It has never been easy to say where agriculture stops and forestry starts. Many governments call some areas "forest land" even though there aren’t any trees and farmers grow crops there. Most people consider livestock part of agriculture, but millions of farmers graze cattle in forests. Agroforestry is stuck somewhere between agriculture and forestry and has never found a real home in either.

Now things are getting even fuzzier. People increasingly use "agricultural" crops to make "forestry" products. Each year Malaysia and Thailand export almost 1.5 billion dollars of furniture made from rubber trees, and coconut palms supply more than an eighth of the timber used by Filipinos. Fruit trees like mangos, tamarinds, and jackfruits provide much of the wood in Sri Lanka and the Indian state of Kerala. In the future, a significant share of Asia’s particleboard and fiberboard may come from tree crops, bamboo, straw, and sugar cane.

Admittedly, this phenomenon is not entirely new. The Chinese have made most of their paper from straw and other crop residues for centuries. Nonetheless, we are likely to see more of this as natural forests run out of wood, old tree crops need replacing, and new processing techniques open up all sorts of fresh possibilities for using raw materials. Right now Southeast Asia has enough old rubber trees to be able to harvest more than 6.5 million cubic meters of wood each year. That practically equals the entire timber harvest of Central Africa.

You can read about all this in "Asia’s New Woods", by Pat Durst, Wulf Kilmann, and Chris Brown from the FAO, published recently in the Journal of Forestry. As they tell the story, any day soon people may start making doors and windows from tomatoes!