Dear Growers and Friends,
So far, Coffee Leaf Rust (CLR), the world’s most important and devastating disease of coffee, has been officially found on Maui and tentatively on the Big Island (Hilo and Kona). Please check your coffee tree leaves for signs and symptoms of this fungal pathogen. An HDOA field guide and submission form can be found here and below.
Proper application of fungicides is critical for the suppression and management of CLR. Please read through the “Spraying to Suppress Coffee Leaf Rust” publication carefully. Fungicide product rotation is especially important for reducing the risk of CLR becoming resistant to approved products. Whenever handling, mixing, and applying pesticides, read the product label completely and follow all directions provided on the label. This is an updated publication from that you may have received earlier today (Nov. 4). Please replace the old document with this newer version.
New webpage for Coffee Leaf Rust:
If you have great rust articles and publications you'd like seen available to others via my website, please send them to me for review and posting. I've created a CLR resource page for publications and will keep building upon the information available.
For now, I am postponing on-farm visits because of the risk of spreading CLR. If you have any questions, please contact me via text (415-604-1511) or email ([email protected]). You are welcome to send me photos of leaves with potential CLR; however, send clear photos of the upper and lower surfaces of leaves, and please do not bring suspected CLR leaf samples to the Extension Office for me to look at. At this time, photos only. Thank you.
If visiting other farms, please follow sanitation procedures provided by USDA to reduce the spread of CLR spores to non-infected locations and farms.
Please stay healthy and well.