Satsuma Orange Tolerance to Spring and Autumn Indaziflam Applications in Georgia

Abstract

Citrus is a major crop in the SE US, with groves located primarily in Florida, but adapted cultivars have allowed for the expansion of commercial production into the Coastal Plains region of Georgia. Indaziflam, a cellulose biosynthesis inhibiting residual herbicide, controls numerous grass and broadleaf weed species. Research conducted in Georgia from 2020 to 2022 determined the optimal rate and tree response to indaziflam applications. Biannual treatments applied in April and November in established satsuma citrus groves included residual herbicides indaziflam, flumioxazin, diuron, pendimethalin, simazine, and norflurazon. The data indicated no negative impact on tree diameter growth over 30 months after application initiation. Indaziflam provided residual activity in the first year with >80% weed control for bermudagrass and pink purslane and >70% of cutleaf evening primrose, cutleaf geranium, and wild radish. Greater than 69% of weed control was maintained with indaziflam after sequential application for 2 years. All other herbicides provided inadequate residual weed control. Indaziflam PRE applied in citrus groves in Georgia can provide growers with a reliable herbicide option that has been proven to be safe for trees and season-long weed control.

Keywords

• satsuma orange
• <i>Citrus unshiu</i> Marc.
• soil residual herbicides
• weed control