What is in this article?:
- Commonly used traps apparently not capturing true number of Asian citrus psyllids in Tulare County.
- Growers are urged to employ voluntary best management practices to slow the spread of psyllids.
- Huanglongbing has not been discovered in Tulare County, but some growers fear that day may soon come.
Kevin Severns is urging growers and others involved in the citrus industry to employ strict best-management practices in order to slow the spread of the Asian citrus psyllid in Central California.
Kevin Severns’ message to citrus growers could not have been more well-timed.
The Sept. 23 citrus grower meeting in Dinuba, Calif., where Severns spoke on best management practices growers can voluntarily employ had barely come to a close when Tulare County Agricultural Commissioner Marilyn Kinoshita announced to an audience of about 300 growers, packers and other citrus industry people that another Asian citrus psyllid (ACP) had just been discovered on a trap, this time in the Exeter area of Tulare County’s citrus growing region.
The Dinuba meeting was the second of two large grower meetings held in Tulare County during the summer months to address a growing number of psyllid finds in the county. Its tone was slightly more somber than the first given that ag officials were now using the term “infestation” in their talk to growers and packers: this because several small citrus trees in a residential yard in Dinuba had an estimated 400-500 adult psyllids and nymphs in them.
Growers and packers were also told about regulatory compliance agreements they must enter into because of the quarantine restrictions.
Most troubling for officials is that the yellow sticky traps used to sample bug populations appear to be ineffective at capturing a true representation of psyllid populations in the region.
While three backyard citrus trees in Dinuba were infested with adult psyllids and their nymphs, the two sticky-card traps located on either side of the infested property had managed to capture only one or two psyllids on each trap. It was only after careful inspection of a yard by a keen-eyed ag inspector that the infestation was discovered.
“What concerns us is that these bugs apparently sat in that yard a long time and nobody noticed them,” said Elizabeth Grafton-Cardwell, a research entomologist with the University of California and an expert on the ACP.
“What this means is the yellow sticky cards are not effective in picking up the psyllids,” she continued. “That’s really discouraging.”
The one good bit of news from the Dinuba discovery was that adult psyllids were able to be collected and tested for Huanglongbing (HLB). Those tests came back negative.
While discouraging, the Dinuba psyllid discoveries illustrates Severns’ point that growers and residents play a key role in slowing the spread of the ACP.
“What we’re talking about is not moving the bug from one place to another,” Severns said.