Backyard Orchard News
If you're looking for something to do tomorrow (Saturday, April 16), it's UC Davis Picnic Day, a...
Drone sipping honey at the Harry H. Laidlaw Jr. Honey Bee Research Facility. (Photo by Kathy Keatley Garvey)
I recently started getting serious about studying earwigs in San Joaquin Valley citrus. It seems my timing is great (well, great for research anyway), because there are very high numbers in young tree wraps right now (April). The general cycle for earwigs is they overwinter as adults, lay eggs, eggs hatch and nymphs mature, then right about now they move up into the trees. Earwigs can clearly damage young tree flush. We are screening pesticides to develop a treatment program for young trees. We are also going to study how much damage they do to fruit in mature trees and how much they act as predators of pests. They may be as much of a benefit as a pest. More on this subject later.
Dr. Tracy Kahn (left) from the Department of Botany and Plant Sciences at UC Riverside leads tours...
Tracy Kahn and Cindy Fake (UCCE Placer) examine a chimera on a navel orange
The Häagen-Dazs Honey Bee Haven is not only a haven for honey bees; it's a haven for bumble bees...
Yellow-faced bumble bee (Bombus vosnesenskii) foraging in Bee Bliss salvia. (Photo by Kathy Keatley Garvey)
Yellow-faced bumble bee (Bombus vosnesenskii) peers at a visitor in the Haagen-Dazs Honey Bee Haven. (Photo by Kathy Keatley Garvey)
UC researchers are experimenting with a variety of methods that will help farmers reduce the cost of fruit thinning. Peach, nectarine, plum and apple trees typically set a tremendous amount of fruit. The fruit must be thinned considerably to ensure adequate fruit size.
Since employing farmworkers for hand thinning is a major expense for farmers, researchers have been looking for a mechanical alternative.
One such machine being tested this spring is a “drum shaker,” which was recently shipped to the Kearney Agricultural Research and Extension Center from the USDA Agricultural Research Service’s Appalachian Fruit Research Station in West Virginia.
“We took the drum shaker out to several orchards,” said UC staff research associate Becky Phene, who works in collaboration with UC pomology specialist Scott Johnson. “In four locations, we tagged and labeled shoots, then ran the drum shaker through those rows.”
The researchers counted the fruit on the shoots before and after the drum shaker treatment.
“Our findings show a modest removal of fruit at 350 to 400 rpm,” Phene said.
The experiments have shown that a number of factors come into play when using the mechanical thinning device, such as tree structure, age and fruit size.
“The larger, sturdier scaffolds are harder to shake and suffer more shoot damage or shoot removal,” she said. “The younger, more flexible scaffolds appear more capable of reverberating the energy out to more shoots and shake off more fruit. Also, larger fruit tend to have a better removal rate.”