September 30, 2013

Ohio Orchids 5

More orchids! What fun it was this summer to check out these interesting and beautiful plants. With the help of some very knowledgeable friends, we've been pretty successful at finding them. It really helps to understand what habitat they prefer and when they are likely to bloom. In a couple of cases, we had all the correct information and saw the plants but this year these populations did not bloom, which is really not surprising where orchids are concerned. 

Quite a bit of energy is required for a plant to produce a flower. Orchids are able to store energy in underground structures until they have enough energy and conditions are just right for blooming. Some have flowers every year but many only bloom every few years and instead only produce leaves, or have no above-ground presence at all. This is especially true for those species that grow in deep shade.

Here are the strap-like leaves of the Tubercled Rein Orchid (Platanthera flava), part of a large population at a nature preserve in western Ohio. 

There were hundreds of plants and not a single bloom all summer! Friends reported that last year was a great year to see this population in bloom, so it is probably not surprising that this year was an "energy storage" year. We were able to see its green flower stalks in bloom in West Virginia, though:

Another similar story was our experience with the Pad Leaf Orchid (Platanthera orbiculata). Its two large round leaves are unmistakeable, and we saw plenty of them on a foray to northern Ohio, but once again we couldn't find any that had flower stalks. We saw several, though on our early July trip to West Virginia, and despite their greenish color we thought they were spectacular.

Here is a closer photo--individual flowers look like flying angels!

We had much better luck in Ohio on lots of others though, and some were really stunning. In July we visited a very wet area in the southeastern part of the state that had all sorts of interesting plants, including the Purple Fringeless Orchid (Platanthera peramoena). Here is a photo of its habitat and you can see how wet it was. 

This plant likes lots of water, and we saw several in bloom in a roadside ditch as well as in a more natural wetland. The size of the flower stalks varied quite a bit, and here is one of the largest:

One of my favorites is also a wetland specialist and we saw it in a nature preserve near Springfield. It is the Prairie Fringed Orchid (Platanthera leucophae), and it is considered to be threatened by the U.S. Fish and Wildlife Service. 

Habitat loss is the main reason that its status is tenuous; collection of the plants and use of pesticides which kill the hawkmoths that pollinate it are other threats. What a shame it would be if this plant did not continue to do well here in Ohio and across its range.

Here is a tiny orchid that grows in the wet forest or other wet areas and is quite easily missed by the casual hiker. It is called the Club Spur or Green Woodland Orchid (Platanthera clavellata) Interestingly, it is self-pollinating, but insects do visit the flowers. It is relatively uncommon in Ohio but it does occur at Cedar Bog.

Next is arguably the most common orchid in our state: the Downy Rattlesnake Plantain (Goodyera pubescens). One of the easiest to identify, it has evergreen basal leaves that have a beautiful net-like pattern:

Here is a closer look at the lovely but tiny flowers. 

It is commonly found in forested areas with acid soils.

Last but not least (for this post anyway) is the gorgeous but tiny Three Birds Orchid (Triphora trianthophora). Its name reflects the plant's tendency to have a trio of blooms:

This orchid blooms in mid-August, when most wildflower activity is in sunny prairies and meadows. It favors mature beech-maple forests, and it doesn't bloom every year in this deep shade. Often it has no above-ground growth, but is still living underground as tuberoids. Populations bloom synchronously, that is all individuals bloom at about the same time, with each flower lasting just about a day. Some flowers have a distinct pinkish tinge:

We saw a lovely population of these orchids at one of the local metro parks, and we were joined by an Ohio State botany professor who is quite interested in this species. He said that it is likely that the plant is "on its way" to heterotrophy--that is, to depending on outside sources such as fungi for energy. It can live for years underground with no sun exposure at all, and when it does come up it just has a very tiny leaf. Photosynthesis probably cannot account for all of its energy input. I'm not sure what advantage this is to the plant, but I sure find evolutionary biology to be fascinating!

That is enough for now--and I still haven't shown you the ladies' tresses! More about those orchids in a future post.

September 20, 2013

Addendum to the Cat Post!

This week we've seen and photographed some more cool caterpillars and a couple of things seemed worthy of posting. 

In my last blog entry I showed several swallowtail caterpillars: Black, Spicebush, Giant and Pipevine. One of the most interesting things about swallowtail cats is that when disturbed, they extrude (I think that "evert" is actually the proper term) a weird  fork-shaped organ from their head that not only looks scary but smells terrible--I told you it was weird!  This defensive organ is called the osmeterium, and the foul-smelling compounds vary from species to species. 

Until this week we had never seen this, but the other day we got a few shots of a very annoyed Black Swallowtail caterpillar. Here is a series of pictures, showing the caterpillar going from placid to really mad:

A bird or other predator not only gets the scary visual, but gets a whiff of really bad smelling chemicals.

The same day when we were out at Siebenthaler Fen we finally saw the caterpillar of the Eastern Tiger Swallowtail. A sharp-eyed friend that we were with spotted it on an ash leaflet, and the color of the caterpillar perfectly matched the color of the leaflet. Eastern Tiger Swallowtails are relatively common, but we had never seen the larva. Talk about a strange looking animal!

That eyespot is just a marking and not its actual eye. In contrast to the other swallowtails, Eastern Tiger Swallowtails feed on a wide variety of plants, including tuliptree, ash, and wild black cherry and several others. Earlier instars of this caterpillar are bird-dropping mimics, while this later form is thought to resemble a snake. In any event, I'm glad we were able to see and photograph it. I sort of wish we had been able to see it evert its osmeterium, but repeated photographs were probably enough disturbance for one day!

September 14, 2013

It's Cat Season!

Caterpillar season, that is. September marks the end of summer, but a bonus is that a lot of large and showy caterpillars are out and about. Some are very hard to find because they have many ways of hiding, but we have been fortunate to be out with folks who are very good at spotting them. I'm trying to get better at it--the key is recognizing their host plants and then searching with a critical eye along stems and leaves.

Caterpillars are present in all the warm months, of course. They are the mainstay of the diet of young songbirds. We associate many birds with seed-intensive diets, but they also need protein, particularly when the nestlings are developing. In fact, one source that I saw says that a single pair of chickadees must find 6000 to 9000 caterpillars to raise one clutch of young. 

A Preachy Aside: Reread that last sentence, and think about whether that chickadee family is going to do well in a yard with a lot of lawn and a few exotic shrubs, chosen because "nothing eats them". We NEED to plant native trees, shrubs and wildflowers in our suburban gardens to support these critters, if we want them (and us) to survive in a world of increasingly shrinking and fragmented natural habitat. I'll give that reference again here--read it and then get and read Doug Tallamy's book Bringing Nature Home, available here and probably at your library. He was the featured speaker at the Midwest Native Plant Conference and has a very compelling message! 

Anyway--we have been exploring a lot this summer, and particularly in the past few weeks we have spotted some pretty cool cats. Caterpillars go through several molts or instars, and later instars may look totally different from earlier ones, making identification a bit challenging. The whole metamorphosis process, especially what goes on in a chrysalis or coccoon, is mind boggling. This tubular, worm-like eating machine completely changes in every way to a winged flier able to reproduce itself. Here is a gallery of nine of these amazing critters!

First up is the Pipevine Swallowtail. The caterpillar ranges from red to black, with lots of pointy projections. The adult is stunning, with its metallic blue hindwings. The caterpillars feed on members of the Aristolochia or birthwort family--here in Ohio that mainly means wild ginger and Dutchman's Pipe, which has the odd-looking flower shown below in the upper left. 

The Spicebush Swallowtail has one of the strangest looking caterpillars, and if you were a hungry bird you would think twice about eating this fierce-looking creature. It feeds on spicebush and sassafrass, both pretty common shrubs or small trees here in Ohio, and they are great plants for the garden, too. In the caterpillar photo you can see some web-like material on the leaf. This is silk that is produced by the caterpillar to draw together leaf edges, making a sort of bivouac in which to hide during the day as an added protection against predators. Many caterpillars are most actively out and about feeding at night and they hide during the day.

Another caterpillar that hides in a self-made leafy shelter is the Silver-spotted Skipper. It is pretty common in suburban gardens, and is one of the easiest skippers to identify. The caterpillar feeds on a wide variety of plants in the legume family including Black Locust, Honeylocust and many others. Silver-spotted Skippers overwinter as a chrysalis and the adults feed on a variety of flowers, but rarely on yellow ones!

Baltimore Checkerspot is one of our most beautiful butterflies. In contrast to the Silver-spotted Skipper, the caterpillar has very specific food requirements at certain points in its development; it needs Turtlehead (pictured in the lower left corner below) which occurs in wet meadows and creeksides. The young caterpillars cluster on the plants, creating a web shelter for protection.  You can see some of the webbing in the corner of the caterpillar photo. When they are larger they leave the shelter and can feed on other plants. Most chrysalises are quite camouflaged and very hard to find; the Baltimore Checkerspot chrysalis is tiny but stunning (see the inset photo in the upper right of the caterpillar photo).

Plant some fennel or dill in your garden and you are likely to attract the beautiful Black Swallowtail. They feed on a variety of members of the carrot family as well as on an interesting plant called Garden Rue (Ruta graveolens). This rue has blue-green leaves and yellow flowers and I'm going to try to find some for next year for my garden. Black swallowtails overwinter as a chrysalis. The adult in this photo is a female; the males don't have the blue on the hindwing. 

Most of us are quite familiar with the Monarch and its dependence on various members of the milkweed family of plants. Its caterpillars consume distasteful chemicals from the milkweed which protect them from bird predation. 

Monarchs are interesting in that they are migratory; all eastern monarchs head for a small mountainous area of central Mexico in the fall. This area has been subject to logging and weather stress, and despite some protection monarchs are extremely vulnerable on their wintering grounds. Adding to their trouble is the fact that the milkweed that they depend on in the north is getting more and more scarce, thanks to widespread use of herbicides following the advent of Roundup-ready corn and soybeans.

So plant milkweed in your garden! Common Milkweed (Asclepias syriaca) is kind of a coarse plant but certainly can do quite well in a suburban garden. There are many other members of the family that are quite showy, like Butterflyweed (A. tuberosa) and Rose or Swamp Milkweed (A. incarnata).

What do you suppose those things are on the Wafer Ash tree in the photo below? It looks like a couple of birds have relieved themselves right on the leaves. 

In fact, these are Giant Swallowtail caterpillars! Birds avoid eating bird droppings, so looking like one is a useful defense. Many other organisms utilize this strategy including some spiders, some moths, and some other butterflies.

The Giant Swallowtail is our largest butterfly here in Ohio, and it feeds pretty exclusively on members of the citrus family. Surprised? Yes, we have some wild citrus plants here in Ohio, namely Wafer Ash or Hoptree (Ptelea trifoliata), and Prickly Ash (Xanthoxylum americanum). Neither is an ash and neither produces edible fruit, but both are small trees that can do well in home landscapes. In the deep south, Giant Swallowtail caterpillars can be agricultural pests on the citrus crops, but here in Ohio we don't have that problem!

Another bird-dropping mimic is the Viceroy caterpillar. The caterpillars feed on plants in the willow family, including willows, poplars and cottonwoods. The adult was thought to be a mimic, looking much like the bad-tasting monarch, but lately they are believed to be toxic themselves due to the fact that they sequester salicylic acid in their bodies from their host plants, which makes them unpalatable to predators. 

Last but not least is the Cloudless Sulphur. This cat feeds mainly on plants in the genus Senna and it is mostly a southern butterfly. Typically, Cloudless Sulphurs are seen in Ohio in late summer, when they disperse from their southern breeding grounds. There is plenty of senna to support their caterpillars, but the cats probably are unable to survive northern winters.

Caterpillars are pretty amazing, given the way they have developed chemical, behavioral and visual strategies to avoid predation, and probably use other means of which we unaware. This is just a very brief introduction to the caterpillar world and I haven't even touched on moth caterpillars which greatly outnumber those of butterflies. I'll have to save that for a future post!

For more about caterpillars, go over to Ohio Birds and Biodiversity at this link and check out Caterpillars of Eastern North America by David L. Wagner.

September 9, 2013

Ohio Orchids 4

This morning a friend asked why she hadn't been getting any notices about my blog--uh--probably because I haven't posted anything lately! I've been out and about and have seen so much and I haven't made time for sitting at the computer. Add in hosting a wonderful family reunion and some travel and...well, those are my excuses anyway! I'm back, though, and I know I need to catch up on some promised posts.

This has been a glorious summer for wildflowers, thanks to all the rain that we have gotten. Their diversity of form, color and habitat preference never ceases to amaze me. This diversity is quite well illustrated by the wonderful variety of terrestrial orchids that we have here in Ohio, and Bill and I have continued to make a point of seeing as many of them as possible this summer. As I said in my previous orchid posts, some are stunning and some are inconspicuous, but all are interesting and many are uncommon to rare.

I'll start with the beautiful Small Purple Fringed Orchid (Platanthera psycodes), which we saw in the shadowy woods along the boardwalk at Cedar Bog in June. It inhabits a variety of moist habitats, such as stream and river banks, roadside ditches, and moist meadows, but it is not common at all in Ohio. Butterflies and a variety of diurnal and nocturnal moths are responsible for pollinating the flowers.

Also growing at Cedar Bog in June is the gorgeous Grass Pink (Calopogon tuberosus).

This orchid flower is kind of "upside down" compared to most. Most orchid flowers rotate during development so that their "lip", which is often fringed, ridged  or colorful to attract insects is at the bottom of the flower. In this case, however, the "lip" remains above and the column, which contains the reproductive structures, is below. If a bee lands on the hairs of the upper lip, the lip will swing down under the weight of the insect, and the pollen will be deposited on the bee's back. Off it will go to another flower and transfer the pollen. I like this view of a cluster of flowers:

I'm not sure that there is much more stunning than the Yellow Fringed Orchid (Plantanthera ciliaris).

It has a very unusual distribution in Ohio, occurring in the northwest corner near Toledo and in the very southern part of the state:

Ohio County Distributional Map for Platanthera ciliaris

We saw it in both areas; interestingly it bloomed earlier in the north than in the south. Speculation as to why there are these very separated populations has to do with ancient rivers and glaciation. Yellow Fringed Orchids are considered to be "butterfly specialists" because they attract and are pollinated by butterflies, not surprising given the long, nectar-containing spur. I loved the near-symmetry of this view from above:

Some Ohio orchids have no chlorophyll; they receive all their energy from a complex interrelationship with fungi, many of which in turn may have nutritional connections to trees. Crested Coralroot (Hexalectris spicata) is a prime example of this, and it occurs on alkaline soils in rocky woodlands and forested streambanks. 

We spotted this individual in Adams County in July on a very rainy day which enabled the colors of this plant to really show beautifully. I'm not sure if the insect on the right side was looking to pollinate the plant or just to hide from the rain!

July brought both the showiest and perhaps the least conspicuous orchids! Here is the latter, the Green Adder's Mouth (Malaxis unifolia). 

Blooming at Wahkeena Nature Preserve, this plant was no more than 5 inches high. Easily overlooked because it is completely green, it is unmistakably an orchid with its parallel-veined leaf and the typical flower structure of three sepals and 3 petals, with one petal modified to form a tiny "lip."

I think that one of my favorite orchids this summer was another one that has no showy color, the Cranefly Orchid (Tipularia discolor). I love the way the flowers look like flying insects along the stalk:

Like the Puttyroot Orchid that I mentioned in a previous post, the Cranefly Orchid produces a single leaf in the fall that persists above the leaf litter through the winter, storing energy below the ground: 

The leaf disappears in the spring, and the plant only blooms when it has enough energy to do so, which may not be every summer. It grows in shady forest and can be quite difficult to spot. 

I have some more orchids to share but they will have to wait for another post!