Tall, stripy and mighty: introducing the African zebrawood

Mount Cameroon provides an impressive setting for meeting a remarkable tree. The highest mountain in Central Africa, it also holds the title of being the region’s most active volcano. Below its bare and occasionally smouldering peak at 4,095 metres, life takes hold slowly, in the form of spiky tufts of grass protruding between sharp and slippery rocks.

Descend further, and the first few trees are soon joined by dense and humid forests which stretch all the way down to Cameroon’s west coast. Here, forest elephants follow ancient trails, drill monkeys creep silently through the undergrowth and fleeting glimpses of sunbirds provide welcome flashes of colour in a dark and consuming forest.

A tree haven

The mountain is also an excellent place to become acquainted with some of Cameroon’s rarest and most spectacular wildlife: its trees. 15 of the country’s 25 Critically Endangered trees are found on Mount Cameroon and many of these are found nowhere else in the world.

Over the last few thousand years, the ancestors of these trees must surely have been central to an epic story of survival played out amidst changes in climate, volcanic eruptions, and rising human population all around the slopes of Mount Cameroon.

Amongst these great survivors, there is one particularly remarkable tree: the African zebrawood, Microberlinia bisulcata.

The price of beauty

Reaching heights of up to 40 metres, mature zebrawoods have jostled their way to the very top of a crowded canopy. Here, their minute leaves somehow absorb enough sunlight to generate much of the energy needed to support its massive bulk below. Its trunk is covered in rough patches of green, pink and grey bark which itself conceals the cream and black striped timber that gives the species its name.

African zebrawood. Credit David Gill/FFI.

An African zebrawood extends up out of the canopy. Credit David Gill/FFI.

But holding such beauty has come at a price for the zebrawood. Extensive logging has reduced the species to one population in Korup National park and a second by Mount Cameroon. The zebrawood is also threatened by an onslaught of economic development which is gradually swallowing up the mountain’s surrounding forests, with a tide of palm, rubber and banana plantations rising steadily up its slopes.

Just in time, and after pressure from WWF, Mount Cameroon was declared a National Park in 2010. Building on this impetus, the Global Trees Campaign joined forces with a local NGO, the Environment and Rural Development Foundation (ERuDeF), to support and train the National Park’s new staff to locate, protect and restore the mountain’s threatened trees.

Last year, I was fortunate enough to visit the project to evaluate the progress made and see the zebrawood which we hoped to use as a ‘pin-up’ for wider tree conservation in the park.

 

All gone?

Yet upon my arrival in Cameroon, I was far from certain that I would ever lay eyes on a zebrawood tree. Reports from the first field trips made by the team had confirmed high levels of forest loss and their surveys had failed to identify any zebrawoods at all.

Just as I was beginning to fear the worst, a warm welcome from the ERuDeF team was followed by some very good news: Louis Nkembi and Asa’a Lemawah, who coordinate the Mount Cameroon project, proudly told me that they had found a number of mature zebrawood trees in a forestry reserve on the far side of the park and if I liked I could come and see them for myself.

Little rays of hope

Meeting a remarkable tree is all the more special when you are in good company. Asa’a, Mr Mbeng from the National Park and Elias Ndive, an expert in Central African botany from Limbe Botanic Gardens, introduced me to each and every plant we passed, and took great pleasure at mocking my miserable attempts to keep pace in this hot and humid forest.

As the day wore on, and the banter died down, the moment I had waited for finally arrived when we came face-to-bark with one of Africa’s rarest species right on the side of the forest trail.

With my neck fully reclined, I took in as much of this magnificent tree as I could, from the miniscule leaves located high within the canopy down to its large buttress roots. Then, after looking around the forest floor, one last surprise was in store: a cluster of tiny zebrawood seedlings, pencil thin and barely 20 cm tall.

As these seedlings have little chance of growing under the shade of their parent tree, Asa’a carefully gathered a small proportion of them to be taken back and cared for in the project’s nursery with a view to replanting them in the park in the future.

Zebrawood nursery. Credit: David Gill/FFI.

Zebrawood nursery. Credit: Asa’a Lemawah/ERuDeF.

It can be a sobering experience to meet a remarkable tree. In appearance, zebrawoods are arguably the mightiest species in this globally unique forest. Yet they are also deceptively vulnerable and will need help if they are to play their part in the next chapter of Mount Cameroon’s epic story.

Driving through the sea of palm oil plantations back to the nursery with a collection of young zebrawood trees in the boot, I wondered what future they might have in this landscape. How nice it would be to come back in 30 years and meet one of these seedlings in the wild as a fully grown tree.

Want to keep reading? Then why not take a look at earlier instalments in this blog series. In part one (“More than just a tree hugger“) David Gill plants the seed, while in part two (“Bewitching baobabs“) IUCN’s Richard Jenkins shares his fascination with Madagascar’s iconic baobabs.