Emblazoned t-shirts, espresso mugs, and license plate frames exhort us to “Save the Bees!” Scores of organizations single out species of concern, equivalent to honey bees or native bees, whereas others promote any previous bee. In response to a consultant of the Xerces Society, bee coaching seminars that when attracted a half-dozen contributors now entice tons of.
This text first appeared in American Bee Journal, Quantity 162 No. 4, April 2022, pp. 405-408.
However no matter all the eye, one species in North America is slipping by way of the cracks, failing to make the minimize amidst all of the bee love. Many people who find themselves in any other case bee-centric are completely content material to slaughter this one explicit species. I’m not eager about non-native woolcarders or the launched Asian shaggy digger bees. No. I’m referring to our personal native jap carpenter bee, Xylocopa virginica.
The jap carpenter bee is a pollination wunderkind. It’s a giant hulking species adept at sonication, that important however uncommon trait that permits a bee to lock onto a plant and quiver, shake, and shimmy till the pollen explodes from its hidden chamber. Different sonicators dwell within the wild for certain, together with bumble bees and a few leafcutters. However with our love of the Solanum — equivalent to tomatoes, potatoes, and eggplants — and the Vaccinium, together with blueberries and cranberries, you may’t have too many sonicators.
So what about this charismatic bee crosses the road? Why does her photograph grace the partitions of the submit workplace? The reply facilities on territoriality. Not hers, however ours. We don’t like issues dwelling in — or transforming — our houses uninvited. “Mine!” we declare. “My home, my barn, my garden furnishings.” So we mark her for destruction, it doesn’t matter what she might have performed for our surroundings and grocery cabinets.
An abode of redwood
Once I was a child, my dad and mom purchased a round redwood picnic desk made from thick lumber, lovingly constructed, and fairly costly. Quickly after supply to our terrace, a big carpenter bee confirmed up unannounced. She hovered on the fringe of the desk and drilled straight into the wooden with a high-pitched whine paying homage to a dental workplace.
After my mother shooed her away, I caught my finger within the gap. It jogged my memory of a tiny check tube, rounded on the backside and clean as glass — the best factor ever. I used to be enchanted, however my mother was furious. She marched towards the home, promising to be proper again.
The place people go, carpenter bees observe
Like cats, carpenter bees want to dwell close to people who encompass themselves with helpful objects. Like us, carpenters admire fence posts, windowsills, fascia boards, railings, decks, shakes, and backyard gates, and if the wooden is unpainted, a lot the higher.
That carpenter bees really follow carpentry on these gadgets results in hassle. They adore new wooden, particularly softwoods equivalent to pine, fir, cedar, and redwood. They seek for lumber thick sufficient and mushy sufficient to excavate a nest in their very own trademark vogue, but when no milled lumber is on the market, cordwood or a lifeless tree will do.
A carpenter bee’s tunnel
The construct goes like this. The feminine drills straight into a bit of wooden perpendicular to the grain. At about one physique size — or roughly half an inch — she makes a tough ninety-degree flip. From there, she follows the grain, clearing a spacious cavity giant sufficient to put her eggs and accommodate the following era. These hole caverns are known as galleries.
The feminine shoves many of the shavings and sawdust outdoors. Typically you may see it drifting in a cloud or uncover a recent pile on the bottom beneath an excavation. They reserve the remainder of the shavings for partitions that may separate particular person egg chambers. Like many bees, the feminine begins a household on the far finish of a tunnel by fashioning a nectar-laced pollen ball and laying an egg on prime of it. Then she builds a particle-and-resin partition earlier than starting the following brood cell.
A carpenter bee egg is gigantic, one of many world’s largest insect eggs. Whereas a honey bee egg measures about 1.5 mm lengthy, a carpenter bee egg reaches 15 mm. However its rarity tempers the egg’s dimension: a mean feminine carpenter lays a couple of half-dozen in her complete life.
A maze of tunnels
One tunnel in a bit of wooden is annoying, but not too damaging. However carpenter bees possess a genetic trait referred to as philopatry, that means subsequent generations nest near residence if they’ll. Some will even return to their natal nest. Quickly-to-be mothers are social sufficient to share a entrance door with different mothers, every excavating a personal nest from the shared vestibule.
After just a few years, wooden that when hosted a single tunnel turns into laced with compound galleries, typically working parallel to one another alongside the grain. The a number of excavations may cause structural issues which will stay hidden. What seems as stable timber from the surface generally is a home of playing cards — a catacomb beneath a skinny veneer of wooden, able to collapse at any second.
Different annoying habits
Drilling into houses and possessions is the main criticism in opposition to carpenter bees, however not the one one. Bees going out and in of their houses wish to defecate on the nest entrance, leaving golden-brown streaks that stain the wooden beneath. Apparently, even individuals who can overlook the outlet are much less philosophical in regards to the fecal deposits, describing them as disturbing or low class. As anybody with honey bees is aware of, a fast squirt with the backyard hose solely makes the spots glisten.
As well as, some gardeners complain in regards to the injury carpenters inflict on their flowers. Identified for nectar robbing, they by no means hesitate to chunk into the bottom of a corolla to entry the nectar inside. Though carpenters are wonderful pollinators, they’re massive and unable to suit into skinny flowers with lengthy tubular petals. When a svelte flower guarantees a superb meal, the carpenters chunk their approach in, leaving slits within the petals that flip brown alongside the perimeters.
As a result of the slits are inviting, bees not adept at petal-biting may also go to the nectar cafe, having fun with a meal able to eat. Honey bees, particularly, wish to benefit from pre-split feed baggage.
And eventually, some householders complain that carpenter bees entice woodpeckers. The woodpeckers can detect brood beneath the skinny veneer of wooden that covers the galleries. With little effort, the birds can poke into the wooden, casting splitters and carving holes.
The intimidating males
Identified for intimidation, trespassing, and harassment, the males even have a PR drawback, if not a mugshot within the submit workplace. Due to their aggressive habits, many of us draw back from them, fearing an assault. A sturdy bee hovering in midair whereas making extended eye contact will be offputting, however that’s precisely what they do. Though they’re all bluster and pomp, with no weapons past beady eyes, individuals give them a large berth, preferring to exterminate reasonably than ignore them.
Like different male bees, male carpenters don’t have any stinger, however they collect in agitated teams and make aggressive passes in any respect who enter their territory. They’re unimpressed together with your dimension or your possession rights, in order that they attempt to make you permit.
The way to establish a carpenter bee
The jap carpenter covers a variety of territory in North America, starting from southern Canada to Southern Florida, and from the Atlantic coast as far west as New Mexico. Due to their monumental dimension, they get confused with bumble bees. However jap carpenter bees have a shiny, almost hairless stomach in comparison with the scary bushy stomach of a bumble bee. As well as, the top of the feminine is extraordinarily broad, like a buffalo. The male has a distinguished yellow facial patch, almost sq., that distinguishes it from a bumble bee. The thorax and first stomach phase (T1) in each sexes function yellow hair.1
Different species of carpenter bees dwell within the southern areas. The southern carpenter bee, Xylocopa micans, lives in southern Florida and alongside the gulf coast into Texas. We discover different species within the American southwest and northern Mexico, together with the valley carpenter (X. sonorina) and the western carpenter (X. californica). Some others have moved north from Mexico, together with subspecies of the horsefly-like carpenter (X. tabaniformis).2 Oddly, contemplating its abundance of softwoods, the Pacific Northwest is devoid of all Xylocopa, at the very least for now.
Worldwide, many species of carpenter bees are well-known for having sexual dimorphism, that means the men and women look nothing like one another. For instance, the valley carpenter feminine is apparent black whereas the male is a hanging golden yellow.
An invasive enemy
Within the early Nineties, a pest of the jap carpenter bee quietly entered North America. The sculptured resin bee, Megachile sculpturalis, is a protracted darkish bee within the leafcutter genus that nests inside wood holes and cavities. Discovering that native carpenter bee tunnels had been a lot to their liking, the sculptured resin bees rapidly unfold to all states east of the Mississippi.
Superficially, the sculptured resin bee seems just like the jap carpenter. It’s a giant black bee with rust-colored hair on its thorax, and since it hangs round carpenter bee holes, it’s ceaselessly mistaken for one. However the sculptured resin bee is elongated with a slender stomach as wavy because the floor of a plastic water bottle. As well as, the feminine has giant mandibles and carries pollen beneath her stomach, not in a pollen basket.
The resin bees will be brutal to carpenters that construct a fascinating tunnel. The interlopers assault the carpenter and smear it with sticky plant resin till it will probably now not fly. Observers have additionally witnessed resin bees biting the heads of carpenters and stinging. As soon as the maimed builder is out of the way in which, the resin bee strikes in, leaving the carpenter to die.3
A straightforward repair for carpenter bees?
With all their assorted debits, it’s straightforward to see why carpenter bees put on a bullseye on their backs, marked for extermination. However how aggressive ought to we be? Is there a solution to save these top-of-the-line pollinators and our private buildings?
When my mother got here again to the patio after discovering the carpenter bee injury to her picnic desk, she carried a round vinyl tablecloth. With zero entomological coaching, she adjusted the material to hold about six inches over the perimeter of the desk. It disenchanted me no finish as a result of the bee was cute, however I might see her level. The material labored, the carpenter by no means returned, and nobody needed to die.
To regulate carpenter bees, you may both deter them or kill them. Some of us wish to spray repellants equivalent to citrus oil or almond oil across the entrances to repel returning bees. As soon as the bees are out, the holes will be plugged with wooden putty, plastic wooden, or a wad of metal wool. Different individuals like to make use of loud music, wind chimes, or diatomaceous earth, none of which I can vouch for.
I do know entomologists who merely snag them with a butterfly web after which pinch every one. Though deadly, this technique is fast, doesn’t by accident kill different species, doesn’t poison your atmosphere, and gained’t annoy the neighbors.
Recall that carpenter bees are philopatric, preferring to nest close to their birthplace. That implies that when you rid your quick space of carpenters, others are unlikely to reach. After you web the adults in spring, try to be carpenter-free for the remainder of the 12 months.
Holding carpenter bees at bay
Numerous individuals advocate paint and polish for all wood surfaces the place carpenters are an issue. Though carpenters want uncoated wooden, if they’ll’t discover it, they’re probably to make use of your neatly painted windowsill. One workaround is to provide them an alternate, equivalent to a pile of untreated, unpainted softwoods at a snug distance from your home.
In fact, each time cash will be made, somebody will devise a product in your predicament. Proper now, carpenter bee traps are a factor, obtainable in all places.
The traps are available in numerous sorts, some with poison, some with pheromones, and a few with neither. Principally, a bee enters an attractive-looking gap lured by pheromones or just by seems. As soon as she enters, she both encounters insecticide or drops right into a catchment container from which she can not escape.
Personally, I wish to keep away from pesticides. Those in widespread use are deadly to all bees, not simply carpenters. Though there’s not a lot likelihood of collateral injury, I want to keep away from the complete pesticide situation.
Nevertheless, the traps that don’t use pesticides enable the bees to die slowly. Some individuals have stated that even after a number of days, some bees had been slowly writhing throughout the catchment jar, which appears unnecessarily merciless. Others have talked about seeing some quantity of by-catch within the jars, particularly bumble bees.
Bee condos gained’t work for carpenter bees
Oddly sufficient, a reasonably widespread “resolution” bought by many pest management corporations and backyard facilities is a mason bee rental. Advertisers declare the tubes lure carpenter bees away from your home and yard by giving them a spot to dwell. That’s nonsense.
Recall that carpenter bees have a signature ninety-degree bend of their tunnels that happens at about one physique size from the doorway. As a result of there’s nowhere to show inside a bamboo tube, they aren’t engaging to carpenters in any respect. Entomologists advocate that wooden designed to draw carpenters must be softwood, at the very least two inches by two inches in cross-section, and the size ought to run with the grain. This permits the carpenter to drill perpendicular to the grain after which make her right-angle flip.
Weighing the choices
I’ve no easy solutions, however I urge you to consider these bees earlier than dividing your pollinators into good ones and dangerous ones. Sure, carpenters generally is a nuisance, and sure, you don’t have time for them, however assume anyway.
When you should kill them, I urge you to web and pinch for per week to see for those who can scale back their numbers with out resorting to cruelty or poisons that may have an effect on different bugs. If nothing else, keep in mind that saving pollinators begins at residence.
Honey Bee Suite
Many because of nature photographer Bob Noble for his beautiful pictures, all taken within the Coronary heart Lake Conservation Space of Brampton, Ontario.
1 Danforth BN, Minckley RL, Neff JL. 2019. The Solitary Bees: Biology, Evolution, Conservation. P. 365. Princeton: Princeton College Press.
2 Carril OM and Wilson JS. 2021. Frequent Bees of Jap North America p.163–164 Princeton: Princeton College Press.
3 Frankie GW, Thorp RW, Coville RE, and Ertter B. 2014 California Bees & Blooms: A Information for Gardeners and Naturalists p. 70-76. Berkeley, CA: Heyday Press.