The importance of leeches and other animals
But when you see leeches rearing up to sniff the air before racing towards your legs like worms on speed, it seems they might even have psychopathic tendencies.
In space, no one can hear you scream. In the rainforest, leeches hear you squeal and they love it.
The little critters almost ruined my first experience of a Sri Lankan rainforest. When the guide was pointing to a rare plant, I was frantically flicking leeches off my socks.
When he explained the delicate ecological system I was busy trying to squash one of its key components. (We did not see any leopards perhaps due to intermittent screams every time a member of the party was attacked by another leech.)
It was not a good start to three months as a volunteer for a conservation charity dedicated to preserving the rainforest; but things can only improve.
I am working for Ruk Rakaganno, the Tree Society of Sri Lanka, as a communications advisor.
The job was arranged through Challenges Worldwide, an Edinburgh-based charity that has been given a small amount of money by the Scottish Government to place volunteers in Sri Lanka.
Ruk Rakaganno, or Ruk Rak as they are affectionately known, had requested someone to help them raise awareness of their work. The tiny organisation was set up in 1975 by a group of nature lovers and still relies on volunteers and what little funding it can get from non-governmental organisations and business.
The aim of the charity is to protect endangered forest by highlighting the value of trees and encouraging the planting of indigenous species. Ongoing projects include maintaining an arboretum set up by an eccentric Englishman north of the hill country and a nursery growing indigenous trees in the south.
At the moment the organisation is also aiding post-tsunami reconstruction by replanting trees on the coast, showing women how to re-establish gardens in resettlement areas and teaching conservation in schools.
But despite growing concern about climate change, the charity felt their voice was not being heard. That is where I come in. My job will be to raise the profile of Ruk Rak through the local and international press.
It all sounded so simple back home but from the moment I was picked up from the airport it has all been a bit of shock. Within hours of arriving a bomb went off in Colombo as fighting continues between the government and separatists in the north of the country.
The office is at the heart of the secure zone so road blocks are common and soldiers stroll the streets outside. The office has one computer and one phone between three staff and no loo roll in the toilet. My colleagues are very kind but hot, sweet tea is not really what you want when it is 32ºC outside and only one fan is working.
One thing is clear, Sri Lankans are far more connected to the natural world than in the west. In the first few days I share a tut tut (three-wheeler taxi) with a weekly shop of curry leaf, lemongrass and coriander plants and my landlady suggest wood apple to cure a dicky tummy.
But despite this green spaces are not being protected. The sweltering heat of Colombo has increased as trees are bull-dozed to make way for housing and erosion on the coast is getting worse as palms are cut down for new hotels.
The Ruk Rak committee of feisty old ladies, business people and ex-pats are genuinely concerned for their country, particularly in the context of global warming, and have bombarded me with botany and ideas for campaigns.
By the end of the week however it has all become a bit of a green-tinged blur and I jumped at my first chance to go south and see the rainforest we are supposed to be protecting – or what is left of it.
At the beginning of the 20th century about 70 per cent of Sri Lanka was covered by natural forest, now it is less than a quarter.
Just a few hours south of Colombo is the Sinharaja Forest Reserve, the last major undisturbed rainforest in the country and a UNESCO World Heritage site.
Having been brought up on David Attenborough documentaries about the Amazon I expected an impenetrable jungle full of howling beasts and creepy crawlies. Well, I was half right. There are certainly beasties in the Sri Lanka rainforest, but there are also people.
On the southern fringes of the forest the constant sound of insects, birds and monkeys are disturbed by the sound of motorbikes coming along the narrow trails. It might disturb any notion of virgin rainforest but for me it only highlighted the importance of protecting the trees to see people tapping the kitul palm [Palmyra Palm] for treacle or using natural medicines.
Our guide explained the useful properties of all the plants but it was his own vegetable patch that was perhaps most impressive. Here he grew ginger, aubergines, rice and various vegetables that I was not even aware existed. The plants not only provide delicious curries for his extended family but a system of biodiversity that needs no weed killers or pesticides and keeps thousands of important species alive, including humans.
I hesitate to use the word tree-huggers because this is a much older symbiotic relationship, but Sri Lankans have an enormous respect for trees. You can see this everywhere you go; from the shady rain trees on the streets to the Bodhi trees growing in the temples.
On the way back into Colombo there are whole stretches of road where destroyed houses and boat wrecks show the lasting impact of the tsunami. But there are also little saplings being planted as efforts continue to return the coast to normal. Markers of hope for Sri Lankans and their precious trees.
Click here to read the article on telegraph.co.uk