First advise is to go for the comprehensive and free overview of markets done by the Ecosystem Marketplace rather than only for market reports by the markets: the greens are all eyes on the climate forests and markets, so you can be sure they collect all the information on earth on the projects and the market processes. Read also PhD theses about the area you aim to invest in, these often provide you with a complete picture.
Carbon credits gained by any tree you plant has to be verified before getting into carbon markets. This verification is actually very expensive but not impossible. Check though that the cost of verification will not eat up your possible profit. Carry out also an extensive research of verifiers and their prices. If you go e.g. to the Chicago Climate Exchange Registry website, you will see which companies verified credits that have been accepted.
There are other smaller unregulated voluntary carbon markets (mostly in the USA), but markets under the mandatory emissions reduction schemes such as the United Nations’ Clean Development Mechanism or the European Union’s Emissions Trading Scheme are not that supreme or not suitable at all for carbon forests credits.
If you decide to jump on this bandwagon, and invest in a project, follow the well-tried paths and continents, it is risky enough not to. Carbon forests are for some poor countries the only hope to survive, therefore they selling out all their existing forests and base their whole economy on the climate forests. However, oversupply of credits will make the price fall so these countries however tempting and green are eventually risky from the investment point of view. Besides, desperate sellers sometimes try to sell the same spot of forest to 60 different buyers online. So if you see very small local brokers or project-based short-term initiatives ending in 5 years time offering you investments in climate forests in far end countries be very cautious, and leave or make sure their system is valid, monitored by some international organization and that your credit will eventually verified and reach any market;
Before investing in any project of this kind, always check what the greens active in the area are saying about the project because they can easily sabotage it or they can actually help you to avoid making a bad investment. Also check what international policies are formulating for the given country at the UNFCC.
Carbon forests must to be maintained for a certain period of time (usually at least for 20 years). Watch out for the regulations and contractual articles in your project for forest fires and unexpected disturbances in the forest, you don’t want to lose your investment because someone did not kill a campfire, do you?
Current scientific research in CO2 circulation shows overwhelming complexity of the issue. Carbon levels are measured at multiply locations: in the biomass, in the soil, in the air at different altitudes, and add the influencing ocean currents and many more factors, constantly revealing new processes and data. So make sure your contracts are fixed for the term and cannot be modified by new scientific findings.
At the level of biomass, science earlier stated that carbon fixation (trees using up the CO2 of the atmosphere) is only significant in young trees, and reach a plateau at a certain point, however, old growth forests lately been proved to continue fixing (carbon sinking). Therefore investing in old growth forests is an option too and might be eventually safer than new plantations, because there is a high chance that those forests are already under some level of nature protection with no access for human activities, meaning that their maintenance is more likely to be ensured (less disturbances).