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ARS Home » Southeast Area » Fort Pierce, Florida » U.S. Horticultural Research Laboratory » Subtropical Plant Pathology Research » Research » Publications at this Location » Publication #335683


Location: Subtropical Plant Pathology Research

Title: CHMA Design: Performance Review, Concerns, and a Risk-based Optimization for Treasure Coast Areas in Florida

item Gottwald, Timothy
item LUO, WEIQI - North Carolina State University

Submitted to: Journal of Citrus Pathology
Publication Type: Abstract Only
Publication Acceptance Date: 12/20/2016
Publication Date: 5/18/2017
Citation: Gottwald, T.R., Luo, W. 2017. CHMA Design: Performance Review, Concerns, and a Risk-based Optimization for Treasure Coast Areas in Florida. Journal of Citrus Pathology. 4(1):25/45.

Interpretive Summary: Citrus Health Management Areas (CHMAs) have been proven as a viable management strategy in suppressing ACP populations and slowing HLB spread in FL. Such a management strategy can be adapted and improved for the Treasure Coast area which had poor control of ACP in 2014. Through simulation and optimization, seven new CHMAs are proposed which were constructed with consideration of several known HLB/ACP risk factors plus growers’ ownership, grove size, management and logistics concerns.

Technical Abstract: Compared with the 48 officially recognized CHMAs in FL, the Treasure Coast area exhibited very poor control of ACP in 2014 where multiple ACP ‘hot spots’ (i.e. extremely high ACP counts) were recorded. The number of abandoned groves and uncoordinated spray patterns can lead to increasing ACP pressure. Without CHMA-wide control, HLB will spread quickly and the implications for new tree plantings may not be viable for production. A series discussion among Indian River Citrus League (IRCL) growers was held to assist in the development of CHMAs for Treasure Coast Citrus that integrate ACP control into new planting plans. Based on our risk models, many risk factors are considered in the Treasure Coast CHMA optimization including: ACP population dynamics, residential risk (e.g. proportion of human population in the landscape), abandoned groves, distance to transportation corridors, citrus nurseries, farmers markets, packing houses and green waste facilities. Other logistical concerns are also considered, such as commercial planting density, maximum/optimum number of growers per management area and elevation difference for movement of equipment. Following thousands of simulations and optimization, seven CHMAs are proposed for the Treasure Coast area. They are defined as Indian River North, Indian River South, 95 East, Okeechobee, St. Lucie West, East and South. The generated CHMA maps have been shared with growers via UF/IFAS extension ( to monitor ACP control performance locally and statewide.