University of Florida and University of Wyoming researchers have modeled when citrus growers should switch from conventional to HLB-resistant varieties — and the answer isn't straightforward. Their bioeconomic model finds that an 80% resistance efficacy threshold is a critical financial tipping point: only above that level does it make sense for growers to stop chemical spraying before replanting with resistant cultivars. Below 80%, maintaining aggressive insecticide programs remains the better financial move.
The complication is the perennial nature of citrus trees. Unlike annual crops, existing groves can stay productive for years even while diseased, and new plantings take years to reach full yield. That means the financially rational decision is often to delay replanting, even when resistant varieties are available. Grove density, tree age, and the disease status of neighboring operations all affect the math.
For the industry broadly, this research is a reminder that the technical breakthrough and the economic transition are two different timelines. Florida's citrus sector has already hit historic lows in output — the transition to resistant varieties is the clearest long-term path forward, but buyers sourcing Florida citrus should expect a slow, uneven recovery over the coming decade rather than a near-term rebound.