The wood for the trees
‘Data?’
‘Ready.’
‘Tree J, DBH, 52.’
‘52. Got it.’
‘Data?’
‘Ready.’
‘Tree K, canopy, east–west, 137.’
‘137. Got it.’
Enveloped in the soothing green of the Puerto Rican rainforest, I listen as the voices ring out from the gloom – my team mates busily gathering, communicating and recording information about the trees that surround us. We’re methodically making our way around a one-acre (4,047-square-metre) plot, measuring a collection of variables for each tree: height, diameter at breast height (hence the DBH above), spread of the canopy and so forth.
The terrain is steep and – following a few nice, heavy tropical downpours – satisfyingly muddy, but thankfully, the rainforest is quite spectacularly benign. Having spent several years conducting research in the rainforests of north Queensland, I had been steeling myself for the inevitable experience of being bitten by mosquitoes, stung by wasps, bled dry by leeches, and punctured and/or lacerated by the local trees, shrubs and vines. But apart from some appropriately named razor grass and a tree fern that’s armed with needle-sharp spines, there seems to be very little here that’s out to do me damage.
Interspersed among the various indigenous species are rows of considerably more valuable trees: young mahoganies, their straight trunks reaching up into the thick canopy. It’s these trees that have brought me and my team of fellow volunteers here to Patillas, Puerto Rico – they form the heart of a unique project aimed at finding new ways to conserve tropical rainforest.
VALUE ADDED
One of the classic strategies proposed for the preservation of rainforest is to make it more profitable to keep than to cut down. Much of the world’s remaining tropical rainforest
is found in developing nations, where preserving forest for its own sake is a luxury that most people can’t afford.
A variety of ways of achieving this goal have been suggested and attempted, from ecotourism ventures to the collection of forest products such as fruits and nuts. But each has struggled to provide enough of an income for the people who live in and around the forest.
The approach here is to grow high-value timber, primarily mahogany, within the forest itself. ‘The idea,’ explains Sally Silverstone, the project’s principal investigator at the time of my visit, ‘is to demonstrate alternative uses for the forest and find ways that we can make money off rainforest property while, as far as possible, leaving the biodiversity intact.’
The project is being carried out in the 409-hectare Las Casas de la Selva forest, a privately owned block of old secondary tabanuco rainforest about an hour’s drive from the island’s capital, San Juan. Keeping this forest intact is about more than just preserving the biodiversity. In this part of Puerto Rico, there is still significant clearing of land for agriculture and livestock grazing, and because the terrain is very steep – generally 30–45 degrees in slope – this results in severe erosion.
‘The property was bought during the early 1980s with the help of the Puerto Rican Department of Natural Resources, which was very keen for us to set up this demonstration project and to do it here at Patillas,’ Silverstone continues. ‘We’re on the southern border of the Carité National Forest. And because they knew that we wanted to keep the forest intact, they saw us as a buffer to the national forest.
‘We purchased several small pieces of property and put them together – mostly land that had been under cultivation during the 1920s and ’30s but was abandoned during the 1940s as people moved to the cities.’ The initial timber planting, which began in 1983 and continued until the early 1990s, involved about 40,000 mahogany, blue mahoe and other valuable native hardwood trees, spread out over an area of around 87 hectares at an elevation of about 500–600 metres.
The trees were then simply left alone to grow, before the researchers returned in 1997. ‘We wanted to come back and see what had happened,’ Silverstone says.
Silverstone and her team then embarked on an intensive research programme, evaluating everything from the growth and success of the trees to the effect that the planting has had on the local biodiversity. ‘What we want to do is prove the whole cycle – do the planting, the harvesting, the replanting – and really show that we can get it onto a continuous, sustainable cycle of harvesting, replanting, harvesting, replanting, so that it yields so much in every year but is done in a gentle and sustainable way without causing too much destruction,’ she explains.
‘Obviously, one of the key things here is that your crop has to be fairly valuable, because the work is going to be labour-intensive and it’s a long wait,’ Silverstone continues. ‘So you have to have something that you know is going to have a good selling price.’
Although very valuable, mahogany is extremely slow growing, taking around 40 years to reach maturity. The trees are also very vulnerable when they’re young. ‘The survival rate for the mahoganies was quite low, about 25 per cent – they had a tendency to be smashed quite easily by hurricanes and what have you,’ Silverstone explains.
As we move around our plot, we certainly come across plenty of very sick looking mahogany trees. Well, actually, trees is probably being a bit generous – some of them are still mere saplings, despite being at least a decade old.
Hence, the team are experimenting with other timber varieties. Chief among these is blue mahoe, a tree that produces an unusual blue-grained wood and matures considerably more quickly than mahogany, reaching commercial size in around 15 years.
‘The mahoe have been much more successful than the mahogany,’ Silverstone tells me. ‘But on the other hand, mahogany is a well-known and valuable wood. The trouble with the mahoe is, it’s relatively unknown. And we’re having to pioneer it as an acceptable hardwood. Woodworkers are very conservative people – if they don’t know a wood well, they’re very cautious about using it.’
LINE DANCING
Rather than scattering the trees around the forest, the researchers planted them in neat rows. This helps with finding them – which, as we discover, can be surprisingly difficult now
that a thick understorey has grown up around them – but was carried out more with their eventual extraction in mind.
‘What we’re doing is trying to mimic natural tree falls, but doing it in an orderly fashion,’ Silverstone explains. ‘One thing you have to remember about these plantations is that you have to get the wood out somehow.
And if you have a little group of trees here and a little group there, you’re going to have a lot of difficulty going in and harvesting them without causing havoc. What we hope to be able to do is to use directional felling to take the trees down in a line – it should be possible to take them down like dominoes, one after the other.’
The team hopes that, as well as acting as a ‘proof of concept’ for using hardwood cultivation for rainforest preservation, the project will help to stimulate the local timber industry. ‘Puerto Rico imports nearly all of its timber – and it shouldn’t have to,’ Silverstone explains. ‘It has the resources to produce its own timber, but there just isn’t an industry on the island – everything comes in from the USA and Canada.’
With this in mind, they’ve been active in trying to involve local people in what they’re doing. ‘Over the past year or two, we’ve started to have a lot of interaction with the locals – with our neighbours, with local projects, but especially with the forestry department,’ Silverstone says.
‘The project has been very quiet for a very long time – we’ve just been sitting waiting for the trees to grow,’ she continues. ‘But now that we’ve got some production, people are starting to show a lot of interest – coming back and looking at what we’re doing and saying, “Wow, someone actually did this.”’
Because the overarching aim is to make the land as profitable as possible without removing the rainforest, the team is also assessing the suitability of a variety of other plants for growing either within the timber plots or elsewhere in the forest. ‘We’re looking for shade-tolerant crops with a high market value, such as coffee and cocoa,’ Silverstone explains. ‘We’re also looking at medicinal plants. One of the crops we’re planning to work with is artemesia, a plant that’s used in the treatment of malaria.’
There is actually a history of coffee cultivation in this forest. ‘We still see lots of old coffee trees scattered about,’ Silverstone says. ‘That’s probably why we have some handsome forest. They used to raise large trees to shade the coffee plants.’
Since my visit, this work has begun, with 450 coffee seedlings from three varieties now planted, along with 150 artemesia plants. Work has also started on determining what other economically valuable non-timber products are present in the forest, in particular vines for weaving and handicrafts.
ANIMAL MAGIC
But the project isn’t just about plants. The team is also interested in what effect, if any, planting the timber is having on the forest’s inhabitants. At the time of my visit, that meant frogs. ‘Frogs, believe it or not, are key predators in this forest,’ Silverstone explains. ‘So we know that if we have a healthy frog population, we know that we’re not doing too much damage to the biodiversity of the forest.’
Now, in my experience, assessing frog populations generally means walking along a transect at night looking for adult or sub-adult frogs sitting out on the vegetation. But not here. The technique being used at Las Casas is more akin to police doing a ‘fingertip’ search for a murder weapon. Everyone gets down on their hands and knees and rummages through the leaf litter looking for juvenile frogs, while also checking the vegetation for larger individuals.
We’re searching for two species – members of the world’s most diverse vertebrate genus, Eleutherodactylus, which currently contains more than 700 known species, with more added every year. The species in question are E. coqui and E. wightmanae. The former are known as common coquís – an onomatopoeic name that derives from their call: ‘Co-kee, co-kee.’ These frogs are so ubiquitous in Puerto Rico that they’ve become an unofficial national symbol.
Like other Eleutherodactylus, both of these species forego the tadpole stage, emerging from the egg as fully formed froglets; fully formed, very small froglets, less than a centimetre in length. And it’s these that we’re rummaging around in the leaf litter after.
It doesn’t take long – the forest floor is teeming with the little blighters – and the searchers are soon calling out each discovery to the data recorders. The results of this research have since been analysed, and although the relative abundance of the frogs was slightly higher in the undisturbed forest, the difference wasn’t statistically significant, suggesting that line-planting hasn’t had a major effect on the amphibians.
The team is now carrying out a similar study of the forest’s lizard community – which is made up primarily of members of the genus Anolis (pictured below left), small, insectivorous, mostly arboreal lizards – attempting to establish which species are present in the forest, their densities, their habitat preferences and whether they’re affected by the forestry activity.
LONG-TERM VIEW
The project still has a long way to go. The mahogany trees are still around 15 years away from maturity and the work on non-timber products is still in its infancy. There are also issues with the road that snakes through the property. Overgrown and, in places, partially blocked and washed away by landslips, there’s no way that it’s going to be able to accommodate the big logging trucks that will be required to get the timber out.
‘We still haven’t totally proved this concept yet,’ Silverstone says. ‘We’re on stage two: we’ve done the planting and we’ve done the waiting for the trees. The next five to ten years will be very telling because now we’re at the stage where we have to do the harvesting, we have to do the marketing, we have to do the replanting, and see if we can get the whole thing working again.’
The next volunteer trip to Las Casas de la Selva leaves on December 11. Anyone interested in taking part should visit www.earthwatch.org/europe
For more information about the project, visit www.eyeontherainforest.org
September 2008
‘Ready.’
‘Tree J, DBH, 52.’
‘52. Got it.’
‘Data?’
‘Ready.’
‘Tree K, canopy, east–west, 137.’
‘137. Got it.’
Enveloped in the soothing green of the Puerto Rican rainforest, I listen as the voices ring out from the gloom – my team mates busily gathering, communicating and recording information about the trees that surround us. We’re methodically making our way around a one-acre (4,047-square-metre) plot, measuring a collection of variables for each tree: height, diameter at breast height (hence the DBH above), spread of the canopy and so forth.
The terrain is steep and – following a few nice, heavy tropical downpours – satisfyingly muddy, but thankfully, the rainforest is quite spectacularly benign. Having spent several years conducting research in the rainforests of north Queensland, I had been steeling myself for the inevitable experience of being bitten by mosquitoes, stung by wasps, bled dry by leeches, and punctured and/or lacerated by the local trees, shrubs and vines. But apart from some appropriately named razor grass and a tree fern that’s armed with needle-sharp spines, there seems to be very little here that’s out to do me damage.
Interspersed among the various indigenous species are rows of considerably more valuable trees: young mahoganies, their straight trunks reaching up into the thick canopy. It’s these trees that have brought me and my team of fellow volunteers here to Patillas, Puerto Rico – they form the heart of a unique project aimed at finding new ways to conserve tropical rainforest.
VALUE ADDED
One of the classic strategies proposed for the preservation of rainforest is to make it more profitable to keep than to cut down. Much of the world’s remaining tropical rainforest
is found in developing nations, where preserving forest for its own sake is a luxury that most people can’t afford.
A variety of ways of achieving this goal have been suggested and attempted, from ecotourism ventures to the collection of forest products such as fruits and nuts. But each has struggled to provide enough of an income for the people who live in and around the forest.
The approach here is to grow high-value timber, primarily mahogany, within the forest itself. ‘The idea,’ explains Sally Silverstone, the project’s principal investigator at the time of my visit, ‘is to demonstrate alternative uses for the forest and find ways that we can make money off rainforest property while, as far as possible, leaving the biodiversity intact.’
The project is being carried out in the 409-hectare Las Casas de la Selva forest, a privately owned block of old secondary tabanuco rainforest about an hour’s drive from the island’s capital, San Juan. Keeping this forest intact is about more than just preserving the biodiversity. In this part of Puerto Rico, there is still significant clearing of land for agriculture and livestock grazing, and because the terrain is very steep – generally 30–45 degrees in slope – this results in severe erosion.
‘The property was bought during the early 1980s with the help of the Puerto Rican Department of Natural Resources, which was very keen for us to set up this demonstration project and to do it here at Patillas,’ Silverstone continues. ‘We’re on the southern border of the Carité National Forest. And because they knew that we wanted to keep the forest intact, they saw us as a buffer to the national forest.
‘We purchased several small pieces of property and put them together – mostly land that had been under cultivation during the 1920s and ’30s but was abandoned during the 1940s as people moved to the cities.’ The initial timber planting, which began in 1983 and continued until the early 1990s, involved about 40,000 mahogany, blue mahoe and other valuable native hardwood trees, spread out over an area of around 87 hectares at an elevation of about 500–600 metres.
The trees were then simply left alone to grow, before the researchers returned in 1997. ‘We wanted to come back and see what had happened,’ Silverstone says.
Silverstone and her team then embarked on an intensive research programme, evaluating everything from the growth and success of the trees to the effect that the planting has had on the local biodiversity. ‘What we want to do is prove the whole cycle – do the planting, the harvesting, the replanting – and really show that we can get it onto a continuous, sustainable cycle of harvesting, replanting, harvesting, replanting, so that it yields so much in every year but is done in a gentle and sustainable way without causing too much destruction,’ she explains.
‘Obviously, one of the key things here is that your crop has to be fairly valuable, because the work is going to be labour-intensive and it’s a long wait,’ Silverstone continues. ‘So you have to have something that you know is going to have a good selling price.’
Although very valuable, mahogany is extremely slow growing, taking around 40 years to reach maturity. The trees are also very vulnerable when they’re young. ‘The survival rate for the mahoganies was quite low, about 25 per cent – they had a tendency to be smashed quite easily by hurricanes and what have you,’ Silverstone explains.
As we move around our plot, we certainly come across plenty of very sick looking mahogany trees. Well, actually, trees is probably being a bit generous – some of them are still mere saplings, despite being at least a decade old.
Hence, the team are experimenting with other timber varieties. Chief among these is blue mahoe, a tree that produces an unusual blue-grained wood and matures considerably more quickly than mahogany, reaching commercial size in around 15 years.
‘The mahoe have been much more successful than the mahogany,’ Silverstone tells me. ‘But on the other hand, mahogany is a well-known and valuable wood. The trouble with the mahoe is, it’s relatively unknown. And we’re having to pioneer it as an acceptable hardwood. Woodworkers are very conservative people – if they don’t know a wood well, they’re very cautious about using it.’
Start the slideshow (5 pictures)
LINE DANCING
Rather than scattering the trees around the forest, the researchers planted them in neat rows. This helps with finding them – which, as we discover, can be surprisingly difficult now
that a thick understorey has grown up around them – but was carried out more with their eventual extraction in mind.
‘What we’re doing is trying to mimic natural tree falls, but doing it in an orderly fashion,’ Silverstone explains. ‘One thing you have to remember about these plantations is that you have to get the wood out somehow.
And if you have a little group of trees here and a little group there, you’re going to have a lot of difficulty going in and harvesting them without causing havoc. What we hope to be able to do is to use directional felling to take the trees down in a line – it should be possible to take them down like dominoes, one after the other.’
The team hopes that, as well as acting as a ‘proof of concept’ for using hardwood cultivation for rainforest preservation, the project will help to stimulate the local timber industry. ‘Puerto Rico imports nearly all of its timber – and it shouldn’t have to,’ Silverstone explains. ‘It has the resources to produce its own timber, but there just isn’t an industry on the island – everything comes in from the USA and Canada.’
With this in mind, they’ve been active in trying to involve local people in what they’re doing. ‘Over the past year or two, we’ve started to have a lot of interaction with the locals – with our neighbours, with local projects, but especially with the forestry department,’ Silverstone says.
‘The project has been very quiet for a very long time – we’ve just been sitting waiting for the trees to grow,’ she continues. ‘But now that we’ve got some production, people are starting to show a lot of interest – coming back and looking at what we’re doing and saying, “Wow, someone actually did this.”’
Because the overarching aim is to make the land as profitable as possible without removing the rainforest, the team is also assessing the suitability of a variety of other plants for growing either within the timber plots or elsewhere in the forest. ‘We’re looking for shade-tolerant crops with a high market value, such as coffee and cocoa,’ Silverstone explains. ‘We’re also looking at medicinal plants. One of the crops we’re planning to work with is artemesia, a plant that’s used in the treatment of malaria.’
There is actually a history of coffee cultivation in this forest. ‘We still see lots of old coffee trees scattered about,’ Silverstone says. ‘That’s probably why we have some handsome forest. They used to raise large trees to shade the coffee plants.’
Since my visit, this work has begun, with 450 coffee seedlings from three varieties now planted, along with 150 artemesia plants. Work has also started on determining what other economically valuable non-timber products are present in the forest, in particular vines for weaving and handicrafts.
ANIMAL MAGIC
But the project isn’t just about plants. The team is also interested in what effect, if any, planting the timber is having on the forest’s inhabitants. At the time of my visit, that meant frogs. ‘Frogs, believe it or not, are key predators in this forest,’ Silverstone explains. ‘So we know that if we have a healthy frog population, we know that we’re not doing too much damage to the biodiversity of the forest.’
Now, in my experience, assessing frog populations generally means walking along a transect at night looking for adult or sub-adult frogs sitting out on the vegetation. But not here. The technique being used at Las Casas is more akin to police doing a ‘fingertip’ search for a murder weapon. Everyone gets down on their hands and knees and rummages through the leaf litter looking for juvenile frogs, while also checking the vegetation for larger individuals.
We’re searching for two species – members of the world’s most diverse vertebrate genus, Eleutherodactylus, which currently contains more than 700 known species, with more added every year. The species in question are E. coqui and E. wightmanae. The former are known as common coquís – an onomatopoeic name that derives from their call: ‘Co-kee, co-kee.’ These frogs are so ubiquitous in Puerto Rico that they’ve become an unofficial national symbol.
Like other Eleutherodactylus, both of these species forego the tadpole stage, emerging from the egg as fully formed froglets; fully formed, very small froglets, less than a centimetre in length. And it’s these that we’re rummaging around in the leaf litter after.
It doesn’t take long – the forest floor is teeming with the little blighters – and the searchers are soon calling out each discovery to the data recorders. The results of this research have since been analysed, and although the relative abundance of the frogs was slightly higher in the undisturbed forest, the difference wasn’t statistically significant, suggesting that line-planting hasn’t had a major effect on the amphibians.
The team is now carrying out a similar study of the forest’s lizard community – which is made up primarily of members of the genus Anolis (pictured below left), small, insectivorous, mostly arboreal lizards – attempting to establish which species are present in the forest, their densities, their habitat preferences and whether they’re affected by the forestry activity.
LONG-TERM VIEW
The project still has a long way to go. The mahogany trees are still around 15 years away from maturity and the work on non-timber products is still in its infancy. There are also issues with the road that snakes through the property. Overgrown and, in places, partially blocked and washed away by landslips, there’s no way that it’s going to be able to accommodate the big logging trucks that will be required to get the timber out.
‘We still haven’t totally proved this concept yet,’ Silverstone says. ‘We’re on stage two: we’ve done the planting and we’ve done the waiting for the trees. The next five to ten years will be very telling because now we’re at the stage where we have to do the harvesting, we have to do the marketing, we have to do the replanting, and see if we can get the whole thing working again.’
The next volunteer trip to Las Casas de la Selva leaves on December 11. Anyone interested in taking part should visit www.earthwatch.org/europe
For more information about the project, visit www.eyeontherainforest.org
September 2008
|
FIND OUT WHAT WE'RE TALKING ABOUT ON TWITTER:
| |
 |
