Saddleback Caterpillar, Acharia stimulea. Image Credit Matthew Orwat

by Larry Williams, UF/IFAS Extension Agent

Did you know we have caterpillars that sting here in Northwest Florida? Well, we do and you’d be wise to learn about them and how to recognize them.

These caterpillars do not sting in the same way that a wasp or bee might sting. They do not have “stingers.” But they do have spines, also called nettling hairs, which are connected to poison glands that can inflict a painful reaction if touched.

The four nettling caterpillars that you are more likely to encounter in Florida are the hag caterpillar, Io moth caterpillar, puss caterpillar and saddleback caterpillar. Those that you are less likely to come in contact with include the buck moth caterpillar, flannel moth caterpillar, spiny oak-slug caterpillar and tussock moth caterpillar.

The “sting” is unintentional, not deliberate. When brushed against or touched, the toxin-bearing spines breakoff, releasing toxins. In some cases, broken spines pierce the skin. In other cases, toxins leak out onto the surface of the skin.

A University of Florida-IFAS Extension publication about these caterpillars states, “Some people experience severe reactions to the poison released by the spines and require medical attention. Others experience only an itching or burning sensation.”

The kind of reaction can depend on the type of caterpillar, extent of contact and susceptibility of individual. Fortunately, most of these caterpillars spend most of their time high up in trees away from us. But they can blow out of the trees during windy weather or come down still attached to branches and limbs that fall.

The saddleback caterpillar is more likely to be encountered because it feeds on many of our common landscape plants such as hibiscus and palms. But it is also know to feed on azaleas, fruit trees and even canna lilies. The saddleback caterpillar is striking in appearance with what looks like a bright green “blanket” draped over its back and a brown saddle-shaped oval area in the center of the blanket. Its spines are colorful, sharp and protrude from the front, back and sides of the caterpillar. It is stout and 1 to 1.5 inches long.

I’ve received questions about the puss caterpillar recently from people who have encountered it. This caterpillar is stout-bodied, almost 1 inch long and completely covered with gray to brown soft hairs. They seem to prefer leaves of oaks and citrus but they will feed on a variety of broadleaf trees and shrubs,

Because of their bright colors and interesting appearance, children may be tempted to touch or pick up some of these stinging caterpillars.

More information on these caterpillars is available at these websites.

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by Larry Williams, UF/IFAS Horticulture AgentYoung-Blackgum-Tree

As summer changes to fall, the shorter day length and cooler weather bring on changes in our shrubs, trees and lawns.

Evergreen plants such as azalea, gardenia, holly, camellia, cherry laurel and magnolia may lose older leaves on branches near the center of the plant during late summer through spring. There is no need for alarm by the loss of older, mature leaves during this time. This is the normal aging of older leaves.

However, be careful to not confuse this normal process with spider mites, scale, lace bugs, nutrient deficiencies, poor growing conditions, salt injury, etc. Just keep in mind that this normal change in leaf color and leaf drop occurs on the older leaves generally during cooler weather – it’s a seasonal change.

If the younger leaves, those nearest the tip of the shoot, turn yellow or brown there is cause for concern. Poor drainage, lack of water or alkaline soils may cause this condition. 

Leaves of sycamore trees change from green to brown late in the season. This phenomenon is not caused by a change in day length or temperature. It is the result of sycamore lace bugs feeding on the leaves. This will take care of itself since sycamore trees will soon be dropping their leaves.

We also have some trees that exhibit beautiful fall foliage in North Florida. A few to consider include hickory and gingko for their bright yellow fall foliage, black gum for its early display of brilliant red, purple or orange leaves and red maple or  Florida maple with their yellow or orange to scarlet red fall leaves. This seasonal change in foliage color is due to a combination of cooler temperatures and shorter days causing the green plant pigment chlorophyll to breakdown while other pigments become visible. Xanthophyll pigments result in some of the yellows, while carotenoid pigments are responsible for orange and anthocyanin pigments cause some of the red and purple colors seen in many fall leaves.

Our lawns also experience seasonal changes. Growth rate of lawn grasses decreases in fall. Not only does this slowdown in growth result in less required mowing but it also results in lawns not being as attractive as they were during spring and summer. Weak, thinning and damaged areas in the lawn will show little to no improvement during this time because of this slowdown in growth.

Some of our lawn grasses will exhibit reddish purple blades intermingled with mostly green blades throughout the lawn as a result of cool fall temperatures. Most lawns will normally turn brown with the arrival of the first killing frost in unprotected areas. 


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by Sheila Dunning, Commercial Horticulture Agent

Each fall, nature puts on a brilliant show of color throughout the United States.  As the temperatures drop, autumn encourages the “leaf peepers” to hit the road in search of the red-, yellow- and orange-colored leaves of the northern deciduous trees.  Here in the Florida Panhandle, fall color means wildflowers.  As one drives the roads it’s nearly impossible to not see the bright yellows in the ditches and along the wood’s edge.  Golden Asters (Chrysopsis spp.), Tickseeds (Coreopsis spp.), Silkgrasses (Pityopsis spp.), Sunflowers (Helianthus spp.) and Goldenrods (Solidago spp.) are displaying their petals of gold at every turn.  These wildflowers are all members of the Aster family, one of the largest plant families in the world.  For most, envisioning an Aster means a flower that looks like a daisy.  While many are daisy-like in structure, others lack the petals and appear more like cascading sprays.  So if you are one of the many “hitting the road in search of fall color”, head to open areas.  For wildflowers, that means rural locations with limited homes and businesses.  Forested areas and non-grazed pastures typically have showy displays, especially when a spring burn was performed earlier in the year.  With the drought we experienced, moist, low-lying areas will naturally be the best areas to view the many golden wildflowers.  Visit the Florida Wildflower Foundation website,, to see both what’s in bloom and the locations of the state’s prime viewing areas.  And if you are want to add native wildflowers and other Florida-friendly plants to your landscape join the Master Gardeners for their Fall Plant Sale to be held Saturday, October 14 from 8 am to noon at the Okaloosa County Extension Annex located at 127 SW Hollywood Blvd, Ft. Walton Beach.

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Fall should be our busiest gardening season in North Florida.

Many plants only do well when planted during the cooler weather of fall. Fall-planted trees and shrubs have a higher survival rate as compared to those planted in spring. Many nurseries have a better selection of trees during the cooler months. And, nurseries and garden centers could use your business this time of year.

To help prepare for the fall, I’ll provide a seminar titled “Fall: Florida’s Best Gardening Season” on Tuesday, September 5th. I’ll cover why fall is our best gardening season and encourage participants to take advantage of the season that allows Northwest Florida gardeners to get the most bang for their buck in their lawns, landscapes and gardens. This topic will include information on annuals, perennials, bulbs, vegetables, and herbs to plant during fall. Basic fall lawn care and the reason why trees and shrubs are best planted during fall and early winter will be addressed.

This seminar begins at 10:30 a.m. at the Crestview Public Library as part of their First Tuesday series. The library is located at 1445 Commerce Drive behind the post office in north Crestview.

Call the library at 682-4432 or the Okaloosa County Extension Office at 689-5850 for more information.

September’s plant clinic will be held Friday, September 8 from 9 a.m. to 12 p.m. in Fort Walton Beach at the Okaloosa County Extension building, 127 W. Hollywood Blvd.

Bring a fresh sample of the weed, plant, insect, etc., that you’d like diagnosed to the clinic. This may include a plant stem with several leaves, a 4-inch square of grass with roots attached, etc. You also may bring a sample of soil for pH testing. Here’s how to collect a soil sample.

Collect a composite soil sample by removing sub-samples from ten to fifteen small holes dug throughout the sample area (e.g. the front yard). To obtain the sub-samples, carefully pull back mulch, grass or ground covers to expose bare soil. With a hand trowel or shovel, dig small holes six inches deep and then remove a one inch thick by six inch deep slice of soil. Combine and mix the sub-samples in a clean plastic bucket. Place about two cups of this mixture in a plastic bag or small throwaway plastic container. Close the container. If the soil is wet, let it air dry by spreading it out on newspaper before putting it in the container. Make sure to attach a slip of paper with your name, phone number and where the sample was taken (e.g. lawn, vegetable garden, flowerbed, etc.).


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by Larry Williams, UF/IFAS Horticulture Agent

Symptoms of take-all root rot. Photo credit: Sheila Dunning, UF/IFAS

Take-all root rot is a disease that often affects our Florida lawns this time of year. Rainy weather can trigger this disease.

The name take-all is descriptive in that this native soil-borne fungus, Gaeumannomyces graminis var. graminis, can result in relatively large areas of a lawn dying down to bare ground. This pathogen affects all warm-season turfgrasses.

Continue reading

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Fair is a very busy time for Okaloosa County 4-H. There are just so many things to prepare for. Animals need baths, their hair and nails clipped. 4Hers are busy polishing off their skills in show and project delivery. It is the best time of year to come out and see all of what our kids have been working on all year long. 4-H youth have been raising farm animals that range from chickens and cows to other smaller animals such as rabbits and cavy. They have also been perfecting skills such as cooking, sewing, and even canning!

The best part of fair is its diversity of project areas. Local 4-H members are able to display anything from photography to robotics and show animals ranging from steer to turkeys. Throughout fair, youth will participate in competitions in which they will demonstrate their knowledge in animal science and showmanship techniques. We even have a dog show on Thursday night which includes some of the best dressed dogs around! It is a fun and eventful time. Okaloosa County Clubs will also have booths available to provide extra information about current offerings through 4-H in our area. Nightly demonstrations in the 4-H building are scheduled to give the public a small idea of what these amazing youth are learning throughout the year. So, mark your calendars and come visit us at the Northwest Florida Fair this year September 25th-30th at the Northwest Florida Fair Grounds in Ft Walton Beach Florida.

This year our fair is open to all Okaloosa, Walton, and Santa Rosa County 4-H members. If you are interested in participating in the Northwest Florida Fair, please contact the UF IFAS Okaloosa County Extension Office at 850-689-5850 or email me at for registration information. All registration is due to this office by 4:30pm on September 15th, 2017. Premium booklets and registration forms are available on our website at

The fair will be open Tuesday-Friday, September 25th-29th, from 5pm-10pm and Saturday, September 30th, from 2pm-10pm. For more information on the Northwest Florida Fair visit their website at

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Water efficient landscapes don’t happen by chance. They happen by design. The following are ideas to help in designing a more water efficient landscape. An efficient water use design includes dividing the landscape into three water-use zones: low, medium and high.

Low water-use zones require little to no supplemental water after establishment. Moderate water-use zones contain plants that require some supplemental irrigation during hot, dry periods. High water-use zones should be limited in the landscape to small high-impact or most visible areas of the home such as the entrance.

Shade helps cool the landscape by as much as twenty degrees and reduces water loss. It is an important design concept. Use practical lawn areas. Locate lawn grass where it provides the most functional benefit such as recreational areas or on slopes to prevent erosion. Separate the lawn from ornamental plants in the landscape so they can be watered separately. Most lawn grasses can be located in any of the three water-use zones but the amount and frequency of irrigation should be adjusted accordingly.

Only water plants that need to be watered. An irrigation system is a tool to supplement rainfall, not to water in addition to rainfall. Daily watering is bad for plants. It encourages shallow root systems and causes plants to demand more water. Water your lawn and landscape on an as-needed basis.

Midday watering of turf areas is not recommended because much of the applied water can be lost due to evaporation and wind blowing the water off site. Water between 9:00 p.m. and 8:00 a.m. to minimize evaporation and foliar diseases.

Consider use of micro-irrigation in plant bed, vegetable garden and fruit garden areas. Micro-irrigation uses less water and is more efficient than traditional irrigation systems.

Mulch is vital to a water-efficient landscape. Mulch helps conserve soil moisture and keeps the root area cooler during hot, dry weather. A two to three inch layer of organic mulch such as pine straw, pine bark or woodchips helps create a more water efficient landscape.

Try to match the right plant for the site conditions and preserve as many native plants as possible. Native plants are generally well adapted to the environment and may require no supplemental irrigation.

During dry weather, mow the lawn so that no more than 1/3 of the leaf height is removed at each mowing. This reduces plant stress and water demand. Reduce fertilization during dry weather because it can damage plant roots in dry soils.

For additional water saving ideas, contact the UF/IFAS Extension Office in your County (

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