Six months after installation, sub-samples of leaves from the
upper one-third of seedlings were collected for each treatment
within each block at both sites. At least ten leaves were collected
and combined to form one composite sample for each treatment
within a block. The same was done for phyllodes at Pahala; phyllodes
were not present on seedlings at Volcano at the time of collection.
The combined samples were air-dried to a constant mass at
18.3 C before grinding them with a Wiley Mill using a 20-mesh
screen. The samples were submitted to A & L Great Lakes Laboratories
(For Wayne, IN, USA) for foliar nutrient analyses. Foliar N concentrations
were obtained by combustion using the Dumas
procedure (AOAC 968.06) in a LECO nitrogen analyzer