Start with high-confidence crop science books, then narrow by subgenre or adjacent topics.
Soil Science Simplified
Neal S. Eash, Thomas J. Sauer
Modern Crop Protection Compounds, 4 Volume Set
Peter Jeschke, Clemens Lamberth
Modern Crop Protection Compounds, Volume 1
Modern Crop Protection Compounds, Volume 2
Modern Crop Protection Compounds, Volume 3
