Reforestation in South Africa

This Evertreen project restores indigenous forest in the Uilkraal Valley of the Overberg, on the southern tip of the Western Cape. Planting takes place at two neighbouring sites, Platbos Forest and Bodhi Khaya Forest, both inside the Walker Bay Protected Environment. The two sites sit either side of a single valley, and the current focus of planting is the stretch of land that connects them.

These are not new plantations on empty ground. They are relic forests, ancient fragments of a forest system that once covered far more of the Cape lowlands and has since been reduced to isolated pockets. The work reconnects those pockets. Trees are planted on land that was previously cleared for agriculture or overrun by invasive alien vegetation, rebuilding the missing forest between one ancient remnant and the next.

Project snapshot

• Country: South Africa
• Province: Western Cape
• Region: Uilkraal Valley, Overstrand, Overberg
• Planting sites: Platbos Forest and Bodhi Khaya Forest
• Protection status: Walker Bay Protected Environment; Platbos is a declared Private Nature Reserve
• Habitat restored: Indigenous Afromontane and Platbos type forest
• Species planted: Locally indigenous mixed native species; no monocultures
• Land condition addressed: Previously disturbed land cleared of invasive alien vegetation
• Current planting focus: Blomerus, the corridor linking Platbos to Bodhi Khaya
• Harvesting: None; trees are planted for permanent protection

The two planting sites

Platbos Forest
Platbos is the southernmost indigenous forest on the African continent, and something of a botanical mystery. Unlike other Cape relic forests it grows in deep, sandy, alkaline soil on dry, gently undulating, north-facing ground. Some of its trees are estimated to be over a thousand years old, with gnarled and twisted trunks draped in old man’s beard and mottled with lichens. Platbos is a declared Private Nature Reserve, and planting takes place around the margins of the forest to shield the ancient core from wind, fire and encroaching invasive plants.

Bodhi Khaya Forest
A short distance away, Bodhi Khaya sits at the foot of the Witkransberg and forms a mosaic of indigenous forest relics running through a valley with an intact surrounding ecosystem. The site bridges Afromontane type forest higher up to Platbos type forest lower down. Bodhi Khaya has recently taken on a large area of land in need of rehabilitation, known as Blomerus, and this is where the majority of new trees are now being planted. Blomerus is the ground that closes the gap between the two forests.

How the trees are planted

The project works to a strict set of rules that shape every planting decision. Trees are always locally indigenous and diverse, never single species plantations. They go only on degraded land that genuinely needs intervention, never into an intact ecosystem, and never where pristine indigenous vegetation already stands. Every site is chosen to fit the surrounding natural context.

Each site is independently managed by conservation and rehabilitation professionals with detailed knowledge of local conditions. Sites are kept under active management for fire and erosion protection and for the continued removal of invasive alien vegetation, which is the single largest threat to what remains of these forests.

Environmental benefits

Clearing dense invasive alien vegetation and replacing it with indigenous forest changes how the whole valley functions. Alien stands such as black wattle and Port Jackson consume disproportionate volumes of groundwater and burn far more fiercely than native forest, so their removal improves water availability and lowers fire intensity across the landscape.

Replanted indigenous forest stabilises soil on slopes and along watercourses, reducing erosion and protecting the streams that run through both properties. As the canopy closes and the forest matures it also draws carbon from the atmosphere and holds it in wood and soil, with the important difference that these trees are never harvested and the land is held under formal protection.

Biodiversity

The Cape Floral Kingdom is one of the richest and most compressed concentrations of plant life anywhere on earth, and these forest relics carry species found in very few other places. Platbos alone supports thirteen major tree species, and the forest floor and canopy sustain an entire community of mosses, lichens, epiphytic ferns, birds, bees and mammals including bushbuck and honey badger.

Because the two sites are being joined rather than restored in isolation, the ecological gain is larger than the sum of the trees planted. A continuous corridor lets seed, birds and animals move between remnants that have been cut off from one another, which is what allows a fragmented forest system to start functioning as one again.

Protection and long-term management

Every planting site sits within property that is already protected and managed for conservation. Felling of indigenous trees does not take place, hunting is not permitted, and the natural movement of wildlife is not restricted. The trees planted here are intended to stand permanently.

Fire is the defining risk in this landscape, and it is managed rather than hoped away. The core of Platbos Forest is encircled by a firebreak between nine and twelve metres wide, with secondary breaks around newer planting areas. During a recent three day fire that reached these breaks, the indigenous forest came through unharmed while neighbouring stands of invasive alien trees caught and spread the flames, a direct demonstration of why replacing aliens with native forest makes the whole valley more resilient.

Photos taken at Platbos Forest by Matthew Fainman, Simon Tamblyn and Caroline Voget on iNaturalist, licensed CC BY 4.0.