TY  - BOOK
AU  - Wahlenberg, W.G.
TI  - Investigations in weed control by zinc sulphate and other chemicals at the savenac forest nursery 
U1  - P 632.5 21st ed.
PY  - 1930///
CY  - Washington
PB  - United states Department of Agriculture
KW  - Forest Nursery
KW  - Zinc sulphate
KW  - Chemicals
KW  - Development of pine
KW  - Tree species
N1  - Technical Bulletin No. 156
ER  -