Ecoforestry

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Ecoforestry has been defined as selection forestry or restoration forestry. The main idea of ecoforestry is to maintain or restore the forest to standards where the forest may still be harvested for products on a sustainable basis. [1] Ecoforestry is forestry that emphasizes holistic practices which strive to protect and restore ecosystems rather than maximize economic productivity. [2] Sustainability of the forest also comes with uncertainties. There are other factors that may affect the forest furthermore than that of the harvesting. There are internal conditions such as effects of soil compaction, tree damage, disease, fire, and blow down that also directly affect the ecosystem. [3] These factors have to be taken into account when determining the sustainability of a forest. If these factors are added to the harvesting and production that comes out of the forest, then the forest will become less likely to survive, and will then become less sustainable.[ citation needed ]

Contents

Since the forest is considered an ecosystem, it is dependent on all of the living and non-living factors within itself. This is a major part of why the forest needs to be sustainable before it is harvested. For example, a tree, by way of photosynthesis, converts sunlight to sugars for respiration to keep the tree alive. The remains of the converted sugars is left in roots for consumption by the organisms surrounding the tree in the habitat. This shows the productivity of an ecosystem with its inhabitants. [4] Productivity within the ecosystem cannot come to fruition unless the forest is sustainable enough to be harvested. If most individual organisms of the ecosystem vanish, the ecosystem itself is at risk. Once that happens, there is no longer any forest to harvest from. The overall productivity of a system can be found in an equation where the Net Primary Production, or NPP, is equal to the Gross Primary Production, or GPP, minus the Respiration, or R. The formula is the NPP = GPP - R. [4] The NPP is the overall efficiency of the plants in the ecosystem. Through having a constant efficiency in NPP, the ecosystem is then more sustainable. The GPP refers to the rate of energy stored by photosynthesis in plants. The R refers to the maintenance and reproduction of plants from the energy expended.[ citation needed ]

Ecoforestry has many principles within the existence of itself. It covers sustainable development and the fair harvesting of the organisms living within the forest ecosystem. There have been many proposals of principles outlined for ecoforestry. They are covered over books, articles, and environmental agencies. All of the principles relate to the idea that in ecoforestry, less should be harvested, and diversity must be managed. Through harvesting less, there is enough biomass left in the forest, so that the forest may stay healthy and still stay maintained. It will grow at a sustainable level annually, and thus it will be able to still be harvested the following year. Through management of the diversity, species may cohabitate in an ecosystem where the forest may feed off of other species in its growth and production. [1] The Principles of Ecoforestry may be found below.

Principles of ecoforestry

The principles of ecoforestry are: [4]

NumberPrinciple
1One must consider retention. It must be the first consideration in any planned removal of trees from a stand. By placing retention at the beginning of a planned removal, one makes sure that they know what must be left to ensure the protection of such things as rare species, sites of native cultural significance, riparian zones.
2Riparian zones should not be touched. It is a sensitive area, thus tree removal should not occur there. This protects the water quality. Water quality is protected by not altering the drainage pattern of the zones. No tree removal should take place in the most sensitive areas.
3The composition and structures should be upheld so that forests may fully function. This may be subject to large old trees, snags, and large fallen trees. These pieces of the ecosystem are upheld through letting them grow and die out into a timber extraction area.
4When removing trees, the lowest impact should be used. This means not compacting the soil in the forest and building small or no roads if at all possible. This takes away the disturbance that would be done to the foundation of the forest’s grounds.
5Plan in terms of the needs of the larger watershed. The watershed zone plan designates areas where tree removal is not permitted. It also designates the areas where removal is possible, and the different types of removal available.
6Avoid the ecologically questionable clear cutting. There are methods for cutting trees to maintain structure, and to allow the trees to cohabitate in a healthy ecosystem.
7Select trees as candidates for removal by considering how abundant and redundant their structures and functions are to the rest of the forest as a whole, leaving potential wildlife trees (to become snags and coarse woody debris).
8The forest should be allowed to regenerate trees through the seeds from the trees in the logged areas. This allows tree planting to be taken out of the ecoforestry principles, allowing a natural regeneration.
9Ecological succession should be kept at all times. This will protect biological diversity. This even means eliminating the process of brush control.
10No slash burning. Fire may be used as a tool in landscapes that have a history of naturally occurring fires. Although this may be true, fire should still be used with caution.
11No pesticide use. The forest needs disease, insects, and shrub/herb vegetation. They are essential parts of a fully functioning forest, even though they involve the forest’s decay in some cases. They are natural parts that allow the ecosystem to operate as a whole.
12Maintain and restore topsoil quality. This can be done through leaving sufficiently coarse and small debris on the forest grounds.
13Maintain beauty and other natural aesthetic qualities in the visual, sound, and odor landscapes. This includes not taking away the wildlife, the plants, or structural layout of the ecosystem.
14Always look at the forest as a whole. Each part of the forest contributes to its overall needs and health. That is how the forest would have survived without human interference.
15Rely more on people and markets. Use accounting and budgeting as a solution to rely less on the destruction or harvesting from the forests.
16Don’t do wrong. If it feels wrong, then it is probably wrong. Don’t allow ignorance to persevere. Recognize that the ecosystem needs tending to. If the forest is not preserved, then it cannot be harvested forever.

Analog forestry

Analog forestry is an approach to ecosystem restoration that considers the process of forest formation and the functioning of forest services to be critical in establishing a sustainable ecosystem characterised by a high biodiversity to biomass ratio. Analogue forestry uses a synthesis of traditional and scientific knowledge to optimize the productive potential of the restoration design rather than maximise the production of one crop, and maximise ecosystem services by increasing the volumetric mass of the photosynthetic component.

Analogue forestry draws design input not only from traditional models but also from the natural forest successional dynamics. When an ecosystem is designed to be analogous to the indigenous climax state, the efficiency and dynamics of the natural processes can be replicated. These quasi-natural forests are designed to mimic the structural and functional aspects of indigenous forests and are referred to as analog forests. In addition to their ecological characteristics, analog forests are also designed to provide economic benefits. However, it is not until all the ecological requirements of the location are satisfied that economic values of species are considered. Therefore, an analog forest may comprise natural and exotic species in any proportion, the contribution to structure and function being the overriding factor that determines its use.

The theoretical underpinnings began in 1978 in San Diego and Guatemala. It was first implemented in Sri Lanka around 1981 by Ranil Senanayake as an alternative to monocultures of Pinus and Eucalyptus and has spread to India, Vietnam, Philippines, Australia, Peru, Ecuador, Colombia, Brazil, Costa Rica, Dominican Republic, Honduras, Mexico, Canada, Kenya and Zimbabwe at present.

The International Analog Forestry Network (IAFN) is currently hosted in Costa Rica.

Analog forestry is a system of silviculture that seeks to design, plan and manage ecosystems dominated by woody perennials. It has been primarily employed in tropical or subtropical areas, but can be used in temperate areas too. The design seeks to mimic the architectural structure and ecological function of the preexisting climax vegetation of the area, and can be designed to provide economic, social and environmental benefits.

Analog forestry always considers the inclusion of non-crop native species to be considered in the design and thus addresses the inclusion of native biodiversity in the design. As analog forestry also requires the inclusion of long-lived species of trees in the design it has the capacity to sequester carbon for a longer time than plantation forestry. Analogue forestry has the potential to produce very high values of photosynthetic biomass as its design calls for the inclusion of all the growth forms that occupy the three-dimensional space of the mature indigenous forest. By including many species of crops in one area analog forestry helps spread the risk of market failure on a single crop.

Mixed and irregular deciduous forest in Catalonia Mixed deciduous forest Catalonia.JPG
Mixed and irregular deciduous forest in Catalonia

Close to nature forestry

Close to nature forestry is a forest management approach treating forest as an ecological system (ecosystem) performing multiple functions. It is developing in the peri-alpine coutries of Europe (such as Switzerland, France, Germany and Slovenia) for more than 70 years, based on certain sustainable forest management practices from the late 19th century. Close to nature silviculture tries to achieve the management objectives with minimum necessary human intervention aimed at accelerating the processes that nature would do by itself more slowly. It works with natural populations of trees, ongoing processes and existing structures using cognitive approach, as in the case of so called (individual or group) selection forest (German: Plenterwald) or other types of uneven-aged forests. Its theory and practice takes forest as a self regulating ecosystem and manages it as such.

It aims at overcoming the divorce between forester and ecologist. As an important consequence, it concludes that if properly applied, it would render the segregation of forest lands into "productive" and "protected" unnecessary. [5]

History

Europe

The Arbeitsgemeinschaft für Naturgemässe Waldwirtschaft (ANW) (German : Working Group for the Close to Nature Forestry) was established in Germany in 1950. In recent years this association has increased a lot its membership. The main reasons being the increase of ecological consciousness, the growing demand for forest products or services other than wood, the damages suffered by regular forest stands, the forest death fear. [5] Another term often used to describe a close to nature approach to forest management, especially in Britain and Ireland, is Continuous Cover Forestry. [6]

Because of a 1948 forest law, [5] Slovenia has many forests managed according to the principles of close to nature forestry. In 1989 ANW promoted a meeting at Robanov Kot in Slovenia, in the Julian Alps, and the Pro Silva organization was created, with representatives of 10 countries. At present the organization headquarters are in the French region of Alsace. [5]

North America

In the United States, professor Thomas J. McEvoy has published the book Positive Impact Forestry, [7] which recommends forestry practices similar to those of the "close to nature" movement. He thinks that the precursors of this type of forestry are to be found in Europe, mainly in Germany, and particularly makes mention of Heinrich Cotta, and his famous Cotta's Preface, [8] which highlighted the importance that the study and understanding of nature should have for the foresters. As a more immediate precursor he makes reference to American forester and ecologist Aldo Leopold.

The Ecoforestry Institute consists on educational, non profit and non governmental organizations operating in US and Canada. They propose a forestry based on ecological principles, very similar to those of Pro Silva. [9]

Forest management/ecosystem management

The close to nature approach intends to bridge the discrepancies, or even antagonisms between the silvicultural and ecological visions on the single reality of forest, considering the forest as an ecological system that produces wood. The sought after solution is not to segregate the territory into areas devoted to either forestry or ecology, but to integrate all functions. [7]

Objective

The management has to obtain healthy and stable forest systems that produce wood with a minimum human intervention. The products to obtain, other than wood, are fauna habitats, biodiversity, recreational, aesthetics, and water management. The human action has the object of accelerating natural processes, but not substitute them. [5]

Silvicultural models

Forest with irregular structure and mixed composition, in NE Germany. Mixed forest NE-Germany.JPG
Forest with irregular structure and mixed composition, in NE Germany.

Pro Silva recommends to use the uneven-aged forest system, in which the ages, and consequently sizes, of trees in a forest are different. It has the advantage to offer a stable structure regarding natural disasters and plagues, and is very adequate for fauna habitat and biodiversity promotion. It provides a better soil protection, since there is a permanent tree cover. [5]

McEvoy considers that in spite of being the most close to nature system, it is difficult to implement, and proposes to use the high regular forest model, in which all trees are of the same age/size, but recommends using a regeneration system with a generous cover, to avoid soil erosion, and prevent excessive light entrance, which would promote the growth of a potent understorey. [7]

The Ecoforestry Institute, similarly to Pro Silva, recommends multi-aged and multi-species forests.

Proposed thinning frequency is about ten years, and intensity low, in order to limit the ingress of excessive light, which could promote too much understory, or the growing of epicormic shoots. It has to be directed to favor the trees that show good prospect for the future. The operations have to be done in a way that will avoid soil compaction or damage to the trees that will remain standing. [10]

Native/introduced species

When foresters plant trees, they may use either native or introduced species. Whenever foresters decide to use a species that is not native, they do it because they think that there are silvicultural advantages linked to this choice, be they the wood quality, ease of management, adaptation to the climatic conditions, shorter production delay, etc. It may be that there is information available about the behavior of this species in the habitat, or the forester is ready to make a trial.

From the ecological point of view, the introducing species is considered as a threat. The introduced species risks being invasive. Invasives displace local species, resulting in a reduction of biodiversity, a condition also to be expected if great extensions are forested using introduced species.

McEvoy [7] is very clear and strict: introduced species can not be used at all when working in a close to nature forestry system. Pro Silva makes some distinctions, based on species and conditions. [5] Natural forest systems are to be preserved, but the enrichment with certain introduced species may be positive, depending on circumstances.

Pro Silva recommendations [11]

Herbivore fauna management

The herbivore fauna, be it domesticated or wild, acts on tree seedlings and small trees. In high regular forests, the regeneration periods are chosen by the forester, and therefore it is possible to establish some control over fauna action, particularly domesticated fauna, avoiding grazing during regeneration. The un-even aged forest is continuously regenerating, and therefore it is difficult to make it compatible with grazing, and does not admit a high density of wild herbivore fauna. The pressure of herbivore fauna, mainly cervids, in some European forests, has reached an intensity that is threatening the practice of close to nature forestry. [5]

Economic aspects

Forestry's economic profitability has progressively diminished in developed countries, beginning at the end of the 20th century. This has been the result of lower lumber prices and higher operating costs. Because it requires less human intervention, the close to nature forestry has lower labor costs. [5] Also, it encourages the evolution of forests toward higher ecologic and landscape value structures. This is in demand by society, and the payment for ecosystem services is being considered

Social and community aspects

Social and community aspects entail the management of the forestry block with the minimum disturbance caused from outside. This is important as nature forestry is taking place not in complete isolation from human activities and animals grazing/browsing but within the same landscape where communities are present. The people around should be well-integrated into the forest lot in order to ensure its sustainable management. In this respect the three important issues are: protect the forest from all types of fires including extinguishing any fires that may occur during forest growth,[ needs update? ] prevention of all types of illegal removal of timber, poles and the like and, prevention of animals especially browsers entering the reserve. The trio activities are heavily influenced by the people who live around the forest block being managed. It is therefore of paramount importance that the local people should be included in any program leading to the management of nature forestry initiative. The purpose of community involvement in its management is basically to ensure forest protection against activities either introduced such as illegal removal of timber, driving of animals into the forest or natural such as control of bush fires. As the community is in close proximity to the site who has the labor power and other means to prevent destructive activities and their presence is on 24/7 basis, it became all the more important to utilize their potential power for the protection of the forest lot. In this connection, they need to be fully made aware of the purpose of forest management, they be provided with education and other skills development opportunities for forest management, they be allowed to reap some benefits such as the collection of non-timber forest products. The community is also able to provide labor for forest management activities at a cheaper rate compared to the work being done by people brought from elsewhere. It is unrealistic to think about any nature forestry initiative without considering the needs, aspirations, customs of the local community.

Close to nature forestry/sustainable forestry

Sustainable forest management has evolved to include multifunctional management, like close to nature forestry does. Nevertheless there is a distinction between them since the first seeks a compromise between competing interests, while close to nature forestry uses biodiversity improvement as a tool to improve forestry itself. [12] [5]

See also

Related Research Articles

<span class="mw-page-title-main">Forest</span> Dense collection of trees covering a relatively large area

A forest is an ecosystem characterized by a dense community of trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' Food and Agriculture Organization (FAO) defines a forest as, "Land spanning more than 0.5 hectares with trees higher than 5 meters and a canopy cover of more than 10 percent, or trees able to reach these thresholds in situ. It does not include land that is predominantly under agricultural or urban use." Using this definition, Global Forest Resources Assessment 2020 found that forests covered 4.06 billion hectares, or approximately 31 percent of the world's land area in 2020.

<span class="mw-page-title-main">Forestry</span> Science and craft of managing woodlands

Forestry is the science and craft of creating, managing, planting, using, conserving and repairing forests and woodlands for associated resources for human and environmental benefits. Forestry is practiced in plantations and natural stands. The science of forestry has elements that belong to the biological, physical, social, political and managerial sciences. Forest management plays an essential role in the creation and modification of habitats and affects ecosystem services provisioning.

<span class="mw-page-title-main">Logging</span> Process of cutting, processing, and moving trees

Logging is the process of cutting, processing, and moving trees to a location for transport. It may include skidding, on-site processing, and loading of trees or logs onto trucks or skeleton cars. In forestry, the term logging is sometimes used narrowly to describe the logistics of moving wood from the stump to somewhere outside the forest, usually a sawmill or a lumber yard. In common usage, however, the term may cover a range of forestry or silviculture activities.

<span class="mw-page-title-main">Habitat conservation</span> Management practice for protecting types of environments

Habitat conservation is a management practice that seeks to conserve, protect and restore habitats and prevent species extinction, fragmentation or reduction in range. It is a priority of many groups that cannot be easily characterized in terms of any one ideology.

<span class="mw-page-title-main">Urban forestry</span> Land use management system in which trees or shrubs are cared or protected for well-being

Urban forestry is the care and management of single trees and tree populations in urban settings for the purpose of improving the urban environment. Urban forestry involves both planning and management, including the programming of care and maintenance operations of the urban forest. Urban forestry advocates the role of trees as a critical part of the urban infrastructure. Urban foresters plant and maintain trees, support appropriate tree and forest preservation, conduct research and promote the many benefits trees provide. Urban forestry is practiced by municipal and commercial arborists, municipal and utility foresters, environmental policymakers, city planners, consultants, educators, researchers and community activists.

<span class="mw-page-title-main">Old-growth forest</span> Forest that has developed over a long period of time without disturbance

An old-growth forest is a forest that has developed over a long period of time without disturbance. Due to this, old-growth forests exhibit unique ecological features. The Food and Agriculture Organization of the United Nations defines primary forests as naturally regenerated forests of native tree species where there are no clearly visible indications of human activity and the ecological processes are not significantly disturbed. One-third of the world's forests are primary forests. Old-growth features include diverse tree-related structures that provide diverse wildlife habitats that increases the biodiversity of the forested ecosystem. Virgin or first-growth forests are old-growth forests that have never been logged. The concept of diverse tree structure includes multi-layered canopies and canopy gaps, greatly varying tree heights and diameters, and diverse tree species and classes and sizes of woody debris.

<span class="mw-page-title-main">Secondary forest</span> Forest or woodland area which has re-grown after a timber harvest

A secondary forest is a forest or woodland area which has regenerated through largely natural processes after human-caused disturbances, such as timber harvest or agriculture clearing, or equivalently disruptive natural phenomena. It is distinguished from an old-growth forest, which has not recently undergone such disruption, and complex early seral forest, as well as third-growth forests that result from harvest in second growth forests. Secondary forest regrowing after timber harvest differs from forest regrowing after natural disturbances such as fire, insect infestation, or windthrow because the dead trees remain to provide nutrients, structure, and water retention after natural disturbances. Secondary forests are notably different from primary forests in their composition and biodiversity; however, they may still be helpful in providing habitat for native species, preserving watersheds, and restoring connectivity between ecosystems.

<span class="mw-page-title-main">Ecological engineering</span> Environmental engineering

Ecological engineering uses ecology and engineering to predict, design, construct or restore, and manage ecosystems that integrate "human society with its natural environment for the benefit of both".

Articles on forestry topics include:.

<span class="mw-page-title-main">Forest ecology</span> Study of interactions between the biota and environment in forests.

Forest ecology is the scientific study of the interrelated patterns, processes, flora, fauna and ecosystems in forests. The management of forests is known as forestry, silviculture, and forest management. A forest ecosystem is a natural woodland unit consisting of all plants, animals, and micro-organisms in that area functioning together with all of the non-living physical (abiotic) factors of the environment.

<span class="mw-page-title-main">Selection cutting</span> Forestry practice

Selection cutting, also known as selection system, is the silvicultural practice of harvesting trees in a way that moves a forest stand towards an uneven-aged or all-aged condition, or 'structure'. Using stocking models derived from the study of old growth forests, selection cutting, also known as 'selection system', or 'selection silviculture', manages the establishment, continued growth and final harvest of multiple age classes of trees within a stand. A closely related approach to forest management is Continuous Cover Forestry (CCF), which makes use of selection systems to achieve a permanently irregular stand structure.

Forest management is a branch of forestry concerned with overall administrative, legal, economic, and social aspects, as well as scientific and technical aspects, such as silviculture, protection, and forest regulation. This includes management for timber, aesthetics, recreation, urban values, water, wildlife, inland and nearshore fisheries, wood products, plant genetic resources, and other forest resource values. Management objectives can be for conservation, utilisation, or a mixture of the two. Techniques include timber extraction, planting and replanting of different species, building and maintenance of roads and pathways through forests, and preventing fire.

The following outline is provided as an overview of and guide to forestry:

Forest farming is the cultivation of high-value specialty crops under a forest canopy that is intentionally modified or maintained to provide shade levels and habitat that favor growth and enhance production levels. Forest farming encompasses a range of cultivated systems from introducing plants into the understory of a timber stand to modifying forest stands to enhance the marketability and sustainable production of existing plants.

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<span class="mw-page-title-main">Even-aged timber management</span>

Even-aged timber management is a group of forest management practices employed to achieve a nearly coeval cohort group of forest trees. The practice of even-aged management is often pursued to minimize costs to loggers. In some cases, the practices of even aged timber management are frequently implicated in biodiversity loss and other ecological damage. Even-aged timber management can also be beneficial to restoring natural native species succession.

Akure Forest Reserve is a protected area in southwest Nigeria, covering 66 km2 (25 sq mi). The Akure Forest Reserve, established in 1948 and spanning approximately 32 hectares. It was created with the primary aim of safeguarding the genetic diversity of the forest ecosystem. About 11.73% is estimated to be cleared for cocoa farming and other food crops. Aponmu and Owena Yoruba speaking communities owned the forest, though, there are also minor settlements surrounding the forest. They include Ipogun, Kajola/ Aponmu, Kajola, Ago Petesi, Akika Camp, Owena Town, Ibutitan/Ilaro Camp, Elemo Igbara Oke Camp and Owena Water new Dam.

Forest informatics is the combined science of forestry and informatics, with a special emphasis on collection, management, and processing of data, information and knowledge, and the incorporation of informatic concepts and theories specific to enrich forest management and forest science; it has a similar relationship to library science and information science.

<span class="mw-page-title-main">Deforestation in British Columbia</span>

Deforestation in British Columbia has resulted in a net loss of 1.06 million hectares of tree cover between the years 2000 and 2020. More traditional losses have been exacerbated by increased threats from climate change driven fires, increased human activity, and invasive species. The introduction of sustainable forestry efforts such as the Zero Net Deforestation Act seeks to reduce the rate of forest cover loss. In British Columbia, forests cover over 55 million hectares, which is 57.9% of British Columbia's 95 million hectares of land. The forests are mainly composed of coniferous trees, such as pines, spruces and firs.

<span class="mw-page-title-main">Continuous cover forestry</span> Approach to sustainable forest management

Continuous cover forestry is an approach to the sustainable management of forests whereby forest stands are maintained in a permanently irregular structure, which is created and sustained through the selection and harvesting of individual trees. The term "continuous cover forestry" does not equate exactly to any one particular silvicultural system, but is typified by selection systems. For example, coppice with standards and Reiniger's target diameter harvesting are also continuous cover forestry. Different existing forest stands may require different silvicultural interventions to achieve a continuously productive irregular structure. Crucially, clearcutting and other rotational forest management systems are avoided.

References

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  2. Hammond H. (Fall 2003). Ecosystem-based management is high-yield forestry [ permanent dead link ]. Ecoforestry, 18(3), 6–8.
  3. Copland M. (Spring 2003). Archived 2007-06-28 at the Wayback Machine . Ecoforestry, 18(1), 3–10.
  4. 1 2 3 Dregson, A. R., & Taylor, D. M. (1997). Ecoforestry. Gabriola Island, BC : New Society Publishers.
  5. 1 2 3 4 5 6 7 8 9 10 Turckheim, Brice de, et Bruciamacchie, Max (2005). La Futaie irreguilière. Théorie et pratique de la sylviculture irreguilière, continue et proche de la nature (in French). Éditions Édusud. ISBN   978-2744905537.{{cite book}}: CS1 maint: multiple names: authors list (link)
  6. Helliwell, R.; E. R. Wilson (2012). "Continuous cover forestry in Britain: challenges and opportunities". Quarterly Journal of Forestry. 106 (3): 214–224.
  7. 1 2 3 4 Thomas J. McEvoy (2004). Positive Impact Forestry. Island Press. ISBN   9781559637893.
  8. The Forest History Society. "Cotta's Preface" (PDF). Archived from the original (PDF) on 2016-03-03. Retrieved 2011-02-20.
  9. "Pro Silva » Integrated forest management for resilience and sustainability across 25 countries". Pro Silva. 2017-08-03. Retrieved 2018-02-16.
  10. The damage to the standing trees may be reduced if the works are done during the period of low biological activity, fall and winter.
  11. "The question of non-indigenous forestspecies". ProSilva. Retrieved October 12, 2012.
  12. Malawi Principles Archived 23 December 2007 at the Wayback Machine