May 29, 2009 at 11:02 am (botany, ecology)
Tags: Amur honeysuckle, Armoria rusticana, beauty, black medick, Cerastium vulgatum, common wood sorrel, Convolvulus arvensis, dame's rocket, Duchesnea indica, field bindweed, Hesperis matronalis, horse radish, Indian strawberry, life history strategy, Lonicera maackii, Lychnis alba, Mayslake, Medicago lupulina, mouse-ear chickweed, Oxalis stricta, phenology, Trifolium repens, weed, white campion, white clover
by Carl Strang
I have fallen way behind in reporting on new wildflowers at Mayslake, which I am tracking to begin phenology records for that preserve. Today I want to feature weeds. This is a term I use with care, as it has several distinctly different meanings. In everyday use a weed is simply an undesirable plant. To a restoration specialist they are not native to the local landscape. If they are good competitors, a special effort is needed to remove them. If not, they simply will be pushed aside by native plants as the latter get established. To an ecologist, “weedy” organisms can be plants or animals, and are defined by their life history strategy. In comparison to other organisms they have short lives, grow quickly in disturbed habitats where there is little competition (weeds are poor competitors), and produce large numbers of small seeds or young that can disperse widely. One or more of these definitions apply to the plants I am sharing today, and I am trying to use photos that reveal their beauty . So, let’s begin with dame’s rocket.
I have found it in only one corner of the preserve, near the friary, but as you can see it is abundant in that spot. In the cracked pavement around the friary I found this field bindweed.
Its flowers place it in the morning glory family. One of the friary’s abandoned gardens has some horse radish growing, and that patch may be the source of a few plants growing more than 100 yards away, near the parking lot for the off-leash dog area.
Other weedy plants can be found in lawns around the main parking lots and mansion. They include white clover,
and mouse-ear chickweed.
Amur honeysuckle is a bane of our woodlands, but it has a beautiful floral display this time of year.
I admit to confusion in the white flowering members of the genera Silene and Lychnis, but believe I have the identification correct for this white campion, or evening lychnis, L. alba.
Common wood sorrel is regarded as native, but it certainly has a weedy life history strategy.
Finally there is the Indian strawberry, named for its origin in south Asia and the small red fruits that resemble strawberries but are inedible.
The leaves also bear a resemblance to our native wild strawberry, but the yellow flowers are a giveaway.
A final note is to thank Scott N. again for his assistance, this time with the field cress. Once that former mystery plant started elongating its fruiting stalk it became, to my eye, less beautiful and mysterious, but much more recognizable.
May 28, 2009 at 11:13 am (dragonflies and damselflies, insects (other))
Tags: Bombus fervidus, Bombus impatiens, cabbage white, Colias eurytheme, common whitetail, Danaus plexippus, eastern comma, eastern forktail, insect migration, Ischnura verticalis, Libellula lydia, Mayslake, monarch, mourning cloak, Nymphalis antiopa, orange sulfur, Pieris rapae, Polygonia comma, Xylocopa virginica
by Carl Strang
Large insects are beginning to appear at Mayslake Forest Preserve. For some weeks I have been seeing mourning cloaks, which overwintered as adults.
The above photo I took at Fullersburg last year. Another butterfly that overwinters as an adult is the eastern comma. This one at Mayslake apparently had a close call, probably with a bird. Note the missing section from the left hind wing.
There have been some orange sulfurs, which overwintered in the pupal stage.
Their close relatives the cabbage whites have been common all over the preserve. Earlier I celebrated the arrival of the first common green darner dragonflies, migrants from the South. The first locally emerging dragonfly I saw was this male common whitetail at Mayslake last week.
He is recognizable to species and gender by his wing pattern, but he has newly emerged and so still has the immature coloration on his abdomen. The first mature Mayslake damselflies were eastern forktails.
The above photo of a mature male is from a few years ago, I believe at Songbird Slough, but this is our most common and widely distributed damselfly.
I have not had good luck photographing bumblebee queens this spring. Bombus impatiens has been common, and I saw one Bombus fervidus near the friary on May 22, at the same honeysuckle bush that hosted two of these:
This is the large carpenter bee Xylocopa virginica.
The first monarch butterfly arrived at Mayslake this week.
This individual is too clean to have made the trip all the way to Mexico and back. It is an offspring of those that wintered down there, made part of the journey back north, and laid their eggs on milkweed plants they found in the southwestern U.S. I shake my head in amazement at the instincts that guide these insects, with their pinhead brains, through journeys last made by their great grandparents.
May 27, 2009 at 11:15 am (botany, restoration)
by Carl Strang
In mid-May I returned to my garlic mustard study plots to harvest the second year plants, counting the survivors in each square-meter subplot to learn what had happened. The second year plants had developed flower buds,
Meanwhile the seedlings were adding leaves.
When the time came to count and remove second year plants, the contrast between treated and control square-meters was clear cut beyond expectation.
The plant count on untreated (control) squares ranged 100-223 per square meter, with a median value of 159. In some of the treated squares I had uprooted all of the second year plants I could see in March. A few remained in May, probably ones that were so small in March that I mistook them for seedlings. Their numbers ranged 1-4 on the square-meter subplots, with a median of 3. I was most interested in the other treatment, in which I pinched or clipped plants at ground level, leaving the roots. There had been indications in the literature that this would be sufficient to kill the plants. Such was not entirely the case here.
Some clipped plants had enough stem buried beneath the ground that they recovered and their new shoots were producing fruits. Their numbers were much lower than in the controls, but also distinctly greater than in the pulled plant treatment: range of 21-47, median of 23. These differences were statistically significant. Clipping in March killed most but not all plants.
I also was interested in seedlings. The claim has been made that uprooting plants disturbs the soil and so increases the number of seedlings. Seedling numbers increased between March and April in control squares as well as in both treatment types, but there was no statistically significant difference among the three different square types. I will need to return next year to see if there is a difference then, but so far I find no support for the claim that uprooting garlic mustard has undesirable effects.
On the other hand, when I removed the second-year plants in May, I saw that seedlings in treatment squares were robust and healthy looking.
In contrast, the ones in control squares were puny.
Clearly they had been suppressed by the second year plants. Time will tell if they catch up with the ones in the treatment squares.
I will want to see if the ground-level clipping of control plants in May succeeded in killing them. Also, next year I am thinking of applying the initial treatments in April rather than in March, and doing the clip treatment at a more realistic level of a short distance above the ground.
May 26, 2009 at 10:56 am (birds, methods)
Tags: bur oak, Mayslake, nest, nest finding, Quercus macrocarpa, robin, white-breasted nuthatch
by Carl Strang
A few days ago I pointed to one method of finding bird nests: watching birds carrying nest material. Another way is to watch birds carrying food.
I found a robin nest at Mayslake this past week by noticing an adult carrying a worm in its beak, and hearing the cries of the begging babies in the nest. After the parent left I took a quick peek at the nest in a small pine tree.
Minimizing my disturbance, I took a quick photo and left, and within moments one of the parents was back at the nest stuffing another hungry mouth. The same method revealed the savanna white-breasted nuthatch nest. Both parent birds flew to the same spot on the far side of a large bur oak trunk, one of them clearly carrying food. The nest cavity proved to be a knothole.
Nuthatches don’t have the excavating capabilities of woodpeckers, but they can use cavities they discover, removing bits of rotten wood to open them up. They are very secretive, fledging the young early in the morning and taking them some distance from the nest. I seldom have seen fledglings, and hope to be more successful this time.
May 25, 2009 at 11:15 am (botany, restoration)
Tags: brush removal, common dewberry, controlled burn, Cornus stolonifera, Geranium maculatum, Hydrophyllum virginianum, Mayslake, oak, red-osier dogwood, restoration, Rubus flagellaris, Virginia waterleaf, wild geranium
by Carl Strang
In earlier posts I have written about the restoration work going on at Mayslake Forest Preserve. Today I want to share some of the positive results that already are visible. The prairie was burned in late March, and as usual looked like a desolate moonscape afterward.
This week that same area is green with vigorous growth.
Meanwhile, the slope between the friary and May’s Lake has greened with diverse plants.
In places there are abundant oak seedlings, the potential next generation that had no chance beneath the dense buckthorn and honeysuckle brush that was cleared out over the winter. Members of both the white and red oak groups are visible here.
In addition, Virginia waterleaf is flowering in good numbers all along the slope.
Toward the bottom of the hill some wild geraniums have begun to bloom.
Nearby are some Rubus which key out to common dewberry.
A red-osier dogwood was one of the woody plants carefully avoided by the brush-clearing crew, and it is flowering.
Earlier I showed the abundant trout lilies, toothworts, three species of buttercups, dutchman’s breeches, trilliums, violets, wood anemones and so forth. More will follow.
May 22, 2009 at 10:59 am (botany)
Tags: bulbous cress, Cardamine bulbosa, Culver, honeysuckle, Lonicera, seedling, skunk cabbage, Symplocarpus foetidus
by Carl Strang
I paid a quick visit to Culver, Indiana, over the weekend, and had a few minutes to visit my mystery seedling. It has been largely overtopped by skunk cabbages.
You may see it as a tiny plant between the big skunk cabbage leaves in the middle of the photo. Here it is close up.
I continue to think shrub, and took a look at the nearby shrubs, seeking a match. One possibility was this:
Though this candidate and the seedling continue to remind me of the bush honeysuckles, these were not flowering, and their bark was not the shredded wheat pattern of the Lonicera I know.
The leaves also show more width toward the tip than I am accustomed to seeing in honeysuckles.
On a related point, the cress I mentioned in earlier posts was flowering on May 16, and proved indeed to be bulbous cress as Scott N. suggested.
The late blooming date, white flowers and habitat are conclusive.
May 21, 2009 at 11:08 am (methods)
Tags: bioblitz, Indiana dunes
by Carl Strang
The dominant story line of this blog has been my discovery, bit by bit, of the natural history of Mayslake Forest Preserve in DuPage County, Illinois. I hope it is clear that this is a dynamic story, with drama, comedy, and above all, daily change. As often as I go out, though, I am getting only a snapshot. As the months and years pass my understanding will continue to grow. I hope also that you are inspired to look anew at your own favorite outdoor places.
Last Friday I took the opportunity to check out a different but equally legitimate approach to understanding a place. I visited the Bioblitz camp at Indiana Dunes National Lakeshore.
A bioblitz in its original form is an assembly of scientists who compile a list of all the species they can find in some defined area during a 24-hour period. Students and volunteers support the scientists and participate in data collection. The event is organized to maximize public education, with biodiversity (life’s variety) the central concept.
The advantages of this approach are the technical expertise of the recruited scientists, the assembly of a significant body of data (with the possibility that species new to the target area and even new to science may be discovered), and the spectacle of the event. But there are disadvantages and limitations, too. The main help I could have offered would have been with singing insects, but that would only be effective if the bioblitz had been scheduled in late summer or early autumn. Many other groups of insects likewise have not appeared or matured, yet. On the other hand, a late summer date would have missed many species whose appearance is limited to spring. Another disadvantage in this case was the weather.
The kickoff was noon on Friday. Rain poured all day. I visited in the early afternoon, when busloads of schoolchildren still filled the headquarters area. They enjoyed splashing in puddles, and gleefully filled their water bottles from the puddles. Though they no doubt were cautioned not to drink that water, I think the concrete connection between the concepts of rain and drinking water made for good education.
Of course, the species tally had not really begun that early in the game. A news article soon after the 24 hours ended mentioned that many specimens remained to be identified, but 939 species had been named to that point, with vascular plants leading the way at 525. The insect count of 214 is sure to grow by a lot in coming days. Vertebrate counts were 11 mammals, 117 birds, 27 reptiles and amphibians, and 18 fish. Fungi were represented by 27 species.
Despite the rain, spirits were high on Friday. This approach can be modified in many ways. The area of study could be much smaller, say, a yard, or a schoolyard, or a park. There could be a series of seasonal bioblitzes, or the list of species could be accumulated as they are found through the year. Most conspicuous species are common enough to be found in field guides or through Internet resources, so specialist scientists are not needed for a school study. Biodiversity is an important concept, and worth exploring through first hand experience.
May 20, 2009 at 11:00 am (singing insects)
Tags: fall field cricket, Fullersburg, Gryllus pennsylvanicus, Gryllus veletis, spring field cricket
by Carl Strang
When I started my study of singing insects, I already was familiar with field crickets, the common black chirpers whose song most people find pleasant (you can find recordings here or here). As I reviewed the literature I was surprised to find that there are two species of them in our part of the country, the spring field cricket and the fall field cricket. These are what biologists call sibling species. They are practically identical in almost every respect, and yet they do not interbreed and so are separate species.
Both are black, the same size and shape, and have indistinguishable songs. The songs, by the way, as in all the singing insects, are produced by the males. The females follow the songs to find mates. What distinguishes the spring and fall species apparently is their season. Spring field crickets mature early. In previous years I have noted first songs on 28 May 2006, 12 May 2007, and 31 May 2008. This year I heard a few in Marshall County, Indiana, on May 16, and one in DuPage County, Illinois, on May 18. In July their singing tails off as they complete their breeding, lay their eggs, and die. There doesn’t seem to be a completely song-free gap, though singers are very few in the middle of July. By the end of that month the number of field cricket songs is increasing rapidly, and we have entered the reproductive season for the fall field cricket. That season extends into the fall. The last song dates I have noted were 20 October 2006, 17 October 2007, and 4 November 2008. Very few are to be heard by October, however.
Spring field cricket eggs hatch early enough for them to begin growing in the late summer and fall. Fall field cricket eggs reportedly wait until spring to hatch. Each species has a 1-year lifespan, but they are offset as I have described.
Field crickets sing day and night, though I have not yet measured whether there are variations in how much they sing at different times. They don’t always occur together. For instance, I have never heard a spring field cricket in my home neighborhood, nor have I found any at Fullersburg Woods Forest Preserve, though I have heard fall field crickets in both locations. Both spring and fall field crickets are common; I have found each species at 21 northeast Illinois locations (mainly DuPage County) so far, though both species occurred together at only 13 locations. Both occur in woodlands and meadows, but the spring species seldom ventures into lawns as the fall field cricket does. Both also are comfortable around human structures.
May 19, 2009 at 11:04 am (birds, methods)
Tags: Baltimore oriole, bur oak, Mayslake, nest, nest finding, Quercus macrocarpa, savanna
by Carl Strang
One way to find a bird nest is to notice a bird carrying nest material, and watch where it goes. If you stay quiet and are far enough away that the bird is not alarmed, this can lead you to a nest under construction. This was how I found the nest of Mayslake’s north savanna pair of Baltimore orioles.
This nest was among the highest twigs in a bur oak. Though it has the classical hanging basket shape, it is not suspended over a stream or trail as is commonly the case. Nevertheless, its location in the outermost extremity of a branch makes it difficult for a climbing predator to find and to reach. The female is the nest builder, but I haven’t managed to get close enough to her for a photograph. I showed the male of this pair a few days ago, and here he is again.
At least one more pair of this species is nesting on the preserve this year. I should mention here that it is best to stay away from the nest as a general rule at least until incubation is well under way. In the early stages the birds haven’t invested so much, and can be quick to abandon the nest if disturbed.
May 18, 2009 at 11:00 am (mammals)
Tags: cottontail, Mayslake, nest
by Carl Strang
Earlier I described a cottontail mother’s behavior in covering her nest. It appeared that the babies inside were newborns on April 29. I stayed away from the nest until May 4, when a check showed the nest to be less well hidden than is typical.
The muddy soil that the mother had excavated caused the adjacent area to contrast significantly with the lawn, and the mix of fur and grass likewise was easy to detect. On May 7 I was late in arriving at Mayslake, and found that the mowing already had been done. The top had been whisked off the nest.
Six young were in there, and none were injured, but a seventh had been pulled out of the nest and killed by the mower. I covered the nest. On May 12 I found the nest uncovered again.
The cottontail youngsters appeared to be approaching independence, but only two weeks had passed after the time I thought they were born. They should be in the nest for three. They were starting to look a little shaggy, but their ears were not standing up completely. The following day was rainy and stormy. Early the morning of May 14 I found the nest empty.
There are many possibilities here. All I can say for certain is that I saw no baby cottontails nearby, alive or dead. The most positive possibility for this bunch of youngsters is that they were weaned, and left the nest to begin their independent lives. Rabbits learn none of their skills from their mother. When she decides to wean them, she simply stops coming to the nest. Eventually hunger drives the little rabbits to leave the nest and, guided by instinct, they start learning which plants are good to eat.