By Bill Castle, Fred Gmitter and Jude Grosser The University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) Citrus Research and Education Center (CREC) plant improvement team has long been engaged in field research to evaluate new scions and rootstocks. That effort continues and has involved trials on public and private property. While public sites are valuable, they are …
Plan Insect and Mite Management for 2022
By Lauren Diepenbrock Insect and mite management is a year-round challenge in Florida citrus. With the warm climate, pests are at the ready as soon as plant resources are available to them. With knowledge of insect and mite biology in relation to tree phenology, plans to protect fruit and maintain productive citrus trees can be developed. MAJOR PESTSPopulations of some …
Prepare to Get Ahead of Algal Spot
By Megan Dewdney Last summer, I received many calls about algal spot, especially in late June to early July. Algal spot is a disease, caused by the algae Cephaleuros virescens, that occurs mostly on citrus tree limbs. Much of the year it is difficult to see because it is a gray-green color that blends into the color of citrus bark. …
Paraquat Alternatives for Citrus Weed Control
By Ramdas Kanissery Paraquat is an herbicide labeled for various crops, including citrus, for post-emergent weed control. When applied during the early growth stage, paraquat controls many annual grasses and broadleaf weeds commonly found in Florida citrus. Additionally, paraquat typically offers relatively good crop safety in citrus due to its lack of translocation in the plant. This makes it the …
Freeze Damage: Preparation and Recovery
By Amir Rezazadeh Low temperatures can cause serious injury to leaf, wood and fruits of citrus trees. An extended freeze can kill a citrus tree. A rapid temperature decrease or a longer duration of freezing temperature can worsen the damage. Because preparation is paramount in protecting citrus trees, growers should use the Florida Automated Weather Network. The network provides information …
Recommended Citrus Reading
By Ruth Borger The week between Christmas and New Year’s is a great time to think about reading, or rereading, a book about Florida citrus or trying out a tasty recipe featuring our favorite fruit. Here are some suggestions that might make it onto your bedside reading table for the new year. Oranges by John McPhee,1966, is considered a classic …
Now Is the Time for Dormant Season Sprays
By Lauren Diepenbrock Pest management is an ongoing effort in Florida citrus. Taking advantage of pest life cycles, whether they are tied to the season or plant phenology, can make management efforts have greater impacts on pest populations. For many citrus growers, managing impacts of Asian citrus psyllid (ACP), the vector of huanglongbing (HLB), is part of the annual management …
Get the CEUs You Need
By Ajia Paolillo If you are a certified applicator in Florida, meaning you hold a restricted-use pesticide (RUP) license, chances are you will use continuing education units (CEUs) for the renewal of your license. With the new year approaching, this is a great time to review the CEUs that you have earned toward your license and identify how many more …
Know the Signs of Freeze Damage
By Amir Rezazadeh It is important to know how cold temperatures impact citrus trees. Citrus trees are native to subtropical and tropical regions. Although some mandarins and tangerines are quite cold-hardy, other citrus trees are not particularly cold-hardy and temperatures below 20 degrees for more than four hours may kill most citrus trees. Chilling damage in citrus depends on several factors. …
Which Rootstock to Select
Valencia trees on high-vigor (left) and low-vigor (right) inducing rootstocks in a Central Ridge field trial. Note the higher yield efficiency of the smaller trees on the right and the leaning of these trees due to Hurricane Irma. By Ute Albrecht Rootstock selection is critical for longevity and productivity of a grove. The decision should be based on compatibility with …
Keeping Food Contact Surfaces Safe
By Matt Krug, Michelle Danyluk and Taylor O’Bannon Basic cleaning and sanitizing steps implemented on food contact surfaces are fundamental for reducing the risk of cross-contamination of foodborne pathogens during citrus harvest and post-harvest. While these steps may seem straightforward, several variables can influence effective implementation. A regular review of practices can ensure your operation is set up for success. …
Lebbeck Mealybug Sanitation Strategies
Lebbeck mealybug was first found causing damage in Florida citrus in Highlands County in 2019. As of this writing, it has now been found on citrus in 14 counties in Florida. This pest likely gains some dispersal assistance from wind events, either being blown on infested plant material or as crawlers on wind currents as has been noted for scale …
Be Prepared for Winter Weather
By Chris Oswalt The weather folks are predicting weak to moderate La Niña conditions this winter. Typically, having either the La Niña or El Niño conditions during the winter in Florida is a good thing. There is a historically lower probability of having severe freezing temperatures during either of these El Niño-Southern Oscillation (ENSO) conditions in Florida. What this means …
Stay Aware of Citrus Leprosis Symptoms
By Amit Levy Citrus leprosis is an exotic viral disease not currently present in Florida citrus, although the virus is present in non-citrus hosts. This disease was reported in citrus in Florida and Brazil in the early 1900s, where it caused great crop and tree losses, but was eliminated from Florida in the early 1960s. In recent years, the disease …
An Improved Method of Nutrient Analysis
By Yiannis Ampatzidis and Ute Albrecht Optimizing nutrition is important for tree health and productivity and can improve tolerance to stresses and diseases. Good nutrient management requires regular field monitoring to identify problems and examine crop responses. Leaves need to be collected and sent to a specialized laboratory for detailed information on macronutrients and micronutrients, which is time-consuming and costly. …
Stay Vigilant on Handwashing and Hygiene
By Taylor O’Bannon, Michelle Danyluk and Matt Krug If you visited any public building or restroom during the COVID-19 pandemic, you may have noticed an increased focus on handwashing and hygiene principles reflected in an abundance of signage on doors and in hallways. While it is great that public awareness has increased in the last 18 months, these have always …
Stay Prepared Throughout Hurricane Season
By Ajia Paolillo Although October is toward the end of hurricane season, which runs from June 1 to Nov. 30, it can still be a very active month for storms. These storms can range from tropical depressions to hurricanes. Major concerns for citrus growers during a storm include personnel safety, damage to trees, fruit loss and damage to equipment and …
Gibberellic Acid Use: Considerations and Concerns
By Tripti Vashisth Gibberellic acid (GA) is a naturally occurring plant hormone. GA has been used in citrus production for years to improve fruit set and size, reduce preharvest drop and delay harvest. Recent findings show that monthly foliar application of GA from September to January can improve productivity of HLB-affected Valencia trees. On average, a 30% increase in yield …
Florida Break-Even Yields and Prices
By Ariel Singerman For processed oranges grown in Southwest Florida during 2020–21, the estimated cultural costs were $1,508 per acre. Total costs of production were $1,882 per acre. Those estimates are down $214 per acre compared to the previous season. This is the result of growers reducing costs across all grove programs, except for fungicides and irrigation. Such a cutback …
Citrus Leafminer Control: Timing Is Everything
By Lukasz Stelinski The citrus leafminer (CLM) remains a major pest of citrus throughout Florida. The adults are small, white/silver colored moths about half the size of a typical mosquito (Figure 1). Adults are difficult to spot because of their small size and because they are active only in the evening (dusk) and early pre-dawn hours. CLM adults can be …