As temperatures increase across Florida, so does the risk for huanglongbing (HLB) disease, known as citrus greening.
While the southern and central portions of the state remain vulnerable to HLB and Asian citrus psyllids (ACP) that spread the disease, growers in North Florida and South Georgia have so far been spared.
But Xavier Martini, University of Florida entomologist at the North Florida Research and Education Center (NFREC), cautions growers to stay alert and keep an eye on potential new infestations. It is important to scout trees for HLB symptoms.
No case of citrus greening has been observed in commercial groves west of the Suwannee River. Citrus growers in that area want to keep it that way.
“This success can be credited to ACP early detection, rapid eradication of the population and removal of infected trees when possible,” Martini said in the April 2021 issue of the Cold Hardy Citrus Connection newsletter. “In the war against HLB, early detection is key. ACP adults tend to aggregate on flush, and ACP nymphs only feed and develop on them. Those flush should be the prime focus of any sampling effort against ACP.”
Martini says growers need to sample at least 10 flush on 20 different trees on each border of the grove. A local Extension agent should be notified immediately if psyllids are discovered. If psyllids are found, it is recommended that any citrus within a 5-mile radius be sprayed as well as other groves where workers may have traveled.
In short, Martini recommends a five-point strategy to preserve groves:
- Scout your grove regularly, especially between June and November.
- Act accordingly. If you find Asian citrus psyllids, do not wait. Treat with a foliar application. Scout your grove a week later to see if application has worked.
- Find trees with HLB. Send any suspicious samples to the plant clinic at NFREC.
- Educate your neighbors and colleagues about the need to control ACP and to monitor for HLB.
- Remove any tree immediately that is positive for citrus greening.