The trees are the primary producers that produces the food on which the consumers are dependent. This forms the base of the ecological pyramid for both energy as well as biomass.
In any biological condition, it can be observed that during its ecological succession from one trophic level to the next, almost 90% of its total energy is lost, and only 10% of its energy is transferred to the successive trophic level.
Similarly, biomass is also comparatively higher in producers like plants and trees than in any other trophic levels.
Assuming the options found elsewhere, one of the achievements of pre-Columbian (i think you mean Mesoamerican, not "mess") cultures would show that they had intensive architecture, which they sustained through intensive agriculture.
