Time for Brown Rot Management

Tacy CalliesDiseases, Tip of the Week

By Evan Johnson The Florida summer rainy season is in full swing, and there have been one or two root flushes by now. This is a good environment for increases in soil Phytophthora propagule counts. High counts have been seen this year, especially in Southwest Florida. While much of the focus may be on root rot, it is important to … Read More

What To Do About Algal Spot

Tacy CalliesDiseases, Tip of the Week

By Megan Dewdney I did not need to visit my field trial to know that algal spot was in bloom on citrus in the last month. I have received many phone calls about it recently as growers notice the bright orange doughnuts on their tree limbs. For those unfamiliar with algal spot, it is a disease that occurs mostly on … Read More

Spot and Stop Worker Heat Stress

Tacy CalliesTip of the Week, Weather

By Amir Rezazadeh Heat stress happens when the body is exposed to extreme heat in a hot environment. Heat-related illnesses include heat cramps, heat exhaustion, heat rashes or heat stroke. Other signs of heat stress include sweaty palms, fogged-up safety glasses and dizziness. Those who work outdoors or in hot environments are at risk of heat stress. Workers who are … Read More

Understanding Physiological Fruit Drop of Citrus

Tacy CalliesFruit Drop, Tip of the Week

By Tripti Vashisth, Megan Dewdney and Lauren Diepenbrock Citrus flowers profusely, but less than 2% of the flowers become harvestable fruit. In other words, 98% of the flowers seen during bloom will end up on the grove floor at some point during fruit development, whether as a flower, fruitlet, young fruit or mature fruit. Profuse flowering allows trees to produce … Read More

Psyllid Exclusion and Screen Selection

Tacy CalliesCUPS, Tip of the Week

By Arnold Schumann and Timothy Ebert As the adage goes, “necessity is the mother of invention.” Since the presence of huanglongbing (citrus greening) in Florida, new methods of managing the Asian citrus psyllid that transmits the bacteria have resulted in the growing of citrus in screen houses (CUPS, citrus under protective screen) and the use of individual protective covers (IPCs), … Read More

Inspect Your Irrigation System Regularly

Tacy CalliesIrrigation, Tip of the Week

By Ajia Paolillo Throughout the year, it is a good practice to check your irrigation system for leaks, wear, corrosion and other physical damage that can limit the efficiency of the system. Proper irrigation provides the tree with the water it needs, especially during periods of drought and during the important stages of flowering, fruit set and enlargement, and leaf … Read More

Be Prepared for Hurricane Season

Tacy Callieshurricane, Tip of the Week


By Fernando Alferez and Mongi Zekri The National Oceanic and Atmospheric Administration has predicted another above-normal Atlantic hurricane season. While hurricanes have always been a risk or danger to Florida, their threat is growing. Although experts do not anticipate the historic level of storm activity seen in 2020, it only takes one storm to severely impact and devastate citrus groves. It … Read More

Keep Current With MRLs for Exports

Tacy CalliesExport, Tip of the Week

By Mark A. Ritenour The United States and other countries set maximum residue limits (MRLs) on fresh produce for various chemicals, including pesticides that might be used before or after harvest. These materials must be labeled for use on the crop of interest and used only according to label instructions. While it is unlikely for U.S. MRLs to be exceeded … Read More

Monitoring Citrus Root Weevils

Tacy CalliesPests, Tip of the Week

By Larry Duncan Soilborne larvae that feed on citrus roots are the damaging life stage of Diaprepes abbreviatus and Pachnaeus spp. (bluegreen) root weevils. Newly developed adult weevils, which emerge throughout the warm months of the year, also occur in soil.  A peak emergence of adults occurs at some point each spring or early summer. Less frequently, a smaller emergence … Read More

Keep Citrus Trees Hydrated

Tacy CalliesIrrigation, Tip of the Week

Frequent irrigation with good quality water can improve fruit growth and development and overall productivity. By Tripti Vashisth HLB-affected citrus trees have small and weak root systems. Though the roots are efficient in taking up water and nutrients, there are not sufficient roots to support the tree’s canopy requirement. Therefore, the trees often experience water and nutrient deficit. Not all … Read More

Scouting for Lebbeck Mealybugs

Tacy CalliesPests, Tip of the Week

By Lauren Diepenbrock Lebbeck mealybugs (Nipaecoccus viridis) have quickly made an impact on citrus groves in Central and South Florida since the pest was first found in 2019. While management techniques are still being studied, this article describes actions growers can take to find this pest before it becomes a problem. SOOTY MOLDLebbeck mealybugs excrete sugary honeydew, much like many … Read More

What to Consider Before Planting Cover Crops

Tacy CalliesCover Crops, Tip of the Week

For those interested in cover crops for citrus groves, the end of harvest and the upcoming start of the rainy season is a great time to start planning. Cover crops can have a variety of benefits to soil health. These include increasing soil organic matter and microbial diversity and activity as well as reducing weed growth. While research is still … Read More

Citrus Leafminer Sampling Techniques

Tacy CalliesPests, Tip of the Week

By Xavier Martini Citrus leafminer (CLM) is a recurring pest in citrus groves that lays eggs on new growth shoots (flush). After hatching, larvae penetrate directly into the leaf and begin feeding on sap and leaving a serpentine mine in the leaf. CLM population dynamics are mostly driven by flushing pattern, with two flight peaks in early spring and late … Read More

Tackling Weeds After Composting

Tacy CalliesTip of the Week, weeds

By Ramdas Kanissery The use of compost in tree rows is receiving increasing attention among citrus growers. The use of weed-free certified products can considerably minimize the weed emergence issues associated with compost use. However, eventually, weeds will start to grow in the composted areas in the grove. As compost and similar soil amendments prove to be very rich in … Read More

Plan Greasy Spot and Melanose Management

Tacy CalliesDiseases, Tip of the Week

By Megan Dewdney Greasy spot and melanose are two fungal diseases that have long needed the attention of Florida citrus growers. While they are more of a concern for fresh fruit growers, trees for processing can be damaged, too. In terms of management priorities, greasy spot is the greater concern since it reduces tree photosynthetic capacity and causes defoliation. Melanose … Read More

Plan Now for Phytophthora Season

Tacy CalliesDiseases, Tip of the Week

By Evan Johnson The Florida citrus spring leaf flush is hardening off, which means the first root flush of the year is beginning. With the spring root flush comes thoughts of phytophthora foot rot. Spring roots are at particular risk in groves that had high phytophthora pressure last fall because many of the resting spores will start activating with the … Read More

Instant Information on Herbicides

Tacy CalliesTip of the Week, weeds

By Ramdas Kanissery Citrus growers face weed management problems throughout the year due to favorable conditions that allow the rapid growth of weeds in groves. A weed-free tree row is desired in citrus to minimize competition with the trees. This can be achieved by utilizing post-emergent herbicides that control the weeds that have already emerged. Growers have several product options … Read More

What to Do About Citrus Black Spot

Tacy CalliesDiseases, Tip of the Week

By Megan Dewdney Citrus black spot is one of the newer diseases to worry Florida citrus growers. The fungal disease was first detected in Southwest Florida in 2010. The vast majority of finds have been in the southwestern citrus-producing counties of Collier, Hardee, Lee, Charlotte and Glades, but the disease has slowly moved northward. Black spot is still considered a … Read More

Time to Check Under the Hood for Nematodes

Tacy CalliesPests, Tip of the Week

By Larry Duncan Monitoring population levels of plant parasitic nematodes and phytophthora is best done in springtime prior to the rainy season. Peak population density of the citrus nematode (Tylenchulus semipentrans) occurs at that time, and the accuracy of sample results increases with population density. The sampled population levels of this nematode and those of Phytophthora spp. can be compared … Read More

Scout for Scale and Mealybug Crawlers

Tacy CalliesPests, Tip of the Week

By Lauren Diepenbrock While scale and mealybug pests commonly found in citrus have historically been controlled by predators and parasites, management advice for this group of insects is often requested. There are likely several underlying factors to these insects becoming more frequently encountered. This includes changes in insecticide management practices, changes in nutritional management, and increased scouting due to the … Read More