NEWS
Figure 3 : Rangelands are what Bond calls ‘ open ecosystems ’, variegated mixes of trees and grasslands existing together in savannahs and parklands .
diation too compared to darker forests , and so may
act to cool the earth . Yet carbon forestry schemes focus on the above-ground biomass , and tree biomass is much more visible and measurable than the poorly understood belowground carbon dynamics among root networks and in the soil . In other words , these are not degraded lands in need of restoration to a ‘ natural ’ forest .
Forest obsessions
This obsession with closed forests has a long history , seeing grasslands as ‘ degraded ’ forests , and forests as the desirable protector of environments . Many of the current well-meaning attempts to advocate reforestation replicate colonial discourses , where foresters from northern climes influenced nascent forest departments across the world .
For example , the idea of the
taux de boisement normal – the percentage of forest cover required by a ‘ civilised ’ nation – took hold in the French colonies from the 1800s , and since then tree planting has become part of what Diana Davis describes as
a civilising mission to offset ‘ desiccation ’ and the assumed ravages of desert advance . Equally , the negative description of rangelands as ‘ wastelands ’ in India has framed attempts at environmental rehabilitation from the colonial era to today .
REDD + and through investment projects available through growing voluntary carbon markets , seen as central to meeting ‘ net-zero ’ commitments globally .
The problems with tree planting in rangelands
So what are the problems with tree planting , especially in pastoral , rangeland areas ? Here are seven points ( see also this
excellent article by Forrest Fleischman and colleagues ).
• Most tree planting projects focus on exotic , fast-growing trees . These are assumed to produce the most carbon the quickest . But fast-growing trees planted in rangelands can quickly become a problem . Ask any pastoralist in East Africa about the issues they have with the invasive
Prosopis juliflora , which was originally introduced by aid programmes to provide fuelwood . Exotic tree planting also eliminates existing grassland ecosystem biodiversity , which has emerged over millennia through the interactions of vegetation and herbivores .
• Rushed planting of trees in unsuitable environments can lead to large losses of planted trees . The incentives to earn a quick buck on carbon credits can result in huge damage . Areas are cleared , trees are planted and then they die , with no benefits to anyone . In the odd calculations of carbon credits , this may have resulted in ‘ avoided deforestation ’, but the consequence is often the laying waste of environments .
• Tree planting in grasslands , aiming for a managed , stable forested area , runs counter the natural ecosystem dynamics of such areas . In
tropical grassy biomes , the number of trees and grasslands fluctuate , with patches of each increasing and decreasing because of rainfall , fire and other factors . Imposing a regularised regime of management on such a setting , assuming baselines and calculating carbon gains makes no sense .
• Tree planting schemes where people and animals are excluded can result in the massive build-up of flammable herbaceous material . Without regulated ‘ cold burn ’ fires , the consequences of forest fires can be devastating , as seen around the world in recent months . This can result in huge losses of carbon – exactly the opposite of the plan .
• Water cycles may be disrupted by tree planting schemes , as fastgrowing trees need a lot of water to grow . By contrast , grasslands have high levels of infiltration and are important in maintaining hydrological systems . Carbon schemes however do not put a price on water , so trees win out .
• The landscape value of tree plantations – serried rows of exotic trees – may be lower than that of long-established grassland systems , where cultures of livestock keeping and wildlife use have created a lived-in landscape . Rangelands may be anthropogenically created , but they are not necessarily degraded and in need of rehabilitation .
Enhancing dynamic ecologies : putting people first
Trees are natural elements of grassland landscapes and of course , have many benefits for people and environments , providing shade , fruits , browse , leaf litter and so on . In some cases , new planting may be desirable , but more often encouraging regrowth of existing trees as part of variegated landscapes makes
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