Sunday, July 28, 2024

Hairy Elephant's Foot, A Surprising Pollinator Magnet

At least until you get to know them well, there are some plants that are hard to get excited about.  Often that's because they don't have fascinating foliage or stunning flowers.  Just because a plant isn't classically beautiful, though, that doesn't mean it isn't greatly loved by pollinators and other insects.


Frankly, Hairy Elephant's Foot (Elephantopus tomentosus) is just such a plant.  It is a hard plant to photograph well.  For the first few months of spring and summer, it consists of a few large, hairy leaves lying flat on the ground, all coming from a central point.  Not glamorous, but definitely easy to photograph.

It's in July that the trouble begins.  The plants start to put up their flowering stalks, which rise for 12-15" above the basal leaves.  There is hardly any foliage on these stems at all.  At the top of each stalk, sudden branches stick out awkwardly, each crowned with a trio of small, bright green, hairy, pointy "leaves".  Nestled within those bracts, the small, lavender flowers open, dainty and subtle.  They open in the morning and close in mid afternoon.


These delicate little blooms wash out readily in a photo, especially in any bright light.   Their dainty airiness just looks sparse on "film", even though it looks charming en masse in real life.

A great plant for shade, Hairy Elephant's Foot grows well there, although it tends to be rather widely scattered.  Unexpectedly last year, I had an experiment in our yard when a neighbor cut down several large trees right near our joint property line and turned what had been almost complete shade into full sun, for 5-6 hours each day.

I expected the shade-loving understory plants that grew in that area to frazzle and die, which many of them did.  The Hairy Elephant's Foot, however, had a banner year, blooming prolifically and attracting an amazing number of pollinators and other insects - 21 different species that I was able to photograph!

So how do I best share the amazing number and diversity of insects that I observed?  A simple list, even illustrated with photos and spiced with bits of (hopefully) interesting information, seems overwhelming and ultimately boring.  So I thought I would talk about a few of the "categories" of insects that I observed:  1) Butterflies and Skippers, 2) Pest Control Squad - Solitary Wasps and Syrphid Flies, 3) A Predator and Prey Duo, 4) Native Bees - Pollinators Extraordinaire, 5) Flies, and 6) Passersby.

Two of the species I photographed using Hairy Elephant's Foot last summer are considered somewhat rare or threatened:  the American Bumble Bee and the Yellow-thighed Thick-leg Fly, a form of syrphid fly.  Both are shown below in their appropriate categories.


BUTTERFLIES AND SKIPPERS:

It's always fun to start with "the pretties" - and I've come to think of butterflies and skippers as "flying flowers", the prettiest group of insects overall.

Butterflies and skippers (and moths) are more than just pretty, though.  Their caterpillars are, according to Dr. Doug Tallamy, one of the primary ways that energy, captured by plants from the sun, moves up the food chain.  EVERYTHING seems to eat caterpillars.  For those of us who are birders, that's especially true of most of the songbirds, 95% of whom raise their young on insects, especially caterpillars.  

So in feeding adult butterflies and skippers, Hairy Elephant's Foot is also helping to keep those adults in our yard, thus supporting the production of caterpillars to feed the upcoming generation of birds and other animals here.



Eastern Tiger Swallowtail (Papilio glaucus), 8/19/23.   With a variety of host plants in the Magnolia and the Rose families, Eastern Tiger Swallowtails are fairly common across a wide range in North America.  In our yard, I'm guessing that they usually spend their larval time on Tulip Poplars, since we have several extremely large specimens of that majestic tree.  It's often easy to overlook the fact that trees can serve as important host and pollinator plants.



Zebra Swallowtail (Eurytides marcellus), 8/19/23).  If you don't have pawpaws, you won't have Zebra Swallowtails.  Our neighborhood has a plethora of pawpaws, in great part because deer don't like it and so it spreads with little competition in our deer-challenged yards.  Consequently, we have a plethora of zebra swallowtails.  Most of the time, these ethereal beauties are just floating through, but Hairy Elephant's Foot got them to stick around for a bit.



Common Buckeye (Junonia coenia), 8/20/23.  This was the first time I had seen a Common Buckeye in our yard.  I've started planting Carolina Petunias (Ruellia caroliniensis) as a "matrix plant" and it turns out that they, along with plantains, are host plants for Common Buckeye caterpillars, along with several other species.  So, was it a coincidence to see this one last summer, a year or two after I started adding Carolina Petunias to the yard?  Or the result of adding yet another native plant species to the local plantscape?


Silver-spotted Skipper (Epargyreus clarus), 8/23/23.  If you look very closely, you can also see a little crab spider under the flowers to the right of the skipper.  The caterpillars of Silver-spotted Skippers feed on many plants in the pea family, from Wisteria to Tick-trefoils, where they build a shelter with silk.  According to iNaturalist, it's unusual to see this species visiting yellow flowers;  they prefer blue, pink, red, purple and even white blooms.


Wavy-lined Emerald Moth caterpillar (Synchlora aerata), 8/23/23.  This is the only species of butterfly or skipper (or moth) that I have seen using Hairy Elephant's Foot as a host plant.  These little guys camouflage themselves by sticking pieces of the flower they are eating to their bodies, so this one has purple bits pasted to it, but the same species will have bright yellow bits on one of the Rudbeckias, white bits on Mountain Mint, etc.  Many times, it's hard to see the caterpillar body at all!  The adult moth is a very pretty light emerald green with wavy lines, as suggested by its name.

Other butterflies that I've observed nectarting on Hairy Elephant's Foot include the Sleepy Orange (Abaeis nicippe) and the Cabbage White (Pieris rapae).  Other skippers that I've observed include Horace's Duskywing (Erynnis horatius), Common Checkered Skipper (Burnsius communis), and Zabulon Skipper (Lon zabulon).


PEST CONTROL SQUAD - SOLITARY WASPS:

Wasps seem scary to many of us, but it's literally a few "bad apples" that have spoiled the barrel of public opinion.  Social wasps (paper wasps and yellowjackets) live in colonies, which they defend vigorously.  Solitary wasps, on the other hand, build nests by themselves and are not at all aggressive.  They will only sting if you attempt to catch them in your bare hands.  I have not observed any social wasps using Hairy Elephant's Foot, but I've observed several solitary wasp species doing so.

All wasps raise their larvae (their "babies") on meat, usually on paralyzed insects, sometimes on paralyzed spiders, and (for social wasps) on chewed up insects.  Because they raise their young on other insects and on spiders, wasps are important predators in our yards and gardens, helping to keep the populations of other species in balance and under control.

Solitary wasps paralyze various species of insect or spider and then lay an egg on the paralyzed prey.   Each different species of wasp preys on a different species of insect or spider.  After being paralyzed, the prey animal lives and provides fresh food for the larva when the wasp egg hatches.  Gruesome, to my mind, but very effective.


Double-banded Scoliid Wasp (Scolia bicincta), 8/20/23.  Scoliid wasps are scarab beetle predators, digging for beetle larvae (a.k.a. grubs) in the soil, paralyzing them, and laying an egg on each.  When the egg hatches, the wasp larva eats the beetle larva, then pupates in the host body.   These wasps are excellent grub control!  About 10 years ago, when we lived in south-central Kansas, I did an entire blog post on this species:  http://gaiagarden.blogspot.com/2014/08/double-banded-scoliid-wasp.html



Blue-winged Scoliid Wasp (Scolia dubia), 8/20/23.  Isn't this a cool looking wasp?!  I had never seen this interesting looking species before last summer.  As a scoliid wasp, it is another species that preys on scarab beetle larvae (white grubs), like the Double-banded Scoliid Wasp above.  It is thought that these species may also parasitize Japanese beetle larvae!  


Gold-marked Thread-waisted Wasp (Eremnophila aureonotata), 8/21-3/23.  I've always wondered how anything - food, blood, etc. - gets through that narrow waist!  Anyway, this interesting looking solitary wasp preys on larger moth larvae, like those of the sphinx moths and owlet & cutworm moths, for food for its larvae.


Fraternal Potter Wasp (Eumenes fraternus), 8/20/23.  There's a reason this little wasp is called a "potter wasp" - the female builds a gorgeous little mud pot in which she stashes the caterpillars that she paralyzes for her young to eat.  She then lays an egg and closes the pot, also with mud, making a perfect little nursery.



Weevil Wasp (Cerceris halone), 8/23/23.  Another solitary wasp, this wasp provisions the cells in her nursery burrows with paralyzed weevils from the genus Curculio.


A PREDATOR AND PREY DUO:

There are bees known as "cuckoo bees" that parasitize the nests of other bees.  Often this happens by the cuckoo bee following the female of its host species back to her nest.  When the host female departs for another load of pollen and nectar to provision her latest brood cell, the female cuckoo bee quickly ducks in and lays an egg.  Generally, when the egg of the cuckoo bee hatches, it either attacks and kills the larva of the host bee, or it hatches first and eats the egg of the host bee before it hatches.  Either way, the cuckoo bee larva then eats the provisions that the mother host bee stored for her own offspring, pupates, and emerges the following year in place of the young of the host bee.

The relationship between the host bee and the cuckoo bee is often very specific, with each cuckoo bee parasitizing only a single species.

How does the cuckoo bee find the host bee?  Well, she hangs out at the same "bar", so to speak.  The life cycles of the host bee and the cuckoo bee are perfectly timed to overlap, and both will be found nectaring at the same flowers.  I found such a pair using the blooms of Hairy Elephant's Foot in our yard:  the Two-spotted Longhorn Bee (host) and the Lunate Longhorn-cuckoo Bee (parasite).



Two-spotted Longhorn Bee (Melissodes bimaculatus), 8/20/23 - host bee.  This almost pure black bee gets its name from the two squarish white spots on either side of its abdomen.  Unfortunately, you can't see those field marks in this photo.



Lunate Longhorn-cuckoo Bee (Triepeolus lunatus), 8/20/23 - cuckoo bee (parasite).


NATIVE BEES - POLLINATORS EXTRAORDINAIRE:

More people are understanding the importance of our native bees for pollination.  The beloved Honey Bee is actually a European import, brought here by colonists who unsurprisingly wanted the honey it produced, as well as its pollination services.  But, for all we hear about honey bees pollinating plants, they are not as efficient at the job as many of our native bees are.

Before the European colonists arrived, there was no problem with pollination in North America.  This continent has almost 4000 species of native bees, often with life cycles exquisitely timed to coincide with those of the plant they evolved to partner with.  Some of these native bees are generalist pollinators, others are specialists who only pollinate one single species, still others pollinate the flowers of just a few plants.

I have not seen honey bees use Hairy Elephant's Foot, although that certainly doesn't mean they don't.  The bees I've seen pollinating this plant all fall under the heading of generalist native bees.  I'll start with two different bumble bee species.....



American Bumble Bee (Bombus pensylvanicus), 8/23/23.  According to iNaturalist, this species used to be one of the most common types of bumble bee, especially in the south, but 90% of its population has been lost in the last 20 years.  It is now considered threatened throughout much of its range.



Common Eastern Bumble Bee (Bombus impatiens), 8/20/23.  As its name implies, this is the bumble bee that I see most commonly in our yard.



Eastern Carpenter Bee (Xylocopa virginica), 8/20/23.  What looks like a bumble bee but has a smooth abdomen?  A carpenter bee.  Great pollinators, they do NOT eat wood...although they do tunnel into it to make their solitary nests.  The females will reuse existing nest tunnels, only taking the time and energy to excavate new tunnels when absolutely necessary.



Pure Green Sweat Bee (Augochlora pura), 8/20/23.  This beautiful little bee nests in rotting logs, a habitat that we have been restoring on our property.  The fertilized females also overwinter underneath rotting logs, waiting until it's time for them to emerge in the spring.


FLIES:

Many flies act as pollinators, although they are not as well known in that role as bees are.  The first species I share here is one of the relatively rare species I've seen on Hairy Elephant's Foot.



Yellow-thighed Thick-leg Fly (Tropidia albistylum), 8/23/23.  This is a relatively rare species of syrphid fly with a very unattractive common name.  As of this writing, there are only 212 observations of this species in iNaturalist, as opposed to 25,000-50,000 observations of two more common syrphid fly species that I've seen in our yard.



Greenbottle Fly (Lucilia sp.), 8/20/23.  This genus of flies (I can't identify this photo below that level) are scavengers, generally speaking.

There were at least 2 other species of flies that I photographed on Hairy Elephant's Foot, but I was unable to identify either of them further.


PASSERSBY:

Of course, in watching any plant or area, there will be some insects that just happen to perch for a while.  Rounding out this line-up of Hairy Elephant's Foot insect fans are a couple of those more incidental visitors....



Blue Dasher (Pachydiplax longipennis), 8/22/23.  This is a dimorphic species, meaning that the male and female look dissimilar.  This individual is a female;  it is the male that has the blue coloration for which the species is named.  Dragonflies are fierce predators of smaller insects.  I'm always hoping the ones I see are living up to their colloquial name of "mosquito hawks".



Eastern Tailed Blue butterflies (Cupido comyntas)  - and a Midge (7/30/23).   Hairy Elephant's Foot can even be used for a bit of canoodling, with or without a voyeuristic midge looking on.

In conclusion, Hairy Elephant's Foot is not a classically "beautiful" plant, but it sure packs a powerful punch for wildlife.  Including insects I've seen but not photographed, I've noticed over 30 different species using this plant - and the deer don't bother it at all.  If you can find a corner somewhere, I highly recommend it.  I've never seen Hairy Elephant's Foot "in the trade", but personal experience tells me that it transplants well.  Mine just showed up on their own.  Keep your eyes peeled or ask if anyone you know has some they'd be willing to share.  You'll be glad you did.  

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