This project aims at investigating efficacy and feasibility of individual tree covers such as the tree defender to protect the tree from psyllids in the first 2-3 years after planting, and higher capacity nets during productive years. Little is known on the physiology and tree health parameters of trees grown under individual protective covering (IPC). There are no reports in the scientific literature regarding the use of these IPC systems in citrus.The project started in December 2018. We are following the chronology developed in our proposal. Our Project has 4 main objectives: Objective 1. Assessing tree growth and absence of psyllids and HLB disease symptoms (including CLas bacteria titer) under protective covering. Objective 2. Assessment of alternative netting approaches involved in `targeted’, `alternated’ or `patterned’ setup of IPC in groves for more cost-effective protection. Objective 3. Monitoring the transition from vegetative to reproductive stage in the covered trees as compared to the uncovered. Objective 4. Comparing individual tree protection with CUPS-like systems. Objective 1: We continued assessing the trees (Valencia on Swingle) planted in our pilot study 18 months ago for incidence of CLas. Today, virtually all of the uncovered trees in the trial (80-100% depending on the treatment) are already PCR-positive for CLas whereas all trees covered with IPC have tested negative. We have started quantification of leaf drop and compared leaf drop in both treatments; cumulative data of April through June show no significant increase in leaf drop in IPC-covered trees. Objective 2: We have identified a collaborator in southwest Florida to evaluate different layouts of IPCs and compare with the grove that we are setting up in Polk County.Objective 3: We have measured this season’s blooming and are now monitoring fruit set and development. We saw more blooming in uncovered than in covered trees. There are two possible reasons for these observations: 1) we measured more vegetative growth in IPC trees, which is known to delay transition to the reproductive stage, or 2) uncovered trees are more stressed by HLB than IPC trees, which may result in more blooming.Objective 4: We finished planting the trees in our CUPS facility and we started to perform different treatments to study fruit set in ‘Tango’, `SugarBelle’, and `US Early Pride’ trees. These treatments consist of different applications of gibberellic acid for overcoming absence of external pollinators. We will be assessing fruit set and fruit development in the coming months.Outreach, Professional Presentations and Extension Activities:-Citrus Industry, January 2019. “HLB reduction strategies”.-IRCHLB VI meeting, California, March 2019. “Individual Protective Covers (IPCs) prevent young citrus trees from psyllids and infection with CLas, and promote vegetative growth”.-Spring Citrus Field Day at SWFREC April 2019. Demonstration of the SWFREC IPC experimental grove with an attendance of over 60 growers and industry representatives.-FSHS ANNUAL CONFERENCE, Orlando, FL, June 2019. “Effect of Individual Protective Cover (IPC) on Physiology and Growth of Citrus Trees”.-Florida Citrus Industry Annual Conference. Educational Session, June 2019. “Protective Covers on Young Trees”.