The Inga trees in the first plot that we planted at the end of February 2014 have been big enough to pollard since July. We have not pollarded, however, as the conditions have not been right to do so. As Dr Terry Pennington, Inga agroforest expert explained, you should not pollard trees during the dry season and the best time to do so is a couple of weeks into the wet season. The reason for this is that when you remove all of the leaves and main branches of a tree, the above-ground loss is mirrored below ground. That is the roots die back comensurate with what was lost above. During the dry season there is little water in the soil and the tree needs all its roots to obtain the moisture it needs. Therefore if you have pruned during the dry season, the tree is left without enough roots to survive.
In the case of the Bolivian Amazon, the dry season normally runs from April/May to October/November. This year has been particularly hot and dry, possible a consequence of the El Niño phenomenon, and so pollarding our plot would likely kill all of the trees. We will therefore wait until the middle of November when the rains should have started before pollarding.
At another of our sites, Palacio, the timing of pollarding is also important. The reason for this is that it is a site which floods for a couple of weeks each February. We therefore have to be careful that we leave enough time between pollarding and the floods. Or at least make sure that we pollard high enough so that the new shoots emerge above the floodwaters. So here again the timing of pollarding and the associated planting of crops needs careful thought!