Friday, April 29, 2011

Watch Out for Assassin Bugs!

By Jane Morse, UF/IFAS Extension Agent, Pinellas County Extension

These bugs are meat-eating hunters! They are very beneficial in the landscape/garden as they prey (feed) on a wide variety of pest insects such as caterpillars, stinkbugs, aphids, and beetles. However, they are general predators and may also feed on each other and other beneficial insects. Since assassin bugs (also known as wheel bugs) are also preyed upon they have developed a unique defense system, they use their beak to squirt venom at their attacker as far as a foot away!

Assassin bug nymph
Assassin nymphs (young) are abundant this year. Several specimens have been brought into the Pinellas County Extension Service’s Lawn and Garden Help Desk for identification.

They come in many shapes and sizes as there are over 3,000 species. Their length can vary from less than ¼ inch to 1 ½ inches, and they have only one generation per year. ALL assassin bugs have a powerful, curved beak that they use to pierce and inject dissolving venom into their prey. Once the inside of the prey is turned to liquid, the assassin bug uses its beak to suck out the liquefied tissues, much like we use a straw to drink a milkshake!

This powerful beak packs a mean wallop, so be careful when working in the landscape/garden. When disturbed the wheel bug can inflict a bite described as worse than stings from bees, wasps, or hornets.
Remember they are doing free pest control in your landscape/garden, so it is very good to have them around. If you see them it is best to leave them alone, but you may want to watch them hunt for other bugs to eat. The landscape/garden can be a fascinating place to watch insects in action.

Avoid blanket spraying of insecticides and instead only spot-treat plants. Try using horticultural oils and insecticidal soaps rather than the more toxic insecticides. This will help to preserve these and other beneficial insects that are doing free pest control for you.

Click here to learn more about the assassin (wheel) bug.

Saturday, April 23, 2011

What will You be doing 10 years from Now?

A planning process that will shape Extension programs in Florida for the next decade has begun.

This is a joint effort between the University of Florida (UF) and the Florida Agricultural and Mechanical University (FAMU) that will allow us to have a clear path of action as an educational organization. Our goal is to create a strategic plan that will support Florida's economy, environment, and people. We want it to be relevant today and flexible enough to meet the needs of Florida's communities as they change.
Listening is at the core of Extension's long range planning effort. One way we can hear your ideas is by having you take a survey.

So please spend your next 10 minutes completing this survey. When you are done, take a minute more and share this blog with others who may be interested in contributing ideas about the future of Extension.

Mary Campbell
County Extension Director
UF/IFAS Pinellas County Extension

Friday, April 22, 2011

Those Mysterious Molds, Part 1: "The Blob"

This week's blog was written by guest blogger Dustin H. Purcell, MS. Dustin is a Mycologist/Plant Pathologist who studied at the University of Florida. 

"The Dog Vomit Fungus” aka “The Blob”

Accurate identification of fungi normally requires a microscope, experience, and some obscure resources, but this one is fairly distinctive and has no real look-alikes. It is also pretty common in our area, so most people who spend some time in the yard have wondered what it is.

It isn’t truly a fungus, but it’s fungus-like enough that mycologists (scientists who study mushrooms and other fungi) study it. Technically it is a Myxomycete, or plasmodial slime mold, named Fuligo septica. It looks kind of like that expanding foam used to fill cracks and gaps in walls around the house and garage. It has no definite shape, just a small irregular mound less than an inch in height and anywhere from around an inch to over a foot in diameter (if an irregular shape is allowed to have a diameter). Unlike expanding foam, it has a crusty-flaky coating instead of a smooth firm “skin”. If you scrape the yellowish-tan coating away (you can use your finger, but a stick will work if the that sounds too gross), you’ll see the purplish-brown spore mass inside. Spores are like seeds… They are the way myxomycetes reproduce and spread from place to place. When mature, it is completely dry and will disintegrate into an airborne cloud of spores under foot or lawnmower. Before it matures, it looks like a slimy-gooey-frothy yellowish-brownish-greenish blob.  

The dog vomit “fungus” (Fuligo septica) in its natural habitat… your yard. The specimen at the upper left is not yet mature. It is still a gooey blob that will probably dry into a crusty-powdery mass by the end of the day. On the upper right is a collection of three mature myxomycetes that have migrated up plant stems in order to produce spores. This will not harm the plant! Wind, rain and sprinklers will wash it away. The photo below this shows an individual about 5 inches long sitting on the mulch of a garden bed.  On the lower left is a large specimen (over a foot long!) following a good rain that washed away the yellow crusty coating to expose its purple-black spores.

They are common following rains or irrigation during the warmer months anywhere there is ample organic matter. This includes lawns, mulched areas, compost piles, bare soil, tree stumps and old logs. Sometimes they even “climb” a few inches up walls or the base of plants. They are not known to be harmful at all to plants or animals (including humans). Before coming to the soil surface to scare and gross out humans, they migrate through the soil as large amoebae (called plasmodia) ingesting tiny bits of decaying debris, bacteria and other microorganisms. They are not associated with any plant disease. Rather, they are an important component of the soil ecosystem and indicate that there is a decent amount of moisture and organic matter in the soil. This is a good thing, because landscape plants normally do well in soil with ample moisture and organic matter. Undisturbed, they can last for weeks in the yard until a good rain washes the spores back into the soil. Animals, including curious children armed with sticks and lawn men with lawnmowers, will also hasten the weathering process by scattering their spores to the wind.

So try not to be repulsed the next time you spot these unsightly creatures in your yard. They are probably helping your landscape, and at the very least they are doing no harm.

Friday, April 8, 2011

Oak Leaf Blister

It’s that time of year again, the leaves are green, the flowers are blooming, the birds are singing, the oak leaves are blistering. Ah spring! Wait a minute- oak leaves blistering? Yes, this is a common sight this time of year. Oak leaf blister is a common leaf disease on oaks in Florida. It can affect any oak but it seems more prevalent on laurel oak. This disease is more prominent after a cool wet weather, so we can expect to see a lot of oak leaf blister this spring. The spores of this fungus infect newer leaves and cause swollen blister-like tissue like you see in this photo (courtesy Okeechobee County Extension):

Oak leaf blister can also cause leaf distortion and leaf curl. In most cases this is just a cosmetic problem and rarely does any significant damage to an oak. This fungus only attacks the leaves and will not cause harm to the rest of the tree. In some extreme cases on a younger tree you may experience a large leaf loss. If that is the case you should rake up the fallen infected leaves and dispose of them to avoid spreading the fungal spores to your other trees. Otherwise, enjoy the shade of your oak and get some gardening done before it gets too hot!