Ecological thinning
Encyclopedia
Ecological Thinning is a silvicultural
technique used in forest management
that involves cutting trees to improve functions of a forest other than timber production.
Although thinning
originated as a man-made forest management
tool, aimed at increasing timber
yields, the shift from production forests to multifunctional forests brought with it the cutting of trees to manipulate an ecosystem
for various reasons, ranging from removing non-native species
from a plot to removing poplars growing on a riverside beach aimed at recreational use.
Since the 1970s, leaving the thinned trees on the forest floor has become an increasingly common policy: wood can be decomposed in a more natural fashion, playing an important role in increasing biodiversity
by providing habitat to various invertebrates, birds and small mammals. Many fungi (e.g. Calocera viscosa) and mosses are saproxylic or epixylic as well (e.g. Marchantiophyta
) – some moss species completing their entire life-cycle on a single log.
Where trees are managed under a commercial regime, competition is reduced by removing adjacent stems that exhibit less favourable timber quality potential. When left in a natural state trees will "self-thin", but this process can be unreliable in some circumstances. Examples of this can be found in the Buxus
- Ironbark
forests and woodland
s of Victoria
(Australia
) where a large proportion of trees are coppice, resultant from timber cutting in decades gone by.
where conservation
objectives are a high priority. Methods of ecological thinning being developed on silvicultural
techniques for local forest types. Ecological thinning is being developed using two principles: 1. appropriate stem reduction to reduce competition and 2. retention of trees (selection) that are more suitable for wildlife (i.e. not timber production). An example of ecological thinning research is the project in Victoria's Box-Ironbark forest
s, investigating various thinning and timber removal methods under an Adaptive Management
or AEM framework. The primary objective is to generate (over time) a number of forest habitat values (i.e. tree hollows) that are crucial for wildlife conservation
.
Silviculture
Silviculture is the practice of controlling the establishment, growth, composition, health, and quality of forests to meet diverse needs and values. The name comes from the Latin silvi- + culture...
technique used in forest management
Forest management
200px|thumb|right|[[Sustainable development|Sustainable]] forest management carried out by [[Complejo Forestal y Maderero Panguipulli|Complejo Panguipulli]] has contributed to the preservation of the forested landscape around [[Neltume]], a sawmill town in Chile...
that involves cutting trees to improve functions of a forest other than timber production.
Although thinning
Thinning
Thinning is a term used in agricultural sciences to mean the removal of some plants, or parts of plants, to make room for the growth of others.- Forestry :...
originated as a man-made forest management
Forest management
200px|thumb|right|[[Sustainable development|Sustainable]] forest management carried out by [[Complejo Forestal y Maderero Panguipulli|Complejo Panguipulli]] has contributed to the preservation of the forested landscape around [[Neltume]], a sawmill town in Chile...
tool, aimed at increasing timber
Timber
Timber may refer to:* Timber, a term common in the United Kingdom and Australia for wood materials * Timber, Oregon, an unincorporated community in the U.S...
yields, the shift from production forests to multifunctional forests brought with it the cutting of trees to manipulate an ecosystem
Ecosystem
An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving , physical components of the environment with which the organisms interact, such as air, soil, water and sunlight....
for various reasons, ranging from removing non-native species
Introduced species
An introduced species — or neozoon, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its indigenous or native distributional range, and has arrived in an ecosystem or plant community by human activity, either deliberate or accidental...
from a plot to removing poplars growing on a riverside beach aimed at recreational use.
Since the 1970s, leaving the thinned trees on the forest floor has become an increasingly common policy: wood can be decomposed in a more natural fashion, playing an important role in increasing biodiversity
Biodiversity
Biodiversity is the degree of variation of life forms within a given ecosystem, biome, or an entire planet. Biodiversity is a measure of the health of ecosystems. Biodiversity is in part a function of climate. In terrestrial habitats, tropical regions are typically rich whereas polar regions...
by providing habitat to various invertebrates, birds and small mammals. Many fungi (e.g. Calocera viscosa) and mosses are saproxylic or epixylic as well (e.g. Marchantiophyta
Marchantiophyta
The Marchantiophyta are a division of bryophyte plants commonly referred to as hepatics or liverworts. Like other bryophytes, they have a gametophyte-dominant life cycle, in which cells of the plant carry only a single set of genetic information....
) – some moss species completing their entire life-cycle on a single log.
Where trees are managed under a commercial regime, competition is reduced by removing adjacent stems that exhibit less favourable timber quality potential. When left in a natural state trees will "self-thin", but this process can be unreliable in some circumstances. Examples of this can be found in the Buxus
Buxus
Buxus is a genus of about 70 species in the family Buxaceae. Common names include box or boxwood ....
- Ironbark
Ironbark
Ironbark is a common name of a number of species in three taxonomic groups within the genus Eucalyptus that have dark, deeply furrowed bark....
forests and woodland
Woodland
Ecologically, a woodland is a low-density forest forming open habitats with plenty of sunlight and limited shade. Woodlands may support an understory of shrubs and herbaceous plants including grasses. Woodland may form a transition to shrubland under drier conditions or during early stages of...
s of Victoria
Victoria (Australia)
Victoria is the second most populous state in Australia. Geographically the smallest mainland state, Victoria is bordered by New South Wales, South Australia, and Tasmania on Boundary Islet to the north, west and south respectively....
(Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
) where a large proportion of trees are coppice, resultant from timber cutting in decades gone by.
Ecological thinning research
Research programs under way in various parts of the world (e.g. USA and Australia) are aimed at providing an alternate approach in forest managementForest management
200px|thumb|right|[[Sustainable development|Sustainable]] forest management carried out by [[Complejo Forestal y Maderero Panguipulli|Complejo Panguipulli]] has contributed to the preservation of the forested landscape around [[Neltume]], a sawmill town in Chile...
where conservation
Conservation movement
The conservation movement, also known as nature conservation, is a political, environmental and a social movement that seeks to protect natural resources including animal, fungus and plant species as well as their habitat for the future....
objectives are a high priority. Methods of ecological thinning being developed on silvicultural
Silviculture
Silviculture is the practice of controlling the establishment, growth, composition, health, and quality of forests to meet diverse needs and values. The name comes from the Latin silvi- + culture...
techniques for local forest types. Ecological thinning is being developed using two principles: 1. appropriate stem reduction to reduce competition and 2. retention of trees (selection) that are more suitable for wildlife (i.e. not timber production). An example of ecological thinning research is the project in Victoria's Box-Ironbark forest
Box-Ironbark forest
Box-Ironbark forest is a forest or woodland ecosystem that is largely limited to central Victoria in south-eastern Australia. Because its component tree species produce abundant nectar and pollen throughout the year, it is important for the conservation of many species of birds and other...
s, investigating various thinning and timber removal methods under an Adaptive Management
Adaptive management
-What is Adaptive Management ?:Adaptive management , also known as adaptive resource management , is a structured, iterative process of optimal decision making in the face of uncertainty, with an aim to reducing uncertainty over time via system monitoring...
or AEM framework. The primary objective is to generate (over time) a number of forest habitat values (i.e. tree hollows) that are crucial for wildlife conservation
Wildlife conservation
Wildlife conservation is the preservation, protection, or restoration of wildlife and their environment, especially in relation to endangered and vulnerable species. All living non-domesticated animals, even if bred, hatched or born in captivity, are considered wild animals. Wildlife represents all...
.
Sources
- Parks Victoria Box-Ironbark Parks & Reserves - follow link to thinning trial FAQ
- Ecological Thinning Conference Poster - Poster presented to ESA2004 in Adelaide, Australia
- Review of Thinning Prescriptions - Review of thinning in park management in Australia
- Cedar River Watershed Habitat Conservation Plan - Catchment project in Seattle, USA