Early Autumn Woodland Flowers

by Carl Strang

We’re turning for home in this first season of inventorying the forbs of Mayslake Forest Preserve. First flowering dates of spring- and summer-blooming plants are safely in the record for comparison to future years. Today’s installment of woodland species has a distinctly late-season quality to it. Nothing announces the end of summer better than the goldenrods. Elm-leaved goldenrod is abundant in both the north and the south units of Mayslake’s savanna.

Elm-leaved goldenrod 2b

I’ll feature tall goldenrod here, though this species has such a broad ecological range that I could have included it among the prairie plants as well.

Tall goldenrod b

Late boneset can grow in open places, though at Mayslake I am finding it best represented in the north savanna.

Late boneset 2b

While most members of genus Rudbeckia are associated with meadows and prairies, the brown-eyed Susan is a woodland species.

Brown-eyed Susan b

One of my favorites in the autumn woodlands is wingstem, and I was happy to find some growing at Mayslake.

Wingstem 2b

The only species in today’s group that is not in the sunflower family is the woodland knotweed.

Woodland knotweed 1b

While this plant can be very abundant in forests, I have found only a relatively small number in Mayslake’s savannas.

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Forbes’s Tree Cricket

by Carl Strang

DuPage County is one of the few documented places where Forbes’s tree cricket occurs. That is not because it is particularly rare. It probably is quite widespread and common. The problem is that at present the only way to identify a tree cricket as a Forbes’s is to measure the number of pulses per second in its song (which is a long, nonstop, fairly loud trill). Forbes’s tree cricket is a sibling species of the better known black-horned tree cricket. In fact, where both are known to occur together the only way to distinguish them is by song pulse rate.

Black-horned or Forbes's 2b

Sibling species don’t interbreed, but visually are indistinguishable or nearly so. Black-horned and Forbes’s tree crickets are able to avoid interbreeding because the different pulse rates are recognized by females, who approach only males with the correct song for their kind. Sibling species are a recurring theme in all our major groups of singing insects: crickets, katydids and cicadas. That fact underlines the importance of song as opposed to visual recognition in these groups.

Black-horned or Forbes's male 1c b

You can’t distinguish their songs by ear; we’re talking about pulse rates that can approach 90 per second on a warm day. I use my home studio equipment to slow the recorded song, step by step, until the pulses are countable.

Forbes’s tree cricket was recognized as a species by Thomas J. Walker of the University of Florida, who runs the Singing Insects of North America website . As far as I know he has not published this distinction outside that website, but in his 1963 monograph The nigricornis Group of the Genus Oecanthus  he showed data that demonstrate black-horned tree crickets have two very distinct song pulse rates. With further study after that publication he concluded that these were in fact being produced by separate, sibling species. The “fast-trilling nigricornis” now is labeled Oecanthus forbesi, Forbes’s tree cricket.

These two species are distinguished from other tree crickets by being relatively dark, though they are quite variable and individuals at the paler end of the spectrum have to be studied with a hand lens focused on the pattern of spots on the two basal antenna segments (partially visible in the photo below).

Black-horned or Forbes's male 1a b

These two species prefer prairies or meadows with lots of forbs (flowering herbs other than grasses, sedges and the like), though some sing from vines or shrubs within such meadows. Given their recent recognition as separate species, little is known about their variability and possibly distinct habitat preferences. It is painstaking work, as you have seen, but in coming years I hope to build a database on this species pair in DuPage County. In my limited study so far I have found black-horned tree crickets at Blackwell Forest Preserve, and Forbes’s at Danada Forest Preserve and Tri-County/James Pate Phillips State Park.

Another Round of Weeds

by Carl Strang

Late summer’s fade into early autumn brings out more weeds in the botanical parade that I have shared from Mayslake Forest Preserve this year. Weeds as defined in this blog are generally plants that are annuals or biennials, grow fast in disturbed places, produce a lot of seeds, then die. I also include non-native and undesirable plants in this category. Thus far, it has been easy to show that weeds can be beautiful. This time I am a little pressed to do so, as today’s collection is showiness challenged.

Common ragweed b

This, for instance, is common ragweed. It is wind-pollinated, so rather than investing in colorful petals or other animal attractants it produces huge volumes of tiny, non-sticky pollen to drift on the breezes and fertilize large numbers of seeds. People with pollen allergies suffer as a result. We have two ragweeds, the other being giant ragweed:

Giant ragweed b

Earlier in the season we met three fleabane varieties common at Mayslake. Much less conspicuous because of its tiny flowers is the fourth species in genus Erigeron, horseweed.

Horseweed b

Here is an example of the confusion that can result from the use of common names for plants. Two vastly different forbs are known as “fireweed.” The one at Mayslake is a member of genus Erechtites in the sunflower family.

Fireweed 2b

I have attempted to accommodate botanically astute friends who question my use of common names in the blog by listing the scientific names in the tags at the head of the blog entry. People in the know will have no trouble figuring out which scientific name goes with which common name. I use the names in Swink & Wilhelm’s Plants of the Chicago Region.

Here and there at Mayslake are scattered common burdock plants.

Common burdock b

Their flowers also can be purple. Finally, I am indulging myself by including stickseed in the “weeds” category, though it more properly is a woodland species.

Stickseed b

Though this is a native plant, there are moments when I am pulling its incredibly grabby seeds from my clothing that I unambiguously regard stickseed as an undesirable.

Common Meadow Katydid

by Carl Strang

Earlier  I related my error in previously identifying DuPage County’s abundant, early-season large meadow katydid as the common meadow katydid, Orchelimum vulgare. This spring I discovered that the correct ID is the gladiator meadow katydid, O. gladiator. It turns out that the two are physically very similar, and there seemed to be some ambiguity in reference recordings of their songs. Last week I was at Meacham Grove Forest Preserve, mainly in search of late season Pachyschelus beetles, about which more will be forthcoming this fall or winter. Reaching Meacham’s west woods requires a walk across the meadow- and wetland-dominated eastern part of the preserve. Where the trail crossed the preserve lake’s inlet stream, I heard rattling buzzes that sounded like the songs of gladiators. This required some investigation, as gladiators elsewhere had finished singing weeks earlier. I found one, and it proved indeed to be a gladiator. But farther along the trail, approaching the pedestrian bridge over Bloomingdale Road, I heard a different song. This was a loud, tick-and-buzz Orchelimum song, but the ticks were more spaced and the buzz was very tight, making it distinct from the songs both of the gladiators I had just heard, and of the black-legged meadow katydids that also had been singing along the stream. This insect was in a dry meadow, singing from the exposed top of a sweet clover plant.

Common meadow katydid 2b

I photographed him, recorded his song, and then reluctantly collected him. He proved to be a common meadow katydid. The cerci, or reproductive claspers, are distinct from those of the gladiator and just like those in reference drawings for the common. The differences are, however, subtle enough under high magnification that I could not have confirmed them on the live insect. Another difference is the shape of the pronotum, the cape-like structure that covers the top and sides of the thorax. Here is the one on the common meadow katydid,

Common meadow katydid cropped 2b

and here is the one on the gladiator meadow katydid.

Gladiator cropped 3b

Again the differences are subtle, but the side of the gladiator’s pronotum has a simple, uniformly rounded outline with no major zigzags or kinks. That of the common meadow katydid has several turns or bends at the front, bottom and (especially) back edges. Incidentally, there is no mistaking a black-legged meadow katydid for either of the others if you see one:

Black-legged meadow katydid 2b

The best news out of all this is that the songs of these three large meadow katydids of DuPage County’s grasslands and wetlands are distinguishable. The gladiator’s buzz is a long, relatively slow rattling sound, with or without a few preceding ticks. The black-legged meadow katydid has a shorter buzz, of a similar sound quality but distinctly faster, always preceded by 2-4 ticks that are rapid, evenly spaced, and run straight into the buzz. Often, ticks and buzzes alternate in a continuous flow. In my limited experience since first finding the common meadow katydid at Meacham, I have noticed two variations in their songs. The buzz can be very tight and fast, reminiscent of Roesel’s katydid . In that variation the song is very different from both the gladiator and the black-leg. However, some individuals (perhaps ones singing at a lower temperature) have a slower buzz that to my ear is just like that of the black-leg. Confusion is prevented by attending to the ticks. In both common meadow katydid song variations, the ticks are irregularly spaced, farther apart, and more numerous than in the black-leg’s song.

For recordings that may help make these differences clear, check out the Songs of Insects and the Singing Insects of North America websites.

Meet Conrad

by Carl Strang

From the start of this blog, I have sung the praises of the restoration work that has been ongoing for many years at Mayslake Forest Preserve. The time is well past due for recognizing the person primarily responsible for that success: Conrad Fialkowski.

Conrad b

Recently I had the opportunity to watch Conrad in action. Mayslake was one of the hosts for a camp called Outdoor Explorers. The week-long, cooperative program brought children from four communities out to four forest preserves on a rotating basis. The children were selected for their limited opportunity to experience the outdoors (one boy asked me if there were any bears to worry about). One of their activities at Mayslake was to remove buckthorn and honeysuckle brush from a woodland, first step in its restoration. Conrad was masterful in his direction of this activity. The kids enjoyed wielding loppers and bow saws, and thanks to Conrad this was done safely and effectively. Conrad was especially effective in his recognition and support of the individual talents in each child. Here he poses with one of the groups of kids and their park district counselors in front of the mountain of brush they had cut.

Conrad & group 1b

But this is only the first step in the process. Much work remains for Conrad and co-steward Jacqui Gleason (who we’ll meet later; she joined Conrad in this effort three years ago). Those two volunteers put in many hours of difficult labor per week year round. They will need to keep the brush stumps from resprouting, and plant seeds to hold the ground gained through the kids’ effort. One of Conrad’s many secrets is the effectiveness of bottlebrush grass in preventing erosion and resisting the invasion of undesirable plants in the early stages of woodland restoration at Mayslake.

Bottlebrush grass b

I have been getting a lot of compliments about the flower photos in this blog. You can thank Conrad and Jacqui for those plants’ having the opportunity to grow at Mayslake Forest Preserve.

Bumblebee Dynamics

by Carl Strang

In my last update on bumblebees  at Mayslake Forest Preserve I described the 5 species I had observed to that point. In the subsequent few weeks there have been a couple of changes to report. First is the apparent addition of a 6th species.

Bombus pennsylvanicus 1b

I believe this to be Bombus pennsylvanicus. At first glance it is very close to Bombus auricomus, which I described earlier. Both are relatively large bumblebees, both have lots of black on the thorax (especially on the sides), and both have segments 2 and 3 of the abdomen all yellow. However, auricomus has a cleaner, sharper look. All the yellow areas are bright, pure yellow. The black areas are unblemished by hairs of other colors. Both black and yellow areas are sharply defined, and correspond to the edges of body segments. If I am correct in my identification, pennsylvanicus has a muddier look. The yellow of the dorsal abdomen spills a little onto the first segment as you can just see in the above photo. Also, the yellow area of the posterior dorsal thorax has some black hairs mixed in, and the black on the sides of the thorax has some yellow hairs mixed in.

The more astonishing change is the nearly total disappearance of Bombus bimaculatus over the past three weeks. Through July, this was the most common bumblebee at Mayslake, with numbers exceeding those of all other species combined. I was away a week for Roger Raccoon Club , and returned to find the bimaculatus nearly gone. Now I see at most one or two a day. The other common small species, Bombus impatiens, continues essentially unchanged.

Bombus impatiens worker b

This is my first year of following the bumblebees at Mayslake. I don’t know if this disappearance is usual, and I don’t know what it means. I doubt that the species has a limited season, as bumblebees generally continue through the summer. Some of the native, solitary bees are specific to a single flower species and thus have defined seasons, but bumblebees are generalists. They are known to monitor changes in flower abundance and to travel miles, and so may have abandoned Mayslake for an abundant appearance of other flowers elsewhere. Disease might have impacted one colony, but for all the local colonies to be affected with no obvious change in other species seems unlikely (though the uncommon Bombus griseocollis also has been absent in August).

One day earlier this week I saw a couple odd looking bumblebees that seemed clumsy on the flowers.

Bombus bimaculatus or griseocollis male b

Their markings were like those of griseocollis or bimaculatus, not precisely fitting either. They had enormous eyes, and were larger than most workers of either species. Photos showed them also to have unusually long antennae. These are males. What, if anything, their sudden appearance has to do with the absence of their species’ workers is another piece of the puzzle that needs fitting.

Block Counts

by Carl Strang

Sometimes I collect data without a particular question in mind, on the possibility that I may learn something that guides a future inquiry. My block counts of singing insects are an example.

Block count 1b

My mailbox is a block away from my home. When the singing insect season arrives in the latter half of July, I begin going around the block the long way to retrieve my mail. The above photo shows the first side of the block as I head north. Next, I turn the corner and head west.

Block count 2b

I vary the starting time, record that along with date and temperature, and count the number of individuals of each singing insect species I hear along the way. Here is the view as I turn south.

Block count 3b

This neighborhood may not look like much, but I have heard a total of 14 species here from 2007 to date, including field crickets, bush crickets, trigs, ground crickets, tree crickets, true katydids, false katydids and cicadas. These data allow me to get some understanding of how species vary in numbers between years, and how their singing changes over the season and with time of day. Once I have picked up the mail, here is the final block as I turn to home.

Block count 4b

One pattern I would have missed without the discipline of the block count is a pause in singing among the cicadas in late afternoon, followed by a big push as light fades toward dusk. I have documented the arrival of a new species, the jumping bush cricket, in the neighborhood. Striped ground crickets and greater anglewing katydids were the most abundant singers in 2007, but while the stripeds also were the top species in 2008 there was a big drop in numbers of singing anglewings. It’s a little early to say much about 2009, but so far there seem to be more Carolina ground crickets than in the previous two years.

Some Wetland Plants

by Carl Strang

To this point in the season I have included wetland plants with prairie plants in my accounts of species flowering at Mayslake Forest Preserve. This time I’ll feature them separately. It has been a while since the common cattails flowered.

Cattail b

Their seeds are ripening now. Though elderberry can occur in woodlands, at Mayslake this shrub grows mainly in wetlands.

Elderberry 1b

The pink and white flowers of swamp milkweed are my favorites in genus Asclepias.

Swamp milkweed 2b

Spotted Joe Pye weed is a wetland plant that superficially resembles its woodland relative, purple Joe Pye weed.

Spotted joe-pye weed b

A less conspicuous wetland species is the common water horehound.

Common water horehound b

Most buttercups bloom early in the season. An exception is the bristly buttercup.

Bristly buttercup b

Two of the knotweeds recently began to bloom along the stream: Lady’s thumb

Lady's thumb 2b

and smartweed.

Smartweed 1b

Late summer brings hummingbirds, gradually making their way south. Among the flowers that especially appeal to them, being red and tubular in shape, is the cardinal flower.

Cardinal flower 2b

Finally, here is the first of the late season beggar’s ticks group, the bur marigold.

Bur marigold b

And that brings us up to date.

Nesting Season Ending

by Carl Strang

The end of the nesting season for birds has arrived. The cowbirds at Mayslake Forest Preserve have shaken out the last of their eggs, and the fledglings have matured.

Cowbird older fledgling b

Song sparrows, chipping sparrows, and phoebes were among the last foster parents. The phoebes, as far as I can tell, raised only cowbirds in their two nestings at Mayslake this year. Better news was a brood of bluebirds, produced in one of the bird houses adjacent to the mansion grounds.

Bluebird fledge 1b

Indigo buntings continued to sing and nest well into the season.

Indigo bunting 2b

But the latest nester of all, for which I have no photo at this time, is the goldfinch. Goldfinches have a diet entirely of seeds, and take advantage of the abundant seed production at the end of the season to raise their young in late July and August.

Late Summer Prairie Wildflowers

by Carl Strang

The long season of the prairies’ floral displays continues at Mayslake Forest Preserve. In my first year there I am inventorying species and recording first flowering dates for future comparisons. We’ll begin with some goldenrods. The Missouri goldenrod blooms in late July, like the similar early goldenrod of Mayslake’s savanna.

Missouri goldenrod b

August adds the dissimilar grass-leaved goldenrod,

Grass-leaved goldenrod b

and stiff goldenrod,

Stiff goldenrod 1b

both of which grow abundantly at Mayslake.

Three species tower above most of the other prairie plants. One of them, the tall coreopsis, has relatively small, abundant flower heads.

Tall coreopsis 1b

Earlier  we met the compass plant. A close relative is prairie dock.

Prairie dock 3b

A third species in genus Silphium, though not as tall as the others, is rosin weed.

Rosin weed b

Though many of the prairie flowers appearing in this part of the season have yellow blooms, we also see the purple of Missouri ironweed.

Missouri ironweed b

New England aster is just getting under way, and will extend its flowering period into autumn.

New England aster b

The false sunflower does not appear to be as abundant at Mayslake as in some other preserves.

False sunflower 2b

Finally, here are the odd looking flowers of common gaura, a member of the evening primrose family.

Common gaura 2b

All too soon we’ll be entering the autumn chapter of this story.

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