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Beetles to the Rescue

Air-potato-with-bulbil-inset_largeAir potato (Dioscores bulbifera) is a perennial, herbaceous self-twining vine that can grow over 60 feet in length, enabling it to climb over and smother many native plants. The Florida Exotic Plant Pest Council (FLEPPC) lists air potato as a Category 1 invasive plant, which means that it has disrupted natural communities and ecological functions by displacing native plant species.

In 2012, a leaf feeding beetle (Lilioceris cheni) was introduced into South Florida from China for biological control of air potato. Although it is too early to determine any potential long-term impacts, the initial results have been promising. The larvae and adults of the air potato leaf beetle feed on the leaf tissue and occasionally the bulbils. The damage to the growing tips of the plant have dramatically reduced its ability to cover native vegetation. Extensive damage to air potato was evident within three months after the first release. Additionally, testing by scientists at the USDA/ARS Invasive Plant Research Laboratory in Fort Lauderdale concluded that the beetle will not complete development on any other plant found in Florida.air_potato_leaf_beetle09

airpotatobeetleThe female air potato leaf beetle lays an average of 1,200 eggs, which develop into larvae in about four days. The young beetles skeletonize the air potato leaves for the next eight days and then pupate into foam-like cocoons. Clumps of cocoons fall to the ground and the adult beetles emerge 13 to 16 days later. There can be a new generation of air potato leaf beetle every month while the weather is warm. For the winter, the adults hide in leaf litter and wait for spring.

 

The question now is: “How well will they survive through a longer, colder Northwest Florida winter?”. USDA scientists, UF Extension agents and citizen scientists in Bay and Okaloosa County hope to find out. Earlier this month, June 2015, air potato leaf beetles from the Hayslip Biological Control and Research and Containment Laboratory in Ft. Pierce were released into areas containing air potato. They will be monitored over the next year. Look for an update next summer.

Monitor for Mole Crickets

Monitor for Mole Crickets

Mole cricket tunnels. Credit: N. Leppla, UF/IFAS

Mole cricket tunnels. Credit: N. Leppla, UF/IFAS

Many people treat their lawn with an insecticide when they see mole crickets in the spring or at the first sign of a brown area in their lawn. What they don’t understand is the biology of this pest. 

Mole crickets spend the winter as adults in the soil. As temperatures warm in late February and March, adult mole crickets emerge and begin to mate. Male mole crickets construct a chamber in the soil and chirp to attract female crickets. Attracted females fly to the males. After mating, males die and females fly to a suitable area for egg laying. Mated females begin tunneling and laying eggs in the tunnels. They lay about four clutches of eggs in different areas, averaging 35 eggs per clutch. Female crickets die shortly after laying their eggs.  

Use of insecticides during early spring is not recommended because:

  • adult mole crickets are not easily killed
  • they cause minimal lawn damage during the mating and egg laying process, and,
  • reinfestation from subsequent flights is likely.  

The best time to treat for mole crickets is during mid-June through July. This will be when eggs have hatched but before the nymphs (immature mole crickets) are large enough to do much damage. Proper timing of the insecticide application is very important to achieve control.

Mole cricket nymphs. Credit: J. Castner, UF/IFAS

Mole cricket nymphs. Credit: J. Castner, UF/IFAS

 

If you are not sure if mole crickets are present, you can find out with a soap solution. Mix 1½ fluid ounces of a lemon scented liquid dishwashing soap in two gallons of water in a sprinkling can or bucket. Pour the soapy water over an area approximately four square feet and count the number of mole crickets that emerge. If they are present, it only takes several minutes for mole crickets to crawl to the surface after the soap treatment. Repeat the process around the yard where you suspect mole cricket problems. If you flush an average of two to four crickets per site, treat the lawn with an insecticide. Follow up with spot treatments if any crickets escape the first insecticide treatment. But don’t treat at all if there is no evidence of mole cricket activity.  

There are a number of products for mole cricket control in home lawns. Look for insecticides that contain the following active ingredients: bifenthrin, carbaryl, cyfluthrin, deltamethrin, imidacloprid , lambda-cyhalothrin or permethrin.  

Before using any product for mole cricket control first identify the problem as mole cricket damage by using the soap flush technique. Then choose an insecticide that lists mole crickets on its label. And finally, read the container carefully for use directions, application techniques, irrigation requirements and precautions.

 

Just Say No to Chinese Wisteria

Just Say No to Chinese Wisteria

chinese wisteriaMaybe you have been seeing the Chinese wisteria, Wisteria chinensis, sporting its lavender blooms along the roadways this time of year. This vine may add a pleasant splash of color to the green leafy backdrop, but this is an invasive vine that has escaped our yards and gardens and is spreading on its own in natural communities.

The University of Florida Assessment of Invasive Plants determined that this vine has caused long-term alterations in ecosystem processes and displaces native vegetation. According to the non-profit Florida Exotic Pest Plant Council (FLEPPC), Chinese wisteria is a category II invasive which means that the species has escaped cultivation and is spreading on its own into other unintended areas.

wisteria_frutescens_native

American Wisteria ‘Amethyst Falls’ at GCREC Teaching Gardens. Photo credit: UF/IFAS Extension.

Fortunately, there are several great alternatives to Chinese wisteria. A native vine, American wisteria, Wisteria frutescens,  is a great alternative. The native cultivar ‘Amethyst Falls’  displays lovely fragrant lavender blooms in the spring and summer.

Evergreen Wisteria at the GCREC Teaching Garden. Photo credit: UF/IFAS Extension.

Evergreen Wisteria at the GCREC Teaching Garden. Photo credit: UF/IFAS Extension.

Another alternative is evergreen wisteria, Millettia reticulata, a twining vine (the stems twist around upright supports) that is semi-evergreen in the Florida panhandle. The deep mauve blooms appear throughout the summer months and persist often into the autumn.

So how do you get rid of the invasive Chinese wisteria? The vine can be severed at ground level and the stump immediately treated with a 25% solution of triclopyr or glysophate. There may be some resprouting of the vine from unaffected roots that would require retreating. Please click here for more details. The best time to control this vine is in the spring or summer when it is actively growing so that it will transport the herbicide to the roots and kill the plant.

For further information:

UF/IFAS Center for Aquatic and Invasive Plants: Chinese Wisteria

UF/IFAS Assessment of Invasive Plants: Chinese Wisteria

FLEPPC: 2013 List of Invasive Plants

UF/IFAS Gardening Solutions: American Wisteria ‘Amethyst Falls’

UF/IFAS Gardening Solutions: Evergreen Wisteria

Chinese Privet

Chinese Privet

The Chinese privet, Ligustrum sinense, is a plant that is well known to many people as a great nuisance in the landscape. It is also a Florida noxious weed because of its invasive nature.

Originally grown as an ornamental that formed a hedge and tolerated poor conditions, the Chinese privet has now spread to natural areas and grows easily on disturbed soils. Plants are full of white fragrant flowers in the spring with abundant small black fruit forming late summer and remaining into the winter. Seeds are easily spread by wildlife to new areas but new plants can also grow from roots.

privet

Privet may be best identified when it is in bloom.

Chinese privet easily forms a thicket, shading areas and impacting the growth of native plants. Homeowners can identify any plants growing on their property and work to manage Chinese privet when plants are not in seed. If you need assistance in identification, contact your local Extension office or view pictures online.

Even though homeowners will not find Ligustrum sinense in the nursery, cultivars of this plant may be found. One newer selection is ‘Sunshine’. This is a reportedly sterile cultivar that grows much smaller and has yellow foliage. Homeowners who choose to install ‘Sunshine’ may still need to be cautious since there has not been extensive research in Florida to verify that it will not become a future issue.

 

Armadillos: Midnight Lawn Marauders

Appearing clumsy and bumbling at first glance, these exotic invaders quickly damage landscapes in search of tasty insects.

Appearing clumsy and bumbling at first glance, these exotic invaders quickly damage landscapes in search of tasty insects.

It can be pretty discouraging to step out one morning to find a lawn pock-marked like the lunar surface. Stunned surprise then anger is usually the owner’s response.

The offender is not the neighborhood teenager with a reputation for inappropriate practical jokes. The offender is most likely an armadillo, sometimes identified as a Florida-speed-bump or a Possum-on-the-half-shell.

Armadillos eat mostly adult insects and their larvae. They incessantly dig holes in lawns and landscapes in their search for food, many times uprooting plants and turf in their food search. Their holes are approximately one to three inches deep and three to five inches wide.

Using insecticides to decrease the armadillo food supply is not guaranteed, but may help reduce the digging. In cases where there is a large, and always ravenous, armadillo population this reduction of food may increase digging activity as they search more diligently for a smaller food supply.

Another consideration is all chemical treatments have to be re-applied on a permanent basis for impact. Always read and follow label instructions for safe use of insecticides.
To add insult to landscape injury, armadillos burrow under driveways, foundations and patios potentially causing structural damage. Additionally, their burrows in pastures pose a potential leg-injury hazard to livestock.

Burrows openings are approximately seven to eight inches in diameter, about the size of a one-gallon plastic jug, and up to 15 feet in length. The sandy soil is piled up right outside the burrow entrance. Armadillos usually rest in a deep burrow during the day and are most active after dark.

Because armadillos are nocturnal, trapping techniques designed to capture them as they emerge from their burrows should be applied late in the afternoon and checked several hours after darkness. Fencing is another potential option to discourage the presence of armadillos.

Several live-trapping techniques can be used to capture armadillos as they exit of their burrows. One method is to firmly insert a six-inch diameter PVC pipe into the entrance of an active burrow. Adult armadillos will get stuck in the pipe as they try to exit. Another option involves a nylon throw-net staked down to cover the burrow entrance. Armadillos will get tangled in the net as they emerge.

Some can be discouraged from returning to their burrows by filling the hole with a mixture of dirt and mothballs after they have departed for a night of foraging. Laying chicken-wire along a patio, driveway or house foundation will discourage burrowing.

Armadillos can also be trapped using a raccoon-size metal trap, available from local pest control, feed and home improvement stores. These animals are more likely to enter a cage trap with leaf litter or soil placed over the wire bottom.

Suggested baits for the trap are live earthworms or meal worms in surrounding soil placed in hanging bags made of old nylon stockings. Overripe or spoiled fruit which will attract insects may be used as bait. Poison baits are illegal and no chemical repellents or fumigants are registered for use in Florida.

Relocating problem animals is not recommended because it only transfers the problem elsewhere and can spread disease.

To learn more about controlling armadillos contact your local UF/IFAS Extension Office or read Baiting the Nine-banded Armadillo at http://edis.ifas.ufl.edu/uw362

Invasive or Just Great Fall Color

Invasive or Just Great Fall Color

Fall color of Chinese tallow

Fall color of Chinese tallow. Image credit UGA Extension

Chinese tallow tree (Sapium sebiferum (L.) a  deciduous and very aggressive tree. Many people appreciate the fact that it grows fast, provides great shade, and has a beautiful reddish fall color.

Despite it’s attributes, it is highly invasive and considered a noxious weed. It has spread to every coastal state from North Carolina to Texas, and inland to Arkansas. In Florida it occurs as far south as Tampa. Chinese tallow was listed in Florida as a noxious weed in 1998 which means that possession with the intent to sell, transport, or plant is illegal in the State of Florida.

The Chinese tallow tree can reach heights of 30 feet and the seeds resemble popcorn, hence its other name, popcorn tree. These popcorn shaped seeds and the aggressive root system sprouts make it very hard to control the spread of this tree. Animals also spread the seeds freely!

Although the Chinese tallow has great fall color problems come with it.

Some questions to ask yourself:

  • Do you want great fall color and a yard full of Chinese tallow?
  • Hey what about the neighbor. Do they want Chinese tallow in their yard?

Think about more than fall when planting.
To read more on how to control Chinese tallow follow this link: edis.ifas.ufl.edu/FR251