By Clint Thompson
Citrus growers in North Florida and South Georgia are expected to start harvesting in early November. While the crop still looks promising, producers need to keep an eye on rust mites, says grower Kim Jones.
“Rust mites can still be a real danger at this point. With fresh fruit, we’ve got to have a pretty piece of fruit. That rust mite can really wear us out this time of year,” said Jones, who owns a citrus packing facility in Monticello, Florida, and is part-owner of a similar facility in Tifton, Georgia.
Rust mites are exacerbated when growers apply copper fungicides. Jones saw firsthand the damage that rust mites can inflict if they are allowed to flare up.
“If you put out copper, you’re almost very likely going to have rust mites. Copper is a real good fungicide, but it enables the rust mite to grab a good strong hold,” Jones said. “It happened to us two weeks ago. We had to jump in right behind there and go after them.”
According to the University of Florida Institute of Food and Agricultural Sciences, when rust mite symptoms show on fruit before maturity, epidermal cells are destroyed. This leads to smaller fruit. These destroyed epidermal cells fracture as the fruit enlarges, causing a rough form of russeting known as sharkskin.
Damage to mature fruit creates a brown stain, leading to a polished look, known as bronzing. Fruit damage by rust mites affects the appearance and reduces grade. It can also lead to reduced size, increased water loss and increased drop if infestations are severe.
Fortunately, growers have insecticides at their disposal. Precise applications are required.
“You have to be right on top of rust mites and get them quick before they damage the fruit,” Jones warns. “They’ll get on the leaves first and scratch the leaves up really bad, but right quick behind that, they’ll be on the fruit itself, causing it to turn brown. It will really not be pretty at all.”
The crop has great potential if it can survive rust mites.
“Right now, it’s going real good. Everything still looks promising,” Jones said. “We’ve still got a good crop on the trees that’s more uniform than we’ve ever seen. The age of these groves is getting older, and we’re seeing some solid, good-looking fruit. It’s a nice change to have.”