By Ramdas Kanissery Tackling herbicide tolerance in weeds is a critical aspect of effective weed control in citrus groves. It helps prevent both current and future weed management challenges. Herbicide tolerance occurs when certain weed species naturally survive and reproduce after herbicide treatment. Unlike herbicide resistance, where genetic changes allow weeds to survive and spread, herbicide tolerance doesn’t involve any …
Assessing Tools for Citrus Soil Health
Soil microbiologist Sarah Strauss on Jan. 28 discussed the benefits, challenges and unknowns of cover crops, compost and humic acid for citrus soil health. Strauss is a University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) associate professor at the Southwest Florida Research and Education Center. She pointed out that Florida’s citrus soils are problematic because they are 98% …
Plan Your 2025 Pest Management
By Lauren Diepenbrock Pest 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 invertebrate biology in relation to tree phenology, growers can develop plans to protect fruit and maintain productive citrus trees. HIGHLY PROBLEMATIC PESTS Populations of some highly problematic …
Improve the Success of Spot Sprays
By Ramdas Kanissery Spot application of post-emergent herbicides provides an effective solution for controlling weeds that are missed by standard maintenance herbicide programs in citrus groves (Figure 1, left). This method is also helpful for targeting weeds in areas that herbicide boom sprayers can’t reach, like those growing near the trees (Figure 1, right). Here are some key tips to …
Pesticides and the Environment
By Mongi Zekri Editor’s note: This article grants one continuing education unit (CEU) in the Core category toward the renewal of a Florida Department of Agriculture and Consumer Services restricted-use pesticide license when the accompanying test is submitted and approved. The fate processes for pesticides fall into three major types: adsorption, transfer and degradation. PESTICIDE ADSORPTION The adsorption process binds …
Cold-Hardy Citrus Concerns Prior to Harvest
Cold-hardy citrus growers are on the cusp of starting another harvest season. Management options need to continue up until the first crops are plucked from the trees, according to Certified Crop Adviser Bill Barber with Ag Services LLC. Barber spoke at a citrus workshop on Sept. 24 at the University of Florida Institute of Food and Agricultural Sciences Extension office …
Transforming Organic Citrus Production
Organic citrus growing presents unique hurdles in Florida, Texas and other southern states. Poor soil quality, nutrient deficiencies and a limited range of pest control options plague organic production. But the University of Florida Institute of Food and Agricultural Sciences’ (UF/IFAS) Davie Kadyampakeni is poised to transform the future of organic citrus growing. He aims to do that with a …
Management of the Invasive Peanut Snail in Citrus
Two University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researchers and an Extension agent authored an article in the Cold Hardy Citrus Connection about the invasive peanut snail in citrus. The authors are Xavier Martini, associate professor of entomology; Issac Esquivel, assistant professor of entomology; and Extension agent Danielle Williams. Excerpts follow. Bulimulus bonariensis (also known as Bulimulus …
Using Herbicides in Hot Weather
By Ramdas Kanissery Managing weeds during the summer is crucial for Florida citrus. However, due to the high temperatures typical of Florida’s summer months, several factors must be considered when using herbicides in citrus groves during hot weather. INCREASE EFFECTIVENESS High heat and drought stress can slow plant growth and affect how herbicides move or translocate in weeds. When temperatures …
Some Grapefruit Showing Less HLB Symptoms
A recent update of the U.S. Department of Agriculture Multi-Agency Coordination (MAC) Project evaluating multiple grapefruit varieties on different rootstocks reveals that some combinations have less HLB symptoms than others. Jackson has one of the lowest ranks for disease index across the combinations. The healthiest trees in the trial include: At least half of the blocks in the MAC trial …
Herbicide Application During Rainy Weather
By Ramdas Kanissery Finding the right time to apply post-emergent herbicides for controlling weeds in citrus groves is challenging in the summer months due to frequent rain. Rainy conditions delay grove maintenance, including herbicide spraying, while also impacting the effectiveness of the herbicides. Monitoring weather forecasts and identifying optimal conditions for herbicide applications can help achieve the best results. Below …
How to Improve Herbicide Efficiency
University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) weed scientist Ramdas Kanissery offered numerous tips and observations for improving herbicide efficiency at this spring’s Florida Citrus Growers’ Institute. They included: In addition to discussing herbicides, Kanissery reported that cover cropping, an emergent practice in Florida citrus production, may contribute to longer-term weed management in row middles. Read more …
Managing Chilli Thrips in CUPS
Chilli thrips (Scirtothrips dorsalis) has been documented in Florida since 1991. This pest has a history of impacting ornamentals, some vegetables, grapes and berry crops. Most recently, chilli thrips has affected citrus, but only in nurseries and in citrus under protective screens (CUPS). Feeding damage includes death of young flush (Figure 1), leaf damage on expanded flush that results in …
Planting Cold-Hardy Citrus in Florida
Muhmmad Shahid and Shahid Iqbal recently provided advice on planting cold-hardy citrus in Florida. Shahid is an assistant professor of horticulture/fruit physiologist, and Iqbal is a postdoctoral scholar in horticultural sciences, both at the University of Florida North Florida Research and Education Center. Edited excerpts from their article in the Cold Hardy Citrus Connection follow: BEFORE YOU PLANT Properly planting …
Covering the Basics of Summer Cover Crops
By Sarah Strauss The recent rising temperatures are a reminder that summer is approaching, and the beginning of the rainy season is a great time to start planting cover crops. If you are looking for a method to invest in your soil health, cover crops are one option. By definition, cover crops are planted to improve soil health and are …
Mexican Organic Orchards Offer Better Psyllid Control
A wider diversity of weeds and insects in organic Mexican citrus orchards compared to conventional orchards aids in control of the HLB-spreading Asian citrus psyllid (ACP/Diaphorina citri), a Mexican scientist reported recently. HLB is also known as citrus greening disease. “In the organic orchard, there are almost double the species of weeds compared to the conventional orchard,” Carlos Castillejos Cruz …
Study Analyzes the Economics of Cover Crops
In the face of HLB in Florida, a recent study delved into the economic viability of incorporating cover crops in citrus groves to enhance soil health and overall tree well-being. Shourish Chakravarty and Tara Wade wrote an article, Cost Analysis of Using Cover Crops in Citrus Production, about the study. Both authors are with the University of Florida Institute of …
How to Enhance Pre-emergent Herbicide Performance
By Ramdas Kanissery and Robert Riefer Pre-emergent herbicides, also known as residual herbicides, are highly effective in the long-term suppression of weeds in citrus tree rows. These herbicides remain in the soil and prevent susceptible weeds from germinating. In order to achieve the best weed control results, pre-emergent herbicides need to stay within approximately the top 5 inches of soil, …
Brassinosteroid and Weed Management Research Updated
Brassinosteroids for HLB-infected trees and the latest on year-round weed management were discussed at a Jan. 17 OJ Break at the Citrus Research and Education Center in Lake Alfred, Florida. University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) multi-county citrus Extension agent Chris Oswalt hosted the event. UF/IFAS assistant professors Fernando Alferez and Ramdas Kanissery made the presentations …
Groups Call for Glyphosate Ban
The Center for Food Safety on Dec. 13 petitioned the U.S. Environmental Protection Agency (EPA) to immediately suspend and cancel the herbicide glyphosate, the main ingredient in Monsanto’s Roundup. The center filed the petition on behalf of itself, Beyond Pesticides and four farmworker advocacy groups. Last year, in a lawsuit by the same nonprofit organizations, a federal court of appeals struck down …





























