Commercial charcoal production production is illegal in the DR because it destroys the forest. In fact if you buy a piece of property, clearing the trees on the lot can involve some legal hoops to jump through. The reason why can be seen from space: the Dominican/Haitian border can be made out where charcoal production is allowed by the barren landscape of Haiti.
Ironically, the DRs policies about producing charcoal has made the problem worse in Haiti. Haitians produce charcoal near the DR border and then smuggle it into the DR where it is still cheaper than propane as a cooking fuel. Some Dominican dishes, like chicken carbon are also much more flavorful when cooked over a charcoal fire.
Charcoal production is at the core of Haiti's environment problems, and the urbanization of their population has made it much worse. On rural subsistance farms, a fire can be tended by a child feeding it finger-sized wood. But unseasoned wood creates much more smoke than charcoal and it is far heavier to transport. This makes charcoal the preferred cooking fuel in cities. But in the production of charcoal, some 70-80 percent of the wood's heating potential is lost. In other words, about four times as much green wood has to be harvested to cook a meal when someone moves to the city.
The branches only can be harvested as a sustainable cooking fuel for green wood fires in a process called
coppicing, but in charcoal production, whole trees are cut down to get larger chunks of charcoal and less loss in the production process. In many areas of the DR, you can see "living fences" where a tree has been cut back to its trunk for the branches and new growth coming out of it.
Cooking fuel is still a major concern in Haiti. I'm of the opinion that the US should provide charcoal produced from agricultural waste free to Haiti to make the charcoal industry no longer profitable. Propane won't work since few Haitians can afford a propane stove and propane itself is much more expensive than charcoal. One possible answer would be for the US to make charcoal out of corn cobs to export to Haiti:
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