California has recently surpassed 2,300 residential trees to have been infected with Huanglongbing (HLB), and as the number continues to rise so does the worry of many industry members. While HLB has not yet been detected in a commercial grove in California, slowing the spread of this deadly disease relies on the willingness of homeowners and citrus industry members alike to proactively and collectively implement any means possible to limit populations of the Asian citrus psyllid (ACP).
While California has been successful in avoiding a commercial detection of HLB, Florida has not been so lucky. The following letter comes from Pete Spyke, a citrus grower in Florida, who has witnessed the devastating consequences HLB can have on the citrus industry firsthand. As he reflects on his home state’s struggles and learnings, he congratulates California for the work that the Citrus Pest & Disease Prevention Committee, citrus growers, industry members and homeowners have put in throughout the years, noting California “still [has] an excellent opportunity to preserve your citrus industry … by doing what you’re already doing.”
“It can be easy to throw in the towel and feel as though we must come to terms that HLB may take hold of our commercial groves, but if we’re learning anything from our colleagues across the world it’s that we – as California growers – must double down on our efforts and continue forward,” said CPDPC Chairman Jim Gorden. “After speaking with Pete and other growers about their experiences, it’s become clear that California is on the right path and our progress over the years is something to be proud of.”
Dear California Citrus Growers,
Based on my observations and discussions with growers and researchers from Florida, Texas, China, South Africa, Argentina and Brazil, the most successful method of maintaining long term success with fresh citrus production when HLB has become established is to scout and trap groves and residential yards intensively, control ACP, and immediately remove any tree that is identified as infected with HLB. This control method is “exclusion.”
Florida, Texas, Louisiana, Georgia, South Carolina and Mexico didn’t do that, resulting in an endemic infection of HLB. In Florida, the citrus industry is heavily affected; growers need new ways to treat the disease and tolerant plant material.
California heeded good advice and chose a different path, and you still have an excellent opportunity to preserve your citrus industry and backyard citrus trees simply by doing what you’re already doing. At this point, your response has been cost effective and successful in preventing the spread of HLB in backyard trees and commercial orchards. You are to be congratulated!
There’s probably no treatment, product, cultural practice or novel science alternative that will save the California industry if HLB gets loose. Backyard trees everywhere, fragmented ownership, limitations in machinery and capital all stand in the way of “managing” HLB using any known methodology. Citrus trees are not truly tolerant of HLB – many just die in a year or two even with intensive cultural programs. In my observations, those that survive produce inferior, unmarketable fruit.
The positive choice for California is to continue to invest in detection, including finding new technology and maintaining required manpower on the ground. Don’t waiver when removing infected trees immediately to protect the remaining dooryard and commercial trees.
If there are additional investments to make in new science, it may be in the psyllid arena to find ways to reduce population spread. However, people will present proposals for seemingly attractive alternatives to exclusion. Just remember – those kinds of things only have value if the trees already have HLB. If you scout and remove the infected trees, your producing trees and resets won’t have HLB, so your cultural programs, production and your profits will be the same as they are – nothing new will be needed.
Lots of people will try to convince you that it’s more complicated than that. It really isn’t. Good luck!
Pete Spyke
The Orange Shop
Citra, Florida