by Pat Williams | Sep 9, 2021
As homeowners, we do value our trees and no one wants to lose a shade tree especially on the house’s south side in Florida. On a recent site visit, a hickory tree had multiple concerns. Upon closer inspection, the tree had a bacterial infection about 30” off the ground with a smelly, black-brown ooze seeping forth. The leaf canopy was riddled with beetle holes and leaf margins were chewed by caterpillars. When leaves were viewed under the microscope, thrips (insects) and spider mites were found running around. The biggest homeowner cosmetic concern arose from hickory anthracnose (fungus) and upon closer inspection found the leaves to have hickory midge fly galls. The obvious question is should the tree come down? I’ll have you read the whole article before giving you the answer.
Each hickory gall is approximately 3/16″ wide.
Hickory anthracnose or leaf spot as seen in the banner photo is caused by a fungal infection during the wet summer months in Florida. The homeowner can usually recognize the disease by the large reddish brown spots on the upper leaf surface (sending a sample to the NFREC Plant Pathology Lab will confirm the diagnosis) and brownish spots with no formal shape on the bottom. Be sure to rake and remove all leaves to prevent your disease from overwintering close to the tree thus reducing infection next year.
A hickory gall has been cut in half to show the leaf tissue.
The fungus can be lessened by good cultural practices and appropriate fungicidal applications. Please remember it is best left to professionals when spraying a large tree. This alone is not cause to remove your tree.
Hickory gall is caused by the hickory midge fly, an insect that lays eggs in the leaf tissue. The plant responds by building up tissue around each egg almost like the oyster when forming a pearl.
As the gall tissue grows, eggs hatch and larva start to feed on this tissue. The larva will continue to
The larva has eaten all soft material inside the gall and is ready to pupate.
feed until it is ready to pupate within the gall. After forming a pupa, the midge fly will eventually emerge as an adult and females will continue to lay eggs on other leaves. The galls are more of a cosmetic damage and because your hickory leaves will fall from the tree as winter comes, the galls will normally not cause enough damage to worry about each year. Once again good cultural practices and disposal of each year’s leaves will reduce the gall numbers next year.
In a large tree with many leaves, foliar feeding by beetles and caterpillars do cause damage though the leaves will still produce enough food (photosynthesis) to keep the tree alive. Most of us never climb our trees to look at leaves to see the small insects/mites and there are more than enough leaves to maintain tree health.
The biggest concern during my site visit was their tree’s bacterial infection. A knife blade was pushed into the wound area and went in less than 1/4″. The homeowner was instructed to look at bactericide applications. In the end, this hickory tree with so many problems is still shading the home and helping cool the house. It is still giving refuge to wildlife and beneficial insects. When in doubt give our trees the benefit and keep them in place. Remember your local Extension agent is set up to make site visits and saving a tree is time well spent.
by Pat Williams | Aug 11, 2021
The lawn is a source of pride for most and anything out of the ordinary causes alarm. Now image finding something that looks like lumpy green jelly in your turfgrass and it doesn’t go away. You try raking it, spraying it, covering it, and it still comes back time and time again. One of the things we see in late spring/early summer turf is a reemergence of cyanobacteria (Nostoc), sometimes confused with algae because of green coloring and this remains all summer long.
Dehydrated cyanobacteria in a centipedegrass lawn.
Unlike normal bacteria that needs a food source, cyanobacteria contains chlorophyll and produces its own food source through photosynthesis which allows it to grow on bare sandy soils, fabric mats, concrete sidewalks, plastic, and yes even your lawn. Besides the green pigment, it also produces a blue pigment and is why we call it cyanobacteria which means blue-green bacteria. In addition to photosynthesis, cyanobacteria can also fix nitrogen, and are believed to produce cyanotoxins and allelopathic compounds which can affect plant growth around them.
Cyanobacteria are considered one of earth’s oldest organism and they have tremendous survival capabilities. They can dry out completely, be flat, flaky, black-green dried particles in your lawn and once rehydrated, spring back to life. If you happen to notice it spreading throughout your yard, remember that pieces of the organism can stick to your wet shoes or lawnmower tires and be transported unintentionally.
The question then becomes how to control the cyanobacteria and reclaim your turfgrass. The first solution is to have a healthy lawn. Cyanobacteria likes poorly-drained compacted soils. This same condition is unfavorable to turf growth and why you end up with bare spots and establishment. Reduce soil compaction by using a core aerator, and then adding organic matter. This will increase drainage, gas exchange, and encourage microorganism populations which I like to call soil pets. Spike aerators only push the soil particles aside and don’t really loosen as well. Try to reduce low lying areas in the lawn where water sits after rainfall and irrigation. You might have to till and reestablish those areas of the yard.
The same cyanobacteria pictured above 24 hours after being rehydrated in a petri dish of standing water.
Controlling the amount of water Mother Nature gives us and humidity levels during summer is not possible, but you can control your irrigation whether it be automatic (sprinkler system) or hand-watered. During the rainy season, you should be able to get by with only rainfall and shut off your system. If needed during extended dry weeks, it is easy enough to turn the system back on. It is thought that cyanobacteria likes phosphorus which is another reason to use little to no phosphorus in your lawn fertilizers.
As you begin to rid your lawn of cyanobacteria, remember when fully hydrated it forms a slippery surface so be careful walking on it. Cultural practices will be more effective in controlling the spread versus using chemical methods. Cultural solutions are safer for your lawn, yard and all of the wildlife that visits. If you need help with your cyanobacteria, please contact your local Extension office and we are always happy to assist.
A special thanks to Dr. Bryan Unruh, UF/IFAS for his assistance in identifying the cyanobacteria.
For additional information, please read the sources listed below.
Biology and Management of Nostoc (Cyanobacteria) in Nurseries and Greenhouses. H. Dail Laughinghouse IV, David E. Berthold, Chris Marble, and Debalina Saha
Rain, Overwatering Can Cause Slippery Algae to Pop Up in Turfgrass. C. Waltz
Nostoc. N.J. Franklin
by Ashley Stonecipher | Aug 5, 2021
Native Gaillardia. Photo courtesy UF/IFAS.
The hottest days of the summer are here and you might be thinking, “There is no way something could survive this heat!”. You might also be wondering “What can I do in my landscape?” Well, you are correct – it is hot and there are not many plants that thrive in this type of weather, but the good news is we are at the end of the summer season and there are things we can begin to do to get ready for fall. It’s not too late to get the last of the summer vegetables going such as lima beans, cucumbers, eggplants, and peppers. Many cool season crops can also be planted by seed now and tomatoes will thrive going into the fall season. See Vegetable Gardening in Florida
There are some heat-tolerant annuals like vinca, gaillardia, bulbine, and coleus that can be planted now in the landscape. See Annuals. Any time of the year, even late summer, bulbs like Aztec Lily, Butterfly Lily, Walking Iris, and Spider Lily can be planted. See Bulbs for Florida. Not many herbs do well in our Florida sun this time of year, but Bay Laurel, Ginger, Mexican Tarragon, and Rosemary can be planted as transplants now but not as seeds just yet. See Herbs.
August and late summer is the time of year that you may be seeing damage in your lawns. This could be caused by insects, disease, or irrigation failure. It is important to determine the cause, so the proper remedy is used. Some ways to avoid lawn damage are checking your mower blades regularly and making sure they are sharp. Also only cut the top one third of the blade of grass to not stress it in the heat of the day. It is good practice to test your irrigation clock and have a rain sensor. Some municipalities in north Florida prohibit the application of fertilizer during the summer rainy season from June to September so check with your local extension office. See Insect Management in Your Florida Lawn
You can become more self-sufficient by growing your own healthy food in your backyard. Photo by Molly Jameson.
There are some other maintenance measures you can take in August to help your landscape and prepare for the fall season. If older palm fronds are yellowing, this could indicate a deficiency in magnesium or potassium. Talk to your local agent or visit your local store for an appropriate palm fertilizer. See Palm Nutrition and Fertilization. Are you holding on to those beautiful fall mums or decorative Christmas poinsettias? Now is the time to pinch them back to allow time for buds to set for winter blooms. Finally, it is a good time to deadhead (remove old blooms) and fertilize flowering annuals and perennials. We’ve had substantial rain this summer, so keep in mind that the soil could be lacking nutrients. A soil test can give you data that indicates what you need for the up-and-coming growing season.
Information for this article can be found in the UF/IFAS EDIS publication: “North Florida Gardening Calendar” by Sydney Park Brown: ENH1190/EP451: North Florida Gardening Calendar (ufl.edu)
by Pat Williams | Jul 1, 2021
We work very hard to maintain our gardens and then we look up and vines are growing 20′ into the trees. I get asked frequently “what is growing up my trees?” My first answer is “probably the same things growing on your fences.” These include Smilax species, commonly called catbrier or greenbrier, Vitis rotundifolia, referred to as wild muscadine grape, Parthenocissus quinquefolia or Virginia Creeper, and the one to be most careful with, Toxicodendron radicans, known by many as Poison Ivy.
Spring growth on the Smilax vine.
Smilax is a native vine that grows quickly in spring and all summer. There are 12 species in Florida and 9 species commonly found in the Panhandle. Besides being armed with thorns on their stems and some leaves, Smilax spreads by underground stems called rhizomes. If you choose to ignore it, some species can cover your trees and the stems become woody and hard to remove. This vine also produces fruit and seeds are dispersed by birds all while the underground rhizomes are spreading under your lawns and gardens.
Smilax can quickly cover a tree trunk.
Removal can be difficult and mowing the vines only encourages more growth. When trying to remove by hand, wear heavy leather gloves and some eye protection because of the thorns. Cut the stems about three feet above the ground which allows you some stem to pull on to bring it out of your tree. You also then have a handle to pull and try to remove some of the rhizome from underground. Digging rhizomes is time consuming, but gives you piece of mind that they won’t come back immediately. Our family actually harvests the new shoots in spring and we use them like asparagus.
Wild muscadine grape is also native and difficult to remove. Most of the vines in nature are male and only produce by runners along the ground and then grow upwards. The female vine can produce 4-10 grapes in a cluster and then reseeds itself.
Wild muscadine grape covering a fence.
Wild grape completely covers plants and eventually the plants underneath can die. There are no thorns to contend with when removing wild grape, it is just time consuming, especially if it has taken over your fence or natural areas.
Virginia Creeper is a native vine, still considered a nursery plant in some areas of the country, and has bright red fall color.
Virginia Creeper climbing a tree trunk.
It is most often confused with poison ivy because of having five leaflets per leaf whereas poison ivy only has three leaflets per leaf. It spreads by seeds, runs along the ground, and is the easiest of these four vines to remove from your property.
Poison Ivy is a native vine distinguished by its three leaflets with the individual leaflets getting up to 6″ long. This vine spreads by seeds and underground rhizomes. What makes removal of this vine difficult is the urushiol oils which causes the skin rashes and blistering.
Poison ivy covering a tree trunk.
Care must be taken to cover up all skin and I recommend wearing waterproof clothes versus cotton which can absorb the oils and transfer them to your skin. Under no circumstances should these vines be put on the burn pile, the oils can become airborne and then you can inhale them.
Here are a few helpful tips when battling these native vines. First have patience and be dedicated, this removal will not happen over night. It may take a year or two to rid your property of the original vines. Be diligent though, because birds will continually land in your trees and deposit more seeds to get a fresh start. Try to remove vines when they are young and just beginning to climb your trees and fences. If you know you don’t have the time or energy to remove the vines from all your trees, at least cut the vines close to the ground to reduce flowering and new seeds. Be careful with poison ivy because falling leaves still contain oils. Once the vines start to have a new flush of growth, spray a non-selective herbicide on new growth and you should have good results. Lastly, remember one person can make a difference in trying to reduce the number of nuisance vines in our communities.
Here are some sited references to help with your removal tasks. Key to Nine Common Smilax Species of Florida. https://edis.ifas.ufl.edu/publication/fr375. Smilax is a Vine that can be Difficult to Control. http://blogs.ifas.ufl.edu/wakullaco/2017/04/21/smilax-is-a-vine-that-can-be-difficult-to-control/. The Muscadine Grape (Vitus rotundifolia Michx.) https://edis.ifas.ufl.edu/publication/hs100. Muscadine Grape Vines: Difficult to Control in Your Landscape. http://blogs.ifas.ufl.edu/wakullaco/2017/03/24/muscadine-grape-vines-difficult-to-control-in-your-landscape/. Parthenocissus quinquefolia: Virginia Creeper https://edis.ifas.ufl.edu/publication/fp454. Identification of Poison Ivy, Poison Oak, Poison Sumac, and Poisonwood. https://edis.ifas.ufl.edu/publication/EP220.
by Pat Williams | May 27, 2021
Our Gardening in the Panhandle blogs cover many horticultural topics concerning yards, however let us not forget about properties that contain a body of water (pond, lake, retention or detention basin, stream, river or Gulf of Mexico). Out of the nine Florida-Friendly Landscaping™ principles, five directly deal with water quality. Those principles are #2 Water Efficiently, #3 Fertilize Appropriately, #6 Manage Yard Pests Responsibly, #8 Prevent Stormwater Runoff, and #9 Protect the Waterfront. An easy argument can be made that the remaining four principles (#1 Right Plant, Right Place, #4 Mulch, #5 Attract Wildlife, and #7 Recycle) can also impact water quality on your properties.
Photo Credit: University of Florida/IFAS Extension
The quickest and easiest way to start improving water quality is setting up a maintenance-free zone along your shore. At minimum, you should keep all chemicals 10′ away from the water’s edge and increase that distance as your slope becomes steeper. Chemicals include all fertilizers (#3) and any pesticides/herbicides (#6) meant for the landscape (there are times when situations arise where treatment of the water is warranted). If you must fertilize up slope, make sure to reduce irrigation (#2) to about 25% of normal the first time which keeps the fertilizer from dissolving and running down your slope’s surface (#9).
Cascades Park in Tallahassee, FL.
If possible replace turfgrass with a no mow zone containing plants adapted for shorelines to prevent applications of fertilizer and chemicals. Plants (#1) other than turfgrass will have deeper roots, stabilize the bank better and absorb more chemicals before entering the water. These taller plants in turn can become habitats (#5) for birds and other specimens which can increase your ecosystem’s biodiversity. Some properties have collection swales or low lying areas where water pools and then flows into the water. It is best to understand how water flows through the property and reduce chemicals in those areas too (#8).
Heavy rains caused water levels to raise around this pond and decomposing leaf litter added a film over the pond.
As gardeners, we tend to compost our leaves and yard debris (#7) plus use mulch (#4) to reduce water loss from our soils. Keep mulches and compost piles away from flood zones and when possible keep leaves from washing into your water as they can create films on the surface. Never allow grass clippings to land on water surfaces as they will add nutrients when tissue decays.
As Florida continues to grow, we all must play an important role in keeping our water clean and safe for us, animals, birds, and aquatic life. If you have questions on improving your water quality, please contact your local county Extension Agent or Water Regional Specialized Agent (RSA). For additional information visit these other sites.
Protecting Florida’s Water Resources: https://gardeningsolutions.ifas.ufl.edu/care/florida-friendly-landscapes/floridas-water-resources.html
Living on Water’s Edge: http://www.sarasota.wateratlas.usf.edu/upload/documents/LivingontheWatersEdgeFreshwater.pdf
Urban Fertilizer Ordinances in the Context of Environmental Horticulture and Water Quality Extension Programs: Frequently Asked Questions: https://edis.ifas.ufl.edu/publication/AE534
