After the spring beauties broke winter’s long suppression of wildflowers, other plants quickly have begun to bloom at Mayslake Forest Preserve.
Bloodroot is a popular subject for nature photographers. Seed-carrying ants have been spreading this species in several directions from one initial colony in the south savanna.
Bloodroot is one of many plants in several families which convergently have evolved little edible handles called elaiosomes on their seeds. The ants carry the seeds to their nests, and after consuming the elaiosomes discard (plant) the seeds.
Dutchman’s breeches likewise are spreading impressively from their starting point.
The year’s earliest sedge to bloom on the preserve, the common oak sedge, also is flowering, here surrounded by white trout lilies and cutleaf toothworts.
The trout lilies and toothworts are flowering now, along with common blue violets and others. So far these few species are pointing to an average to slightly early year as measured by flower phenology at Mayslake.
Last week, Nikki Dahlin and I found a black plastic bag blown up against the base of a tree at Mayslake Forest Preserve. We were going to throw it away, but Nikki noticed something.
A polyphemus moth caterpillar had pupated against the bag. Normally its secretions would simply cement its wraparound dead leaf, but here the bag was attached as well.
A dilemma. I decided to compromise, cutting away and properly disposing of the bulk of the bag, but returning the bit of plastic with the cocoon to the ground, as shown in the photo. Technically that makes me a litterbug, but I intend to return periodically to check, and will remove the plastic when the moth is out.
Can’t help but wonder how far that bag with its dormant passenger was blown through the air before landing at Mayslake, a preview of the moth’s flying days to come.
The end of winter brings with it the prairie and savanna controlled burn season. Mayslake Forest Preserve got some of that attention, but it was more limited than the almost complete coverage of two years ago.
Only half of the north stream corridor prairie was burned, for instance.
A thread of fire reached into the edge of the stream corridor woodland and ignited the tall stump which I regarded as the most likely nest site for the great horned owls last year. It continued to smolder for days.
Several feet of one side burned away, showing that the cavity had been wide open and quite deep.
I don’t know if any owl eggshell fragments could be found in the former base of the cavity, but it’s a moot point now as they won’t be able to use this platform again.
It’s a moot point personally, too, as I will be retired next year and plan to shift my preserve monitoring to St. James Farm, a preserve closer to home.
In my idiosyncratic 6-season calendar, Late Winter begins March 1, and ends on the day that I see the first native wildflower blooming away from the warming influence of buildings. Last week that criterion was met when I saw a spring beauty flowering in Parson’s Grove at Danada Forest Preserve. This was a little earlier than usual, but we’ve had plenty of warm weather to date, so that is to be expected.
Spring beauty, though not this year’s first. Didn’t have a camera on me.
Yesterday many spring beauties were in bloom at St. James Farm as well.
Our bush katydids, genus Scudderia, have some of the most interesting song variations of all our singing insects. They include two “counting” species, with increasing numbers of syllables over a sequence of songs. Often they have more than one song type, and this is true of today’s featured species, the Texas bush katydid S. texensis (back in the days of the Bush presidency I was fond of pointing out that there really was a Texas bush katydid).
Texas bush katydid
The following recording includes two of the 3 song types: single clicks, which I seldom have encountered in the Chicago region, and the characteristic dusk or nighttime song, a series of quick buzzes.
During the day this species produces a very fast, 3-syllable call which I render “dig-a-dig.” It is similar to the daytime song of the broad-winged bush katydid, but the latter has more syllables (sounds like 5, usually) and they are less distinct because they have a lisping quality.
This week’s literature focus is on a single paper, which looked at a significant aspect of periodical cicada biology.
The northern periodical cicada species, Linnaeus’s 17-year cicada on the left, Cassin’s 17-year cicada on the right
Karban, Richard. 2014. Transient habitats limit development time for periodical cicadas.Ecology 95:3-8. He studied septendecim and cassini (our two local species of Magicicada) in New York state. There are several hypotheses explaining why their development times are so long: Pleistocene historical influences (long life span buffered annual climate variation in glacial refuges), predator satiation (some early maturing individuals wait for slower ones to catch up, and long life spans facilitate this), low nutrition forces long development, and increased fecundity (17-year species have been shown to be more fecund than the more southern 13-year versions). Here he examined the possibility that habitat quality changes rapidly enough to put an upper limit on such advantages of long lifespans. Though past studies pointed to possible advantages of edge trees, here he compared weights of newly eclosed adults from edge vs. forest interiors, finding the former to be only slightly (4.9%) heavier in septendecim but no difference in cassini. He took density of emerging nymphs as an indication of habitat quality. Changes in study sites were significant between emergences, enough to limit any advantage of longer life. He commented on the Raccoon Grove study site in Will County, once one of the highest-density populations known, mentioning that they plummeted over just a couple sequential emergences, first because of Dutch elm disease killing host trees. Karban and Yang visited that site in 2007, hearing one chorus but finding no emergence holes or nymphal skins.