Boxelder Bugs
Boisea trivittata (Say)
Boxelder Bugs Identification
Pest Stats
Color
Black with reddish or orange markings on dorsum
Shape
Elongate-oval, somewhat flattened with head narrower than pronotum
What Do Boxelder Bugs Look Like?
Boxelder bugs are black with reddish or orange markings on their back. Adult boxelder bugs have a body shape that is a somewhat-flattened and elongated oval and is about half an inch long. They have six legs and two antennae that are typically half of their body length. Nymphs look similar to adults but lack wings and are bright red in color.
Signs of an Infestation
Boxelder bugs generally become a problem when they invade homes, sheds and garages in the fall and when they emerge in the spring. Like many overwintering pests, homeowners may see evidence of these bugs as the winter ends and they leave their overwintering site to go back outdoors.
Boxelder Bugs Prevention
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Do Boxelder Bugs Bite?
Boxelder bugs are not known to bite, but their piercing-sucking mouthparts can occasionally puncture skin, causing a slight irritation and producing a red spot similar to a mosquito bite.
Boxelder Bugs Education
Habits
Overwintering adult boxelder bugs emerge from hibernation in late March to early April when the boxelder buds open. During this time, the adults leave their overwintering sites to return to their host trees for the warmer months. They first feed on fallen boxelder seeds and later move to the female boxelder trees or maple trees where they eat newly developing leaves. Occasionally, boxelder bugs will feed on the fruits of plum and apple trees.
The females lay clusters of straw-yellow eggs on stones, eaves, grass, shrubs and trees – especially in the bark crevices of boxelder trees. The eggs turn red as the embryos develop and hatch about two weeks later. The nymphs feed on fallen boxelder seeds and later on new leaves. There are two generations per year in the warmer regions of the United States.
In the fall, boxelder bugs become gregarious and congregate on the south side of rocks, trees and buildings where the sun hits. After large masses gather, they migrate to nearby buildings or homes to overwinter. These pests tend to hide in small cracks and crevices in walls to insulate themselves from the cold winter temperatures.
Threats
Inside, boxelder bugs are primarily a nuisance pest, however their fecal material can cause a red stain on curtains, drapes, clothing, etc. When crushed or handled roughly, boxelder bugs can also produce a strong, disagreeable odor.
Habitat
In autumn, boxelder bugs become gregarious and congregate on the south side of rocks, trees and buildings where the sun hits. After large masses gather, they migrate to nearby buildings or homes to overwinter. These pests tend to hide in small cracks and crevices in walls to insulate themselves from the cold winter temperatures. In late March to early April, adults leave their overwintering sites to return to their host trees for the warmer months.
Boxelder bugs are not known to bite, but their piercing-sucking mouthparts can occasionally puncture skin, causing a slight irritation and producing a red spot similar to a mosquito bite. When crushed or handled roughly, boxelder bugs may leave a reddish orange stain from their fecal material that can result in discoloration of curtains, drapes, clothing, etc.
By Peter L. Warren Special to the Arizona Daily Star
Q: What is this tiny black beetle with orange spots? There are a bunch of tiny black beetles with orange spots in our kitchen pantry.
A: Those are carpet beetles and their larvae you will recognize as tiny, hairy grubs. Often what are found are the cast skins of the larvae from their molts among your damaged things. They are common indoor pests of stored products and other organic materials. Back in the day, when most carpets were made of wool or other natural fibers, these insects got their name. They can be found on a variety of things besides carpets and are most likely infesting something near where you are seeing them in the pantry. These insects are sometimes used by mammalogists to clean animal skeletons in scientific collections. Sadly, they are also a serious museum pest and are notorious for eating insect collections and other dead animals. In your situation, the first things to check are any open containers of pet food, bird seed, etc. Then start working through things stored in cardboard boxes or other easily chewed containers. You might also check if you have any boxes or clothing made of natural materials. The eradication of these beetles is difficult. Sanitation and exclusion are the most important tactics.
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Q: I would like to take better advantage of solar power in my garden. What ways are there to do this?
A: There are a few ways that are fairly easy to get started and then if you want to dig deeper, so to speak, you can explore other ways. To start, you might consider preserving your garden produce by dehydrating it in a solar dehydrator. These can be made fairly easily and there are plans to be found on the Internet. You can also use solar irrigation controllers in a garden drip system. If you are interested in more details and possibly some other energy-saving options, there is an Energy Masters course being offered this fall at the Campus Agricultural Center. This course will teach folks how solar PV, hot water and space heating technology work; costs and benefits of off-grid and hybrid PV systems; how to size solar PV for on and off-grid systems and solar hot water systems; local, state, and federal incentives for systems; and lastly, financing options for renewable energy. You can search the Internet for “2015 Arizona Energy Masters Course” for more details.
Q: My pyracantha leaves recently started looking like the attached picture. A drip system waters it every three days for 30 minutes. Hasn’t had a fertilizer application since Memorial Day.
A: What you are seeing is salt damage. Salts build up in the root zone from our salty water and from fertilizers. The solution is first to overwater to flush the salt through the root zone and then change your irrigation schedule to water less often but deeper. For non-desert shrubs like pyracantha it is best to water every seven to 10 days to a depth of 24 to 36 inches in the summer, every 10 to 14 days in the spring and fall, and every 14 to 21 days in the winter.
Q: I’ve been noticing the sycamore trees around where I live look pretty awful. The leaves are pale and curled up. What is causing this problem?
A: The local trees in Tucson are being eaten by the sycamore lace bug (Corythucha ciliata), a native insect, and present across North America. Sycamore lace bugs cause damage to leaves on sycamores as well as London plane trees. These lace bugs are white in color, about 1/8 inch in size, and feed on the underside of leaves on host trees. Adult lace bugs tend to have an almost see-through appearance, which, combined with venation on wings and ridges on their bodies, lends them their common name. The nymphs differ in appearance from the adults in that they are black and spiny. Adults are very mobile and their movement is aided by wind. Lace bugs go through five life stages: egg, three immature or nymph stages, and adult. Adults overwinter in bark crevices or branch junctures, and become active again in the spring when leaves begin to break from their buds. Shortly thereafter, the adults lay eggs on the underside of leaves and eggs hatch within a matter of days of being laid. Nymphs feed on the underside of the leaves as they grow. Nymphs, which are wingless, smaller, and more rounded in shape, tend to cluster together on the underside of infested leaves. Wherever they are feeding, frass (insect feces) may be seen as well. The frass appears as tiny drops, shiny and dark in color. The life cycle is about 45 days in length, allowing for several generations throughout the year.
Early infestations are evident when white spotting begins to occur on leaves where the insects are feeding. Black spots, the frass of the insects, appear widely across the underside of the leaves as well. Heavy infestations can result in bronzing and drying of leaves. Eventually, those leaves will fall prematurely, making trees look to be in poor health. Established trees can sustain this damage for several seasons. Young or newly planted trees experience more adverse effects during infestations than established trees. The damage is more severe as weather patterns bring drier conditions.
Though there are insecticides and other types of management actions that can be taken, most damage is aesthetic. Watering trees properly can help relieve stress on trees. Additionally, strong streams of water on leaves can be effective in removing insects, especially when targeting lace bugs in the nymph stage, before severe damage occurs. However, these infestations do not require any treatment. There are also natural fungi as well as predators and parasites of lace bugs that can help manage populations.
Peter L. Warren is the urban horticulture agent for the Pima County Cooperative Extension and the University of Arizona. Questions may be emailed to .
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