1. Causes

Various factors have been found to contribute to the process of bush encroachment. These include the reduction in the frequency of fires as well as overgrazing (e.g. caused by overstocking and fencing of farms). Another frequently cited theory is the state-and-transition model. This model outlines how rainfall and its variability is the key driver of vegetation growth and its composition. Further, climate change has been found to accelerate bush encroachment, as CO₂ in the air fosters bush growth.

2. Bush Control

As bush encroachment has been recognised as a major challenge for agricultural productivity as well as a diverse range of ecosystem services, the Namibian government has declared bush control a priority in its fifth National Development Plan (NDP5).

The term Bush Control refers to actions that are targeted at controlling the density and composition of bushes and shrubs in a given area that is affected by bush encroachment. Three different categories of measures can be distinguished:

• Responsive measures (bush thinning): the reduction of bush densities through targeted bush harvesting or other forms of removal.
• Maintenance measures (aftercare): repeated or continuous measures of maintaining the bush density and composition that has been established through bush thinning.
• Preventative measures (rangeland management practices): application of proven good rangeland management practices to prevent the excessive growth of woody species, e.g. through rotational grazing

Practices of combating bush encroachment, regardless of the exact methodology applied, are often referred to as "de-bushing". Although this term is widely used and also cited in various scientific works, it is disputed. "De-bushing" can easily be misunderstood as the practice of clearing and area of all bush plants, which is not the aim in most efforts to combat bush encroachment. The terms "bush control, "bush thinning" and "selective bush harvesting" are therefore considered more adequate terms.

3. Government Response

3.1. National Policy and Strategies

The Government of Namibia has recognised bush encroachment as a key challenge for the national economy and food safety. In its current National Development Plan 5, it stipulates that a total of 82.200 ha of land shall be treated against bush encroachment annually, i.e. through the thinning of the bush density by means of selective bush harvesting^[1]

The Government of Namibia, through the Support to De-bushing Project, pursues a value addition strategy, promoting the sustainable utilisation of bush biomass, which in turn is expected to finance bush harvesting operations.

3.2. Bush Control and Biomass Utilisation Project (2014-2021)

Beginning of 2014, a dedicated project to develop strategies and concepts for countering bush encroachment was launched in cooperation between the governments of Namibia and Germany, initially called Support to De-bushing Project. It is implemented jointly by the Namibian Ministry of Agriculture, Water and Forestry (MAWF) and the German development agency Deutsche Gesellschaft für Internationale Zusammenarbeit. Its first implementation phase ended in December 2017 and through bilateral negotiations the project was extended for a second phase, running between 2018 and 2021. The project was re-named to Bush Control and Biomass Utilisation Project to better reflect its strong emphasis on value chain development as trigger for sustainable bush control.

3.3. De-Bushing Advisory Service

In early 2016, the De-bushing Advisory Service Namibia was launched. It is a public service institution, mandated with the dissemination of knowledge on the topics of bush encroachment, bush control and biomass utilisation.^{[2] [3]}

The De-bushing Advisory Service provides the following services:

• Technical advise on bush control and biomass utilisation
• Implementation assistance for bush control activities
• Environmental advise on bush thinning
• Strengthening of existing agricultural outreach services
• Research facilitation on bush encroachment
• Linkage between farmers and bush control service providers
• Facilitation of finance opportunities

Services are provided upon inquiry and are public service and therefore not charged.

4. Economic Activity

Increasingly, the encroacher bush is seen as a resource for an extractive industry. Numerous farmers across the country, but increasingly also corporations from other sectors, harvest the bush with the intention process and sell it to off-takers.

4.1. Bush Based Products

The following products are currently produced from the encroacher bush biomass:

• Charcoal, mainly for export to South Africa and overseas markets (100.000 - 150.000 tonnes per annum)
• Wood chips for energy applications, currently at the Ohorongo Cement factory and at Namibia Breweries Limited (estimated 40.000 tonnes per annum)
• Wood briquettes mainly for private households, i.e. barbecuing or water heating
• Bush based animal feed production, on experimental basis on various farms, especially in response to severe fodder shortages during periods of drought
• Flooring/decking material, predominantly using Prosopis
• Wood carvings

4.2. Charcoal Production

Namibia has a well-established charcoal sector, which currently comprises approximately 600 producers, which employ a total of 5.000-6.000 workers. Currently, most producers are farmers, who venture into charcoal production as a means to combat bush encroachment on their own land. However, increasingly small enterprises also venture into charcoal making. As per national forestry regulations, charcoal can only be produced from encroaching species. In practice, it however proves difficult to ensure full compliance with these regulations, as the charcoal production is highly decentralised and the inspection capacities of the Directorate of Forestry are low.

In August 2016 the Namibia Charcoal Association (NCA) was launched. It is a non-profit entity and the official industry representation, currently representing an estimated two-thirds of all charcoal producers in the country.

4.3. Namibia Biomass Industry Group

Namibia Biomass Industry Group is a non-profit association under Section 21 of the Companies Act (Act 28 of 2004) of Namibia. The core objectives as enlisted in the Articles of Association of N-BiG are as follows:

• Develop market opportunities for biomass from bush encroachment
• Up-scale harvesting and supply capacities
• Address and resolve sector or industry bottlenecks, such as skills shortages and fundamental R&D
• Create an environment for enabling policy and regulatory framework
• Provide administrative support to N-BiG subscribers and members, especially in the incubation phase of becoming a biomass supplier

N-BiG was founded in 2016 and functions as the umbrella representative body of the emerging bush based biomass sector in the country.

4.4. De-bushing Advisory Service Namibia

The De-bushing Advisory Service Namibia is a public service institution of the Government of Namibia, mandated with the dissemination of knowledge on the topics of bush encroachment, bush control and biomass utilisation. It was initiated in response to the national crisis of accelerating bush encroachment especially on rangeland in vast areas of the country. It was founded in early 2016 and currently is part of the Namibian German bilateral Project on Support to De-bushing, implemented by Deutsche Gesellschaft für Internationale Zusammenarbeit. It was created as part of the 4-year bilateral cooperation project between the Namibian and German governments. It serves as a central knowledge and capacity development platform for the topic of bush control, facilitating sustainable large-scale bush control in Namibia. Its services therewith fall into the areas of rangeland management and natural resource management. Bush encroachment impacts Namibia on a large scale. Up to 45 million hectares of farmland in nine of the country’s 14 regions are affected. This equals about one third of Namibia's land area. Bush encroachment has negative impacts on livestock, groundwater recharge, tourism and biodiversity. It lowers the productivity and livestock capacity of pasture land by up to two thirds.

The content is sourced from: https://handwiki.org/wiki/Biology:Bush_encroachment_in_Namibia