MANATEE -- Greening is seriously threatening to cut back the citrus industry in Manatee County, where 24,247 acres are devoted to more than 3.1 million commercial citrus trees.
Now Manatee ranks 10th in Florida for citrus acreage, but "short term you're going to see a contraction in the industry," predicts Steve Futch, citrus multi-county agent for the University of Florida.
Greening, a bacterial disease spread by an insect called the citrus psyllid, feeds on a sick tree then spreads to a healthy tree. The disease -- one of the more serious affecting citrus -- causes the fruit to turn bitter, then drop unripe from the trees. The bacteria clogs the veins of the tree, making it nearly impossible for nutrients to be transported to the leaves and fruit, explained Jim Skinner, a UF agricultural gradu
ate and grandson of former Midway Groves founder, who sold the farm to operate Backyard Citrus Care in Manatee-Sarasota.
"Symptoms are an irregular blotchy mottling of the leaves, and fruit will be very small, lopsided and unpalatable. There is no cure, but through an enhanced nutritional program -- more nutrients through the leaves in sprays as well as granular fertilizer on the ground -- we can usually improve a tree," said, whose business deals with treating citrus and plants.
"The ongoing back story is the enormous amount of work and research that's occurring in how to fix the current trees with the disease," said Mac Carraway, president of Schroeder-Manatee Farms, Manatee County's largest citrus producer.
"If we can't sustain these threats and the industry, that's a threat to the economy of Florida, especially if we can't protect the existing growth as we are developing cultivated varieties," Carraway said.
In this situation, the usually competitive citrus industry is sharing information and funding research.
"It's an existential threat to the industry," said Carraway. "We are fairly effective on our own, so working together we can increase the effectiveness of our effort."
At Mixon Fruit Farms, where sales are direct to the customer, who is encouraged to come into the store and the on-site grove, the focus is on fresh fruit rather than juice. That means the consumer will be judging their fruit on looks and feel, not just quality and taste.
"We've seen greening here for the first time and it affects the production of the trees. The quality is marginal as far as the fresh fruit industry," said Dean Mixon, whose family has owned the groves for 75 years. Shipping to out-of-state customers also requires top quality produce, so misshapen or off-color fruit fail to meet the standards.
What was once a thriving agricultural business has been reinvented to more of a visitors' attraction complete with wedding gazebo and wildlife tours. "We still farm 50 acres around the packing house and we get a lot of fruit out in East Manatee," Mixon said.
"We grow it all for fresh. One of the reason we got rid of our acreage is that it got harder and harder to work it. We have three schools on three sides of our property and a trailer park on the other side," Mixon said. "People tend to forget who was here first. We have to do all our spraying after midnight when you can't see as well and you can't make sure you got good coverage. You don't usually have wind drift so that's the primary reason because if you get a spray drift you don't want it to get on people's cars."
Spraying is the only treatment for greening, although studies at UF are focusing on forms of genetic mutation that could transform existing trees to be disease resistant.
"We've sold off 250 acres to metro development, but that was before the greening. Another disease took a lot of it. If you look at our grove now, we don't have any trees to speak of that are older trees," Mixon said. "The problem with greening is that it affects younger trees. Trees 6 years old and younger seem to be where the greening really comes on them."
Pointing to the number of smaller area citrus farms that have closed down during his lifetime, Mixon said, "It's pretty equal as far as the cost of material and the operating equipment, but unless you have a big enough piece of property, it just doesn't make sense any more."
For infected trees, there is no line of defense against greening.
"Once a tree has it, it has it forever. There is no cure," Carraway said. "The key for all of us is to manage the Asian citrus psyllid insect that is the carrier. We collaborate in these regions around the state to make sure that we're coordinated as to timing and materials, and that we're doing this thing so that we're not just pushing these populations around."
Spraying adds nutrients to a tree that is hungry, Carraway explained.
"It wants to decrease production, the flush and foliage wants to decrease and be off-color and the amount of fruit wants to be less," Carraway said. "Thanks to some heroic efforts by UF, and by the industry itself in terms of access to innovation on various farms in collaboration with the academic and research work that's going on, we have quite a few ways to deliver nutrients to the trees."
Weather events, however, exaggerate the effects of greening.
"We have to alter our effectiveness in treating it, so we end up having to irrigate more to help promote circulation in these trees," Carraway said. "The tree is essentially a pump. It is taking nutrients from the ground, and the water, and it is delivering it to the fruit and that's what enables the chemistry to be what it is.
"Ultimately, that's the task: If we can continue to create what consumers and, in our case, what the processors are looking for in terms of fruit chemistry," he added. "It's imperfect, but we're much further down the road than we were in the early days of greening."
Dee Graham, Herald reporter, can be reached at 941-78-0411, ext. 7027, or tweet @DeeGrahamBH.