From Tom’s How Can a Leaf Rust? Roya in Guatemala which I humbly suggest should be required reading for folks in the specialty coffee trade.
See also: JimSeven’s Leaf Rust: End of Days?
Roya — coffee leaf rust — is an increasingly clear marker of the climate change crisis. And it’s devastating.
The knowledge of how to fight Roya, and the money for fungicide, the labor to treat it, and to cut back the trees deals a huge blow to the income and profits of the coffee farm. The real impact is on organic farms, whether certified farms or organic-by-default farms, on casual coffee farmers who have little technical knowledge, and on smallholder farms in general. In a couple crop cycles, Roya unmanaged is the death of the coffee farm.
–Tom Owen
