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The treatment of the soil and ground vegetation to prepare the soil surface as a favorable seedbed for either naturally or artificially regeneration. Organic Vs bare mineral soil seedbed Promote decomposition of surface organic matter Improving the soil structure for regeneration
Site Preparation The treatment of the soil and ground vegetation to prepare the soil surface as a favorable seedbed for either naturally or artificially regeneration Seed disseminating Site Preparation Site preparation includes: Controlling undesirable vegetation; Improving soil structure, drainage and fertility; Reducing logging slash Purposes of Site Preparation Reduce/eliminate competing vegetation Remove competing vegetation from the site Purposes of Site Preparation Reducing logging slash to regeneration Slash can impede regeneration both physically and biologically (insects, mammals, pathogens) Purposes of Site Preparation Improve character of seedbed •Organic Vs bare mineral soil seedbed •Promote decomposition of surface organic matter •Improving the soil structure for regeneration Methods of Site Preparation Mechanical Chemical Burning Mechanical treatments Physical manipulation of site Usually with large machinery Preparing the site by hand is possible and economical only for relatively small-scale projects, where the labour of clearing the competing vegetation and working the soil is not too time-consuming Mechanical treatments Mechanical site preparation with heavy equipment can be divided into three categories: breaking or crushing vegetation in place moving vegetation from the planting site manipulating soil structure or microtopography of the site Breaking Vegetation (Chopping) A significant advantage of rolling choppers is that they not displace the topsoil and they have a minimal effect on soil runoff. The most frequently-used tool used to crush existing vegetation in place is the rolling drum chopper Moving Vegetation from the Planting Site (Shearing) A more intensive treatment is the use of a shearing blade: a horizontal knife blade mounted on a large crawler tractor which shears vegetation at the ground line. Shearing can cause topsoil and seedbed displacement 10 Manipulating the Soil Disking to break up or till the soil surface, improving soil aeration and moisture movement, and helping young trees to root Disking also incorporates organic surface layers into the underlying mineral soils and prepares the surface for bedding where appropriate 11 Manipulating the Soil Bedding Bedding against the slope is essential to minimize soil erosion on upland sites 12 Manipulating the Soil Ripping Ripping encourages more deep root development than any other of the other soil treatment methods 13 Chemical treatments Use of chemicals (Herbicide) to manipulate the site in preparation for regeneration 14 Chemical treatments Chemical site preparation can be an effective method to temporarily control competing vegetation for plant growth Chemical methods may involve simple equipment, can be less expensive, and provide longer control than mechanical site preparation Chemical effectiveness depends on the appropriate herbicide selection, the timing of application and application rate 15 Chemical treatments 16 Chemical treatments Strip application Spot application 17 Prescribed burning Prescribed burning, or controlled ground fires, can be an effective and inexpensive means of removing or reducing vegetation, and preparing a suitable seedbed in advance of planting or seeding 18 Prescribed burning Effective and safe use of prescribed fire requires: Proper design of the fire breaks; Personal protective equipment; Careful evaluation of weather conditions on the day of the burn, and training 19 Prescribed burning - Advantages Relatively cost effective for large areas Reduces slash, debris, litter, fuels and competing vegetation Improve soil nutrient levels Destroys pests/diseases Induces sprouting Melia azedarach ‘ seeds need to be treated by using fire before disseminating 20 Prescribed Burning - Limitations Must adhere to the burn permit laws Damage to residual trees (depending on intensity and speed) – heated above 55C Loss of nutrients (e.g N) to atmosphere and erosion Air quality, visibility and smoke Alteration of soil properties – degradation Removal of organic material .. .Site Preparation Site preparation includes: Controlling undesirable vegetation; Improving soil structure, drainage and fertility; Reducing logging slash Purposes of Site Preparation. .. the site Purposes of Site Preparation Reducing logging slash to regeneration Slash can impede regeneration both physically and biologically (insects, mammals, pathogens) Purposes of Site Preparation. .. regeneration Methods of Site Preparation Mechanical Chemical Burning Mechanical treatments Physical manipulation of site Usually with large machinery Preparing the site by hand is possible