Bug Beds

Imagine you are an insect, and the nights are getting colder.  You don't really have a home to go to, but you need a place to snuggle in to survive the cooler nights.  There are a million places you could go.  You could hang under a leaf or sit on a tomato flower, but the real Ritz-Carlton of the insect world is the celosia flower, seen here.

Celosia

Celosias are gigantic, fuzzy, and filled with little crevices to lodge for the night.   There is even breakfast in bed for their guests, because the flowers provide plentiful nectar for bees, wasps and other insects.  I imagine it must be very pleasurable to settle in to these soft, velvety flowers.

Hive-less, or solitary bees will often nestle into or under a flower to get through the night.  If you go into your garden very early in the morning, you will undoubtedly find some sleepy bumble bees or wasps curled up inside your squash flowers or daisies.  If the morning is cool, you can even touch the bees - they will be too cold to panic. 

This week, we had an exceptionally cool day.  It was 95 degrees one day and 60 the next.  The bees and wasps (and the rest of us) were caught off guard, and they didn't leave their flowers for the entire day.  As I harvested celosias, I noticed bumble bees, cicada killer wasps, ichneumon wasps and many other wasps and bees sitting inactive amongst the celosia blooms.  I could get as close to them as I wished without disturbing them.  Unfortunately it was also raining, so I didn't get pictures.  You'll have to make do with this picture of a cart loaded with gorgeous celosias that I harvested. 

Cart of celosias

Not All That Buzzes is Black and Gold

The airspace on the farm is busy.  There is no air traffic control, but no one seems to collide.  I'm a giant lumbering along amongst the cloud of busy insects as I work my way down rows of flowers and vegetables.  They hardly seem to notice me as they go about their work.  With so much time and so many insects, I've gotten to know their sounds well.  You can tell an amazing number of buzzing insects by the qualities of their buzzes.

The easiest to recognize are the cicada killer wasps I wrote about a few weeks ago (here).  They have a steady bass tone - a low buzz in which you can occasionally hear individual wing beats.  They are loud and their pitch only changes from the Doppler Effect, lowering a bit as they fly away.

Cicada killer wasp.  Picture source.

Bumblebees are the most common on rows of flowers.  Their buzzing is all fits and starts as they whiz from one flower to the next.  They seem to have trouble steering because they swerve around a flower's entrance before crawling onto it, so their pitch varies widely as they try to align themselves for landing. They are generally loud and low in pitch.

Bumblebee.  Picture source.

Honeybees are quiet and unfortunately rare on the farm.  They move and sound a lot like quiet, higher-pitched bumblebees.  If bumblebees are the bases, honeybees are the tenors.  Sweat bees are the sopranos.  They have these little tiny, quiet buzzes as they try to wedge themselves into the backs of your knees so they can sting you when you squat down.  They are usually unnervingly near you, and they whiz off when you try to swat them.

Sweat bee.  Picture source.

The bugs, stink bugs and assassin bugs, are hilarious once you get used to them.  They buzz so stereotypically that I expect them to have little captions over their heads filled with z's.   They hide amongst the green parts of plants instead of the flowers, and they wait until the last minute to try to escape from a perceived threat.  I'll be harvesting tomatoes and all of a sudden a loud buzzing bug will be flying erratically very near by.  No other buzzing insect buzzes so close and loud. 

 

 

 

Leaf footed bug.  Picture source.

There are some stealth insects too.  Wasps usually don't make a sound.  If you are very quiet, you can hear a little purring noise when they are very close, but usually they just seem to float by noiselessly.

Paper wasp.  Picture source.

Giant Hornets of Death: Cicada Killer Wasps

For some reason in my Entomology class, my professor really liked to talk about giant ground hornets and how territorial and mad they were.  He told us they would be a trophy to add to our insect collections, but that they were dangerous to catch because their sting was so painful.   Unfortunately, I was afraid of them for years until the owner of the farm on which I work told me that the insect I knew as a giant ground hornet was the same as the cicada killer wasp, which her 9-year-old son loves to follow because of their unique behaviors.

Cicada Killer Wasp, picture source

Well, I had to do some research, and she is absolutely right - they are the same, and cicada killer wasps are generally docile and always awesome.  I actually got to know cicada killer wasps a few years ago because there were dozens of them living in an ivy patch outside the school where I used to work.  We science teachers had to research them to see if they were a danger to the students, and we decided that they were so easy-going that we'd just keep kids from walking through the ivy and that the third graders would study them as part of their Biology unit.  They loved it and no one got stung.  I wish I had connected the dots at that time between cicada killers and giant ground hornets, because I had a close encounter with a giant ground hornet on the farm last week and had a very unnecessary scare.  It would be less confusing if we all just used the scientific name, Sphecius speciosus.

Cicada killer wasps/giant ground hornets are gigantic, up to two inches long.  They are yellow/orangeish and black and variously patterned with usually black abdomens.  They are charismatic animals, and they live large on the landscape.  When they are present, you will see them, but don't be afraid.  The females are technically capable of stinging, but they won't unless they are actually handled.  I'm assuming the ones in the picture below are deceased, either that or they are in the process of stinging.

They're gigantic!  Source

Cicada killer wasps emerge from the ground in early summer.  They feed on flower nectar and search for mates.  After they mate, the females dig a burrow 1-4 feet into the ground, piling up dirt at the entrance to the ground.  The burrows are quite visible in lawns, and many lawn-farmers usually don't appreciate the mini-mole-hills.  They wasps actually prefer bare soil, since it's easier to dig through.  Males cruise around the entrance to the burrow, protecting the burrow from enemies and other males.  Their buzz is definitely bigger than their bite because males can't sting.  Still, they can and do fight fiercely in mid-air, careening around in wrestling-holds with their competitors.

After digging a burrow, the females go on the hunt.  They search for cicadas - but not to eat.  When a female finds a cicada, she stings her prey, paralyzing it but not killing it.  Then the female begins the gargantuan task of hauling the cicada, which can be three times her weight, back into her burrow where she will lay an egg on it and seal it into a chamber.  The egg hatches into a larva which then slowly eats the cicada until the cicada is a shrunken shell and the larva is huge.  Females will make several chambers in each burrow - each of her children gets its own room.  The kiddies overwinter as larvae to emerge next year.

The Wasp Finds a Victim, Source

It seems the female can tell the sex of the eggs she lays.  Her female offspring get two or three cicadas to eat, and her male offspring get just one.  Females grow much larger than males, so they need more food.

Cicada killer wasps have their own parasites that lay their eggs on the cicada killer larvae.  Velvet ants, which are wingless wasps, are parasites on parasites.  If you must fear an insect, you could choose velvet ants (also know as cow-killer ants, though they don't actually kill cows).  Velvet ants have a MAJOR sting, which I can attest to from personal experience.  If you see one, don't bother it!

Velvet Ant Source