Invasive Species of the Day: Cuban Tree Frog and Hydrilla


Cuban Treefrog (Osteopilus septentrionalis):

Image by Dr. Steve A Johnson 2005.

Image by Dr. Steve A Johnson 2005.

The Cuban Treefrog: was introduced into Florida as a stowaway on vehicles and plants in the 1920’s. As of 2013, breeding populations have been recorded as far north as Georgia. Cuban Treefrogs have larger toepads and eyes than any of the native species. Being larger in size, the Cuban Treefrog out-competes other treefrogs for resources, to the point that they are predators of Florida’s treefrogs and inhibitors of native tadpoles.

Juvenile Cuban Treefrogs can be distinguished from natives by their red eyes and hind legs with blue bones. Three-foot-long sections of 1.5 inch diameter PVC pipe can be placed in the landscape to monitor for treefrog species. Should Cubans be found, they should be reported and euthanized. For additional details visit:

Would you like to be a Citizen Scientist?  You can help Dr. Steve Johnson at the University of Florida Department of Wildlife Ecology and Conservation by reporting suspected Cuban Treefrog sightings.  For more information on how you can become a Citizen Scientist, visit The Cuban Treefrog Citizen Scientist Project.

For more information contact the author Sheila Dunning, UF/IFAS Extension Okaloosa County Commercial Horticulture Agent 850-689-5850.

Hydrilla (Hydrilla verticillata):

Hydrilla is a perennial submerged plant that grows in dense mats up to the surface of freshwater habitats, including ponds, lakes, springs, and rivers. Growing at the rapid rate of an inch a day and up to 25 feet long, hydrilla shades out beneficial native plants and clogs waterways, preventing flood control, boating, and fishing. In dense populations, the plant can alter oxygen levels and water chemistry and survive in a wide variety of nutrient conditions, sunlight availability, and temperatures.

Hydrilla Photo Credit: Vic Ramey, UF

Hydrilla Photo Credit: Vic Ramey, UF/IFAS Center for Aquatic and Invasive Plants.

Originating in Asia, it was introduced to Florida (likely through Tampa and Miami) in the 1950’s as part of the worldwide aquarium trade. Hydrilla has become a very expensive problem for the state. Millions are spent annually on chemical and mechanical treatment simply to maintain the plant. Adding to the problem is the fact that it is still available commercially, even though it has been placed on the US Federal Noxious Weed List. In the United States, the plant is found as far north as Connecticut and west to California and Washington.

Methods of control include mechanical harvesters and chopping machines (although fragments of hydrilla left in the water can regrow), introduced insects and fish (particularly the Chinese grass carp), aquatic herbicides, and lake drawdowns. Hydrilla is often transported from one body of water to the other by unknowing boaters moving fragments of the plant left on boats, trailers, or live wells, so learning to identify the plant and cleaning boats before leaving the ramp are helpful in prevention. Visit the Extension Hydrilla IPM site for more helpful tips.

For more information contact the author Carrie Stevenson, UF/IFAS Extension Escambia County Coastal Sustainability Agent at 850-475-5230.

Invasive Species of the Day: Tiger Prawn and Climbing Ferns

Invasive Species of the Day: Tiger Prawn and Climbing Ferns


Giant Tiger Prawn (Penaeus monodon):

Giant Tiger Prawn: This large shrimp, also known as the Asian Tiger Shrimp and the Black Tiger Shrimp, can reach lengths between 8-12 inches.  It resembles are native edible penaeid shrimp but differs in that it has distinct black and yellow stripes. It was brought to the U.S. from the Indo-Pacific region as an aquaculture product.  There was an accidental release of 2,000 animals from a South Carolina farm in 1988.

The nonnative Giant Tiger Prawn - also known as the Black Tiger Shrimp. Photo by David Knott,

The nonnative Giant Tiger Prawn – also known as the Black Tiger Shrimp. Photo by David Knott,

Reports of this shrimp in the wild have increased over time.  They have been found in all Gulf coast states and there has been at least 1 record in each of the Florida Panhandle counties.

The impact of this shrimp to our area is still unknown but they have a high tolerance for salinity change and consume many types of benthic invertebrates.  It is thought that they could become serious competition for our native penaeid shrimp and could possible transmit diseases.

If you think you have found one of these shrimp, record size location (GPS preferred), and email information to  To learn more about this species view the USGS factsheet.

For more information contact the author Rick O’Connor, UF/IFAS Escambia County Extension – Sea Grant and Marine Science Extension Agent, 850-475-5230.

Climbing Ferns (Lygodium japonicum and Lygodium microphyllum):

Japanese Climbing Fern (Lygodium japonicum) and Old World Climbing Ferns (Lygodium microphyllum): are presently the only non-native invasive ferns in Florida.  Both ferns reproduce and spread readily by wind-blown spores. A single fertile leaflet can produce 28,600 spores.  Animals, equipment, and even people that move through an area with climbing ferns are very likely to pick up spores and move them to other locations on the property or even to other properties.

Japanese Climbing Fern Lygodium japonicum photo by Chris Evans, Illinois Wildlife Action Plan,

Japanese climbing fern is a delicate looking perennial climbing vine.  It is capable of forming a dense mat-like thatch capable of covering trees and shrubs. Initially, it was introduced from Japan as an ornamental. It is scattered throughout the lower portions of Alabama, Georgia, Louisiana, South Carolina, and south into central Florida. Further planting or cultivation of this vine is prohibited by the Florida Department of Agriculture and Consumer Services.  It climbs very quickly to the crowns of pine trees, which can move fire into the growth points during controlled burns, making it a concern on forested lands.

Old World climbing fern has been a problem for many years in central and south Florida but it is currently moving north. The first plant was documented in 1958 by a nursery in Delray Beach.  By 1965, it was found in natural areas of Marion County.  The northern edge of its advance by 2012 was Hernando County on the Gulf side and Duval County on the Atlantic coast.

Adequate control of both climbing ferns has been achieved with multiple applications of glyphosate and/or metsulfuron. Other herbicides, such as triclopyr and imazapic have also been used to
control Japanese climbing fern.  However, when the plant is growing in areas adjacent to wetlands or water, fewer herbicides are registered for those sites.  Hand digging is also an option, except when the fern is producing spore covered leaflets.  Disturbing it then would propagate more plants.

Old World Climbing Fern has moved northward from South Florida into Central Florida. Photo by Peggy Greb, USDA Agricultural Research Service,

Old World Climbing Fern has moved northward from South Florida into Central Florida. Photo by Peggy Greb, USDA Agricultural Research Service,

As with most invasive plants, repeated and correctly timed treatments are likely to be necessary. For more information about climbing ferns contact your local UF/IFAS Extension Office and read the following publications: and

For more information contact Les Harrison, UF/IFAS Extension Wakulla County – Agriculture & Natural Resources Extension Agent by phone at 850-926-3931.






Invasive Species of the Day (February 25): Coral Ardisia and Wild Hogs

Invasive Species of the Day (February 25): Coral Ardisia and Wild Hogs


Coral Ardisia (Ardisia crenata):


photo courtesy of Les Harrison

Attractive red berries entice homeowners to use as a landscape plant but coral ardisia can quickly dominate adjacent natural areas. photo courtesy of Les Harrison

Coral ardisia is also known as coral berry, spice berry, and scratchthroat. It was introduced into Florida in the early 1900’s for ornamental purposes.

In the ensuing years, it has since it escaped cultivation and has become established in hardwood hammocks and other moist woods of natural areas and grazing lands. Populations can currently found in Florida, Louisiana and Georgia.

This evergreen sub-shrub reaches a height of 1.5 to 6 feet and tends to grow in multi-stemmed clumps. Leaves are alternate, 8 inches long, dark green above, waxy, without hairs, and have scalloped margins and calluses in the margin notches.  Flowers are typically pink to white in stalked axillary clusters, usually drooping below the foliage. The fruit is a bright red, globose, single-seeded berry, measuring approximately 0.25 inches in diameter. White-berried populations are also known to exist.

Coral ardisia is classified a Category I weed on the Florida Exotic Pest Plant Council Invasive Plant List.  Control of coral ardisia may be accomplished by two methods. A low-volume foliar application of Garlon 4 or Remedy provides suppression of this plant.  Complete foliar coverage is essential to success and re-treatment will be necessary for complete control.  Basal bark applications with Garlon 4 or Remedy in an oil carrier can also be utilized for suppressing this invasive weed. Do not apply more than 8 quarts of Remedy or Garlon 4 per acre and treat no more than ten percent of the total grazed area if applying greater than two quarts per acre.

More information is available at

For local assistance, contact your county UF IFAS Extension office.

For more information contact Les Harrison, UF/IFAS Extension Wakulla County – Agriculture & Natural Resources Extension Agent by phone at 850-926-3931.


Will Sheftall Natural Resources Agent with UF/IFAS Extension Leon County exams the impacts of invasive coral ardisia on local urban forests in Northwest Florida.

Wild Hogs(Sus scrofa):

Wild Hogs, also called Feral Hogs, are not native to the U.S.  Wild hogs are highly adaptable and can find suitable habitat easily.  Wild hogs can be all shapes, sizes and colors since they are hybrids of many different breeds.   Wild hogs sometimes resemble their domestic relatives but sometimes resemble their Eurasian backgrounds.

Wild hogs are probably the most prolific large mammals in the world.  They reach sexual maturity at a young age.  Females have multiple litters of 3-8 piglets per year.  Natural mortality rates are low.  Wild hog females and young live and travel in groups called sounders.  Sounders typically have 1 to 3 adults and several young.  When females reach maturity, they either stay with the sounder or they go out and form a new sounder with other young females.  Young males leave the sounder alone at about 16 months.

Wild hogs are opportunistic omnivores that feed by rooting and grazing.  This rooting behavior is why we consider them to be a pest.  The impact of wild hogs on the environment is soil erosion, decreased water quality, spread of other invasive plants, damage to agricultural crops, and damage to native plants and animals.  They have been documented as threats to threatened and endangered species.  They can significantly impact populations of reptiles, amphibians, small mammals, ground nesting birds and even deer.

Wild hogs pose a health risk to humans because they can carry numerous diseases and parasites.  Care should be taken when handling wild hogs.  Wear gloves, cover any open wounds, and wear clothing that can be cleaned thoroughly.

Wild hog damage to pond bank.  Photo by Jennifer Bearden

Wild hog damage to pond bank. Photo by Jennifer Bearden

Human hunting is the most significant cause of mortality in wild hogs, although hunting alone will not control hog populations in a good habitat.  The most effective way to remove wild hogs from a location is a combination of trapping and shooting.

In Florida, wild hogs may be hunted year round on private land (with permission of the landowner) and at night with no permit required.  Hogs may be trapped year round.  Wild hogs cannot be trapped and released onto public land.  Trapped wild hogs can only be transported with a permit from FDACS) to slaughter or to an approved Feral Swine Holding Facility.  For more information on Wild Hogs, go to: and .

Invasive Species of the Day (February 24): Lionfish and Air Potato

Invasive Species of the Day (February 24): Lionfish and Air Potato


Lionfish (Pterois volitans):


Red Lionfish  Photo: Florida Sea Grant

Red Lionfish
Photo: Florida Sea Grant

Red Lionfish are a predatory reef fish that are non-native invasive species and have spread throughout Florida Waters.  They are members of the family Scorpaenidae whose members are venomous and the lionfish is no exception.  This fish is relatively small ranging from 10-12 inches in length and have a zebra-like appearance with long, showy pectoral fins.  They have a row of long dorsal spines that contain venom glands.  Their native range is the South Pacific and Indian Oceans and preferred habitat is on offshore reef structures.  These fish are considered to be voracious eaters feeding on native fish, reducing vital native populations, and competing for food with native fish such as grouper and snapper.


With few predators, these fish are thriving in Florida waters, even in the northern Gulf of Mexico.  They reproduce often, under good conditions as often as every 3-4 days, with eggs hatching after about two days.  They also consume a variety of local species.  Research has found in some cases there has been an 80% decline in reef fish recruitment and loss of some economically important species.  These fish are able to expand their stomachs for large meals and can survive starvation for over 12 weeks. Lionfish are an invasive species in our local waters and removal is encouraged.

The most effective control of this species is removal by spearfishing; though some recent reports of hook and line capture using live bait have occurred.  Lionfish are cryptic and nocturnal but local divers have found them hovering near reefs at midday.  Florida Fish and Wildlife Conservation Commission (FWC) changed regulations to increase harvesting opportunities.  Such changes include no requirement for a recreational fishing license when using spearing devices (pole spear, a Hawaiian Sling, handheld net, or spearing devices marked for use on lionfish), and no recreational or commercial bag limit; though recreational fishing license is required for other fishing methods.  Check the FWC regulations before fishing or diving for these species.


Lionfish are venomous, must be handled carefully, venom glands occur on the dorsal, pelvic and anal spines.  Lionfish sightings can be reported at 877.786.7267, the newly released FWC lionfish app,or (if in the Pensacola area) the lionfish map.  If stung the wound can be treated with warm (but not scalding) water.  You may need to seek medical attention as soon as possible.  Rarely are stings fatal unless the person has an allergic reaction.  The Poison Help Hotline can be reached at 800.222.1222.  Inshore sighting information is being collected by Florida Sea Grant in Escambia County to track the movement of these species.  You can fill out the online report on the USGS website or the REEF website and stay up to date on research as it pertains to this species at the new NOAA lionfish portal and Florida Sea Grant.

For more information contact the author Rick O’Connor, UF/IFAS Escambia County Extension – Sea Grant and Marine Science Extension Agent, 850-475-5230.

Air Potato (Dioscorea bulbifera):


Large heart-shaped leaves completely cover this fence-row in Bay County.  Photo by Julie McConnell.

Large heart-shaped leaves completely cover this fence-row in Bay County. Photo by Julie McConnell.

Air potato is a tall climbing herbaceous plant that is in the yam family and can overtake natural and urban areas in a very short time. Air Potato uses twining tendrils that allow it to quickly climb over shrubs, trees, and man-made structures. The large heart-shaped leaves and potato looking “bulbils” that hang from the vine make identification fairly easy. The bulbils spread the growth of the plant, along with underground tubers. The plant will die back during the winter, but unless the vines, bulbils and underground tubers are removed, it will come back in the spring. The air potato is native to Asia and was introduced in Florida in the 1905. The potato is not good to eat and in some cases, may be poisonous.

There are a number of ways to control this species, and using a combination of methods may lead to greater success. Eliminating the vines and bulbils by collecting them, be sure to dispose of them where they will not be spread to other areas. The bulbils and underground tubers cannot survive freezing temperatures, so placing them in a freezer for a day and then disposing of them will help eliminate new growth.

Some cites in Florida have sponsored activities that involve the community in gathering air potato and other invasive species. Collecting the bulbils and underground tubers is easiest to do during the winter, when the green vegetation has dies back.

Herbicide treatments are best when applied during the late part of the growing season when plants are sending carbohydrates to the root system this is usually August through October.  Wait as late as possible but before the leaves start turning yellow to apply. Yearly treatments may be needed to eventually eliminate the plant entirely. Apply herbicides according to the label on the herbicide container and apply with caution as not to spray other plants. For more information on types and strengths of herbicides to use in the fight against air potato, click here. If you have questions on using herbicides contact your local county extension office.

Biological controls are being tested in various parts of Florida using a beetle that was found to dine on air potato vegetation and tubers at different life stages. For more information on biological controls, click here.

Click here for an identification card for the air potato. For more information contact the author Chris Verlide, UF/IFAS Santa Rosa County Extension – Sea Grant Extension Agent, 850-623-3868.

Air Potato can spread quickly along the ground and into trees. Photo by Julie McConnell

Air Potato can spread quickly along the ground and into trees. Photo by Julie McConnell (click for larger image)


Invasive Species of the Day (February 23): Kudzu Bugs and Beach Vitex

Invasive Species of the Day (February 23): Kudzu Bugs and Beach Vitex


Kudzu Bug (Megacopta cribraria):

Florida is extending a warm welcome to a new pest!  In 2012, the Kudzu bug made its first appearance in our state.  And they are settling in to stay.  The kudzu bug was first documented in the US in 2009 in Northeast Georgia.  It has quickly spread throughout the southeast.

At first, a pest that attacks kudzu sounds pretty good but this bug also attacks wisteria, figs, and other legumes like beans and peas.  It is a serious pest to soybeans that are grown in our area.  They are similar to stink bugs and discharge an odor when disturbed.   Skin and eye irritation can occur from this odor emission.

Kudzu bugs are small (3.5-6mm long), and are rounded oblong in shape, and olive-green in color.  They lay egg masses in two rows of 13 to 137 eggs per row.  The first generation of kudzu bugs seem to prefer to feed on kudzu but subsequent generations will feed on and lay eggs on other legumes.  When fall comes, the adults over-winter where they can find shelter.  They crawl under tree bark and into cracks in houses.


Kudzu bug feeding

Kudzu Bugs feeding on soybean plants in Jackson County. Credit: Doug Mayo

If kudzu bugs make their way into your home, you can vacuum them up and dispose of them.  If they are in your landscape or garden, you can set up a trap using a bucket of soapy water and a piece of white poster board.  Kudzu bugs are attracted to lighter colors.  To make the trap, cut the poster board in half.  Attach the two halves by cutting a line up the middle of the two pieces and put them together.  They should be in the shape of a plus sign.  Place the board over the bucket of soapy water.


Insecticides can be used but timing and placement are very important.  Right now, kudzu bugs are just becoming active making now a good time to spray kudzu host plants with an insecticide.  Insecticide active ingredients ending in “-thrin” are effective against kudzu bugs.  Controlling kudzu near your house will help decrease the number of bugs but they are strong flyers and can migrate through neighborhoods that aren’t near kudzu.

There are some natural enemies of kudzu bugs!  Generalist predators like green lacewings, lady beetles, damsel bugs and big eye bugs will attack kudzu bug nymphs.  There are also two parasitoids that attack them.  A tiny wasp was discovered in 2013 that develops in the kudzu bug eggs.  Also in 2013, a fly was discovered that lays its eggs in the adult kudzu bug.

For more information about kudzu bugs, refer to or go to

Beach Vitex (Vitex rotundifolia):

Beach vitex expands it's woody rhizomes aggressively; it can actually grow over sidewalks.

Beach vitex expands its woody rhizomes aggressively; it can actually grow over sidewalks and driveways.

Originally from the Pacific rim of Asia, Beach Vitex was brought to South Carolina to help restore dunes lost during storms.  Also known as round-leaved chaste tree and pohinahina, this low-growing shrub does very well in coastal habitats.  The plant is a small, deciduous shrub that can grow to a height of 3 feet and forms root and rhizome masses extending over 60 feet from the parent plant.  The stems are fleshy when young but become woody with age.  The leaves are simple and measure 1 – 2.5 inches in length, are ovate, and dark green on top while lower surface is light green to silver.  Locally it flowers in the spring producing beautiful purple to light blue flowers.  The fruit forms in mid-summer and are charcoal gray color.

Rapid growth and dense fruit production allows this plant to quickly dominate dune habitats, in some cases covering over 85% of the dune field and crowding out natives such as sea oats.  The plant is also known to produce its own chemical weapons to help outcompete native species. Coverage is so thick in some areas the term “beach kudzu” is now being used.  Conservation groups believe that this dense growth will negatively impact sea turtle nesting (both for egg laying adults and hatching young).  In 2009 the plant was listed on North Carolina’s Noxious Weed List and there is now a statewide task force to combat this invasive.  It was first reported in our area on Pensacola Beach.  There are 22 known properties on Pensacola Beach and it could very well be found in other panhandle locations. Just recently, beach vitex was listed with UF/IFAS as “invasive not recommended.”  If you suspect you have the plant you may contact your local Extension office for information on how to safely remove it.  For more information visit

Click Image to Download Wanted Poster. Please circulate to area residents to provide visual identification of Beach Vitex. Contact your Extension Office for control options and help reduce it’s impact on native species.

Click to download a “Wanted” Poster to share with neighbors and friends to lessen impact on our native species.

For more information, contact the author Rick O’Connor, UF/IFAS Extension Escambia County, Sea Grant/Marine Sciences Agent 850-475-5230.