Know How to Choose Florida-Friendly Plants

One of the main Florida-Friendly Landscaping principles is to plant the right plant in the right place. In Florida, not only does this apply to the zone you’re in, soils you have, and light conditions in your garden, but also ensuring that invasive, exotic plant species are not used. While most of us have heard about invasive, exotic plants – those that invade and disrupt our unique natural habitats – some may not know where or how to find out which plants are, in fact, invasive and exotic. Some of the more famous invasive, exotic plant species, such as kudzu and hydrilla, are familiar to us and we may have an idea of a plant in our garden that is “aggressive”, but how do we know for sure? Since only a handful of the worst invasive, exotic plants are legally prohibited from being sold, how do we know if a plant we are considering purchasing at our local nursery or another plant already in our gardens is an invasive, exotic? A quick internet search for Florida invasive plants gets you various sources of information. How do you choose which to use?

The unique habitats of Florida need our help. Prevent the spread of invasive, exotic species by planting Florida-Friendly plants. Source: Mark Tancig/UF/IFAS.

Fortunately, the researchers at UF/IFAS want you to be able to find the best information in one spot – the UF/IFAS Assessment of Non-Native Plants in Florida’s Natural Areas. This site systematically reviews individual plant species and provides a recommendation as to whether it should be used in North, Central, or South Florida landscapes. Many landscape plants have been reviewed – over 800 – and more are added to the site as reviews are completed. The UF/IFAS Assessment also reviews cultivars of known invasive, exotic plants to ensure that they are sterile and will not revert back to their wild type or hybridize with known invasives, or even closely related native species.

The UF/IFAS Assessment is a simple, convenient source for deciding if a plant should be used in your Florida landscape.

To use the site, simply visit the main web address – assessment.ifas.ufl.edu – and begin typing in your plant name in the search bar. You can begin spelling the scientific or common name and it will start showing possible results as you type. Once you select the plant you’re interested in, it will take you to a new page with photos of the plant, some general information, additional links, and, most importantly, the assessment conclusion for each zone. The conclusion will be one of the following:

  1. Not considered a problem species at this time,
  2. Caution, or
  3. Invasive

Of course, if it’s not a problem, then feel free to use and share that particular plant. If it is a caution plant, then it may be used, but you will want to be extra careful in where you plant it. Those may be better suited as potted plants or planted in areas that are confined, to limit its potential spread. If it’s invasive, don’t plant it.

Caution plants are reassessed every two years while those that are not considered a problem species or are considered invasive are reassessed every ten years.

Another way to use the UF/IFAS Assessment is to filter all reviewed plants by various criteria you’re interested in. If you select assessments on the main page, it will lead you to a list of all reviewed plants. A filter button allows you to choose geographic zone, conclusion type, and growth habit, among some other criteria. This will create a list that can then be exported to a Microsoft Excel table.

As you can see, UF/IFAS is trying to make it easy for you to determine which plants can be used in the landscape without potentially spreading and causing disruption to our unique natural areas.

If you have any questions about individual species that have or have not been assessed, contact your local County Extension Office.

Prevent Asparagus Fern Escapes

Prevent Asparagus Fern Escapes

As an extension agent, I’m always curious of what plants folks are using in the landscape. One plant I’ve been noticing more and more of in north Florida, both in containers and in landscape beds, is asparagus fern. Three different plant species go by the name asparagus fern – Sprenger’s fern (Asparagus aethiopicus), foxtail fern (Apsaragus densiflorus), and lace fern (Asparagus setaceus). Property owners should refrain from selecting these plants since they are another example of invasive, exotic species that can spread to natural areas and effect native plant communities.

Native to South Africa, Asparagus species are technically not a fern, but related to lilies, and, yes, asparagus. Its ease of growth has made them a go-to choice for gardeners looking for a hardy, attractive plant. Unfortunately, the red berries that follow the small, white, scented flowers are fed on and spread by birds. The seeds germinate easily and can become established in other parts of the garden or, even worse, a local natural area. The ability of Sprenger’s fern to spread into and disrupt natural ecosystems has earned it a spot on the Florida Exotic Pest Plant Council’s List of Invasive Species as a Category I invasive plant. Category I plants are reserved for those plants that have been documented as causing ecological harm to Florida’s ecosystems. Foxtail fern and lace fern should also be used with caution.

 

Asparagus fern in a storefront planter. Photo Credit: Mark Tancig.

 

Birds can carry the red berries near and far. Photo Credit: Mark Tancig.

To remove asparagus fern from the landscape, manual or mechanical removal can be effective for small areas. Be careful to dig up all roots. For larger areas, the use of a dilute glyphosate herbicide product will provide control. Retreatment may be necessary.

If you’re looking for other alternatives to asparagus fern, try these Florida-Friendly alternatives: Coastal sunflower (Helianthus debilis), coontie (Zamia pumila), Coleus (Plectranthus scutellarioides), or Cast Iron plant (Aspidistra elatior).

 

Coastal sunflower. Photo Credit: UF/IFAS.

 

Coontie. Photo Credit: UF/IFAS.

 

Coleus. Photo Credit: UF/IFAS.

Cast iron plant. Photo Credit: Julie McConnell.

 

 

Welcome the Air Potato Leaf Beetle

Welcome the Air Potato Leaf Beetle

Air potato leaf beetle. Photo credit: Les Harrison, UF/IFAS.

A small, but brightly colored beetle has appeared in north Florida: the air potato leaf beetle (Liliocetis cheni), a native of East Asia. The beetle, less than half an inch long, has a candy apple red body that stands out against green leaves and the more muted earth tones of most other bugs. The striking bright glossy red coating would be the envy of any sports car owner or fire truck driver.

Unlike other arrivals to the U.S., this insect was deliberately released in 2012 for biological control of air potato. After years of testing, approval was finally given to release air potato leaf beetles to begin their foraging campaign against this invasive plant species. The beetle has very specific dietary requirements and only can complete its life cycle on air potato. The larvae and adults of this species consume the leaf tissue and occasionally feed on the tubers.

When a population of air potato leaf beetles finish off an air potato thicket, they go in search of nourishment from the next patch of air potato. They are sometimes seen during stopovers while in search of their next meal.

Air potato (Dioscorea bulbifera) is an herbaceous perennial vine which is easily capable of exceeding 60 feet in length. It quickly will climb over any plant, tree or structure unfortunate enough to be in its vicinity. The vine also produces copious quantities of potato-like tubers suspended from its vines. Unless collected and destroyed, most of the easily camouflaged potatoes will germinate and intensify the infestation.

Air potato. UF/IFAS Photo: Thomas Wright.

Air potato. UF/IFAS Photo: Thomas Wright.

Air potato came to Florida in 1905 from China and quickly escaped into the wild. By the 1980’s it was a serious pest species in south and central Florida, but has gradually become established in the panhandle, too. Chemical control of the air potato has been difficult. Repeated herbicide treatments are required to kill a thicket with multiple plants.

Unlike the air potato leaf beetle that only eats air potato, kudzu bugs eat their namesake vine (kudzu), but also feed on a number of other plants including a wide selection of valuable legumes and be quite destructive. Kudzu bugs were accidently introduced in north Georgia in 2009 and have spread across the south in the ensuing years and become established in north Florida.

It is a pleasant surprise to know air potato leaf beetles are working to limit the invasive air potato vine, but it is sad to think there is plenty more for them to eat.

To learn more about the air potato and the beetle:

Natural Area Weeds: Air Potato (Dioscorea bulbifera)

Air Potato Leaf Beetle Publication

Skunkvine – A Stinky Invasive Plant

Skunkvine – A Stinky Invasive Plant

Skunkvine illustration. UF/IFAS Center for Aquatic and Invasive Plants.

Skunkvine illustration. UF/IFAS Center for Aquatic and Invasive Plants.

North Florida gardeners have many non-native, invasive plants to deal with, but none quite as stinky as skunkvine (Paederia foetida). As the name implies, skunkvine has a noticeable smell, especially when the leaves are crushed, and it is an aggressive-growing vine, capable of smothering desirable landscape plants. Gardeners should learn to recognize and control this plant before it gets a foothold in the garden.

Skunkvine is native to eastern and southern Asia and a member of the coffee family (Rubiaceae). It was introduced to Florida prior to 1897 as a potential fiber crop, but quickly spread and is now considered a Category I invasive plant by the Florida Exotic Pest Plant Council (FLEPPC) and as a noxious weed by the Florida Department of Agriculture and Consumer Sciences (FDACS).

Skunkvine can be identified by the following characteristics:

  • Aggressive twining vine
  • Leaves are opposite each other
  • There is a thin flap of tissue on the stem between the leaves
  • Leaves have a strong skunk-like odor when crushed
  • Clusters of small, tubular, lilac-colored flowers appear in late summer to fall
  • Fruits are shiny brown and can persist through winter

 

Skunkvine flowering. Photo by Ben Ferrin (UF/IFAS).

Skunkvine flowering. Photo by Ken Ferrin, UF/IFAS Center for Aquatic and Invasive Plants. Used with permission.

 

Once you have identified skunkvine in your garden, the next step is to work to remove it. For small patches, pulling by hand can be effective but will require monitoring to ensure it doesn’t resprout. When hand pulling, you want to be sure to get as much of the root as possible. For larger areas, chemical control using herbicide products that contain triclopyr, imazapic, or aminopyralid are most effective. Carefully reading the product label will help determine which product to purchase.

Since skunkvine can be easily spread by seed and fragments of stem, care must be taken when disposing of it. The best solution is to place plant debris into a trash bag and dispose of it with your regular household garbage.

By knowing how to identify and manage skunkvine, north Florida gardeners can keep it from stinking up their own gardens, their neighbor’s gardens, and surrounding natural areas that support our native wildlife.

 

References:

Langeland, K. A., Stocker, R. K., and Brazis, D. M. 2013. Natural Area Weeds: Skunkvine (Paederia foetida). Agronomy Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. EDIS document SS-AGR-80.

Fire Ants in the Garden

Fire Ants in the Garden

Ants can be treated with spinosad in vegetable gardens. Photo by Molly Jameson.

Ants can be treated with spinosad in vegetable gardens. Photo by Molly Jameson.

 

There’s nothing worse than sinking your fingers into your garden soil to dig up a potato, plant a seedling, or pull up a radish, and be met with a sharp, painful sting, and little red critters rocketing up your arms. If you are a gardener in the panhandle, my bet is that you know exactly to what I refer: fire ants!

Fire ants are certainly not native to our area. These guys are an invasive species from South America that are very resilient, and many are territorial, with the potential to drive out any native ant populations. Fire ants arrived in the 1930s, and can now be found throughout most of the southeastern United States.

So when you end up with fire ant mounds engulfing your carrot patch, what can be done? Since fire ants in your garden mean fire ants in your food, the least toxic control methods are of high importance and conventional broadcast bait treatments and mound treatments should be avoided. Even in your lawn, be careful when using strong insecticidal bait treatments, as these can harm the native ant populations that help control the spread of fire ants. This can then lead to a strong resurgence of fire ant populations that can outcompete the native ants.

Although completely controlling fire ants in an area is not possible, there are sustainable management techniques that can help. Some fire ant colonies have a single queen while others have multiple queens. Either way, in order to eliminate a fire ant colony, all queens in the colony must be killed. Fire ants are omnivorous, in that they eat plants, insects, sugars, and oils. The catch is that they are only able to ingest liquids, so solid food must be brought into the colony, where larvae regurgitate digestive enzymes onto the food, breaking it down into liquids. Therefore, any method of control by ingestion will need to be in liquid form, or the ants must be able to bring the material into the colony, without first being exterminated.

Fire ants can become a problem around and in raised vegetable gardens. Photo by Molly Jameson.

Fire ants can become a problem around and in raised vegetable gardens. Photo by Molly Jameson.

There are some commercially available products that contain boric acid or diatomaceous earth. These products may reduce populations, but eliminating whole colonies with these products can be a challenge.

The use of a nervous system toxin called spinosad is effective on fire ant populations and is considered safe to use in vegetable gardens. This toxin comes from a bacterial fermentation process, and is therefore considered organic. But be aware, even though there are organic products with ingredients derived from botanical sources such as rotenone and nicotine sulfate, they should not be used in vegetable gardens. When using chemical methods of control, always follow the directions on the label carefully.

One physical method of control is the use of hot water. Three gallons of scalding water, which is between 190 to 212ºF, has been used on colonies with a success rate of 20 to 60 percent, when applied in several treatments. You will want to slowly pour the water on the colony, being extra careful not to get burned, and avoid injuring any surrounding plants. If you are like I am, and you often leave your garden hose in the hot sun, you can spray the ant colonies with the hot water, as you wait for the water to cool off enough to water the garden. Hot water control takes persistence, but you can eventually drive the ants out.

Another method of physical control is excavation. This requires digging up the mound, putting it in a bucket, and taking it to another location. Apply talcum or baby powder to your shovel handle and bucket to help prevent the ants from escaping and crawling up to sting you.

One reason fire ants are so rampant in the United States is that they have little competition or natural enemies. Scientists have released multiple species of phorid flies, natural parasites of fire ants in South America, and a few species have become established. Scientists at UF/IFAS are currently researching additional fire ant biological control methods, such as the use of a fungi, which has shown promise.

Remember, not all ants in the garden are bad guys! Many species act as roto-tillers, aerating and redistributing nutrients in the soil. They also play a role as decomposers as they assist in turning dead insects into soil nutrients. Ants can disturb garden pests by attacking them or interrupting their feeding, mating, and egg laying processes. Additionally, ants are a food source for wildlife, such as other insects, frogs, lizards, birds, spiders, and even some mammals.  

 

Purple Triangles in the Trees

Purple Triangles in the Trees

From time to time I am reminded of how little I know.  Honestly, I am reminded on a daily basis. A few weeks ago someone asked me about the purple things hanging from the trees. Luckily, the person gave me some good southern directions on where I could find one of these things hanging around in Marianna. So I drove out to the site to get a better look. What I saw hanging in the tree was a three-sided, purple triangle about two feet tall and a foot wide.  It looked to me like someone got a box kite stuck in a tree. Upon further research, it was determined this box kite like thing was a monitoring trap for the emerald ash borer (EAB).

A woman hanging an emerald ash borer trap in a tree. Photo Credit: Texas A&M University

A woman hanging an emerald ash borer trap in a tree. Photo Credit: Texas A&M University

The emerald ash borer (EAB) is a destructive, exotic wood-boring beetle native to Asia. It was first discovered in North America in July 2002 and has made a home in Michigan, Ohio and Ontario, Canada. Millions of ash trees have been killed by the EAB in Michigan and invested ash tree nursery stock in other states indicates the potential for increased spread of the pest. EAB has made its way to the south and has been found in Louisiana and Arkansas.

Monitoring traps are not the only means of EAB detection. A proactive approach utilizing observant citizens can help keep an eye out for potential populations. You can use these tips to monitor your community for emerald ash borers:

Ash Tree Identification – Ash trees are identified by their (1) opposite branching pattern, (2) compound leaves with 5-9 leaflets, and (3) diamond shaped bark ridges on mature trees.

A compound leaf of an ash tree. Photo Credit: FDACS

A compound leaf of an ash tree. Photo Credit: FDACS

Woodpecker Damage – Of course, not all woodpecker damage on ash trees is associated with EAB infestation, but woodpecker damage in the upper part of the tree can indicate their presence.  The woodpecker damage is usually accompanied by vertical cracks in the bark.

Canopy Thinning – As the attack progresses, bark cracking continues and the canopy in the upper half of the tree begins to thin.

Michigan ash tree showing decline due to Emerald ash borer. Photo Credit: USDA

Michigan ash tree showing decline due to Emerald ash borer. Photo Credit: USDA

Tunnels and Holes – The emerald ash borer makes distinctive S-shaped tunnels that differ from damage from other borers.

EAB Damage (left) VS Other Borer Damage. Photo Credit: Texas A&M University

EAB Damage (left) VS Other Borer Damage (right). Photo Credit: Texas A&M University

This beetle hitchhikes on firewood and infests new areas at an alarming rate.  Although the EAB has not yet been detected in Florida, transporting firewood from other states puts Florida ash trees at risk. Your help is needed to detect possible infestations so they can be quickly eradicated. The information available at the following links will help you identify the EAB, EAB host trees, and infestation symptoms.