Hummert's Helpful Hints is a handy reference to the formulas, calculations and tables that give equivalencies, parts per million, measurements of pH, soluble salt and geometric areas. Also covers fertilizers, irrigation, light and lighting, plant structures & more.
35 pages, illustrated
Informations de publication
- Publié: 1999
- Éditeur: Hummert International
- Dewey Decimal: 640.2
- Bibliothèque ECHO: 640.2 HUM