After a meeting yesterday at the OUCE in Oxford, we all suggest to add a Replacement Rotation to the in-growth core protocol in the manual:
As has been discussed here before (Terhi, Chris and Dan Aug/Sep 2012: http://gem.tropicalforests.ox.ac.uk/postings?resource=ingrowth-cores ), over the course of time, in-growth cores become degraded: some soil is lost at each excavation and repeated searching through the core fragments the soil structure. So, we suggest to arrange a rotation so that 25% (i.e. 4 under the standard protocol) of the in-growth cores are replaced with new cores (at least 1 m away) every three months. At changeover, excavate the old core as before but discard the soil into the old core hole, dig a new hole and set up a new in-growth core there using the same cage. This has the added advantage of giving regular root stock data from new locations each time.
Does anyone have any comments about this new requirement? Is anyone already doing this? Any suggested modifications?