Assertion: cowpea's nitrogen | /r/HasProperty | kjeldahl method
Facets:
Source sentences:
text: The soils from each experimental field were bulked together, and subsamples analyzed for chemical properties such as pH (H 2 O), organic carbon  , total nitrogen (Kjeldahl method), P using Bray-2  , K, Na, Ca, Mg, S, and cation exchange capacity (CEC) using ammonium acetate method (Table S1).