Homeowner/Property Manager

Asp caterpillar / Puss caterpillar/ Southern flannel moth

December 17, 2021 by ebrown

Article author: Wizzie Brown
Most recently reviewed by: Ballinger (Vacant) & & Pat Porter (2021)

Common Name(s): puss caterpillar, Southern flannel moth

Description

Eggs are small, elongate with rounded ends. The are laid in rows or clusters on foliage or small twigs and are covered with hairs from the female moth.

Larvae vary in size and color based upon stage/ instar. Early instars are yellow in color with spiny hairs emerging from the base of the body. Larvae change and become more hairy as the grow larger. Mature caterpillars are brown to gray in color, teardrop shaped with soft looking hairs covering the body. While the caterpillars look soft, you do NOT want to touch them as they can sting.

Pupae/ cocoons are typically found on plants, but mature larvae may wander from the host plant and onto adjacent plants or surfaces. Cocoons are spun from silk and are creamy white to light brown in color. They are flattened toward the front and have a hump towards the back. Cocoons are tough and may remain on the plant after the adult has emerged.

Adults are small, hairy moths with a 1-1.5 inch wingspan, with females being larger than males. Front wings are yellow and hind wings are creamy yellow. Bodies are covered with thick hair that looks like fur and is yellow to orange in color.

asp / puss caterpillar

Origin and Distribution

Asp caterpillars can be found from the east coast, down to Florida and west to Texas.

Habitat & Hosts

Eggs, larvae, and pupae are found on plants. Larvae feed on foliage of a variety of plants, but are commonly found on oaks.

Life Cycle

Complete life cycle: egg- larva- pupa- adult

Eggs are laid on foliage and small twigs of host plants by mated females that recently emerged from their cocoon. Eggs are laid in rows or sometimes in patches and are covered with hairs from the underside of the the female moth’s abdomen. Larvae are found on host plants where the feed on foliage. Mature larvae may wander from the host plant to adjacent plants and surfaces to pupate. There are two to three generations per year.

Management

If you live in the State of Texas, contact your local county agent or entomologist for management information. If you live outside of Texas, contact your local extension for management options.

Larvae are the damaging stage. While larvae feed on foliage of plants, usually they are not problematic for the plants they feed upon. Large populations can defoliate plants. Typically, these caterpillars are kept under control by natural enemies, such as tachinid flies or ichneumonid wasps. If a pesticide treatment is warranted, look for active ingredients such as Bacillus thuringiensis var. kurstaki or spinosad to reduce harming beneficial insect populations.

Concern for larvae is for their capability to sting. All stages of caterpillars can sting (as well as the shed exoskeletons), but severity of the sting increases as the size of the caterpillar increases. Asp caterpillars have spines that are hollow and contain venom. These spines can break off into skin and cause an immediate stinging sensation, reddening at the site and sometimes localized swelling. More severe reactions may include headache, nausea, fever, racing heartbeat, abdominal pain, seizures, or other issues.

If you are stung, remove spines with sticky tape and try alleviating symptoms by using ice packs, oral antihistamines, and topical hydrocortisone cream. If you are stung by an asp caterpillar and have a severe reaction, seek medical attention immediately.

Bugwood Images

Boxelder bugs

December 17, 2021 by ebrown

Article author: Wizzie Brown
Most recently reviewed by: Pat Porter (2021)

Common Name(s): boxelder bug

Description

Eggs are yellow when first laid, but turn red when almost ready to hatch.

Nymphs, the immature stages, of boxelder bugs are oval in shape like adults but are smaller. Nymphs are bright red and develop black markings and wings as they mature.

Adults are about 1/2 inch long and 1/3 inch wide. They are dark brownish gray to black with distinctive red to orange markings consisting of three red lines running lengthwise on the pronotum (the area behind the head). Wings are folded over the back of the body, overlapping each other. Red lines mark the lateral margins of the wings

boxelder bug adult

boxelder bug nymph

Origin and Distribution

Found in North America, typically on boxelder trees, but also can be found on maple and ash trees as well as other plants.

Habitat & Hosts

Boxelder bugs feed primarily on the seeds of female boxelder trees. Minor hosts plants (plants from which they obtain food) include apple, ash, cherry, chinaberry, grape, peach ,plum, maple and western soapberry trees. These bugs do not damage host plants. Although they suck plant juices while feeding, they are seldom abundant enough to harm trees.

In the fall, adults and nymphs leave trees where they feed and look for sheltered areas in which to spend the winter (overwinter). Although nymphs are often present in the fall, usually only adults survive the winter.

As temperatures drop, boxelder bugs move into tree holes, cracks and crevices around foundations, and walls, and door and window casings. Sometimes the bugs move indoors. Once inside, they move to warm areas of the building and eventually move toward windows or other sunny areas. Outdoors on warm winter days, boxelder bugs move from their protected areas to sun themselves and may be seen congregating on houses or buildings. They prefer buildings with southern or western exposures.

Life Cycle

Incomplete: egg- nymph- adult

Females deposit eggs in cracks and crevices of tree bark. After about two weeks, eggs hatch and nymphs develop into adults during the summer. There may be two or more generations per year in Texas; often several stages of nymphs and adults can be seen at the same time.

Management

If you live in the State of Texas, contact your local county agent or entomologist for management information. If you live outside of Texas, contact your local extension for management options.

Inspect the outside of the structure for areas that boxelder bugs may find to be a suitable overwintering location. It is preferable to inspect and take any necessary exclusionary steps before August. Preventive actions include:

Seal cracks and crevices and pipe/ wire penetrations with caulk or expanding foam.
Stuff weep holes with copper mesh or plastic screening made specifically for weep holes (kits are available).
Replace or repair any damaged window screens.
Replace any damaged weather stripping around the doors. If you can see daylight around doors when they are closed, replace weather stripping.
Install door sweeps on exterior doors and a rubber seal along the bottom of garage doors.
Repair or replace damaged screens or soffit vents in the roof and eaves area of the structure.

If possible, remove host plants, such as boxelder trees. Eliminate hiding places such as piles of rocks, boards, leaves, and general debris near the house.

If you do not wish to remove the host trees, and exclusion techniques are unsuccessful, you may need to apply an insecticide. To prevent indoor migration in the fall, treat young, exposed bugs on host trees in the spring and early summer. Applications should thoroughly cover the tree trunk, limbs, and foliage.

Sprays can also be applied to hibernation areas such as the foliage and trunks of trees, building foundations, fences, sides of houses, and other outside areas where the bugs congregate. Look for active ingredients such as neem, pyrethrins, cyfluthrin, deltamethrin, and esfenvalerate. Indoors, try vacuuming up unwanted bugs.

Bugwood Images

Opilionids

December 17, 2021 by holly.davis

Opilionid, also known as daddy longlegs or harvestman. Photo by John Jackman

Article author: Extension Entomologist at Weslaco (Vacant)
Most recently reviewed by: Sonja Swiger & Pat Porter (2020)

Common Name(s): Daddy longlegs, Harvestmen, Opiliones

Description

Opilionids, also called harvestmen or daddy longlegs, are common arachnids that are often under-appreciated, or even greatly feared. While it is true that they are related to spiders, they are in a separate Order, or taxonomic group, from spiders. There are some key differences between these two groups, listed in Table 1. Opilionids lack venom glands and fangs, thus the urban legend that they produce a deadly venom, just cannot bite is completely inaccurate.

Table 1. Differences between opiliones and spiders.

Opiliones	Spiders
Do NOT produce venom	Produce venom
Do NOT produce silk	Produce silk
2 eyes	6-8 eyes

Like other arachnids, opilionids have two-segmented bodies although there is no narrowing where these two segments join. Thus, their bodies are oval in shape, ranging in length from approximately 0.2 – 1 cm. They have four pairs of legs that may be very long and spindly, or much shorter. They also have a pair of pedipalps near their mouth they use for capturing food, feeding, and mating. They typically blend in well with their environment and may be reddish brown to grey or black in color with various markings on the legs and body.

Origin and Distribution

There are over 6,000 species of Opiliones identified worldwide and they can be found on all continents except Antarctica. Many species can be found throughout Texas, and several species are quite common in residential landscapes.

Showing several species of opilionids.

Photo by Joan Kearby Harves

Habitat & Hosts

Most species are active at night and remain sheltered under bark, mulch, rocks, and in caves or other structures during the day. They dehydrate easily thus are often found in association with moist environments. Occasionally, they can be found in large aggregations, probably to take advantage of a favorable habitat, reduce water loss, for protection from predators, or to mate.

They do not have good vision but rely largely on vibrations detected by specialized hairs on the second set of legs along with olfactory cues to navigate their environment and locate prey. Opilionids are generalist predators and/or scavengers, feeding on a wide range of live and dead soft-bodied prey including aphids, caterpillars, beetle larvae, slugs, mites, spiders, and even other opilionids. Unlike spiders that use venom to subdue prey, harvestmen grab prey and use their mouthparts (chelicerae and pedipalps) to tear apart and consume food. Some species have also been reported to feed on pollen, plant matter, and fungi.

Opilionids may deter predators by releasing repelling or irritating chemical compounds in the form of a gas or fluid. They may also exhibit a “bobbing” behavior, vibrating their bodies rapidly, making it difficult for a predator to get a good grip on them. If a predator does latch onto a leg, opilionids are capable of releasing individual legs at the joint closest to their bodies. This detached leg may continue to twitch for some time, distracting the would-be predator while they escape.

Life Cycle

Most opilionids reproduce sexually, although a few are capable of reproducing parthenogenetically (females produce offspring without mating). After mating, males often guard the female until she deposits her eggs. Females have a long ovipositor they use to place eggs singly or in groups in protected areas such as under mulch, bark, or in the soil. In some species the females may remain to guard the eggs until they hatch, while many others provide no further maternal care. Eggs hatch in about a month and the young will go through several molts before they reach the adult, sexually mature, stage. Adults may live from just a few months to a year or more. In more northern regions of Texas, they may overwinter in all life stages in protected areas such as outbuildings, under rocks, logs, etc.

Management

If you live in the State of Texas, contact your local county agent or entomologist for management information. If you live outside of Texas, contact your local extension for management options.

Opilionids are not considered a pest. Contrary to the popular urban legend, they are not one of the most venomous and deadly organisms known to mankind! They lack venom glands and fangs, making this myth completely unfounded. Therefore, if one is found in a dwelling it can safely be removed outdoors. Opilionids feed on many pest insects such as aphids and caterpillars, and “clean up” by feeding on dead organisms, so they can be considered beneficial in the landscape. However, if they become a nuisance or aggregate in significant numbers, habitat modification, including removing shady or protected areas, and drying out or exposing favorable habitats to sunlight will likely cause them to relocate.

Related Publications

Ohio’s Natural Enemies: Harvestmen (also known as daddy longlegs). Ohio State University. Available here.

Daddy Longlegs (Harvestmen). Missouri Department of Conservation. Available here.

Citations

Gardiner, M. and M. Griffith. Ohio’s Natural Enemies: Harvestmen (also known as daddy longlegs). 2016. Ohio State University Extension. Ent-68. Available here.

Pinto-da-Rocha, R., M. Glauco and G. Gonzalo. 2007. Harvestmen: The Biology of Opiliones. Harvard University Press. Boston, Massachusetts. 608 pages.

Cicada killer wasp

June 16, 2021 by p-porter

Article author: Pat Porter
Most recently reviewed by: Wizzie Brown (2021)

Common Name(s): cicada killer wasp

Description

Only the name is scary; cicada killer wasps are not a threat to people, just cicadas. In Texas we have two species of cicada killers, the eastern and the western (Sphecius speciosus and Sphecius grandis, respectively). Of these the eastern cicada killer is by far the most common. The males have a pseudo-stinger (false stinger which is an extension of the abdomen) but cannot sting, and females only sting if threatened, like when picked up with a bare hand. Cicada killers do not “attack” people; the behavior sometimes perceived as being an attack is actually the male being territorial, trying to drive an intruder away from the underground nest or a nearby female. Since males cannot sting, there is really no danger. If you have a cicada killer buzzing around you, then keep walking to remove yourself from the territory.

Cicada killer wasp

Cicada killer wasps are large, approximately 1 to 1.5 inches in length and have transparent brownish wings. The eastern cicada killer has a black body with white to yellow zig-zag stripes on the abdomen. The western cicada is more reddish-brown and also has white to yellow zig-zag stripes on the abdomen.

Unfortunately, the Asian giant hornet was found in Washington State in 2020, and its discovery was national news. This put people on guard all over the country, including in Texas, so now people are killing big cicada killer wasps out of fear they are the Asian giant hornet.

photo of a cicada killer wasp and Asian giant hornet

Cicada killer wasp (top) and Asian giant hornet (bottom). Pat Porter 2020

The Asian Giant Hornet is much larger than an eastern cicada killer, has a wide, orangish head, a black thorax and wings, and a black and orange smoothly striped abdomen. The eastern cicada killer has a black head that is smaller with respect to the body, a black thorax with brown wings, and a zig-zag pattern of yellow stripes on a black abdomen. If you see this yellow and black zig-zag pattern, the wasp is not an Asian giant hornet.

Origin and Distribution

The eastern cicada killer is found in the U.S. from South Dakota to New Mexico, south to Florida and all along the east coast. It is also found in Ontario, Canada. The western cicada killer can be found from Texas to California and northward to Nebraska and Washington State.

Habitat & Hosts

Favored nesting sites are those with light-textured soils that are well drained, and that are reasonably close to trees that will have cicadas in them. Unfortunately, this sometimes means the nesting sites are adjacent to patios or walkways, or in gardens or nearby embankments. A good nesting site might be utilized by several female cicada killers. The wasps are not social insects, like honey bees, they just share good nesting sites.

Life Cycle

Female cicada killers build nesting tunnels beneath the ground, with several branches leading off from the main tunnel. The tunnel is a “nursery” for their young. Females locate a cicada, sting it to cause paralysis, and bring it back to the tunnel. She will then drag it inside and stuff it, and perhaps one or two more, in a tunnel branch and lay an egg inside the last cicada and seals the branched tunnel. The egg will hatch in a few days, and the developing larva will consume the cicada(s) as it grows during the next two weeks. Once the larva is fully grown, it spins a silken cocoon in which it will remain until the following summer. It will then exit the cocoon, enter the pupal stage and ultimately emerge as an adult. There is one generation per year.

Management

If you live in the State of Texas, contact your local county agent or entomologist for management information. If you live outside of Texas, contact your local extension for management options.

Because they are not a threat to people, and because they are beneficial insects, there is seldom a need to manage cicada killers. On the other hand, cicadas, while they can be annoying, can also damage trees. Cicada killer wasps specialize in killing cicadas while posing almost no risk to humans.

Citations

Cicada Killer Wasps. The Smithsonian Institution. https://www.si.edu/spotlight/buginfo/cicada-killer-wasps.

Eastern Cicada Killer. Missouri Department of Conservation. https://mdc.mo.gov/discover-nature/field-guide/eastern-cicada-killer.

Cicada Killer Wasps. The University of Kentucky. https://entomology.ca.uky.edu/ef004.

Walnut caterpillar

May 20, 2021 by erfanv

Early instar walnut caterpillar. Photo Credit: Bill Ree, Texas A&M AgriLife Extension.

Article author: Tyler Mays
Most recently reviewed by: Molly Keck & Wizzie Brown (2021)

Common Name(s): Walnut caterpillar

Description

The walnut caterpillar has a wide host range of woody plants and trees such as pecan, walnut, hickory (Ree and Jungman 2015). The larvae range in color from reddish brown as young larvae to black with grayish lines and hairs as mature larvae, and can reach lengths of up to two inches when fully grown. Damage caused by young larvae is typically localized to a few branches because the larvae feed in colonies. Later instar larvae can cause more damage as they spread throughout the canopy as they venture away from each other. Larvae damage the plant by feeding on leaves, eventually consuming the entire leaf surface and leaving only the main leaf vein and petiole.

Origin and Distribution

The walnut caterpillar is native to North America and is common throughout most of the eastern United States. The walnut caterpillar can be found as far west as Kansas, Minnesota, Oklahoma, and Texas. In Texas, the walnut caterpillar is found throughout areas east of the Pecos River (Knutson and Ree 2016).

Habitat & Hosts

The walnut caterpillar has a wide host range of both shrubs and trees. The primary host for walnut caterpillar include trees in the Juglandaceae family such as butternut, hickory, pecan, and walnut including black, English, Japanese and Persian (Ree and Jungman 2015).

Life Cycle

The walnut caterpillar is in the insect order Lepidoptera, and has a complete life cycle passing through egg, larval, and pupal stages before becoming an adult. In mid to late spring, overwintering pupae emerge as adult moths. After mating, adult females lay eggs once in a mass of around 600 eggs. Egg masses are laid in a single layer on the underside of leaves. Larvae hatch from eggs in roughly 9 days and pass through five larval stages (instars) over the course of about three weeks (Ree and Jungman 2015). During the first four larval stages, larvae are a reddish-brown color and can be found feeding in clusters. When molting from the fourth instar to the fifth instar, the caterpillars move to the trunk or a main branch and molt together. Larvae in the 5th instar are black with grayish markings and long hairs. Fifth instar larvae venture out to feed on their own. In Texas, the walnut caterpillar can complete 2 to 3 generations per year depending on the number of frost-free days (Knutson and Ree 2016).

: Walnut caterpillar egg mass. Photo credit: Lacy L. Hyche, Auburn University, Bugwood.org

: Late instar walnut caterpillar larvae. Photo credit: Bill Ree, Texas A&M AgriLife Extension

: Walnut caterpillar moth. Photo credit: Bill Ree, Texas A&M AgriLife Extension

Management

If you live in the State of Texas, contact your local county agent or entomologist for management information. If you live outside of Texas, contact your local extension for management options.

In Texas, the walnut caterpillar rarely reaches levels that cause economic damage, but there have been occasional outbreaks that have caused economic loss (Knutson and Ree 2016). Typically parasitic insects, predatory insects, and arthropods like lady beetles and spiders keep populations from causing economic damage. Management of walnut caterpillars on small trees and in residential yards can be done by removing egg masses from leaves. Using insecticides to prevent economical damage on large trees and in orchards is more practical than physically removing egg masses. If you live in the state of Texas, contact your local County Agent or Entomologist for more management information. If you live outside of Texas, contact your local extension service for management options.