by Sheila Dunning | Feb 3, 2017
Remember last summer? The hot, dry days. Grass drying up and turning brown. Yet, the weeds are green and doing fine. However, every herbicide label warns against applying when the temperatures are above 85 degrees and especially under drought conditions. Those weeds flourished and dispersed seed everywhere. Now, they are just sitting there ready to sprout again.
It’s time to start thinking about weed prevention. Pre-emergent herbicides need to be applied prior to seed germination. Late winter is the time to focus on summer annual weeds. The narrow window of application is challenging. Homeowners often wait too late into spring to put out preventative products. A general rule of thumb for pre-emergent herbicide timing is February 15 – March 1 in North Florida.
However, weed seeds germinate in response to soil temperature, not calendar dates. By monitoring day time temperatures, one can determine a more effective application date. When there are 4-5 consecutive days that reach 65 to 70 degrees weeds will germinate. This generally coincides with the first blooms appearing on azaleas and dogwood. With a warm winter it may occur as early as mid-January.
Some of the active ingredients in pre-emergent herbicides include dithiopyr, isoxaben, oryzalin, pendimethalin, prodiamine and simazine. Always read the label for specific weed controlled and observe all directions, restrictions and precautions.
Weed and feed products that contain nitrogen are not suitable as pre-emergent herbicides. Irrigation before and after application is necessary to activate these products. The chemical binds to soil particles, creating a barrier that remains effective for 6-12 weeks. Reapplication will be necessary for season long control, especially with constantly fluctuating winter temperatures. Now is the time to purchase pre-emergent herbicides and prepare to apply them. For more information on weed control in lawns go to: http://edis.ifas.ufl.edu/ep141
by Matt Lollar | Nov 7, 2016
Chinese elm tree leaves fall due to feeding squirrels. Photo Credit: University of Florida/IFAS Extension
The Chinese elms in my yard are under attack. They are dropping leaves and the temperature’s still in the 70s. Upon closer look, they aren’t just dropping leaves but the tips of branches too. What is going on? Is there a new insect pest wreaking havoc on my trees? Did I do something wrong? No, no, and…no. The culprits are tree rats! You know, those bushy-tailed rodents that live in the trees (also known as squirrels).
Squirrels feed on a number of things in my yard including mushrooms, acorns, and now I’ll have to add elm branches to the list. Chewing on branches doesn’t sound appetizing to me but, as with everything, there is a reason for it. The best explanation is that the varmints can sense an accumulation of sugars in the trees and they are feeding on the cambium layer underneath the bark.
Another explanation is that there are no other preferred food sources available. However, I can debunk that theory because the squirrels have not even touched my ripe satsumas. And we all know that satsumas taste a lot better than tree branches.
A hungry squirrel feeds on Chinese elm wood. Photo Credit: University of Florida/IFAS Extension.
Whatever the reason, the feeding may actually do a bit of good for the trees. The squirrels mainly feed on the new tree growth. This helps to promote new branching, growth which will potentially contribute to better shading from the tree. However, there is a tried-and-true solution to the problem if the squirrels annoy you as much as they annoy me. I prefer to brine squirrel in a mixture of water, salt, and sugar before I put them on the grill but you can prepare them in any way you’d like.
by Beth Bolles | Oct 7, 2016
The year’s mild winter and frequent rain showers have created lush lawns and gardens with an abundance of insects. As a result, we are seeing many predator arthropods taking advantage of the available feast. One of the morning interesting creatures in the garden is the spiny orb weaver spider (Gasteracantha cancriformis) that has an interesting body shape.
Spiny orb weavers are common spiders in landscapes that might not be noticed since they are much smaller than the Yellow garden spider (Argiope aurantia) and the Golden silk spider (Nephila clavipes). Once viewed, the spiny orb weaver will catch your attention because it’s abdomen has six ‘spines’ or points that extend out. Spiders also have a mix of yellow, white, red, or black marking on the abdomen.
Spiny orb weaver in the center of the web waiting for a meal. Photo by Beth Bolles
Although spiders are small, the webs which are common amongst shrubs, trees, and edges of woods become quite substantial in the fall. There may be up to 30 spirals that extend out with the spider situated in the center. You may unexpectedly encounter a web when walking through the garden or mowing around trees and shrubs. There is no worry if a spider accidently gets on you as bites are not common and not considered serious.
Spider working on her web. Photo by Beth Bolles
Some may refer to the spiny orb weaver as a crab spider based on its shape, but it is a web building where the true crab spiders are active hunters often found resting on flowers in order to ambush a meal.
Enjoy our fall weather and look out for this beneficial spider in your landscape.
by Matt Lollar | Sep 29, 2016
Tropical sod webworms (Herpetogramma phaeopteralis) have recently been encountered in a number of yards in the Panhandle. The worms usually feed in large groups and unfortunately, the first, and basically the only, sign of damage is often a large area of shorter grass due to their feeding. The arrival time of sod webworms is also unfortunate because they are part of a group of caterpillars that successively attack turf including fall armyworm (Spodoptera frugiperda), striped grass loopers (Mocisspp.), and the fiery skipper (Hylephila phyleus).
Sod webworm feeding damage in the turf thatch layer. Photo Credit: University of Florida/IFAS Extension.
Description
Larvae
Caterpillars are light yellow to orange with brown spots on each body segment and they have a dark, orange-brown head. They will grow to a full length of slight less than 1/2 inch.
Pupae
The reddish brown pupae are about about 1/4 inch long. The pupae are typically found in the upper thatch layer.
Pupa found in cocoon in St. Augustinegrass thatch. Photo Credit: Steven Arthurs, University of Florida/IFAS
Adults
The moths brown with splotchy wings and are about 3/4 inch wide.
Control
Sod webworms are difficult to control because of their spontaneity. However, in the lawn they hide in the thatch during the heat of the day. Over watering and fertilization can increase the amount of thatch. It is important to follow UF/IFAS guidelines for home lawn management.
The first line of defence is healthy turf. Proper fertilization, irrigation, and mowing height can decrease susceptibility of turfgrass against sod webworm. Over-fertilization is a common cause of caterpillar outbreaks in lawns. Cultural practices such as thatch removal by vertical mowing can help eliminate populations. Eggs are laid on grass blades and removal of grass clippings might also reduce populations.
Numerous chemical control options are available, but softer chemicals such as insecticides containing the bacteria Bacillus thuringiensis are recommended as a first line of defense. Insecticides should be applied in the morning or evening during feeding time. For additional control strategies and basic information please visit the UF/IFAS Sod Webworm Publication.
by Larry Williams | Sep 23, 2016
Mounds of sand made my pocket gopher along roadside. Photo Credit: Larry Williams
Pocket gopher is a furry animal known by many locals as “sandy mounder.” It was given this name because of the sandy mounds of excavated earth that the gopher pushes out of its underground burrows. The name sandy mounder, with time, became “salamander.” This animal is not a salamander at all. Salamanders are slimy amphibians shaped like lizards. Salamanders are often known as “spring lizards” in Florida.
To make this nomenclature problem more confusing, in some areas of Florida gopher means a certain burrowing tortoise – the gopher tortoise.
To simplify things keep in mind that in Florida “spring lizard” can mean “salamander” and “salamander” can mean “gopher” and “gopher” can mean “turtle.”
“Gopher” is a confusing word all over the country. Jeff Jackson, retired wildlife biologist with University of Georgia Extension says, “The Richardson’s ground squirrel of the west is called gopher. So is the thirteen lined ground squirrel of the Great Plains and Midwest. Moles are called gophers in many areas. And voles (certain short-tailed mice) are called gophers in some states.”
Jackson says there are six species of “sure enough, genuine pocket gophers in the United States.” Our pocket gopher is the Southeastern Pocket Gopher, found in north Florida, south Alabama and south Georgia.
The pocket gopher spends its time underground making tunnels and nests, eating roots and bearing and raising young. It may venture into residential areas where it can damage plants by feeding on tree and shrub roots or bulbs and tubers of various plants.
A pocket gopher can make fifty or more sandy mounds in a relatively short period of time. These mounds, which are normally four to six inches high and possibly a foot across, are what get homeowners’ attention. The mounds can “popup” overnight in lines or rows. They resemble fire ant mounds; however, they contain no ants.
The pocket gopher is a rodent that grows to about a foot long, has a short tail and weighs about half a pound. Its name comes from the large fur-lined pouches on the outside of its cheeks.
Even though they do contribute to the formation of soil and provide a food source for some predators, sometimes their damage may justify control measures.
Trapping is the most effective option. No chemical repellents are known to be effective. It’s illegal to use any poison to kill gophers. Vibrating devices have not been proven to repel gophers. A long held belief that Wrigley’s Juicy Fruit gum kills gophers by blocking their digestive system has been proven to be false.
A detailed fact sheet is available online at http://edis.ifas.ufl.edu/uw285.
by Matt Lollar | Sep 8, 2016
Plants can become distorted for a wide variety of reasons. Sometimes nutrient deficiencies or toxicities can cause plants to become distorted. Sometimes excessive amounts of water or sunlight can cause plants to become distorted. And sometimes insect feeding damage can be the culprit.
Insects can cause plant mutations by feeding alone or by vectoring disease from one plant to another. The most recent and most detrimental example of insects vectoring disease is the Asian Citrus Psyllid, which has distributed Huanglongbing, also known as citrus greening, to most of the citrus acreage in Florida and across the United States. Fortunately, the panhandle is currently free from this detrimental disorder. However, we still have a plethora of insects that distort plants by one way or another. One group of plant altering insects are commonly known as planthoppers.
Planthopper adults range in size between 1/8 to 1/4 inches long. They are slender and frequently have an angular, pointed head. Coloration depends on species, but generally planthoppers are of green, brown, or white. Immatures look similar to the adults except they are smaller and don’t have wings. Immatures typically feed on the underside of leaves, where the humidity is higher and they are more protected from predators.
Three growth stages of planthoppers. Photo Credit: UF/IFAS Extension
Planthoppers feed on plant leaves and shoots by sucking out the contents. The damage that ensues from feeding depends on the host plant and the hopper species. A few species of hoppers transmit pathogens that can alter plant growth. Usually, adult hoppers are pests only when found in high numbers.
Feeding damage from some species causes small white spots (stippling) to appear on the upper leaf surface, usually beginning near the leaf midrib. Stippled areas eventually merge together into larger whitish blotches. In some plants, feeding damage causes a drying and yellowing (or browning) of leaf tips and some planthopper species cause curling or stunting of newly formed leaves. Oftentimes, white, papery skin castings will remain from the molting process on the undersides of leaves.
Planthopper feeding damage on sweet olive. Photo Credit: UF/IFAS Extension
Planthoppers are rarely present in large enough numbers to cause significant plant damage. Fortunately, planthoppers have many natural enemies including lady beetles, lacewings, damsel bugs, and spiders. Sticky traps are recommended to help monitor planthopper populations. Planthoppers are usually attracted to yellow sticky traps that can be placed among the plant leaves. Small populations can be managed using these traps. If greater populations are present, then insecticidal soap can control young planthoppers. Make sure to spray both the top and underside of the leaves.
Planthoppers are minor pests in the landscape, but they can cause alarming mutations in plant material. Contact your local Extension Office for help with diagnosis and treatment options.
Remember last summer? The hot, dry days. Grass drying up and turning brown. Yet, the weeds are green and doing fine. However, every herbicide label warns against applying when the temperatures are above 85 degrees and especially under drought conditions. Those weeds flourished and dispersed seed everywhere. Now, they are just sitting there ready to sprout again.
