and low evaporation in the east giving sufficient moisture to sustain forests.
Mode of Exploitation
- Workers are transported daily to logging sites in Kenya while in Canada settlement is set for workers within forests.
- Power saws are used in both countries to fell trees but axes are used to a limited extent in Kenya.
- In Kenya transportation of logs is by tractors and lorries while in Canada rivers are widely used to transport logs by floating.
- In both countries logging is systematic and it is done in blocks.
Factors Favouring Exploitation of Softwoods
- Doesn’t experience winter so logging can go on throughout the year.
- Soft wood forests in Kenya are easier to exploit because trees are planted in rows unlike in Kenya where they are natural and trees grow haphazardly.
- In Kenya forests are accessible throughout the year unlike in Canada where forests in the north are inaccessible during severe winter and ruggedness.
- In Kenya logging can go on throughout the year because there is no winter.
- Availability of water from R. Nzoia for pulp and paper manufacture at Webuye.
- Ready market due to high demand for wood products locally and outside in COMESA.
- Mild winters in British Columbia which makes it possible to transport logs throughout the year.
- Availability of water from many rivers providing plenty of water for paper and pulp manufacture.
- Cheap H.E.P. for factories from many rivers in Canada.
- Cheap and efficient land and water transport system easing transport of logs to factories and to markets.
- Coastal location of major producing areas making exportation of timber to U.S.A. and Japan easy.
- High demand for forest products in the neighbouring U.S.A. and locally due to high purchasing power.
- Existence of natural coniferous forests in pure stands (one tree species covering a large area) making exploitation easy.
- Absence of undergrowth which makes exploitation easy (due to dead leaves resulting in acidic humus.
Planted soft Woods in Kenya
- Planted in clear rows.
- Clear cutting
- Mature at the same time.
In Kenya and Canada products are poles sawn timber, pulp, paper, block board, ply wood, clip board etc.
Economic Significance of Softwood Forests in both Countries
- Provides employment to people e.g. lumberjacks, tree farmers and in timber related industries.
- Has led to development of timber/wood related industries e.g. furniture, paper manufacture etc.
- A foreign exchange earner when in Canada timber is exported to U.S.A. and when products in Kenya are exported to COMESA.
- Saving some foreign exchange when the country produce wood products to cater for their needs on which they’d otherwise spend foreign exchange.
- Infrastructural development when roads are constructed to ease transportation of logs to industries and products to markets.
- Provide income to tree farmers.
Problems in Kenya and Canada
- Forest fires which destroy large tracts of land where in Canada the greatest number of fires are caused by lighting while in Kenya they are caused by illegal loggers, poachers, etc.
- Pests and diseases e.g. aphids which destroyed cypress in 1980s.
- Overexploitation leading to soil erosion as trees takes long time to mature and provide sufficient cover to the soil after planting.
- Canada’s trees take long time to mature (50-60 years due to severe winters which slow their growth. In Kenya they take 12-35 years.
- In Canada there is problem of inaccessibility of forests in the northern part in winter and due to rugged terrain while in Kenya they are planted and easily accessible.
Comparison of softwood forests in Kenya and Canada
- Soft wood forests in both countries experience the problems of pests and diseases, fires, soil erosion and overexploitation.
- Softwood forest products are similar e.g. sawn timber, wood pulp, paper, poles, etc.
- Softwood forests in both countries grow in places with heavy rainfall, cool temperatures, heavy rainfall and rugged terrain.
- Forest products earn foreign exchange in both countries.
- Tree species are similar e.g. there is pine in both countries.
- Species of trees differ e.g. in Kenya there is Kenya cedar and podo while in Canada there is Douglas fir and white pine.
- Canada’s soft woods are mainly natural while Kenya’s are mostly planted.
- Kenya’s softwood forests are found in highlands while Canada’s are found in lowlands due to cool temperatures.
- Canada’s softwood forests cover large tracts of land than Kenya’s.
- In Kenya softwood forests are propagated by afforestation while in Canada it’s by leaving some trees uncut so that they produce seeds to be dispersed naturally.
- Canada’s softwood forests take longer to mature than Kenya’s due to severe winter temperatures.
- Kenya’s softwood forests are planted in rows and easily exploitable unlike Canada’s which grow naturally and haphazardly.
ALL GEOGRAPHY NOTES FORM 1-4 WITH TOPICAL QUESTIONS & ANSWERS