treatment_code	Amendment description
A	No organic material, bare fallow No N
B	No organic material No N
C	No organic material 80 kg ha N as calcium nitrate
D	No organic material 80 kg ha N as ammonium sulphate
E	No organic material 80 kg ha N as calcium cyanamide
F	Straw No N
G	Straw 80 kg ha N as calcium nitrate
H	Grass/green manure (no leguminous plant matter) No N
I	Moss peat No N
J	Manure No N
K	Manure with superphosphate, No N
L	Sawdust from conifers, No N
M	Moss peat 80 kg ha N as calcium nitrate
N	Sawdust 80 kg ha N as calcium nitrate
O	Sewage sludge No N