Unknowingly we interact with many small creatures in our everyday lives. Spiders are one of these groups that are beneficial to the function of human activity. This group receives much publicity as being dangerous to people and our pets. While there is always a possibility of being bitten and having venom injected by a few types of spiders, most all others are harmless to people. The primary benefit of spiders is their propensity for catching insects outside and in the home that are identified as harmful to people. Spiders come in all shapes and sizes with many hiding away, never to be seen by people.
Spiders are often included in the same group as insects, but this is not true. They belong in the group arachnids and are closely related to ticks, scorpions and mites. Spiders have two body sections (cephlothorax and abdomen) and have eight legs while insects have three body sections (head, thorax and abdomen). Scorpions usually remain outdoors and may be found indoors during hot dry periods. They are nocturnal hunters of pests that include roaches. None of the scorpions native to Florida are capable of providing a lethal sting, but it is painful when it occurs, leaving a sore and swollen at the sting area. I was reminded of this after stepping on one in the late evening while moving around the kitchen with no lights on. If the person that is stung has allergic reactions to bee stings, observe them and take precautionary health measures needed.
The spider is an important predator of harmful insects and can be found about any where in and around the home, in the garden, and many other places in the great outdoors. An Extension Entomologist I knew from North Carolina State University always mentioned, when presenting to Master Gardener Volunteer classes, that at almost any time given time, we are within two to three feet of a spider, with most so small we never see them. They are great at keeping the beneficial and harmful insect populations in balance in nature.
If you decide to spray to manage your spider population, keep in mind that by reducing the number of spiders in the landscape, you can create a reverse problem with harmful insect populations increasing dramatically. If big webs are a bother, simply take a broom and knock them down. They will rebuild by the next day, but you may not need to be in that area for a while. Always be careful and wear gloves when working in the garden, especially areas that are dark and covered, such as irrigation valve boxes, wood stacks, and other similar places. These are prime locations where the Black Widow or Recluse spiders may be set up, waiting to ambush roaches and other insects. If you are bitten by either seek immediate medical care.
Finally, spiders are fun to observe in nature! One of the most interesting spiders to watch is observable during fall in Florida – the Yellow Garden Spider. They build large webs and often place a zig zap signature in the middle. This large spider catches many insects in the garden and landscape. With early morning sunlight and dew hanging on the web during the fall, it makes for a beautifully create piece of art. Enjoy nature and all the creative processes that occur from a safe distance – spiders included!
Insects use pheromones to attract their mates and communicate with each other. Ants use pheromones to tell fellow ants where to find food. Aphids use pheromones to warn each other about potential predators. And all insects use pheromones to call for a mate.
So what exactly are pheromones? Pheromones are substances that are secreted by an individual and received by another individual of the same species. In humans, pheromones are most commonly found in sweat and detected by the olfactory system. Most animals have a functioning vomeronasal organ inside their noses to detect and process pheromones. However, it is debatable whether adult humans possess a functional vomeronasal organ.
Although most of us may not be able to detect insect pheromones, scientists have been able to identify and synthesize the pheromones of many economically important insects. These pheromones are impregnated on rubber and plastic dispensers and placed in different types of traps depending on the pest. The pheromone traps attract males of the target species. These traps are commonly used for monitoring, but in some cases can be utilized to disrupt mating habits which can help control some pests.
The most common pheromone trap in this part of the country is probably a boll weevil trap. Growing up, I thought they looked like little green lighthouses. These traps consist of a yellow-green cannister with an inverted funnel on top that contains the pheromone. While you may not be growing cotton in your home garden, there are some other common insect pests you may want to monitor and possibly disrupt.
Pecan nut casebearer trap with pheromone bait. Photo Credit: UGA Cooperative Extension
Pecan Nut Casebearer (PNC) – These moths are gray with a dark line of scales on their forewings. PNC moths are about 1/3 inches long. They lay their eggs on the outside of pecan husks in April/early May. Their larvae bore into the base of developing nuts and remain inside the nuts for four to five weeks to feed then pupate. A tent-type trap with pheromone can be hung in a pecan tree in April or May to help monitor for this insect. Depending on how many trees you have, multiple traps can be installed to possibly disrupt the mating cycle of this pest.
A yellow sticky trap with Asian citrus psyllids circled. Photo Credit: Matt Lollar, University of Florida/IFAS Extension – Santa Rosa County
Asian Citrus Psyllid (ACP) – These tiny insects are about the size of the tip of a pencil (about 1/8 inches long). They vector the Huanglongbing (HLB) disease also known as citrus greening. This disease blocks the nutrient uptake tissue of citrus trees and eventually kills infected trees. Traps consist of a yellow sticky card with a pheromone bait sometimes impregnated on the twist tie hanger. The citrus industry has been heavily impacted by citrus greening, so monitoring for this pest is very important.
An abundance of clearwing moths on a pheromone trap that has been pulled apart. Photo Credit: Matt Lollar, University of Florida/IFAS Extension – Santa Rosa County
Clearwing Moth – There are numerous species of clearwing moths that bore into the trunks of fruit and ornamental trees and shrubs. One of the most common is the peachtree borer. These insects don’t look like a typical moth. Instead, they resemble wasps. Tent-type pheromone traps can be used to monitor for clearwing moths and potentially disrupt their mating habits. Another common clearwing moth is the ash borer (lilac borer). As their name would suggest, these moths bore into the wood of ash trees, but they also like various Ligustrum species and olive trees.
These are just a few of the species of insects that can be monitored by pheromone traps. To help with the timing of trap dispersal and placement, you should get a grasp of concept of “Degree Days”. Degree day accumulation is used to predict important life events for particular insects such as the average egg laying date, egg hatch date, and larval development. More information on calculating degree days can be found in the article “Predicting Insect Development Using Degree Days” from the University of Kentucky. Fortunately for us, we can skip some of the math by utilizing the AgroClimate Growing Degree Days Calculator. Simply select the weather station closest to you on the provided map and a graph will appear.
Welcome to the world of symbiotic serenity, where ants and aphids work in harmony to create a thriving ecosystem. Ants farming aphids is a fascinating phenomenon in nature, where ants tend to aphids, protecting and nurturing them like precious livestock, while aphids provide the ants with a sweet and nutritious honeydew secretion.
The relationship between ants and aphids is complex and benefits both parties. Aphids, which are soft-bodied sucking insects that feed on plant sap, secreting honeydew – a sugary secretion that aphids produce as waste from their sap consumption. This sweet substance is highly attractive to ants, who actively tend to aphids in order to obtain honeydew as a food source.
One of the most fascinating aspects of ant farming aphids is the behavior exhibited by ants when caring and protecting aphids. Ants are known to carefully tend to aphids, often referred to as “herding”. In doing so, they stroke the aphids with their antennae, stimulating them to release honeydew. Ants then collect and consume this honeydew, which serves as a valuable source of nutrition for them.
Aphids also benefit from this mutualistic partnership by relying on ants for protection from predators such as ladybugs, lacewings, and other aphid predators. In the presence of ants, aphids are less likely to be attacked by natural enemies, which allows them to feed and reproduce more freely. In addition, ants can transport aphids to new feeding sites, which helps aphids access fresh sources of sap.
However, this mutualistic relationship between ants and aphids can also pose problems for gardeners and homeowners. When ants protect aphids from natural enemies, this can result in increased aphid populations and plant damage. Therefore, it is important to control ant farming of aphids in order to manage aphid infestations effectively.
There are several methods gardeners/homeowners can use to manage ant farming of aphids:
Early detection is key. Regularly check for aphids at least twice a week while plants are growing rapidly.
Utilize natural enemies of aphids such as parasitic wasps, lady beetles, lacewing larvae, soldier beetles, and syrphid fly larvae. These insects can help keep aphid populations at an acceptable threshold.
Ant management is crucial. A band of sticky material can be wrapped around the trunk to prevent ants from reaching the aphids.
Prune and dispose of infested branches.
Insecticidal soaps and oils can be used to suffocate aphids. However, these products only kill aphids on contact. Other synthetic insecticides like malathion, permethrin, etc. are alternatives that can control aphids, but they may harm natural enemies and pollinators such as bees.
*Important to note, follow all manufacturers instruction when using chemical products.
In conclusion, ants farming aphids is a captivating example of mutualistic interactions in nature and serve as a compelling reminder of the wonders and intricacies of the natural world.
While the azalea blooms are beautiful, it’s hard to remember what the leaves looked like last summer. But, if you look carefully, you may see some off-colored, bleached out leaves. Those are from a piercing-sucking insect. Its azalea lace bug, Stephanitis pyrioides. They overwinter as eggs on the underside of infested leaves or in the leaf litter or mulch under the shrub. Eggs hatch in late March and early April. The insect then passes through five nymphal instars before becoming an adult. It takes approximately one month for the insect to complete development from egg to adult and there are at least four generations per year. Valuable plants that are susceptible to lace bug damage should be inspected in the early spring for the presence of overwintering lace bug adults, eggs and newly hatched nymphs. Inspect these plants every two weeks during the growing season for developing lace bug infestations.
Damage caused by azalea lace bug, Stephanitis pyrioides (Scott), feeding. Photograph by James. L. Castner, University of Florida.
Both adults and nymphs have piercing-sucking mouthparts and remove sap as they feed from the underside of the leaf. Lace bug damage to the foliage detracts greatly from the plants’ beauty, reduces the plants’ ability to produce food, decreases plant vigor and causes the plant to be more susceptible to damage by other insects, diseases or unfavorable weather conditions. The azalea can become almost silver or bleached in appearance from the feeding lace bug damage.
Adult azalea lace bug, Stephanitis pyrioides (Scott). Photograph by Jamba Gyeltshen, University of Florida.
However, lace bugs often go undetected until the infested plants show severe damage sometime into the summer. By then several generations of lace bugs have been weakening the plant. Inspecting early in the spring and simply washing them off the underside of the leaves can help to avoid damage later and the need for pesticides.
Adult lace bugs are flattened and rectangular in shape measuring 1/8 to 1/4 inch long. The area behind the head and the wing covers form a broadened, lace-like body covering. The wings are light amber to transparent in color. Lace bugs leave behind spiny black spots of frass (excrement).
Lace bug nymphs are flat and oval in shape with spines projecting from their bodies in all directions. A lace bug nymph goes through five growth stages (instars) before becoming an adult. At each stage the nymph sheds its skin (molts) and these old skins often remain attached to the lower surface of infested leaves.
Azalea leaf with azalea lace bugs, Stephanitis pyrioides (Scott), and excrement spots. Photograph by James. L. Castner, University of Florida.
Azalea lace bug eggs are football-shaped and are transparent to cream colored. Lace bug eggs are found on the lower leaf surface, usually alongside or inserted into a leaf vein. Adult females secrete a varnish-like substance over the eggs that hardens into a scab-like protective covering. Other plant species, such as lantana and sycamore, may have similar symptoms. But, realize that lace bugs are host specific. They feed on their favorite plant and won’t go to another plant species. However, the life cycle is similar. Be sure to clean up all the damaged leaves. That’s where the eggs will remain for the winter. Start next spring egg-free.
The Multicolored Asian lady beetle (Harmonia axyridis) was introduced from Asia and intentionally and quickly established itself over the entire United States.
A Comparison
The Multicolored Asian Lady Beetle (MALB) adults can be distinguished from other lady beetle species by a pair of white, oval markings behind the head that form a black M-shaped pattern. Most adults have nineteen black spots on their forewings, but variability is common and spots may be missing. Adult MALBs consist of several color patterns (morphs), varying from solid orange to red with black spots.
This species is often mistaken for the seven spotted lady beetle (Coccinella septempunctata), which was introduced from Europe. Both species are usually found feeding on the same insect host and plants.
Photographer: James Castner, University of FloridaPhotographer: Russell F. Mizell, University of Florida
Both species tend to overwinter in large numbers. However, the Seven Spotted Lady Beetle overwinters under rocks, abandoned shrubs and forest edges. In contrast, the MALB is attracted to light and often aggregate and overwinter in dwellings, entering through cracks or crevices.
Due to the onset of winter and scarcity of food, MALB is more noticeable November to January in north Florida. As a result, they are a nuisance during the flight period, aggregating in walls and other parts of dwellings.
Once they enter your dwelling and experience warmth, they fly around and annoyance progresses. They produce a yellow, viscous, foul-smelling defensive substance when disturbed. The defensive substance usually leaves spots on furniture and the foul odor lingers in the air.
The solution
Seal building or caulked entry point to prevent infestation.
If beetles get inside your dwelling, a black light trap can be used.
Vacuum cleaners can be used to remove them, though, while effective, it will result in some spotting and foul odor.
In conclusion, though a nuisance, lady beetles are considered to be valuable natural enemies and should be tolerated and conserved when possible.
Supporting information for this article can be found in the UF/IFAS EDIS publications:
Citrus is one of the most cherished fruit trees in the Panhandle. Citrus owners are well aware that every year the main damage to their trees come from citrus leafminer (CLM). CLM is a small moth and its larvae feeds between the tissue layers of new leaf growth, causing serpentine mines to form under the leaf cuticle (Fig. 1). The feeding damage results in leaf curling and distortion, and severe infestations of CLM on young trees can retard the growth of trees. Another threat concerning CLM in Florida is that the mines provide an open wound for citrus canker to enter, a bacterial disease that has been found recently in the Florida Panhandle, Georgia, and Alabama.
Most commercial growers deal with CLM in young trees by a soil application of systemic insecticide before the flush season, followed by a foliar insecticide when the systemic drench’s toxicity is declining. Homeowners, however, have limited access to these chemistries. Garden systemic insecticides that include imidacloprid (Bayer’s Tree & Shrub Insect Control™, Merit®, etc.) and dinotefuran (Greenlight Tree and Shrub Insect Control™, Safari®, etc.) are among the few options for CLM control. For the best efficacy, those insecticides should be applied two weeks before the start of the flushing season to allow time for the insecticide to move from the roots into the canopy. To avoid leaching of insecticide away from the root zone, soil applications should be made within a 24-hour period without rain. Citrus trees usually have several flushes per year, depending upon cultivar, climate, and crop load. However, in the Florida Panhandle, most citrus cultivars have two major flushes in May and September.
Importantly, systemic insecticides are only efficient against CLM for small immature trees; therefore, the only products labeled for use against CLM on mature trees are foliar sprays. Horticultural oils or insecticides with spinosad (such as Monterey® Garden Insect Spray) are some options available for homeowners. However, achieving leafminer control with foliar applications on mature trees is challenging due to unsynchronized flushing of trees. Foliar applications should be timed with the appearance of the first visible leaf mines. In any case, be sure to READ THE LABEL and follow all the label directions.
Cultural practices, and non-insecticidal methods.
For isolated trees in a backyard, cultural practices and control through mass trapping are usually sufficient to control CLM and insecticide use is not recommended, especially for mature trees. One of the basic cultural practices is to remove any stems that grow below the bud union or from the rootstock, also called ‘suckers’ (Fig. 2). Those rootstock shoots compete with the scion shoots and are great reservoirs for CLM; removing them will help reducing CLM population. On isolated trees, mass trapping using CLM pheromone provide good results (Fig. 3). The mass trapping method is constituted of a delta trap baited with a lure that emits a large quantity of CLM sex pheromone. CLM males are attracted by the odor and are captured in the delta trap’s sticky liner. Those traps are commonly used by growers to monitor CLM populations, but for homeowners they are sufficient to control CLM on a single tree. This trap and a lure method should protect a single tree for approximately 3 months. Finally, the last option is the use of biological control. Several natural enemies are predators or parasitize CLM. In some case, biological control can reduce CLM populations by 90%. Primary predators of CLM include ants, lacewings, and spiders, as well as a parasitic wasp, Ageniaspis citricola that was introduced into Florida and has become established (Fig. 4).
New growth from the rootstock (called ‘suckers’, red arrow) are a source for CLM infestation and should be removed.
Baited pheromone trap for citrus leafminer (picture Danielle Sprague).
