Sunday, August 22, 2021

Orange-tipped Leaf-Footed Bug

Nothing is more frustrating to a gardener than to discover a 6-legged invader has been dining on your prized produce. Those of us who have grown squash, melons or cucumbers have had the unfortunate experience of battling the leaf-footed bug (Acanthocephala terminalis) or as it is more widely known the squash bug. This true bug in the order Hemiptera has a piercing, sucking mouthpart called a proboscis that it uses to puncture the stems of plants to reach the more tender tissue underneath.

It will inject an enzyme into the plant which begins dissolving the tissue into something the bug can slurp up through their proboscis, much like we suck through a straw. They cannot digest solid food.  In most cases this does not harm the plant, but if you have numerous squash bugs present on your plants, it may mean the plants cannot produce sufficient fruit. These opportunistic feeders are known to feed on a wide variety of garden plants as well as blackberries, hickories, goldenrod, Joe-pye weed and other shrubs.  They have also been observed probing their mouths into bird droppings. It is not fully understood why they do this or if they even consume any part of the droppings. One could assume, like many other species of insects that do feed on these droppings, that they gain some level of mineral benefits. If this is the case, it would mean they do indeed feed on the droppings and aren’t just inserting their proboscis into the waste of our avian friends for the fun of it.

The name leaf-footed bug comes from the swollen leaf-like midsection of the hindlegs. All leaf-footed bugs have four segmented antennae, and this species is one of the largest found in the Eastern United States and may reach lengths up to one inch. They are typically black but may also be dark brown.

These insects aren’t known to bite, but they would have the mouthpart for such a defense if needed. However, their main defense is a chemical one. If severely disturbed, they will emit a foul-smelling secretion that has earned them another common name of stinkbug. The stinkbugs we are all familiar with are also true bugs in the same order as the squash bug, but they are not closely related, even though they share the same ability to release a nasty chemical defense to protect themselves. These bugs are easily disturbed and will readily fly away with a loud buzzing noise and land several yards away. They usually hide out among the plants they feed on or in the leaf-litter below the plants. The nymphs hide out under the leaves, out of sight of the prying eyes of potential predators. The adults are often spotted on the leaves out in the open. Get too close and they rapidly fly away.

After mating, the females will lay white eggs on the leaves of the host plant. The tiny nymphs hatch in several days and begin feeding. They must go through five instars (molts) before reaching their adult size. There is only one generation per season and the adults spend the winter in leaf litter or under the bark of trees. When spring returns the cycle will start all over again.

How does one protect their gardens from such an unwanted visitor? I am not a huge advocate for insecticides simply because they do not just kill or remove your target insect. They also destroy beneficial insects which can be counterproductive to controlling the very pest you are trying to get rid of. Many insects feed on squash bugs including stink bugs, feather-leg flies, and various assassin bugs. If you are not having any luck with natural predators controlling this pest, organic pesticides have been proven to help, but their residual effects are limited and may have to be reapplied more often and tend to work better against the nymphs which are not as mobile as the adults. As a last resort insecticides containing pyrethroids are effective against these insects. As always follow directions carefully, overuse of chemical control can and does create super bugs that are impervious to their usage.

Friday, August 13, 2021

Eastern Carpenter Bees

Of all the insects I receive calls about, carpenter bees are among the top five. Carpenter bees derive their name from their nesting habits, in fact their genus name of Xylocopa translates from ancient Greek to mean “wood-cutter.” A very fitting name for an insect with a preference for wood as their nesting sight. In the spring females will mate and begin looking for suitable locations to excavate a nest. Unpainted, untreated, weathered wood is her prime choice, and if the wood is cypress, cedar, redwood or pine all the better. These softer wood varieties make her life easier. She may also utilize nesting sights from previous seasons and just expand their size. Typically, their nesting behavior does not cause significant damage as the tunnels run along the surface of the wood, and not into the heart wood. However, the continuous use of nesting locations can cause problems. These nesting locations also attract an animal that can be a big issue for homeowners…. woodpeckers. These birds are attracted to the feeding and movements of the larva within the tunnels. They can hear them, and the temptation is more than they can bear, they will drill into the wood until they reach the tasty morsel inside. This can and does cause significant damage to homes, decks and other wood surfaces.

 Believe it or not some people do not notice these large bees, but rather find suspicious looking piles of sawdust on the ground under the eaves of their home, or in their outbuildings. Glance up, and you will find the culprit leaving you these little piles of wood shaving. Eaves of homes, rafters, fascia boards, wood siding, decks, patio furniture and other weathered wood are all at risk of being used as nesting locations.


Many people when faced with these large bees mistakenly thing they are bumblebees. It is easy to see why, they are similar in size and coloration. The major differences are nesting habits, carpenter bees are solitary nesters, meaning they do not form colonies whereas bumblebees typically nest underground in colonies with a queen. Carpenter bees also have a hairless abdomen, and bumblebees are extremely hairy or fuzzy in appearance. Female bumblebees tend to be territorial and very defensive of nesting locations and stings are common. Carpenter bees on the other hand rarely sting unless mishandled or provoked. Males of each species lack stingers and cannot sting. Male carpenter bees are very protective of females and the nesting areas, and they are also exceedingly curious about everything in their environment. It is not uncommon for the males to fly at people and hover in their face. If you are afraid of bees or allergic to their venom, this can be very intimidating, and you may not care to know if the culprit is harmless or not. For those individuals If it looks like a stinging bee…it is a stinging bee.  Males have yellow patches on their face that are visible at this range. Rest assured they cannot hurt you; they are just asking you to leave. Females typically stay busy boring into wood and laying eggs, they don’t have time to pay you a visit like the males do.

 She will bore a short distance into the wood then veer right and continue tunneling parallel to the surface of the wood. She creates five chambers that she provisions with pollen, after laying an egg in each chamber she seals them up with pulp made from bits of wood and saliva. In a few weeks the adults emerge. Often these new adults will spend the winter in the brood chambers and emerge the following spring.  These will be the adults that create the next generation. Occasionally other bees or wasps will be found emerging from these entrance holes. No need to worry, they are not compounding the problem created by the carpenter bees. These are opportunistic hunters looking for a cheap and easy meal in the form of leftover pollen.

Generally, the calls I receive are inquiries into how to control these bees or get rid of them entirely. While I can understand the concern, generally their feeding habits, while unsightly at times, are not damaging, certainly nothing like termites would do. These bees are known to pollinate many flowers and should be considered beneficial…although there are some sneaky individuals that have figured out a way to steal nectar without benefiting the plant at all. These thieves use their mouth to make a slit in the sides of flowers and enter through this opening, helping themselves to the tasty sweetness inside and leave without taking any of the necessary plant pollen to propagate the next generation of plants.

If you are determined they need to go, control can be challenging. There are homemade traps you can try. These traps are made from wood with a ½ inch hole drilled into each side and a plastic bottle suspended from the bottom. The bees investigate the opening and fall into the bottle. They are unable to climb out and die (Google carpenter bee trap).  When enough bees have accumulated simply empty the bottle and reuse. Others I know have had good luck using a brown paper sack. Fill the sack with air, tie it off at the top and suspend it near the area where the bees are boring into the wood. This air-filled sack resembles a bald-faced hornet nest, and these large wasps are sworn enemies of the carpenter bee. This may discourage the bees from using this area. Any surface that is unpainted may be painted as a way of discouraging them as well. As a last resort you can try various insecticides. Some may need to be reapplied frequently as their residual effect does not last long. Always follow directions carefully.

If their footprint is small and damage is minimal living with these large, curious bees benefits many of the flowers and vegetables we grow through pollination. Tolerance is almost always the best policy.