I suggest using Drones. They've been used successfully in other low resource countries for fighting forest crime. A single drone can cover much more area than an officer on the ground. Native tribes are starting to use them in different places to protect their territory.
Okay, can you vaccacinated the trees- make them useless to lumberjacks? As in give them a bad scent, taint them with a colour, so that they are visibly not worth anything to the market, without cutting them down?
Yes. You can drive ceramic spikes into random trees across a forest.
If you drive them at a low height, it will break chainsaws, and disrupt lumber operations. If you drive them at a higher height, it won't disrupt the harvesting, but will produce a truly spectacular surprise at the sawmill that processes the lumber. If done a few years before logging operations, it is almost undetectable.
Having a $10,000 sawblade ruined, and a work line being taken out of service until the blade can be replaced seriously sours lumberyards on the prospect of dealing with spiked wood.
Of course, the spikers will be called lunatics, eco-terrorists, communists, job-killers, worker-killers, and every possible effort will be taken by the authorities to hunt them down like dogs. Tree spiking is a felony in the United States, and, given the track record of how resource firms tend to deal with environmental/native/land rights activists in developing nations (quickly, and violently), is almost certainly a 'needs killin' offense' in much of Central and South America.
