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Life Beneath the Leaves with the Leaf-Footed Bugs

Life Beneath the Leaves with the Leaf-Footed Bugs

Photo Credit: Danielle S. Williams

Florida is home to at least nine species of insects from the genus Leptoglossus, some of which possess “foliaceous hind tibiae,” but only Leptoglossus phyllopus has earned the common name “leaf-footed bug.” This insect, a close relative of the stink bug, plays a fascinating yet problematic role in gardens. The nymphs are bright orange, while the adults are brown with a distinct flattened, leaf-shaped structure on their hind legs. Unfortunately, both stages of the leaf-footed bug are notorious pests, causing significant damage to buds, flowers, fruits, and seeds.

Photo Credit: Jennifer Carr

These pests feed on a wide variety of plants, including tomatoes, peaches, blueberries, beans, okra, and sunflowers. Their feeding activity can cause yellow and brown spots, misshapen fruits, and shriveled produce, depending on the severity and timing of the infestation.

In the fall, leaf-footed bugs can gather on warm windowsills or home siding. They can sometimes find openings in homes and get inside, but they don’t cause any damage indoors and don’t deposit eggs. Adult leaf-footed bugs also seek shelter in weedy areas or beneath layers of mulch and debris. They lay their eggs in neat rows on the undersides of leaves or along stems, with eggs hatching within 5 to 7 days. The nymphs then mature in approximately 25 to 30 days, leading to a rapid increase in population.

Integrated Pest Management (IPM) strategies are highly effective for controlling leaf-footed bugs. IPM involves a combination of cultural, physical/mechanical, biological, and—when necessary—chemical control methods. Following the IPM triangle approach, gardeners can start with the least harmful methods (like cultural practices) and gradually escalate to chemical controls if needed, depending on the infestation threshold. Early scouting and intervention are crucial to preventing the population from escalating throughout the growing season.

Though there are only a few organic pesticides that effectively manage leaf-footed bugs, proactive steps like hand-picking and reducing overwintering sites can help curb their numbers in the following year. For larger infestations, homeowners might consider using pyrethroids, which should be applied according to the manufacturer’s instructions. Leaf-footed bugs are also susceptible to insecticidal soaps and other pyrethroid-based products available at most garden retailers.

A word of caution: Some beneficial insects, such as assassin bugs, resemble the orange nymphs of leaf-footed bugs. Be sure to correctly identify these insects to avoid harming species that are beneficial to your garden.

For more information about leaf-footed bugs and effective control measures click on the link below or contact your local Extension office for more details.

https://edis.ifas.ufl.edu/publication/in229

The Mealybug Destroyer

The Mealybug Destroyer

Scouting is an important part of keeping pests in check and gardeners are often up to the task.  As you routinely enjoy the beauty of your ornamental and edible plants, you are likely to catch a pest sighting before it gets out of control.  One insect that may trick us upon first glance into thinking we have a pest is an interesting lady beetle called the Mealybug destroyer.

Lady beetles are one of the most recognizable insects in the garden with their rounded shiny bodies and often bright colors and spots.  The adult mealybug destroyer is smaller than a typical lady beetle, about 1/8 of an inch long, with a dark brownish black body and dull orangish head.  They move quickly over flowers and leaves in search of food. The larval stage can be confusing because immatures look very similar to mealybugs, one of their favorite prey.  Larva have white, woolly protuberances on the body.  Whereas pest mealybugs look flatter, the mealybug destroyer immatures have parts that look like soft white spikes.

Pest mealybug compared to beneficial mealybug destroyer. Photos by Beth Bolles, UF IFAS Extension Escambia County.

Why not learn to recognize an insect that eats lots of soft bodied pests on your plants? Once you see one, you will be able to spot these beneficials more often on your favorite garden flowers.

Mealybug destroyer immatures feeding on aphids. Photo by Beth Bolles, UF IFAS Extension Escambia County

Tis the Season for Plant Dieback – Here’s How to React

Tis the Season for Plant Dieback – Here’s How to React

In the last couple of weeks, I’ve had multiple questions regarding trees and shrubs that aren’t looking too hot.  These types of calls are common this time of year – it has gotten hot and dry, and plants have fully emerged from winter, causing issues that have been hiding under the surface during the dormant season to manifest as crown or branch dieback.  While there are a wide variety of things that can cause dieback, in most cases a little detective work can help pinpoint the issue.  Let’s look at a few of the most common causes of dieback and some corrective measures that may help restore the plants to health.

The first thing to do when you notice a plant in decline is nothing.  Don’t try and oversaturate it with water.  Don’t run out and dump a bunch of fertilizer around it.  Many times, these panic measures exacerbate the stress the plant is already under.  Instead, I encourage you to give us a call at your local  UF/IFAS County Extension Office.  We can likely help identify the cause of the problem through a site visit to your property or by you sending us diagnostic photos of the plant with a description of what’s been going on with it – the more information you can provide about the plant and the management practices it has experienced, the better (you can email diagnostic images/information to d.leonard@ufl.edu).

The most common cause of tree/shrub dieback that I see arises from improper planting practices.  Most landscape plants should be planted at or just above the surrounding soil level, preferably where the topmost root arises from the trunk.  To accomplish this, planting holes should be dug slightly shallower than the rootball’s height and about twice as wide.  Planting any deeper than that is probably too deep and can cause problems like trunk and root decay, which lead to crown dieback.  Unfortunately, once a plant is planted too deep, it cannot be corrected other than digging up and replanting at the proper depth, which may or may not be possible depending on the size of the tree.  Another common issue that can arise after planting is girdling roots.  This occurs when plants are grown in plastic containers and develop a root system that circles the inner wall of the pot.  If not trimmed, the plant’s root system will continue to grow in this manner, eventually encircling the plant’s trunk, cutting off water and nutrient flow, and leading to crown dieback.  Fortunately, this condition can be prevented by cutting, removing, or redirecting these roots at planting.

The next most common cause of plant dieback occurs due to soil disturbance by people.  It’s easy to forget but the root zone of trees and shrubs can reach out several times farther than the plant is tall and is easily damaged.  Disturbances to the root zone from digging or trenching near trees or compaction from prolonged vehicle travel over the area cause damage that might be slow to appear but can lead to plant decline. If you are doing construction or building near a shrub or tree, try to keep digging machinery as far out of the root zone as possible and avoid repeatedly parking or driving vehicles over the root zone area.  Like below ground root damage, trunk damage that occurs from injury by string trimmers, mowers, or animal feeding activity can all disrupt the flow of water and nutrients in plants and prove deadly.  There is no cure for this type of damage, so employing physical barriers to prevent damage is key.

The last major stress is environmental in nature and is caused by a water imbalance – either too much or not enough.  Dry soil conditions during the planting and establishment phases (first several years after planting) should obviously be avoided if possible – keeping the developing rootzone moist and allowing plant roots to establish in their native soil is critical.  Too much water can also cause problems for trees planted in poorly drained soil.  Excessive moisture leads to root diseases, which ultimately presents as dieback in the canopy.  If planting in an area that tends to stay wet, select a species of plant adapted for that sort of site – some species are more tolerant of “wet feet” than others.  While many people expect disease and insect damage to be the cause of an unhealthy plant, they’re often not the biggest culprit and, if they occur at all, are generally secondary to one of the above issues.

For more information about crown dieback or declining landscape plants, contact your local UF/IFAS County Extension office.  Happy gardening!

Mole Crickets

Mole Crickets

A mole cricket has a face only a mother could love. They are so strange looking, in fact, that in the past week I’ve had two people ask me what they were. They have large, round, helmet-like heads, undersized eyes, and massive front claws used for digging. Unlike your garden-variety crickets, which really don’t cause any major damage to home landscapes, the mole cricket is quite the turfgrass menace. Instead of hopping about aboveground, they tunnel beneath the lawn and feast on the roots and leaves of grass, often destroying entire yards. They are also vegetable pests, going after tomatoes, cabbage, and peppers.

A young mole cricket. Its round head and large front claws distinguish it from other cricket species. Photo credit: Lucy Adams Stevenson
A) Horizontal and B) vertical view of a generalized tawny mole cricket burrow showing
1) horn, 2) 1st constriction, 3) bulb, 4) 2nd constriction, 5) turn-around,
6) surface tunnel, and 7) deep tunnel. Figure 1 from Nickerson et al. 1979. Ann. Entomol. Soc. Am. 72(3):438-440.

Mole crickets spend most of their time below ground and form burrows for hiding, laying eggs, and traversing through their territory. In mating season, males create a monotone song that averages 88 decibels—as loud as a motorcycle! The call comes from their burrows, which have funnel-like openings that expand at the surface, creating amplification comparable to a horn.

Beneficial larra wasp parasitizing a tawny mole cricket. Photo credit: UF IFAS

The tawny mole cricket (Neoscapteriscus vicinus) is the most common to our area and is an invasive species from South America. UF IFAS has had a specific research program related to mole cricket management since the late 1970’s. One successful outcome of this program has been the introduction of a biological control species, the larra wasp (Larra bicolor). The wasp manages mole cricket populations by stinging and temporarily paralyzing crickets. A female will then deposit an egg into the mole cricket’s body. The cricket recovers and goes about its daily routine until the egg hatches, at which point the larval wasp feeds on and eventually kills the mole cricket. Along with the wasp and release of flies and a nematode that also manage mole crickets, the biocontrol methods introduced between the 1980’s and 2004 have resulted in a 95% reduction in mole cricket populations in north Florida.

If you are seeing mole crickets, you can attract larra wasps to your property by planting shrubby false buttonweed or partridge pea plants, which the wasps feed on. If you have serious damage from mole crickets, check out this thorough Mole Cricket Integrated Pest Management Guide, or contact the horticulture agent at your local county extension office to get a site-specific recommendation for management.

Japanese beetle – Be Aware of the Potential Threat, Stay Informed.

Japanese beetle – Be Aware of the Potential Threat, Stay Informed.

Credit: Worrel Diedrick, Florida A&M University

They are known for their voracious feeding habits, targeting a wide range of plants, including ornamentals, fruit trees, and vegetables. I speak of no other than the Japanese beetle (Popillia japonica) an invasive species in the United States, originating from Japan.  

Though reports have been made of Japanese beetle sightings in Florida, there is still not a known established population. However, it’s important to note that the status of Japanese beetles in Florida can change, potentially rapidly, over time. Thus, it is important to be able to identify the species’ host plants and damaged caused. Early detection, monitoring, and swift action can help minimize the potential damage caused by invasive species like Japanese beetles that could potentially have negative impacts on agricultural crops, gardens, and ornamental plants.

Description

The adult Japanese beetle is an attractive pest that is generally metallic green, with bronze or copper-brown wing covers that do not completely cover the abdomen, revealing five patches of white hairs on each side and one pair on the last abdominal segment. These features distinguish Popillia japonica from all other similar looking beetles. In terms of shape, Japanese beetle generally have a broad oval body structure. Notably, the female beetles tend to be larger in size compared to their male counter parts.

Developmental stages usually take place under the soil after the female deposit her eggs. In most instances they complete their life cycle in one year emerging later in the summer months, however this varies based on locations.

Host plants

Japanese beetles have known to have over 300 host plant species; however, some common host plants include maples, soybean, ornamental apple species, plums, peaches, roses, blackberry, raspberry, limes, elms, grapes, and corn. Crepe myrtle and turfgrasses are also host plants.

Damages

Both adults and larvae cause plant damage. Adults feed on the foliage of host plants resulting in skeletonization of the leaves, while larvae feed on the root systems of turf and pasture species, affecting the ability of the plant to uptake nutrient and water from the soil.

Management

If Japanese beetle populations do become established in Florida, it is generally advisable to take measures to manage the population such as physically removing them, using pheromone traps, or other integrated pest management strategies. Chemical recommendations are not currently available in Florida since this beetle is not reported as a pest problem. However, it is always advisable to contact your Local Extension office for recommendations. The United States Department of Agriculture (USDA) has also provided some useful information on the Japanese beetle in their homeowner’s handbook titled “Managing the Japanese Beetle: A Homeowners Handbook’’.

For the most current and accurate information specific to Japanese beetles in Florida management and species identification, consult your extension office. Supporting document can also be found by clicking the link below.

Useful resources: