Monday, July 18, 2011

In the Forest of Good and Evil

There is a decades old problem in Philippine reforestation. We have been using non-native species to regreen our forests because these exotic species are previously known to be fast growing and would do the job with quick visible results. We thought because we filled the gaps with trees (regardless what these trees are), we solved the problem. Thus we find introduced species like mahogany, gmelina, ipil-ipil and knife acacias encroaching to our protected areas housing our native flora and fauna. Little do we know that they disrupt the fragile ecology of our delicate endemic species. Little by little, the spaces that our native species were occupying are slowly being replaced by these exotics. And the government continues to do so till this day.

One fine example is Bohol's manmade forest. This forest of the non-native mahogany (Swietenia macrophylla) is considered one of the province's major tourist attractions. It is a source of pride as it is a living proof of Bohol's accomplished environmental project. It was in 1968 when the local government asked students to plant the mahogany seedlings to reforest a portion of Billar town. Forty years after, the seedlings have grown to considerable size, forming a forest dominated by a single introduced species.

I remembered uttering the phrase 'parang wala ka sa Pilipinas' (as if you are not in the Philippines) when I first caught glance of the manmade forest. Now I understand why. It reminded me of a temperate zone woodlands where single or only a few species dominate because of low biodiversity. The usual Philippine rainforest would have a varied selection of trees as it has high biodiversity. But because the government is still maintaining the dominance of the mahogany, the native species are given less chance to repopulate the area. Fallen mahoganies are replaced with mahogany seedlings rather than letting the native species get a foothold and reestablish themselves.

But upon closer look, the native species are undoubtedly trying their best to reemerge. Native Pandanus species seedlings are growing under the shade of the tall mahoganies. Celtis seedlings are waiting for their chance to get their share of sunlight, which is hogged by the tall exotics. Osmoxylons are trying their very best to survive, trying to get whatever share of filtered light they could steal from the thick canopy. The natives are there patiently waiting.

If the Bohol people only planted native species in 1968, the manmade forest would have boasted large specimens of dipterocarps or perhaps kamagong by now and not these introduced mahoganies. Probably sometime in the future the locals would grow tired of maintaining the dominance of this exotic species. Hopefully when it happens, the dipteros and the natives like kalingag liitan, binunga, molave, antipolo and a selection of others would reclaim the land and repopulate. The great diversity of large native species would have been a better spectacle to see than the monotonous tall mahogany trunks visible in the manmade forest.

12 comments:

Romher Jude Quilantang said...

Nice to learn about this, Patrick! Now my mahogany forest shots from Bohol sadden me.

metscaper said...

I am sure the memories of your trip are still great, Romher.

metscaper said...

Pat Malabrigo in my Facebook said that the species pictured here is not a Cinnamomum but rather a Celtis philippensis. Thanks for the correction, Pat.

mutant_onionoid said...

Call me an extremist, but is it legal to cut down all of these mahogany trees and then replace them with native ones? Then we could use the wood from the mahogany while the native trees thrive?

metscaper said...

In my opinion, probably best to leave them as they are. But if they do fall, they should not be replaced with mahoganies anymore, but with native species.

Tungol said...

Pat, maybe we can start writing a campaign to local government units in bohol to create an awareness of planting native trees. We can still make a difference.

Ernie said...

I was told by one of our tourist guide that one of the downside of this man-made mahogany forest was the lack of animals and birds living inside the forest. This according to him was brought about by the lack of fruits or food inside the forest that the animals or birds can eat.

metscaper said...

wow. sayang kung walang animals. sana bahay na yun ng tarsier.

maknavarez said...

I just remembered, about this wonderful tree that we have here in Olongapo and Subic Bay; the Siar Trees (peltophorum pterocarpum). Please go to this link:
http://bloggapo.blogspot.com/2011/04/siar-trees-peltophorum-pterocarpum-in.html
--I love checking blogs related to my interests; lemme just share you a story about how I've found pages like this. The link am asking you to check is also a blog page where he writes stuff about our very own local place, Olongapo. I was looking for the name of this tree that has been brought down coz of typhoons that hit Luzon months ago this 2011. so I gave it a try, googled the description and took me to Vanishing Points Blog page. Very interesting page.
and then, as I was looking for Mahogany trees, just because I lived once in a street called mahogany just by the foot of the mountain in Brgy. Barretto in Olongapo, then it took me to your page same time I learned how facsinating ur page is sir. You people doing these stuff are great. sabi nga ni ama, "mahusay!"

metscaper said...

I'd love to check other sites too. Hope my time would allow, but as of the moment i have to check my students' plates.

mujacko2002 said...

Mabuhay!

I just have this lingering thought about tree planting : Mas pricey ba ang local species of trees rather than those mahogany/ipilipil/acasia etc.?

dimple marie said...

When will we ever learn? just recently news about planting Cherry Blossoms in Benguet went viral. The purpose of which is to boost tourism in the area- good intention but poor action. Introduction of exotic species is detrimental to the balance in nature. Such as the situation above, the man made forest is technically not a forest it is a mahogany stand. In the area you can barely see other tree species growing because Mahogany is one hell of a murderer tree. It gives off chemicals that inhibits the growth and development of species surrounding them termed as allelopathic effect. And how do you think is Brontispa longissima- one of the most damaging pest in coconut was introduced in the Philippines? it is through the importation of Palm trees used as ornamental along Roxas Boulevard. it spreads because of lack of natural enemies and abundant supply of food in our country... therefore next time guys we decide to conduct tree planting activities let use plant Endemic species... DENR have variety of species to provide just visit its local offices.. :)