Happy hour at the mint bar

A naturalist outlook

By Albert Cardona, January 25th, 2020.

In the Autumn of 2018 we bought a small mint plant from the grocery store, whose leaves my son and I would pluck occasionally to make doogh: half volume of yogurt or kefir, half of sparkling water, and the mint. In a pot by the bay window, the plant was slowly forgotten--yet watered--among the orchids. At some point in November, the grim look of its nearly leafless stalks suggested the end of its yield, and, not wanting to trash a living being, I planted it outside in the yard and forgot about it.

Great black digger wasp Sphex pensylvanicus

Fast forward to March 2019, after much snow and many freezing nights--Northern Virginia endures strong Winters despite its Southern latitude--, the little mint plant that could was hanging in there. Its now horizontal stalks had developed roots, and new leaves and shoots were growing upwards from them. Small as it was, I mostly only noticed it again when I mulched its patch a few weeks later. At this point I didn't even know whether mint was a plant sturdy enough to survive extended freezing temperatures.

By the Summer, the mint was reaching over 2 feet high and was now a sprawling bush perhaps 4 feet wide. And it bloomed. And what a wonder that it beecame.

Humped beewolf Philanthus gibbosus

Over the course of 8 weeks in the Summer of 2019 I photographed dozens of species of Hymenoptera (bees and wasps), as well as many other insects, including beetles, flies, mosquitoes, moths and butterflies, true bugs and more, all of them taking a sip of nectar at the mint bar--or hunting those who did, such as spiders. My camera: an iPhone SE, equipped with a clip-on macro lens, and lots of patience--and a good hat: in full sun, photographs turned out crisper and more detailed. And my companion, the iNaturalist app (backed by the California Academy of Sciences and the National Geographic Society) with its brilliant automatic species identification system [1].

In all, I found 17 species of bees (including a cuckoo bee), 11 of wasps, 13 of butterflies and moths, 8 of bugs, 7 of flies, 2 of mosquitoes, 3 of beetles, 1 of crickets and 1 of spiders, all on the mint bush at different times of the day and night. An astounding animal diversity drinking nectar from and contributing to pollinating a single mint bush! Given the biological deserts that are grass lawns in suburban America, this one accidental mint bush may have sustained entire populations of insects over the Summer period, thanks to the progressively maturing yet abundant and long-lasting mint flowers. With the widely publicized massive reduction in the number of insects of any species throughout the world, well documented in Germany [2], any initiative--even my accidental one--to provide support for insect populations must be encouraged. I was very pleased to see that King's college in Cambridge, UK, is converting one of its iconic lawns into a meadow, to foster the growth of wild flowers and support insect populations and other animals and plants that depend on them.

Orthoneyra fly

Watering the bush every evening became a favorite occupation of mine. After dinner and already dark, a hand-held diffuse LED lamp helped me observe nocturnal visitors such as Anopheles and Ochlerotatus mosquitoes, lucerne moths and the--to me--unusual long-necked seed bugs.

I didn't even know there were so many kinds of bees. From the tiny green and golden jewel-like sweat bees to the smallish, strippy leaf-cutter bees and nimble carpenter bees, to the unexpected cuckoo bees, then honey bees, followed by the larger bumble bees and the very large Eastern carpenter bees (the latter was never seen on the mint, rather, on a nearby butterfly bush). And the wasps dazzled me with their formidably colored and proportioned bodies, displaying a range of diversity of forms and shapes and textures (don't miss the humped beewolf wasp) that makes me appreciate more the scientific finding that Hymenoptera--thanks to parasitic wasps--are perhaps the most species-rich group of animals on the planet, even beating the Coleoptera (beetles), many of which are parasitized by wasps.

This single mint bush provided me with a natural entomology and behavioral ecology classroom. From when do bees and wasps first come out of their nests in the morning, or when they go home for the night before sunset, to whether they are solitary (e.g. cuckoo bees, humped beewolf wasps) or forage in groups (blue-winged scoliid wasps, and of course bumble bees and honey bees). A swarm of over twenty blue-winged scoliid wasps, their large and colorfull bodies all moving their majestic dark wings as they walked around mint flowers sipping nectar, was quite the sight. And the remains of some scoliid wasps indicated that some--perhaps hornets, seen hunting and dining on monarch butterflies 10 feet away from the mint bush--were on the look out to make supper out of distracted individuals. And did you know that some bees may fight ants? Witness the dead body of an ant, its mandibles still clasping the leg of an otherwise happily foraging modest masked bee. A natural tag, this dead ant allowed me to recognize this particular bee over multiple days.

Modest masked bee Hylaeus modestus with a dead ant clasping its leg

Modest masked bee Hylaeus modestus with a dead ant clasping its leg; second sighting

Now, in Cambridge, UK, I found myself with a plundered mint plant in my hands, so guess what I did. Results to be seen in the Summer.

The photographic harvest from a single mint bush over the Summer of 2020 in Northern Virginia, hosted by the iNaturalist online database:

  1. Bees
  2. Wasps
    • Blue-winged scoliid wasp, Scolia dubia [1] [2] [3 predated upon]
    • Double-banded scoliid wasp, Scolia bicincta [1] [2]
    • Mexican grass-carrying wasp, Isodontia mexicana [1] [2] [3] [4] [5]
    • Katydid wasp, Sphex nudus [1]
    • Great black wasp, Sphex pensylvanicus [1]
    • Four-toothed mason wasp, Monobia quadridens [1]
    • Widow yellowjacket wasp, Vespula vidua [1]
    • Genus Hoplitimyia [1]
    • Common eastern Physocephala wasp, Physocephala tibialis [1] [2] [3]
    • Great golden digger wasp, Sphex ichneumoneus [1]
    • Stinging wasp of the Vespidae family, Euodynerus megaera [1]
  3. Butterflies and moths
    • Ailanthus webworm moth, Atteva aurea [1] [2]
    • Lucerne moth Nomophila nearctica [1]
    • Common angle moth Macaria aemulataria [1] [2]
    • Genus Pleuroprucha [1]
    • Silver-spotted skipper butterfly Epargyreus clarus [1]
    • Common buckeye butterfly Junonia coenia [1]
    • Gray hairstreak moth Strymon melinus [1]
    • Caterpillar of cutworm moths and allies, family Noctuidae [1]
    • Caterpillar of moth from genus Trichoplusia [1]
    • Orange mint moth Pyrausta orphisalis [1]
    • Caterpillar of owlet moths and allies, superfamily Noctuoidea [1]
    • Caterpillar of a moth from the genus Synchlora [1]
    • Cabbage white butterfly Pieris rapae [1]
  4. True bugs
    • Twice-stabbed sting bug, Cosmopepla lintneriana [1] [2]
    • Tarnished plant bug, Lygus lineolaris [1] [2]
    • Long-necked seed bug, Myodocha serripes [1] [1]
    • True bug from the suborder Heteroptera [1]
    • Tribe Mirini [1]
    • Genus Neurocolpus [1] [2]
    • Genus Niesthrea [1]
    • Spittlebug, superfamily Cercopoidea [1]
  5. Flies and mosquitoes
    • Thick-legged hover fly, Syritta pipiens [1 in flight] [2] [3]
    • Tiger crane fly, genus Nephrotoma [1]
    • Common greenbottle fly, Lucilia sericata [1]
    • Sarcophaga fly [1]
    • Secondary screwworm fly Cochliomyia macellaria [1]
    • Fly with patterend eyes, genus Orthonevra [1]
    • Bot flies, blow flies, and allies, superfamily Oestroidea [1]
    • Asian rock pool mosquito Ochlerotatus japonicus [1]
    • Mosquito, Anopheles punctipennis [1]
  6. Beetles
    • Spotted lady beetle, Coleomegilla maculata [1]
    • Spotted cucumber beetle Diabrotica undecimpunctata [1]
    • Unidentified small bettle [1]
  7. Crickets
    • Red-headed bush cricket Phyllopalpus pulchellus [1]
  8. Spiders
    • Goldenrod crab spider Misumena vatia [1]

Notes

  1. If the iNaturalist automatic identification system didn't exist and I would have had to browse through a binary key to search for the correct genus or species, I doubt I would have found the time. The mere idea of it brings back fond memories of my undergrad years, at a zoology lab demonstration, flipping through a book containing a classification of fishes in binary key written in Italian, where the alternative choice was almost always "non come sopra" ("not like the above"). These words in Italian and the look and smell of dead fishes in formol or alcohol jars has stayed with me forever.
  2. "More than 75 percent decline over 27 years in total flying insect biomass in protected areas". Hallmann et al. 2017 PLoS ONE [link].