by Gary Knox | Jun 29, 2017
IPM for Shrubs in Southeastern US Nursery Production Volume II is the third book released by the Southern Nursery Integrated Pest Management Working Group (SNIPM) and includes chapters on hydrangea, loropetalum, holly, rhododendron (including azalea), Indian hawthorn, and weed management. Each chapter covers history, culture and management of the major species and cultivars in production, as well as arthropod pest management and disease management. Within the discussion of these topics, each chapter includes strategies for developing effective IPM programs for key pests and plant pathogens, including tables of fungicides and insecticides for use with these key organisms. While developed for nursery producers, this information also may be useful to landscapers, students, arborists and others.
This free book is downloadable as pdf chapters at
http://wiki.bugwood.org/IPM_Shrub_Book_II.
The first book, IPM of Select Deciduous Trees in Southeastern U.S. Nursery Production, was released in May 2012 and is available for free download as chapter .pdf files at http://wiki.bugwood.org/SNIPM and as an eBook from the iTunes Bookstore https://itunes.apple.com/us/book/ipm-for-select-deciduous-trees/id541182125?mt=11.
The second book, IPM for Shrubs in Southeastern US Nursery Production Volume I, was released in June 2014 and can also be downloaded as chapter .pdf files at http://wiki.bugwood.org/SNIPM or from the iTunes Bookstore at https://itunes.apple.com/us/book/ipm-for-shrubs-in-southeastern/id903114207?mt=11.
The SNIPM Working Group is a multi-disciplinary group of Extension professionals formed to more efficiently and effectively develop and deliver educational programming to the southern U.S. nursery and landscape industry.
by Mary Salinas | May 11, 2017
Citrus canker symptoms on twigs, leaves and fruit. Photo by Timothy Schubert, FDACS
In November 2013, citrus canker was found for the first time in the Florida panhandle in Gulf Breeze in southern Santa Rosa County. The Florida Department of Agriculture and Consumer Services (FDACS) tested and confirmed the disease on grapefruit trees in a residential landscape. Since that time, citrus canker has been confirmed on citrus trees at 27 more locations in Gulf Breeze. To my knowledge it has not been found in any other location in the panhandle. Not yet.
Citrus canker lesions on leaves are raised, rough and visible on both sides of the leaf. Photo by Timothy Shubert, FDACS.
Citrus canker is a serious bacterial disease that only infects citrus trees. It will not infect any other plant species nor is it a threat to human health. This highly contagious disease has no cure as yet. Severely affected trees experience substantial leaf and premature fruit drop and serve as a source for infecting other citrus in the area. The disease spreads through wind, rain and transportation of infected plant material from other locations.
We do not know how the disease came to infect trees in our region. The disease could have been spread through infected fruit or trees brought here from areas where the disease is established, such as central or south Florida.
What should you do if you suspect your citrus is infected with this disease?
Citrus canker lesions can appear in the mines left by the citrus leafminer pest. Photo by Timothy Schubert, FDACS
- Look at Homeowner Fact Sheet: Citrus Canker for more information.
- Leave the tree in place in your yard and call the Division of Plant Industry at FDACS at 1-888-397-1517 for a free inspection and testing of your citrus trees.
- Consult your local Horticulture Extension Agent for more information and control/removal strategies.
- Proper removal of infected trees is recommended to prevent the spread of citrus canker but is not mandatory.
For more information please see:
Save Our Citrus Website
UF IFAS Gardening Solutions: Citrus
Citrus Culture in the Home Landscape
UF IFAS Extension Online Guide to Citrus Diseases
by Matt Lollar | Mar 20, 2017
A type III fairy ring. Photo Credit: Alex Bolques, Assistant Professor, Florida A&M University
Mushrooms often are grouped in a circle in your lawn. This is due to the circular release of spores from a central mushroom. “Fairy Ring” is a term used to describe this phenomenon. Fairy rings can be caused by multiple mushroom species such as Chlorophyllum spp., Marasmius spp., Lepiota spp., Lycoperdon spp., and other basidiomycete fungi.
Occurrence
Fairy rings most commonly invade your yard during the summer months, when the Florida panhandle receives the most rain. The mushrooms cause the development and spread of the rings by the release of spores. Spores produce more mushrooms and are similar to the seed produced by plants.
Fairy Ring “Types”
Fairy rings can be seen in three forms:
- Type I rings have a zone of dead grass just inside a zone of dark green grass. Weeds often invade the dead zone.
- Type II rings have only a band of dark green turf, with or without mushrooms present in the band.
- Type III rings do not exhibit a dead zone or a dark green zone, but a ring of mushrooms is present.
The size and fill of rings varies considerably. Rings are often 6 ft or more in diameter. The fill of a ring can range from a quarter circle to a semicircle or full circle.
Cultural Controls
The rings will disappear naturally, but it could take up to five years. Although it is possible to dig up the fairy ring sites, it is a good possibility the rings will return if the food source (buried, rotting wood or other organic matter) for the fungi is still present underground.
In some situations, the fungi coat the soil particles and make the soil hydrophobic (meaning it repels water), which will result in rings of dead grass. If the soil under this dead grass is dry but the soil under healthy grass next to it is wet, then it is necessary to aerate or break up the soil under the dead grass with a pitchfork or other cultivation tool.
Rings of dead turf due to fairy ring fungi. Photo Credit: University of Florida/IFAS Extension.
Chemical Controls
Effective fungicides include products containing the active ingredients azoxystrobin, flutolanil, metconazole, pyraclostrobin, and triticonazole.
Fungicides inhibit the fungus only. They do not eliminate the dark green or dead rings of turfgrass and do not solve the dry soil problem.
A homeowner’s guide to lawn fungicides can be found at the University of Florida/IFAS Extension Electronic Data Information Source (EDIS) website (http://edis.ifas.ufl.edu/document_pp154).
by Carrie Stevenson | Mar 2, 2017
Small Fruit vs Normal
If we look at the big picture when it comes to invasive species, some of the smallest organisms on the planet should pop right into focus. A microscopic bacterium named Candidatus Liberibacter asiaticus, the cause of Citrus Greening (HLB), has devastated the citrus industry worldwide. This tiny creature lives and multiplies within the phloem tissue of susceptible plants. From the leaves to the roots, damage is caused by an interruption in the flow of food produced through photosynthesis. Infected trees show a significant reduction in root mass even before the canopy thins dramatically. The leaves eventually exhibit a blotchy, yellow mottle that usually looks different from the more symmetrical chlorotic pattern caused by soil nutrient deficiencies.
One of the primary vectors for the spread of HLB is an insect called the Asian citrus psyllid. These insects feed by sucking juices from the plant tissues and can then transfer bacteria from one tree to another. HLB has been spread through the use of infected bud wood during grafting operations also. One of the challenges with battling this invasive bacterium is that plants don’t generally show noticeable symptoms for perhaps 3 years or even longer. As you would guess, if the psyllids are present they will be spreading the disease during this time. Strategies to combat the impacts of this industry-crippling disease have involved spraying to reduce the psyllid population, actual tree removal and replacement with healthy trees, and cooperative efforts between growers in citrus producing areas. You can imagine that if you were trying to manage this issue and your neighbor grower was not, long-term effectiveness of your efforts would be much diminished. Production costs to fight citrus greening in Florida have increased by 107% over the past 10 years and 20% of the citrus producing land in the state has been abandoned for citrus.
Classic blotchy mottle in Leaves
Many scientists and citrus lovers had hopes at one time that the Florida Panhandle would be protected by our cooler climate, but HLB has now been confirmed in more than one location in backyard trees in Franklin County. The presence of an established population of psyllids has yet to be determined, as there is a possibility infected trees were brought in.
A team of plant pathologists, entomologists, and horticulturists at the University of Florida’s centers in Quincy and Lake Alfred and extension agents in the panhandle are now considering this new finding of HLB to help devise the most effective management strategies to combat this tiny invader in North Florida. With no silver-bullet-cure in sight, cooperative efforts by those affected are the best management practice for all concerned. Vigilance is also important. If you want to learn more about HLB and other invasive species contact your local UF/IFAS Extension office.
Asymmetrical Fruit
Typical nutrient deficiencies observed in leaf, on trees with heavy fruit load. Not related to Citrus Greening (HLB)
Article by: Erik Lovestrand, UF/IFAS Franklin County Extension Director/Florida Sea Grant Agent
by Blake Thaxton | Sep 29, 2016
St. Augustinegrass roots rotted due to take-all root rot. (Photo Credit: IFAS Photos)
The crisp air of fall is upon us. Maybe. We live in northwest Florida and we are not experiencing the change in weather just yet. With the change in weather coming, we are having specific issues in turfgrass lawns and are sure to have others in the near future. Extension agents in the western panhandle have come into contact with several St. Augustine lawns with symptoms and signs of take-all root rot (Gaeumannomyces graminis var. graminis) and we can soon expect with cooler temperatures for Large Patch to be rearing its ugly head.
Early aboveground symptoms of take-all root rot. (Photo Credit: IFAS Photos)
Take-all root rot is sometimes referred to as a “stress disease”, as it is brought on by stressful weather conditions and improper management. Periods of rainfall can provide conditions for the disease to affect all warm season grasses. Other stresses such as improper mowing height, improper irrigation, and improper fertilization can worsen the situation. For example, St. Augustinegrass, except dwarf cultivars, should be mowed at 3.5 to 4 inches and the mower should never remove more than 1/3 of the leaf blade at any cutting. With the current high temperatures and prolonged periods of rainfall it can be difficult to follow this practice. When a homeowner does not mow the lawn in a timely manner and lets the lawn grass get much too high and cuts more than 1/3 of the grass blade, this can become a stress to the lawn. Fungicide sprays can be made during favorable environmental conditions, before symptoms are seen to protect from infection with take-all root rot for high valued properties. To learn more about take-all root rot refer to this University of Florida/IFAS Extension publication: Take-all Root Rot
With the fall weather coming, please be sure to read and learn about large patch disease as well. This can brought on by temperatures of less than 80 degrees and high humidity or extended periods of rainfall. Read the University of Florida/IFAS Extension publication for more information: Large Patch
For any other information needed regarding proper lawn management, please visit Your Florida Lawn or contact your local UF/IFAS Extension office.
by Ray Bodrey | Aug 19, 2016
Being a gardener in the panhandle has its advantages. We’re able to grow a tremendous variety of vegetables on a year-round basis. However, in this climate, plant diseases, insects and weeds can often thrive. Usually, chemical measures are applied to thwart these pests. Some panhandle gardeners are now searching for techniques regarding a more natural form of gardening, known as organic. With fall garden planting just ahead, this may be an option for conventional vegetable gardeners looking for a challenge.
Vegetable Garden at UF/IFAS Extension Wakulla County. Photo credit: Ray Bodrey UF/IFAS.
So, what is organic gardening? Well, that really depends on who you ask. A broad definition is gardening without the use of synthesized fertilizers and industrial pesticides. Fair warning, “organic” does not translate into easier physical gardening methods. Laborious weeding and amending of soil are big parts of this gardening philosophy. This begs the question, why give up these proven industrial nutrient and pest control practices? Answer: organic gardening enthusiasts are extremely health conscious with the belief that vigorous outdoor activity coupled with food free of industrial chemicals will lead to better nutrition and health.
As stated earlier, the main difference between conventional and organic gardening is the methods used in fertilization and pest control. In either gardening style, be sure to select a garden plot with well-drained soil, as this is key for any vegetable crop. Soil preparation is the most important step in the process. To have a successful organic operation, the garden will require abundant quantities of organic material, usually in the form of animal manures and compost or mixed organic fertilizer. These materials will ensure water and nutrient holding capacity. Organic matter also supports microbiological activity in the soil. This contributes additional nutrients for plant uptake. Organic fertilizers and conditioners work very slowly. The vegetable garden soil will need to be mixed and prepped at least three weeks ahead of planting.
Effective organic pest management begins with observing the correct planting times, selection of the proper plant variety and water scheduling. Selecting vegetable varieties with pest resistant characteristics should be considered. Crop rotation is also a must. Members of the same crop family should not be planted repeatedly in the same organic garden soil. Over watering can be an issue. Avoid soils from becoming too wet and water only during daylight hours.
For weed management, using hand tools to physically removing weeds is the only control method. As for insect management, planting native plants in the immediate landscape of the organic garden will help draw in beneficial insects that will feast on garden insect pests. The use of horticultural oil or neem oil is useful. However, please read the product label. Some brands of oils are not necessarily “organic”. Nematodes, which are microscopic worms that attack plant roots, are less likely an issue in organic gardens. High levels of organic matter in soil causes an inhospitable environment for nematodes. Organic disease management unfortunately offers little to no controls. Sanitation, planting resistant varieties and crop rotation are the only defense mechanisms. Sanitation refers to avoiding the introduction of potential diseased transplants. Disinfecting gardens tools will also help. Hydrogen peroxide, chlorine and household bleach are disinfecting chemicals allowed in organic gardening settings as these chemicals are used in organic production systems for sanitation. Staking and mulching are also ways to keep plants from diseases by avoiding contact with each other and the soil.
Organic gardening can be a challenge to manage, but better health and nutrition could be the reward. Please take the article recommendations into consideration when deciding on whether to plant an organic garden. For more information, contact your local county extension office.
Supporting information for this article can be found in the UF/IFAS EDIS publication, Organic Vegetable Gardening in Florida, by Danielle D. Treadwell, Sydney Park Brown, James Stephens, and Susan Webb.
