Thursday, July 24, 2014

What's the Point of Gardening? A Gardening Ethic for Our Times

Why do you garden?

If you're like me at all (and I suspect that many gardeners are), you probably have several reasons you garden - several passions that gardening feeds - several functions that gardening performs in your life....

I garden because it makes me feel good to see flowers blooming around my home.

I garden because it's a form of exercise that I enjoy and it gets me outside, in the fresh air.

I garden to increase our property value (I hope).

I garden to provide some good, chemical free food for us to enjoy.

I garden because plants and animals fascinate me in their infinite variety.

Most of all, though, I garden because it's my way of doing something very concrete, very local, and very specific to make the world healthier and more ALIVE.  I garden, and I garden the way I do, because it's my way of helping to heal the life force on our planet, which seems to be in serious danger from the increasing human assaults on it over the last 100 years or so.

"Okay, Cynth, " I can almost hear you sigh.  "What brought this up?  Can't we just look at pretty pictures and move on?"

Well, of course you can.  But I read something the other day that really got me thinking about my role as a gardener.  Ben Vogt of Nebraska, who blogs at The Deep Middle, posted a commentary that struck a deep chord with me:  "Is There Any Difference Between a Land Ethic and a Garden Ethic?"
Hmmm.  Is there?  Why DO I garden?  Why do most people garden?

Ben started his thought-provoking post by quoting bits and pieces from Aldo Leopold's wonderful statement about developing a land ethic, as written in A Sand County Almanac.  Leopold finished writing this small, but important, three part book in 1948, just before he died.  The book was published a year later.  I think the most concise statement of Leopold's land ethic is actually written in Leopold's own forward to this book, "We abuse land because we regard it as a commodity belonging to us.  When we see land as a community to which we belong, we may begin to use it with love and respect."  (My italics)

Filling the last 25 pages of A Sand County Almanac, the entirety of Leopold's "The Land Ethic" is certainly too long for me to quote here, but it's well worth reading...and rereading.  In it, he moves from showing how we humans have developed our ethical codes, first working on the relationships between individual humans and later developing codes such as the Golden Rule and democracy for how the individual relates to society as a whole and how society relates back to the individual.  Now, Leopold believed, it had become necessary to develop another layer to our ethical codes to govern how humans related to the land and to the plants and animals that shared it with them.  Otherwise, in Leopold's words, "There is no other way for land to survive the impact of mechanized man...."

Aldo Leopold wrote in 1948 and presumably developed his ideas even earlier.  What would he say about the way we treat the land, and the plants and animals on it, now?  I'm rather glad he's not around to see what we've done and, even worse, what we're in the process of doing.

Because I am around to see what we've done and what we're currently doing, I try to treat our little 10 acres according to Leopold's Land Ethic, adopting this ethical code, to the best of my ability, as my gardening ethic.  I try to treat our land, with its associated plants and animals, with love and respect, thinking of it as a community that I belong to rather than as a resource to maximize.  Realizing that communities - like most complex things - are healthier when they have all of the parts that they should have, I am trying to reintroduce plants that have disappeared over the last 150 years while this parcel of land was being extensively and intensively farmed.  I'm hoping that, as the plants reestablish, many of the smaller animals will find their way back too.

My goal is to have as stable, as healthily functioning, a prairie community on our 10 acres as I possibly can.  Someday, perhaps, the plants and animals that remain on this tiny piece of land will serve as a source to move back out into the wider landscape as a whole, helping to heal it as well.

Towards the end of "The Land Ethic," Leopold talked about a schism among folks who work with and on the land - he called it a cleavage - that divided people into 2 camps which deeply affected their relationship to the land they worked with:

In all of these cleavages, we see repeated the same basic paradoxes:  man the conqueror versus man the biotic citizen;  science the sharpener of his sword versus science the searchlight on his universe; land the slave and servant versus land the collective organism.  Robinson's injunction to Tristram may well be applied, at this juncture, to Homo sapiens as a species in gelogical time:
Whether you will or not
You are a King, Tristram, for you are one
Of the time-tested few that leave the world,
When they are gone, not the same place it was.
Mark what you leave.

As a gardener, which cleavage do you belong to:  the conqueror or the citizen?  Is your garden your slave and servant or a community that you belong to?  When you are gone from your garden, what will you leave for the future?  What mark will you have made?


Saturday, July 19, 2014

Spiders Galore

Usually I think of late summer and early fall as "The Spider Time of Year", but I'm seeing quite a few spiders around the yard right now, in what I would consider mid summer.  What's even more interesting is that most of these are a little different from the spiders I tend to see later in the season.

For starters, I'm seeing a lot of the black and yellow garden spiders (Argiope aurantia) already, but they are comparatively tiny.  Mind you, I've always known that black and yellow garden spiders were out there all summer long, growing from tiny spiderlings to adult size, but I don't normally notice them until they get huge and hang their webs outside the kitchen door, around the compost pile, or between the beds in our vegetable garden.  I'd say the average one I'm seeing right now has a slender body whose length is right around 1/2", which is a far cry from the inch long (and almost as wide) female "monsters" more common in September.

On July 6th, I was lucky enough to catch a glimpse of this large spider (I'm guessing a wolf spider) molting in the tall grass.  Because I always worry that I'll disrupt an animal in a detrimental way if I hang around too long during a vulnerable period in their life span, I didn't stay around to watch the molting process, but I did grab a couple of quick photos.  Molting is amazing, when you stop to think about it.  You can see every minute external structure of the animal in its shed exoskeleton.

The last few days have been especially rich in spider sightings.  For example, despite glaringly obvious webs, I've only been able to capture glimpses of funnel spiders before.  Yesterday, however, I was able to get a pretty good look at this Grass Spider (Agelenopsis pennsylvanica) on its rain spotted funnel web, located in a clump of Husker Red penstemon in the back courtyard.

Four days ago, this cute little guy was hiding in the leaves of one of our bur oaks (Quercus macrocarpa) out behind the back courtyard.  I've never seen a spider marked in quite this way, but my spider book tells me its a male jumping spider (Hentzia palmarum), the Common Hentz Jumper.  The female looks quite different, basically a drab brown with spots.  I could very easily have seen her and not remembered it.

In the flower gardens, I'm frequently seeing little crab spiders on Echinacea blooms...which obviously tax their camouflage abilities beyond capacity.  The yellow or white coloration that works so well for them on goldenrod, sunflowers and other blooms doesn't hack it on Echinaceas, but evidently the little crab spiders are still able to catch what they need.

Last, but most certainly not least, I've been seeing quite a few wolf spiders.  Big wolf spiders with really pretty, textural patterns on their abdomens.  Again utilizing my spider book, I've figured out that they are Rabid Wolf Spiders, Rabidosa rabida.   How's that for a name?  (As if large spiders didn't have enough of a P.R. problem?!)  Were they given their name because their large size made people act mad (rabid) with fear?  Or did their quick movements made them seem rabid?  One site listed the latter hypothesis, but I suspect it's the former.

If you're the sort to worry about such things, you'll be happy to know that, despite their size and although their bite IS painful, rabid wolf spiders are not poisonous to humans and the pain from the bite will rapidly subside.  Personally, I just wouldn't pick one up!  That moves the chance of getting bitten to just about zero.

I love seeing spiders around the yard.  They help maintain ecological balance by capturing and eating a wide variety of insects and, occasionally, other spiders. While I'm not overly excited about accidentally running into spider webs, especially face first, most of the spiders I'm seeing right now either don't make webs or they don't make webs that I'm likely to run into.  Even the black and yellow garden spiders are spinning their webs deep down in the middle of perennials right now, rather than high up across pathways.  Have you seen any interesting spiders in your garden lately?

After-The-Fact Discoveries Through the Camera Lens

I can't decide if I'm blind or just too single focused....

Take this photo, for example.  When I took the photo, I was focusing on the cicada that is positioned vertically on the green ash suckers and on the empty "shells" that are located above and to the right of it, one of which I presume it emerged from.  ... Until I looked through my recent photos after downloading them to my computer (the next day), I literally didn't see the second cicada in this photo, located on the horizontal stem above and to the left of the first cicada.  Of course, by then, both cicadas were long gone, so any chance to focus more tightly or to change my framing had disappeared along with them.

Luckily, in this case I did take this second photo, which gave me a little better look at the second cicada...

...and this third photo, which allowed me to incorporate another, newly emerged cicada I had noticed about a foot away, which you can see at the bottom left in this photo.  The original one...er, two are at the top right.

How did I miss that third, newly emerged cicada?!  I wish I knew, because then I might not miss other "minor details" as I'm out and about....

As I did in this next photo, which I took one night earlier this week....

To explain, I'm seeing at least 4 different toads (I think) around the house this summer, but I've been wanting to verify if they are all the same species.  This toad, which is the same size as one I'd seen earlier in the day, had different markings, so I wanted to catch a photo of it.  I was so focused on the toad, however, that I totally missed the click beetle just in front of it on the ground.  I don't recall seeing a click beetle of that size around here before, so I'm really curious as to what species it might be - but it, too, is long gone...although whether it flew away to live for another day or disappeared down the gullet of the toad, I'm not sure!

Oh,in case you're curious, this toad is a Great Plains Toad (Anaxyrus cognatus), while most of the others I see are Woodhouse's Toads (Anaxyrus woodhousii).  I was right to notice the different pattern of spots.

Do you ever make discoveries of this sort in your photos, after you bring them up on your computer screen, or are you a good enough observer that this never happens to you?  I'd sure love to hone my skills of observation enough that this quit happening!  I wonder what else I'm missing when I'm NOT taking photographs?!

Sunday, July 06, 2014

Weeds: What Are They Good For?

It just doesn't seem fair.  When you clean a surface, it ought to stay clean, unless you put something on it that dirties it.  Right?!  So why is it that, after you've worked hard to weed a flower bed or vegetable garden and you have a beautifully pristine expanse of bare soil in between each plant, the weeds show back up?  Seemingly like magic!  Sometimes they seem to spring up overnight.

These weedy interlopers are unwanted and they crowd out the plants that you want to grow!  Isn't this a design flaw in nature?!

Well, actually, no, there's a very good reason for this to happen in nature.  Weeds are nature's way of "preserving its capital", to use economic terms.  So what do I mean by "capital"?

In an ecosystem, soil is one of the most important resources available and one of the hardest resources to manufacture.  Originally soil formed from bedrock.  It takes thousands of years for soil to form:  soil formation involves the slow action of water and weather (especially the freeze/thaw cycle), acids from lichens, and eventually, organic debris and the action of plant roots.  Soil is NOT a substance that it's wise to waste, because its replacement takes thousands of years.

Enter most "weeds".  What we consider weeds are usually fast growing plants that produce thousands and thousands of seeds which transport readily, in a variety of ways, and which require sunlight and open soil to germinate and grow.  Once established in a good spot, these plants will reproduce rapidly and repeat the cycle of producing thousands and thousands of easily transportable seeds.  What's the point of this process?

Well, these same plants' seeds and seedlings cannot compete in a crowded, shaded location.  In a setting like that - a more established setting - they get outcompeted by other plants that don't have to start from scratch every year.  Plants like perennials, with well established roots that can send up tall stalks in a short period of time and dominate the sunlight, will outcompete them.  Plants like shrubs and trees whose roots are not only established, but that can leaf out and block the sunlight seemingly overnight each spring, will outcompete them.

In fact, if you stop to think about it, if humans do nothing to a piece of land, the vegetation changes through the years in a fairly predictable pattern.  First, the open ground gets covered with "weeds", often a mix of annual grasses and annual, broad-leafed, flowering plants.  Pretty soon, a few perennials start to show up and establish themselves and, before long, there are some seedlings from woody plants beginning to grow.  As the perennials and woody seedlings grow up, the "weeds" that need full sunlight and open soil, so that they can start from scratch every year, start disappearing.  Eventually, the vegetation continues to change until only plants that can germinate and grow in shady, crowded conditions dominate.  This entire process is called ecological succession; the final types of vegetation that will grow in an area are known as the "climax vegetation."

So what happens if the climax vegetation gets removed?  Succession begins again - with the "weeds" whose seeds are easily transportable showing up.  Their job, if you will, is to hold the soil in place until more permanent vegetation can take over and maintain the capital, a.k.a. the soil, that has built up over thousands of years.

The more the soil is disturbed, the more "weeds" will appear.

What we are doing when we garden or farm is to continually remove the perennial vegetation and take the soil back to its most vulnerable state - bare and open.  Nature wants to stabilize that soil as soon as possible, so that the soil doesn't wash or blow away.  In come the weeds.

The gardener - or farmer - cusses the weeds and clears the soil again, so that ONLY the plant he/she wants to grow will be there.  But rarely is the desired plant able to fill the cleared space rapidly enough and completely enough to truly stabilize the soil.  So in come the weeds again.  And the cycle continues.

Along the roadside, this mix of plains coreopsis, cheat, wheat stubble and field weeds is composed of essentially all annual plants.  The wheat was desired; the rest of the mix is considered "weeds", at least to the farmer.  Why is it all growing here?  Because the soil has been exposed recently and nature is trying to stabilize it.

If you widen the view to take in the entire ditch, you see that where the soil hasn't been plowed or opened by herbicide action recently, a mix of perennials is growing:  butterfly milkweed and various prairie grasses in this case.  It's far from perfect, since frequent low mowing often opens up soil, encouraging other, early successional, "weedy", plants to move in.

The moral of my tale?  Understand what nature is trying to accomplish with "weeds" and plan accordingly.  Learn to work WITH nature, rather than fighting against it.  Mulching between plants, for example, helps tremendously because it covers (and helps stabilize) the soil.  Mowing high (or not mowing at all) is likely to leave much less soil exposed and thus make an area less amenable to "weed" growth.

Why do I keep putting the word, "weed," in quotes?  Because a weed is simply a plant in the wrong place.  To nature, bare soil is a form of an emergency and what we humans call "weeds" are nature's emergency response team.  Therefore, to nature, annuals are important...and aren't weeds at all.

Saturday, July 05, 2014

Facing the Spider Wasp Gauntlet

For the last 5 summers or so, generally during June and July, I find myself facing a gauntlet of hovering, blue-winged, red wasps every time I pass through the opening between our breezeway and the back yard.

Wasps are my "phobic animal", so it takes a bit of courage every time I venture this way, usually to take the trash or recycling out or to water plants.  I've never been stung or even threatened with stinging, despite going through this gauntlet many times, but the hovering wasps give me an adrenaline jolt nonetheless.

Last summer, I finally figured out what these wasps were and what was going on, which I blogged about in "The Wasp Version of Baby Bottles":  these are (solitary) spider wasps, probably of the genus Tachypompilus.  That means my gauntlet of hovering wasps are a bunch of males, checking me out to see if I'm a female wasp in need of their fertilization services.  Since they have no egg-laying equipment, they have no stingers and couldn't hurt me if they wanted to...a biological pronouncement that I am, nevertheless, NOT going to test!

Interestingly, two weeks ago when I visited fellow Master Gardener Sid's home (which is about 5 miles from mine "as the crow - or wasp - flies"), I saw that he and his wife have a population of the same species of wasp.  Their spider wasps also make their nest cells between the finished concrete surface of their porch and the rougher foundation, just like mine.  Sid and Sandy, too, have watched the female wasps bring back paralyzed spiders to provision those nest cells for their eggs/young.

Occasionally I get a glimpse of a female out in the garden, prowling for her spider prey.  They move very quickly and, like most predators, are well aware of my presence.  They hide as soon as they possibly can, even while continuing to hunt, which makes photographing them a real challenge.  I usually see them on the ground, but that may just be a function of when I'm most likely to be still enough to notice them, which is when I'm weeding.

The more I learn about wasps and bees, especially about our native solitary species, the more interested and enamored I become.  Unless you try to capture a female and hold her, they are extremely unlikely to sting.  These wasps are important predators, helping to maintain balance between plants and plant-eaters and predators in our gardens, as they provision their nest cells with spiders or caterpillars or grasshoppers or cicadas.

And speaking of cicadas, I'm hearing the first few males warming up now in the afternoon.  The summer chorus is about to begin...and the cicada killer wasps won't be far behind.

Cicada killers are huge, frightening looking wasps that nest in bare dirt, often underneath decks.  Just as in "my" spider wasps, the males patrol the nesting area, trying to find females to mate with - but despite their scary looks, they have no equipment they can use for stinging.  The females can sting, but they are inevitably too busy hunting for cicadas and lugging them back to their nests (which they alone dig out) to bother with humans nearby.  Just don't try to pick one up....

In general, I'd say the spider wasps are around for about 2 months, and the cicada killers generally are seen for only about a month.  So if you find yourself sharing your garden with these winged creatures, have patience, keep your eyes open for the hardworking females, and practice conquering your fears!  Your yard will be healthier for it.

Friday, July 04, 2014

Wheel Bugs Vs. Walnut Caterpillars

Two days ago, I noticed a mass of small, hairy caterpillars on a single leaflet of a pecan leaf.

Today, I took a close look at the pecan again and discovered 3 separate masses of the hairy caterpillars, which I later identified as walnut caterpillars, Datana integerimma, a well known pest of walnuts and pecan trees.

Two of the groups of caterpillars seem to be developing with little interference, at least so far.  The above group was the furthest along in their development.  I need to decide what, if anything, I am going to do about them.

Meanwhile, the third group of caterpillars had attracted some attention.  Some lethal attention, actually.  Two wheel bugs had positioned themselves between the caterpillars and the healthy leaves of the twig they they were on.

Both wheel bugs had caterpillars that they were feeding on.  They appeared to be capturing each caterpillar as it attempted to move to a new leaflet to feed.

Wheel bugs, like most predatory insects, are VERY aware of their surroundings.  It is hard to sneak up on them, and these two were no exception.  As soon as they saw me, they hid...and every time I repositioned, so did they.

One shot I got silhouetted one of the wheel bugs eating a caterpillar against the sky.  I found that the sight of the wheel bug's pair of legs, locked around the central rachis of the pecan leaf as it fed, made me feel almost protective of this fierce predator.

(Note:  The caterpillar is the slightly hairy thing, hanging from front of the wheel bug.)

Anyway, according to the information sites that I found on the web, I probably should get rid of these caterpillars while I can.  This is probably the first generation...and there is usually a second generation too.  The caterpillars usually cause their most extensive damage in the last instar before pupating; then the second generation will cause more damage, as it's likely to be larger.

The wheel bugs will presumably take care of the one cluster that they are systemically guarding and eating.  That leaves the other two clusters.  If I destroy them by plucking the leaves and drowning the caterpillars in soapy water, I may be able to keep further damage from occurring.  But then there is no further chance for other predator or parasite numbers to increase.  According to the Forest Service information sheet that I linked to above, there are at least 13 parasites known to attack these caterpillars, as well as several predators (such as the wheel bug and certain spiders), and viruses and other diseases.

For now, I think I will let nature take her course and just observe.  Reality "television" at its most real!

Two More Monarchs...Hopefully

About 10 days ago, on a walkabout through the back of our property, I found two little pieces of hope.  First was this monarch caterpillar on one of the smooth milkweed (Asclepias sullivantii) plants....

Second was a monarch chrysalis, which I just happened to notice in the far back.  The nearest milkweed, green antelopehorn (Asclepias viridis), was at least 5 feet away, probably farther.

When I went back out for another walkabout yesterday morning, I didn't see any caterpillars on the smooth milkweed plants.  While I would have loved to find another monarch caterpillar, I was quite sure that the cat I'd seen last week had already pupated, given its size 10 days earlier...and I had no expectation of finding where the chrysalis was hanging.  So I wasn't surprised, although I was a little disappointed.

In the Back 5, I looked for the chrysalis that I'd seen.  Since it had been in the middle of a pretty featureless area, I wasn't sure I'd be able to find it again, whether or not the butterfly had emerged.  Therefore, I was really tickled when I DID find the remains of the chrysalis, looking to me as if the butterfly had successfully flown.

So, this year my property has provided at least one (and hopefully 2) more monarch(s) to the country's population.  And those are just the ones I've found.  It makes me feel good, like our yard is helping the Earth stay just a little bit healthier.  Long live the monarchs!

Sunday, June 29, 2014

An Experiment With Butterfly Milkweed

We moved into our home 7 1/2 years ago.  Since then, we have traveled 71st Street to Hoover Rd., going to and from Wichita, at least twice each week.  Conservatively, then, I'd estimate that we've driven by this one spot roughly 100 times a year, for a grand total of about 750 times since we moved here.

Despite driving the same route so many times, it wasn't until yesterday that we spotted beautiful, big butterfly milkweed plants in the ditch along our normal route!  That's right.  Butterfly milkweed, a.k.a. Asclepias tuberosa, with its vivid bright orange blooms.  It's not like this plant is a shy, quiet little mouse, hiding down among the grasses.  No, this plant is a hussy, shouting, "Look at me, world!!!"  And we'd missed it, time and time again.

Now, to cut ourselves some slack, butterfly milkweed would only be in full bloom for about a month, maybe two, each year as we drove by.  Make it an average of 6 weeks per year.  That still means we drove by about 75 times and never saw these plants before.

In our defense, of course, the county road crews have been ridiculously vigilant about mowing the roadsides to a dirty, ragged stubble most years.

But still!

Truthfully, we almost missed the butterfly milkweed yesterday too.  I caught one glimpse of the vivid orange as we drove by, so I asked Greg to turn around so I could verify that there was a plant there.  The orange of butterfly milkweed is incredibly distinctive, so I was pretty sure what I'd seen.  Not only was there one plant, there were FOUR!

It was so exciting to find these plants, the first truly local butterfly milkweed that I'd seen since moving here - but it was rather depressing, too.  Did I mention that the county roadcrews have been great about mowing everything down to a depressing stubble several times a year during each growing season?  The chances of these plants being allowed to set seed is close to zero.  Truly, I'm amazed the plants are alive and as vigorous as they are.

You can't dig native milkweed.  The roots are too deep and you'll kill the plant.  That goes double for attempting anything at this time of year, when it's hot and the plant is blooming.  So I couldn't rescue them that way.  No seeds likely and no transplanting possible.  What to do?

Greg did a little research on the web and started seeing reports of taking milkweed cuttings.  It didn't seem like a viable option, but several sites were reporting success.  The county would be butchering these plants soon anyway - why not try a couple cuttings and see what happened?

So this morning, armed with peanut butter jars of water, clippers, and my camera, we set forth.

Up close, the individual plants were even more stunning than they'd been from the road.  Three of the four were amazingly full of flowers and had obviously been blooming for quite a while, yet still showed new buds that spoke of blooming for much longer still. 

The color of the blooms was a deep, deep orange with hints of red - definitely a deeper color than the orange butterfly milkweed plants in my front garden bed.  The ones in my garden weren't blooming any more either.  They had bloomed for 2 or 3 weeks, and then quit a week or two ago.

While I was looking at the first plant, a butterfly flew in and started to nectar.  It was yellow, which usually denotes a sulfur of some sort, generally a fairly common butterfly.  However, I noticed that the black wing tips were particularly dark.  Then I realized that the tips of the front wings were squared off - a Southern Dogface butterfly (Zerene cesonia)!  Not an unknown butterfly in this area, but not one I commonly see either.

As I watched the butterfly, I debated what to do.  I looked for stems that didn't have blooms on them, thinking those stems would be more likely to root successfully, but there weren't any.  Eventually I carefully selected 3 stems from 2 of the plants and 2 stems from one other.  Why not take cuttings, despite the many blooms?  They'll all get sheared off soon anyway.

Back at home, I carefully removed lower leaves, blooms, and flower buds, dipped the end of each cutting in rooting hormone, and stuck them in wet perlite.  Plastic bags went over the cuttings to keep the humidity of the air up around them until (hopefully) they start to root.  This is my little forest of butterfly milkweed cuttings on the kitchen counter.....

Wish me luck!  I'd love to have some local genetics, especially since these individual plants are so incredibly full of blooms and so deeply colored.  We'll see what happens. 

An Unexpected Visitor: Anise Swallowtail

Late yesterday afternoon, when we went out to do some work in the garden, I noticed a different looking swallowtail nectaring on the Echinacea.  Grabbing my camera, I started trying to capture it on "film".

The swallowtail was much more skittish than most of the other butterflies I see in the garden.  At first, it was hard to get within 15 feet of it, although after a while, I was able to sneak up a bit...

...especially when it started interacting with a tiger swallowtail female that was also nectaring on the Echinacea.  I don't recall ever seeing an aggressive butterfly before, but that's what this individual acted like.

He (?) would come up behind the female and sort of dive bomb her.  Then they would do a circling dance through the air (was it a male trying to initiate a courtship dance?).  Eventually they would both settle back down to nectaring again.

Neither my Kansas City butterfly guide nor my Peterson's Eastern Butterfly guide had this swallowtail in it, but I finally found a photo in another, nationwide, guide that I have.  I verified my identification by checking it against anise swallowtail in Bugguide.  Sure enough!  That was it!

Now I'm left to wonder if this individual was an accidental import on a plant (or firewood? or a vehicle?), or if it is simply a stray, far from its normal range in the western parts of the U.S.  I doubt I'll ever know, but I'm sure glad I happened to notice the visit of this charismatic stranger.

Sunday, June 22, 2014

Wheel Bugs Growing Up....

Preying mantises and ladybugs have great reputations as good predators in the garden, but I've found a species that I think is even more awesome:  wheel bugs (Arilus cristatus), in the assassin bug family.  Like preying mantises, wheel bugs are very mobile and eat almost anything they can catch.  I've observed them eating a wide variety of insects, ranging from grasshoppers to beetles to caterpillars.

Wheel bugs have only one generation per year so, as with most predators, it takes them longer than plant-eating insects to ramp up their numbers after a population crash.   This is why, when you spray insecticides (which indiscriminately kill ALL insects), predator populations take so long to catch up that the plant-eaters/prey insects end up having huge population explosions in the meantime.  This is great for insecticide companies, but not so good if you're trying to use fewer chemicals in your yard or garden.

Overwintering as eggs laid in clusters on the underside of tree branches, the wheel bug life cycle begins when the tiny new nymphs hatch out in late April or early May, just about the same time that the honeylocusts bloom.  Although I occasionally find wheel bug eggs on other trees, most of them seem to be laid on honeylocust.  I doubt this is coincidence.  The egg cluster above, about the size of a quarter overall and located, like usual, underneath a honeylocust branch, was just starting to hatch on April 21st this spring.

When the tiny wheel bug nymphs hatch out in late April or early May, they look very different from their parents.  For starters, they have a bright red abdomen.  (Actually, when they first hatch out, they are completely yellowish-orange, until their exoskeleton hardens the first time.)  There is no "wheel" structure on their back and they, of course, have no wings.

Even at this tender stage, they are fearsome predators.  On May 11 this spring, I photographed this 1/4" wheel bug nymph carrying (and sipping on) the pupa of another insect, firmly pierced by its proboscis.

With each succeeding molt, the wheel bug nymphs' appearance changes just a little.  They get a little more gray and black, a little less red.  However, they never lose their fierce abilities as predators.  On June 7, this wheel bug nymph had moved from the tree where it was hatched to a clump of Jerusalem artichoke about 30' away, where it enjoyed a tasty meal of grasshopper nymph.

The photo above is, unfortunately, rather blurry, but I was lucky enough one day to spy a wheel bug nymph molting under a leaf of American plum.  The exoskeleton of the newly emerging nymph is, again, orange until it hardens.


That same day, June 8, I found this nymph hiding in daisy fleabane by its discarded, old exoskeleton.  It had obviously also emerged recently; the new, larger exoskeleton was not yet hardened and darkened to the normal colors of gray and red.

Also on June 8, I found this wheel bug nymph eating what looks to be a small caterpillar while posing on a spent bud of lanceleaf coreopsis and sporting a classy red and black abdominal outfit.

Right now, on June 22nd, I'm seeing nymphs that have turned almost completely gray, but that still don't sport the adult's wheel structures on their thorax or their wings.

They are still busily eating their way through the insect population of my yard.

Here in south central Kansas, the earliest I've seen a mature adult is July 21st... or at least that's the earliest I've photographed an adult.  The above photo was actually taken on September 9th in 2008.  In it you can clearly see the wheel on the back of the thorax, as well as the wings folded neatly over the abdomen.  All red coloration is gone from the body, although a little remains on the legs and antennae.

The adults continue to feed, essentially indiscriminately.  Here an adult female is feeding on a tiphiid wasp that was herself feeding on goldenrod nectar.  Actually, in this case the wheel bug's choice is rather unfortunate, since tiphiid wasp larvae parasitize white beetle grubs, the kind that eat grass roots.  Judging from this female wheel bug's abdomen, though, she has eggs of her own that she needs to lay.

By October, the new egg clusters are being laid and the year's adults are beginning to die off.

This female was still around on November 15th last fall, but her will to live seemed to be ebbing.  I watched her for a long time as she sat right next to this tachinid fly, but she never made the move to pounce on it and eat.  I figured that she must have laid her quota of eggs and be feeling worn out and ready to go. 

As cold weather hits, all the adult wheel bugs are gone and the future of the species lies safely - but solely - protected within the years' eggs, glued firmly to the underside of tree branches.  It's a system that's worked for thousands of years.  I can only hope and trust that nothing disrupts it in the future....