Enough has been written about Danaus plexippus on the internet (including here on my blog in previous years). Here are a few pictures I really like.
Next in the series of posts on composite flowers lacking ray florets is blue mistflower. Like the joe-pye weeds, blue mistflower was once placed in the genus Eupatorium, but nowadays it’s known as Conoclinium coelestinum. The flowers are somewhat similar in appearance to joe-pyes, the heads of tightly clustered disk florets with long protruding styles giving the inflorescences a fine, feathery, misty look.
Also like joe-pye weeds, blue mistflower likes wet soils; along the banks of the Potomac River, if I see joe-pyes, I’m almost certain to find blue mistflower nearby. Unlike joe-pyes, the plants are short, getting to about two feet tall in ideal conditions.
Speaking of the Potomac, I went back out to check on the spot I reported on last week, a place where in other years I would definitely find mistflower. It was all underwater again. Lots of rain upstream.
Blue mistflower ranges mostly along the Mississippi River basin and its tributaries, from southern Illinois south, and also in the eastern mid-Atlantic and the Carolinas. It’s found in most of Maryland except for the westernmost and easternmost parts of the state.
Apparently these flowers are a great nectar source for a variety of butterflies, but I haven’t seen many on it. Three years ago I wrote that I was worried that the blue mistflowers in my garden would become weedy*. “Weedy” is, of course, in the eye of the gardener. They certainly have spread, somewhat aggressively, and I’ve had to pull some out, but they haven’t reached weed status yet.
While shooting eastern tiger swallowtails in the joe-pye weeds, out of the corner of my eye I kept seeing something large and white darting about in the New York ironweed. I only managed to get a few blurry pictures of it before it disappeared altogether. There’s no doubt what it was: a zebra swallowtail (Protographium marcellus, formerly Eurytides marcellus).
The next day I was outside tending to something else when I saw it again. This time I dashed inside, got the camera, and dashed back outside to the low fence that separates my property from the road. Along this fence I’ve planted understory trees and shrubs, and a few perennials. Among these are two small pawpaws, and that’s where the zebra swallowtail was.
For half an hour I observed its behavior. It would flutter about the pawpaws, settling for maybe a second or two at a time, then it would head south and check out the joe-pyes and ironweeds, then it would make a big loop up the street and come back over the fence on the north side of the yard, gliding back through the trees and shrubs to flutter about the pawpaws again. Sometimes it made a big loop through my yard instead; always it returned to the pawpaws.
The males are known to patrol around pawpaws, looking for females. Pawpaws (Asimina triloba) are the host plant for the caterpillars. Adult zebra swallowtails feed on nectar from a variety of plants, including dogbane, common milkweed, verbena, redbud, and blueberry. I need to plant some of those by next spring, because I sure would like to see more of these striking insects flying about my yard.
Zebra swallowtails are found primarily in the South, southern mid-Atlantic, and southern mid-West. In Maryland, which is almost as far north as they go, they fly in April and August; further south they fly from March to December.
Apparently it’s difficult to distinguish the females from the males, at least when they’re on the wing, other than by observing behavior. The one pictured in this post might be a male; all the time I observed it, I never saw it laying eggs (the females lay one egg at a time, on the undersides of pawpaw leaves). I also haven’t seen any eggs or caterpillars on the plants, though I’ve been checking every day.
Zebra swallowtails from summer broods have much longer tails than those from spring broods. Click on these pictures to get a better look at just how long those tails are.
ps: here’s a picture of a pawpaw flower; around here, they bloom from about mid April to mid May
Like the joe-pye species, the inflorescence of NY ironweed consists only of disk florets; there are no rays at all. And what a great example of this kind of flower it is: look closely and you can see how five narrow petals, fused at the base, form a corolla, from which a split style pops way out.
There are two native species in MD; the other one, broad-leaved ironweed (V. glauca), is found in a few locations in the eastern Piedmont and in the Coastal Plain, while New York ironweed is found throughout the state. There’s also an alien, Arkansas ironweed (V. arkansana) reported in one location in the Coastal Plain.
New York ironweed’s native range is from southern New England into northern Florida and west into central Kentucky and Tennessee (and in one county way out in northern New Mexico). It’s listed “special concern” in Kentucky and “presumed extirpated” in Ohio.
Often described as “coarse” in texture, this is a tall forb – over six feet in ideal conditions – with an open habit. It likes moist to wet soils; in the wild you’ll find it growing along river banks, in the full sun or dappled shade.
In the garden site it where it will get enough sun and water, in the back since it gets so tall, or along a fence. It doesn’t attract butterflies as well as the joe-pye weeds do, but bees go crazy for it. And it blooms for a long time.
I was trying to get good, clear close-up shots of the flowers, with the camera mounted on a tripod, but something large and white kept moving around in the upper reaches of the plants. As soon as I realized what it was I took the camera in hand and tried to get pictures of yet another type of butterfly. It never stayed still, so all the shots were lousy and I was pretty bummed… until the next day. More about that in my next post.
While researching butterflies I learned that there are six dark-winged swallowtail species in Maryland: the black, giant, palamedes, pipevine, spicebush, and dark morph eastern tiger.
The dark winged butterfly that I had been shooting on joe-pye weeds [see previous post] was a dark morph eastern tiger swallowtail (Papilio glaucus). The dark morphs are always females.
Several characteristics distinguish dark morphs from other butterflies with dark wings, but the one that’s a dead giveaway is the lack of white spots on the body.
Also note that the white marks on the trailing edge of the forewing are elongated: dashes rather than spots.
It wasn’t until the next day, while I was shooting yet another species of butterfly (subject of a future post), that I saw what I thought was a spicebush swallowtail (Papilio troilus). I didn’t even realize at the time that’s what it was, because I was so focused on the other one that I didn’t stop to think that this particular butterfly was actually resting on a spicebush.
Note the round spots on the body, and also the fingertip-shaped bluish markings at the trailing edge of the hindwing. The lack of a lighter patch in front of those blue marks indicates that this is a female. SEE UPDATE BELOW.
Spicebush swallowtails range from eastern Texas north into the Midwest and southern New England, and south into Florida. Several species of plants host the caterpillars, most notably spicebush (Lindera benzoin). Adults feed on quite a few different plant species, including some exotics; among the native species are milkweeds, dogbanes, and thistles.
I’m totally kicking myself for not hopping the fence that was in my way to get better pictures. I’ve checked my spicebushes several times each day since then, but haven’t seen another butterfly on them.
Here’s a giant swallowtail (Papilio cresphontes) that I photographed in the eastern panhandle of West Virginia a few years ago. I’ve never seen one of these around my house; they are found in most of Maryland, but are fairly rare.
I believe this last one to be a pipevine swallowtail (Battus philenor). The plants it’s on are Aristolochia fimbriata, white-veined Dutchman’s pipe, a South American species that’s growing in the Enid A. Haupt Garden next to the Freer Gallery of Art in Washington, DC. Aristolochia species are hosts for the pipevine swallowtail, and so the gardeners in the Haupt and the nearby Mary Livingston Ripley Garden have been growing them for several years now, in order to attract the butterflies. Smithsonian Gardens has some wonderful spaces around the Mall, but I’m digressing.
UPDATE 8/22/18: The second butterfly is NOT a spicebush swallowtail. I failed to see something obvious. Pictured is the almost-identical red-spotted purple (Limenitis arthemis).
I checked many resources for help understanding butterfly identification; particularly useful sites included