Not all trees and woody species are welcome in the landscape. In fact, some woody species can be pesky and problematic and for lack of a better term “weeds”. Despite the fact that some of these species are native trees, bushes, and vines, many can be aggressive and problematic in the home landscape and urban settings. If you have ever cared for a flower bed or garden in the Panhandle, you are probably well acquainted with these and have pulled seedlings and small saplings out of beds, hedges, and seemingly any other nook and cranny of your landscape. If you cut them off using loppers or a saw you also know how aggressively they resprout and how extensive their root system can become. Vegetation grows quickly and often aggressively in our humid sub-tropical climates. If you leave an area of land vacant for very long here, it quickly becomes a thicket in no time. Some of our oaks, particularly water and laurel oaks, can be pesky and troublesome. It seems like I am constantly battling problem oaks in my home landscape, with varying degrees of success. I will pull out, cut out, and apply herbicide only to look up and see a substantial oak sapling rocketing up through azaleas or other hedges. Without fail this is a water or laurel oak nearly 100% of the time, with some other hardwood trees and shrub species thrown in occasionally.
Oak sapling overtaking shrubbery in a local landscape Escambia County, FL Photo Credit: Ian Stone
What is the best way to tackle these pesky woody “weeds” when they cause persistent problems and pop up in undesirable spaces? The answer is to either mechanically removal them or employ very careful and targeted herbicide application. As a professional forester I have spent a large part of my career controlling these brush species using a host of mechanical and herbicide control methods and very well planned prescribed fires. Obviously using large heavy machinery and prescribed fire in urban and suburban settings and landscapes is not an option but using hand tools for mechanical removal and herbicides where needed and best suited is a winning combo for the home landscape.
First you want to determine what species you are dealing with and what stage of development it is in. As I mentioned, water oak and laurel oak are usually the problem oaks we encounter and can reproduce at extremely high rates and create undesirable crowded stands of stunted oak. These species are what foresters call early successional, meaning they tend to establish in forest openings and areas impacted by a disturbance such as a hurricane or windstorm. They produce large amounts of small acorns and grow very fast and they also have poor characteristics where they are susceptible to wind throw and disease. Effectively, they reproduce heavily, grow fast, and die young; that is their natural adaptation and life cycle and what causes them to be pesky and weedy in the home landscape. We don’t realize it, but our home lawns and flower beds create the perfect early successional habitat for these oaks and other brush species such as yaupon holly, titi, wax myrtle, and others. It doesn’t stop there – in heavily shaded areas, very shade tolerant oaks, brush, and vines tend to become established. Vines such as Virginia creeper, greenbriers (Smilax spp.), pepper-vine, and others are particularly annoying as these woody species also love to grow up in fences, particularly chain link, and are difficult to remove.
So what are the best methods to handle problem woody species in the home landscape? The best option is to catch them as seedlings and young plants and pull them up by the roots and all. If you can do this, you will avoid issues with resprouting. If you have larger, more well-established brush and small trees in your landscape, you can cut them back close to the ground, but you are likely to have issues with resprouting. This can be very frustrating and can result in a persistent problem. By consistently cutting these back you may be able to exhaust the plant’s reserve, but this is unlikely. Depending on the size of the root system you may be able to dig up the roots using some elbow grease and a shovel or mattock, but if significant roots are left behind, some woody species can resprout from the remaining roots. This is when simply cutting off the main stem or other mechanical methods often are not sufficient for long term control.
When dealing with well-established woody species with a significant stem size, using a properly labeled and effective herbicide can be a big time and hassle saver. You want to use a herbicide that is labeled for hack and squirt applications and/or cut stump applications. Many brush control and tough brush herbicides are labeled this way and can be applied using these methods. Herbicides with the active ingredients of triclopyr or glyphosate are the most effective for these methods and readily available for home use. Triclopyr products are usually the most effective on tough brush and woody species. Make sure the species you are targeting is listed on the label and follow the label directions exactly for the methods and concentrations to apply the herbicide correctly.
Oak resprouting from stump after herbicide treatment. Note the deformed leaves on the regrowth showing herbicide damage. Photo Credit: Ian Stone
Cut stump and hack and squirt applications require a bit of a different method of application. Instead of spraying foliage, you apply the herbicide into fresh cuts using a squirt bottle or a paint brush. You should wear proper protective equipment when working with any herbicide and this is also listed in the label. Long sleeves and pants along with chemical resistant gloves and eye protection is usually the minimum recommended. For hack and squirt, make a series of connecting cuts in a ring around the problem stem and squirt the herbicide mixture into the fresh cuts using the squirt bottle. For cut stump treatments cut the stem(s) of the problem tree or shrub off slightly above the ground and apply the mixture using a paint brush or squirt bottle, focusing on the outer portion of the stump right next to the bark. These methods work by introducing the herbicide to the cambium layer, which is the actively growing and live tissue just under the bark in woody plants. By doing this it will travel through the tissue and kill both the roots and stems. It is very important that the cuts are fresh, and the application must be made as soon as possible after the cuts are completed. Once the brush is killed back, you can wait for the stem or stump to rot or remove it once it has completely died. This method is effective at controlling resprouting but is not 100% effective on all applications. If the woody plant in question continues to resprout, you can make fresh cuts and reapply. An advantage of this method is it can be done in winter even when the plant is dormant, as it does not rely on foliage to uptake the herbicide. That means you can use it year-round, and you can take advantage of the cooler winter weather to do this labor-intensive work.
With careful work and proper technique, these methods can be beneficial to control persistent brush problems in the home landscape. When using herbicides it is very important to be aware of off target damage to desirable plants. One of the advantages of hack and squirt and cut stump applications is that they are very targeted and minimize issues with off target damage and drift. Care should be taken not to get the herbicide mixture on the stems of desirable shrubs and trees, and they can penetrate the bark and do damage, especially on thin barked species. If you have questions about how to properly use a herbicide or reading the label contact your local extension office.
The May Gardening in the Panhandle Live focused on the various aspects of turfgrass care and species characteristics.
The panel included:
Dr. Bryan Unruh, UF IFAS Extension Turfgrass Science Professor
Sheila Dunning, UF IFAS Extension Commercial Horticulture Agent in Okaloosa County
Josh Criss, UF IFAS Extension Residential Horticulture Agent in Santa Rosa County
Daniel Leonard, UF IFAS Extension Horticulture Agent and Director in Calhoun County
Q: Does No Mow March cause more problems in maintaining a good lawn? Pay attention to what you are leaving behind. If you have aggressive perennial weeds, that could cause issues later. Also, be aware of what types of weeds. Annual wildflowers may be acceptable that will reseed next year. Mowing before seeds mature is always an option too. Remember that if there are significant weeds, they are taking advantage of a void in the turf. Find out why the turf is not growing as well and work on that issue. Improve the health of the grass to have less issues with some weeds.
Q: What is an unhealthy lawn? Grass that is not performing at a level that is normal for that turf. Not growing well, does not have appropriate color for the species, thinning out. The difficult part is figuring out why. Could be that that turf is not suited to the site, cultural practices are an issue, pest problem. We tend to manage turf too much. Take a more minimalistic approach and as needed for turf management instead of a scheduled maintenance plan.
Q: Fertilizer and pesticide inputs aside, can ornamental lawns provide environmental benefits such as carbon sequestration? Plants remove CO2 and supply O2. Turf areas can reduce temperatures, serve as erosion management and build soil. Also filtering some pollutants. Turfgrass also has huge potential to accumulate and store carbon. Turf has many recreational uses that other surfaces don’t offer and the overall aesthetics of a healthy lawn can improve value of the property.
Q: What is the best grass for Florida? You have to match the turf to an appropriate site and turfgrass may not be the best choice for a site. On an urban site, shade from trees will also dictate if turf is appropriate. The best grass for the back yard may not be the best suited for the front yard. Centipedegrass is a good selection for the case of a grass that grows well with low inputs. It will be a lighter shade of green which is its natural color. If you prefer to have inputs of fertilizer and water routinely, centipedegrass would not be the best choice. Zoysiagrass is more suited for those who desire a more magazine cover type lawn that is well manicured. A field type lawn is best with bahiagrass.
Q: Is zoysiagrass the fastest growing market for turfgrass? There are now good zoysiagrass varieties on the market and better ones coming along.
Zoysiagrass is a very drought tolerant species but it survives by going into dormancy. It survives without water by going from green to bluishgray to brown very quickly. In order to maintain a green, well manicured zoysiagrass lawn, irrigation input is needed.
Q: Can I grow a lawn from centipedegrass seed? How long will it take to fill in? It takes 3 years to establish a lawn from centipedgrass seeding. That is with minimal inputs but mowing is important in the establishment process. Dr. Unruh does not recommend seeding into patches because water needs for seed are higher than established grass. Sodding or plugging is better for patching spots.
Q: What is the best choice of grass for a partly shaded lawn/best under a large tree? Long term, you need a shade tolerant grass such as one of the St. Augustinegrasses or certain cultivars of zoysia (Palisades is one). As the tree grows over the years, grass may not remain suited for that location.
Q: What type of grass would you recommend for a meadow area that would be natural/unmowed? Bahiagrass is a good option.
Q: How do we encourage bee lawns? Centipedegrass flowers will attract some bees. Clovers (Red, white, hopclover) in the winter months through spring. Consider your space. May just be small sections or at the edge of the yard.
Q: How often should you aerate your lawn and what is the best method? Sandy soils can compact. Every other year aeration if you have traffic patterns from vehicles, play, or paths. Use a ½ tine with lots of holes back and forth over the lawn.
Q: How to maintain a healthy lawn in our hot and humid summers? Overwatering is common. Grass gives signs of needing water such as leaf blades folding in half, a color change, and grass not recovering after walking. Calibrate your system to apply ½ to ¾ inch at each time.
Q: How to measure water volume with an automatic irrigation system. In a zone, randomly place 10-15 straight edged cans that are all the same size. Run your system for a set time and see how much is in each can. You will be able to see where coverage is poor, just right, and overlapping too much. Measure with a ruler and average out the amount. Adjust your time to meet ½ to ¾ inch. Each zone is calibrated separately. Same for zoysiagrass but this grass will show you where your system is not functioning well since it’s response to drought is to go dormant. Still ½ to ¾ inch as needed.
Q: Do I have to fertilize and apply pesticides to have a healthy lawn? No. All plants need nutrition and fertilizer is just one source of nutrition. A good soil can provide sufficient levels of nutrients for the lawn. Sandy soils may need supplemental nutrients. Could be from compost incorporated in as well.
Q: My yard is a mix of grasses. Is this a problem for fertilizer and watering? You may need to fertilize differently depending on the needs of the various grasses. If a grass is growing into another, then it is favorable conditions for that grass – sunlight, mowing, water availability. You may have to manage for the one that is doing the best.
Q: Should I bag my mowing clippings for my Zoysia lawn or not? Generally the recommendation is to allow clipping to fall for a yard that is being routinely mowed. Blades will compost. The exception is with zoysia when thatch is becoming a problem or when you have neglected mowing for a period and clumps of clipping are piled on the lawn.
Q: Is weed control beneficial or harmful? Improperly used herbicides could have environmental impacts. Follow the label carefully. Manage weeds through cultural practices too.
Q: How do I get rid of crabgrass? Annual weed that germinates when soil temps reach 55 degrees F. Could be mid-January or a little later. Pre-emergent herbicides can help. Not many options for post emergent weed control. From Dr. Unruh: We do not recommend Weed and Feed products since timing is different for both. North Florida fertilizer applications should not occur before mid-April. 0-0-7 with pre-emergent would be the only exception. The 0-0-7 is just potassium.
Q: How to detect, kill and prevent ground pearls. There are no chemicals controls for ground pearls. Thinning out areas. Insects that are in the soil, with pearl stage attached to the roots. Females are hot pink and crawlers. Maybe something in the future. Try to outgrow ground pearls with faster growing grasses such as St. Augustinegrass and zoysiagrass.
Q: How do you control a heavy infestation of doveweed? Do not handpull. Annual weed that germinates later when soils reach 70 degrees F. Pre-emergent herbicides. Mow more often and manage irrigation. Improve drainage. Clean mowers too.
Q: Are there herbicides that will not harm birds? Insecticides have the biggest impact on wildlife compared to other types of pesticides. Many herbicides use a carrier that looks like a grain so water immediately according to label to move chemical off carrier. Follow the restrictions about application close to water. Read the label.
Q: Are all zoysia grasses hard to keep out of landscape beds? Establish a border with edging to block the growth. Must be buried and above grade as well.
Q: If we’ve lost most of our backyard due to killing off weeds with only some grass left, how’s the best way to start? For smaller spots, allow surrounding turf to run back into areas. Resodding areas or plugging new grass.
Q: Large sections of my front lawn died last summer and I diagnosed it as brown spot/large patch. How do I address? Why having large patch – poor drainage and fix that issue. Also zoysiagrass is susceptible to large patch. You can restablish grass but manage so conditions are not as suitable for the disease. Water as needed and nutrients only as needed.
Q: We have a lot of bald spots in our yard that we can’t seem to get rid of. Diagnosing is necessary – compaction, water issues, fertility problems. Loosen area and make sure water is able to move into soil. Then can reestablish grass.
Q: If your centipede lawn is spotty with a variety of weeds, would it be better to kill the whole thing off and sod with Zoysia? Centidegrass and zoysia have different pH requirements so may not be as simple as just replacing with new type of grass. Why is centipedegrass not doing well? Soil testing and cultural practice evaluation before considering to replace grass. Current centipedegrass may just need different care to thrive.
Q: What is the best alternative to turf grass? Perennial peanut is an option as a vegetative cover. It does freeze back in many spots of North Florida. It does creep and there are many cultivars. Edging is necessary. Sunshine mimosa is an option but it also freezes back. Lyre leaved sage for shady areas.
Silkgrass for drier areas. Frogfruit for moist areas
Final thoughts from Dr. Unruh Shut the irrigation off. Most people tend to overwater. Back off inputs to as needed instead of a schedule. A few weeds are ok for most home lawns and lawns can still be attractive.
Rudbeckia hirta, commonly known as black-eyed Susan, is a vibrant and hardy wildflower with golden-yellow petals and a dark brown central cone. Photo by kburgess, Adobe Stock.
Florida’s diverse ecosystem showcases a remarkable array of native wildflowers that burst into vibrant colors, particularly during the spring season. Cultivating these indigenous blooms not only enhances the beauty of your lawn but also fosters biodiversity. Florida’s spring landscape comes alive with a vibrant tapestry of native wildflowers, each species contributing its unique charm to the natural scenery.
Yellow, a color that beckons pollinators, especially bees and butterflies, is a prevalent hue among these wildflowers. Many have evolved to showcase bright yellow tones, attracting pollinators, and ensuring the vital transfer of pollen for the continued existence of the plant species. In this spotlight, we’ll explore a selection of my favorite yellow-blooming wildflowers: Leavenworth’s tickseed, dune sunflower, and black-eyed Susan.
Leavenworth’s Tickseed
Leavenworth’s tickseed showcases brilliant yellow flowers with distinct maroon markings, contributing to its charm as a cheerful and attractive wildflower in gardens and meadows. Photo by Sunshower Shots, Adobe Stock.
Coreopsis, Florida’s state wildflower, boasts 14 native species flourishing in North Florida. Among these, Leavenworth’s tickseed (Coreopsis leavenworthii), predominantly found in Florida, graces the Panhandle region with its distinctive yellow, daisy-like flowers adorned with dark centers and scalloped yellow ray florets.
Thriving in open areas, flatwoods, and prairies, this annual or short-lived perennial becomes a beacon of color in the spring landscape. Ideal for wildflower gardens, Leavenworth’s tickseed requires adequate space for reseeding, best achieved by planting one to two feet apart in the spring for optimal flowering. The plant quickly establishes itself in moist soils, benefiting from occasional pruning or mowing to encourage a second flush of flowers.
Preferably rooted in sandy, well-drained soil, Leavenworth’s tickseed demands full sun exposure for maximum flower production, with moist soils playing a pivotal role in reseeding and maintaining this distinctive species.
Beach Sunflower
Adapting well to both coastal and inland environments, the beach sunflower attracts butterflies and other pollinators with its vibrant blooms. Photo by Nahhan, Adobe Stock.
The beach sunflower (Helianthus debilis), also recognized as the dune sunflower, is renowned for its coastal charm and nearly year-round blossoms. Adapting gracefully to both coastal regions and inland landscapes, this sunflower showcases two-inch flowers resembling daisies or sunflowers, boasting yellow petals and brown centers. A captivating trait is its tendency to follow the sun throughout the day.
When cultivating beach sunflowers, it is essential to allocate ample space for their spreading nature. To maximize visual impact, consider planting them in masses, maintaining distances of three to four feet between each plant. As beach sunflowers may become unruly over time, periodic removal of old stems is advisable. Encouraging new plants to sprout from seeds contributes to a healthier growth pattern. Light trims every three months can further enhance the foliage’s vibrancy and overall maintenance. While acting as an annual in freezing temperatures, the beach sunflower generally reseeds itself and displays admirable tolerance to coastal elements, including salt and wind.
For optimal growth conditions, planting in full sun encourages abundant flowering, although the plant can tolerate light shade for part of the day. Preferably, choose well-drained sandy soils, avoiding persistently moist conditions to ensure the overall health and vitality of the beach sunflower.
Black-eyed Susan
Black-eyed Susans are not only visually appealing but also serve as valuable nectar sources for pollinators, attracting butterflies, bees, and other beneficial insects to the garden or natural habitat. Photo by Green Stock Creative, Adobe Stock.
Black-eyed Susan (Rudbeckia hirta), a classic native bloom, captivates with its widespread availability and versatile nature as an annual, biennial, or perennial. This resilient plant grows to a height of one to two feet, showcasing rough-textured leaves and deep-yellow aster-like flowers with dark brown disk flowers forming a central dome.
When incorporating black-eyed Susans into your landscape, consider their suitability for mixed wildflower beds, where they effortlessly self-seed in open or lightly mulched areas. Maintaining proper spacing of 14 to 18 inches between plants, vigilant monitoring during extended dry periods, and providing deep watering, when necessary, contribute to the overall health and vitality of these iconic blooms.
Thriving in well-drained soils, black-eyed Susan showcases adaptability to various soil types. Whether exposed to full sun or partial shade, the plant optimizes its blooming potential, enhancing the visual appeal of any landscape.
Encourage Wildflowers in Your Landscape
Selecting native wildflowers adapted to your landscape’s specific soil, light, and drainage conditions is crucial for success. If initial attempts fail, try different species until you find the perfect match, emphasizing the importance of using the right plant in the right place. Thorough watering aids in establishment, but once native wildflowers are established, they generally require minimal irrigation. Avoid overwatering to prevent fungal and rot issues.
Native wildflowers in Florida typically do not need additional fertilization, as it can lead to rapid growth and increased susceptibility to pests and diseases. Embrace the natural resilience of these plants by avoiding unnecessary fertilization. Encourage the persistence of wildflowers by embracing self-seeding, maintaining open, lightly mulched areas for natural germination, and being vigilant when weeding.
Florida’s spring blooming wildflowers, including Leavenworth’s tickseed, beach sunflower, and black-eyed Susan, contribute to the state’s biodiversity. Selecting the right species and providing proper care allows us to cultivate these native blooms and actively participate in conserving Florida’s precious ecosystem.
Weeds can be the bane of the gardener’s existence and Extension Agents get a lot of questions on how to manage them throughout the year. Whether you are growing edibles, ornamentals, or turfgrass you have probably encountered a plant out of place which is basically the general definition of a weed. Just like with any other landscape challenge the first thing you need to do when dealing with weeds is accurate identification. Understanding the life cycle of the pest (weed in this case) you are targeting will be key for the most effective control with minimal inputs. Your local Extension office can assist with weed identification, and you can find a list by county here.
If you missed the live broadcast, you can watch the video on YouTube
Below are the links that were shared during the episode in the order discussed if you would like to follow along:
We have one more episode of Gardening in the Panhandle LIVE! scheduled this year on October 12th. We hope you will join us for Herbs and Cool Season Edibles!
Weed control is never ending in Florida landscapes. If there is a bare area of soil, weeds take advantage of that void and make themselves at home. Ideally, we would use good cultural practices that minimize weed invasion, but if prevention is ineffective and you need to use an herbicide, make sure you are using that tool properly.
When I talk to homeowners and commercial applicators about weed control, many times they have selected the appropriate product but are still struggling with management. While troubleshooting the problem, many times I discover, the reason is related to poor uptake because the client is not making herbicide applications to what I like to call “happy weeds.”
When using an herbicide, you need to think about how it works. Not the deep level chemical reactions, but rather consider how the active ingredient is going to be delivered to whatever physiological function of the plant it is targeting.
Does the herbicide need to be absorbed by the leaves/stems/roots?
Once absorbed, does it need to travel through the vascular system of the plant (translocation)?
What effect will temperature, moisture, mowing/trimming have on product uptake?
All these factors are very important because if a plant is stressed, the primary response is survival. During excessively hot weather plants close off stomata, form waxier surfaces, and do everything they can to retain moisture – which also includes reduced absorption of herbicides. In cool weather, the plant may be dormant or have slowed growth that will reduce translocation.
Mowing and trimming reduces leaf surface area minimizing uptake. Overcoming injury also triggers the plant to go into water conservation mode which also limits product uptake.
So, what do I mean by “happy weeds”? For herbicides to be effective, they should be applied when growing conditions are ideal for your target plant. Optimum soil moisture, soil temperature, ambient temperature, and minimal stress lead to “happy weeds” that are primed to accept herbicides and translocate if needed. Plants in survival mode will have their defenses activated and this decreases herbicide efficacy.
Always read and follow entire label instructions of all pesticides.
Chamber bitter is a weed commonly found in Florida landscapes.
Photo by Beth Bolles, UF Extension Escambia County
