November 24, 2009 at 6:51 am (botany, ecology, restoration)
Tags: Euonymus obovatus, trailing strawberry bush, Meacham Grove, Maple Grove, controlled burn
by Carl Strang
Recently I described this year’s results in my ongoing study of the trailing strawberry bush, Euonymus obovatus, at Meacham Grove Forest Preserve. There was notable growth in the median size of patches or colonies of the plant in 2009, which may have benefited from a controlled burn that took place there in 2007.
The graph shows that Euonymus patch size dropped in 2008, apparently from burn damage. The jump in 2009 I suspect was the result of the fire’s harming Euonymus competitors and giving the trailing strawberry bush an opening. Trailing strawberry bush colonies approached sizes they had not achieved since the 1980’s. I returned to Meacham Grove, as well as Maple Grove, on November 11 to collect data on leaf miners in maple trees. I found that both study areas had received controlled burns.
At least some of the Euonymus twigs were severely scorched.
Burned stems like the one in the photo represent a setback for the species, but the previous burn helped by reducing the competition. Now I am interested in seeing how this trailing shrub will respond over the coming season.
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November 10, 2009 at 6:51 am (ecology)
Tags: Cooper's hawk, coyote, ecology, great horned owl, Mayslake, mink, red-tailed hawk, trophic structure, white-tailed deer
by Carl Strang
I’ll conclude the summary of my first year at Mayslake Forest Preserve with an ecological sketch. The preserve has diverse plant communities, some high in quality thanks to the restoration efforts I described yesterday. There are lakes, a stream, savannas, prairies, a couple small marshes, European meadows undergoing succession, a degraded former garden at the friary and brushland areas dominated by Eurasian species of shrubs, as well as lawn areas around the mansion and friary grounds.
This habitat variety leads to the diversity of plants and animals I mentioned a couple posts ago. Strongly reproducing populations of cottontails, squirrels and other small mammals, as well as various small birds, support a suite of predators somewhat surprising for such a small preserve: a pair of great horned owls, a pair of coyotes, a couple mink, Cooper’s hawks and, in winter, red-tails.
Of course, these predators do not limit their activities to the preserve’s borders. White-tailed deer pass through the preserve regularly, but Mayslake is not quite large enough at 90 acres to hold many or to be more than an occasional center of activity.
This summary of course hides a lot of detail, some of which I observed and reported here over the past year. I will continue to do so as the details and patterns of that place change over time, keeping it refreshingly interesting.
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October 22, 2009 at 7:15 am (birds, botany, ecology)
Tags: Aesculus glabra, cedar waxwing, common buckthorn, European highbush cranberry, false Solomon's seal, food mimicry, mastodon, mutualism, Ohio buckeye, Rhamnus cathartica, robin, seed dispersal, Smilacina racemosa, Solomon's plume, Viburnum opulus
by Carl Strang
Earlier I featured several plants at Mayslake Forest Preserve that produce fruits timed to coincide with the fall migration of berry-eating birds. This mutualistic interaction for the most part benefits the birds, through nutritional provisioning, while the plants get their seeds dispersed. Today I want to feature some outliers to this pattern. Let’s start with Solomon’s plume, also known as false Solomon’s seal.
Like many fall fruits, these advertise themselves to birds with a bright red color. When analyzed, however, the berries proved to be junk food, or perhaps are more accurately described as food mimics (White and Stiles 1985, Ecology 66:303-307). The plants save their energy, investing no nutritional value in these fruits. The ruse works, apparently, by exploiting the naïve instinctive response of first-time autumn migrants, the young of the year. A little different from this is the offering of the European highbush cranberry.
Another study (Witmer 2001, Ecology 82:3120-3130) showed that the nutritional value of these berries becomes available only when they are consumed along with a significant protein source. I was impressed to learn that, like the waxwings native to the shrub’s European home, our North American cedar waxwings ignore these tempting berries until spring, when cottonwoods or other poplars are flowering. Then the birds consume the berries along with cottonwood catkins, protein in the pollen providing access to the berries’ nutritional value.
These black berries are common buckthorn fruits. They generally are ignored by birds until late winter when, apparently, the better quality foods have been depleted. Then, robins and waxwings consume them, unfortunately dispersing the seeds throughout our woodlands. Buckthorns leaf out early and lose their leaves late, casting a shade so dense that no other plants can grow beneath them. This is why these Eurasian shrubs must be removed at the beginning of woodland restoration projects. A final fruit is of no interest to birds.
Ohio buckeyes in fact are largely ignored by animals generally. This opens the possibility that, like other trees I discussed earlier, buckeyes may have been dispersed by now-extinct mastodons and other large herbivores.
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October 13, 2009 at 5:50 am (botany, ecology, history (human), methods)
Tags: Acer saccharum, beech, Carya, Culver, Culver Military Academy, dry forest, Fagus grandifolia, fish hatchery, hickory, Larix laricina, Marshall County Indiana, Maxinkuckee Moraine, mesic forest, Moore Lake, oak, original land survey, Quercus, savanna, soils map, sugar maple, swamp, tamarack, The Nature Conservancy, Union Township
by Carl Strang
Yesterday I began to recount my study of what my home township in Indiana was like in the 1830’s, before Americans began to transform it from wilderness to a predominantly agricultural landscape. Here is a more detailed line drawing of the final map.
The surveyors’ description provided enough information for me to rough out the map. Getting to the final version required another step. I acquired a soils map of Marshall County, and looked for correlations between soil types and vegetation categories as the surveyors described them. A specialist might have done it differently, but for my part I was satisfied that the correlations were good enough to draw the detailed boundaries of vegetation areas by combining the surveyors’ records with the finer-scale soils map.
Of the various communities defined by woody plants, swamps are the ones most absent from today’s Union Township. The characteristic swamp tree was the tamarack. Here is some foliage of that species, which is unusual in that it is a deciduous conifer.
I remember seeing a tamarack tree at the old state fish hatchery that was formed out of the south end of Moore Lake, but that tree died years ago and I know of none surviving in the township today. There are bits of shrub swamps here and there.
A relatively moist (mesic) forest occupied much of the east half of the township, on the rolling Maxinkuckee Moraine. Sugar maples and beeches were characteristic trees, though not necessarily the dominant ones. A remnant of this forest is preserved by the Culver Military Academy in its Bird Sanctuary.
Dry forests and savannas were dominated by oaks and hickories, which grew on more sandy soils. They represent a continuum, with the forests shading the ground fully in the summer and the savannas’ trees scattered enough that prairie-like vegetation grew between them. A forest of this type was the site of the town now known as Culver. Gradually over my lifetime I have noted the passing, one by one, of the town’s largest surviving old oaks that were part of that forest. Dry forests persist mainly in the many “wood lots” preserved by the township’s farmers.
I am grateful to all the individuals and organizations, from private landowners to The Nature Conservancy, who have made the commitment to preserve and restore these reminders of the wilderness that once was.
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October 12, 2009 at 6:24 am (botany, ecology, history (human), methods, restoration)
Tags: Culver, Houghton Lake, Lake Maxinkuckee, Lost Lake, marsh, Marshall County Indiana, Moore Lake, pitcher plant, prairie, presettlement vegetation map, sedge meadow, sundew
by Carl Strang
The places we live and work all were wilderness at one time. National parks, state parks, and nature preserves protect and restore areas intended to represent the landscape as it was before large scale agriculture began the sequence of alterations that have brought us to the present day. A number of studies have produced maps showing, in some detail, what the counties of northeast Illinois looked like 200 years ago. In the late 1980’s I decided to do the same for my home area, Union Township in Marshall County, Indiana. Here is a watercolor rendering of my results.
I was reminded of that project by Scott’s excellent recent post on Houghton Lake in his blog, Through Handlens and Binoculars. Houghton Lake is the small lake closest to the map’s upper left corner. Recently it was acquired by The Nature Conservancy, and is getting the attention needed to preserve the rare plants and vegetation communities that have persisted there.
My mapping study began with a visit to the County Surveyor’s office in Plymouth, the county seat, to copy the original survey notes. Two different surveyors explored the local wilderness in 1834 and 1836, marking out the land on behalf of the federal government for purchase by American farmers. The 1836 survey covered the Indian reservations east of Lake Maxinkuckee, the township’s largest lake. That land became available to eastern farmers after the forced removal of the Potawatomis via the Trail of Death in 1838.
The surveyors’ main job was to mark the section corners and quarter-section corners (a section is a square mile). They also described the land, so that potential buyers back east could make informed choices. For example, after passing through what is now the center of the town of Culver, on Maxinkuckee’s west shore, surveyor David Hillis wrote, “Land rolling. 3d rate. Hickory etc.” Usually the description was dispassionate, but sometimes a surveyor revealed the sweat and discomfort of the experience. After crossing an extensive marsh at the south end of Maxinkuckee, Jeremiah Smith allowed, “In Sec. 34, at 1.20 (an) inlet 80L. wide coming from S.E. A nasty place.”
One of the surveyor’s helpers blazed and inscribed two “witness trees” at each section corner. The surveyor wrote down the species of tree along with its distance and direction from the corner. The tree species suggests to us what kind of vegetation community occupied that corner, and the tree’s distance from the corner hints at how close together the trees grew in that spot.
The surveyors also were careful to map the edges of lakes and rivers. In Union Township only Lake Maxinkuckee and Lost Lake, off its west edge, still have their 1834 outlines. Houghton Lake, and Moore Lake beside it, today are remnants of the larger water bodies they were in the early 1800’s. Two other lakes in the west-central part of the township no longer exist. They were shallow and easily drained for agricultural purposes before 1900.
Plant communities described by the surveyors as “wet prairies” or “marshes” were extensive mixtures of cattail marshes, sedge meadows and wet to moist prairies. Some of these featured insect-eating plants, the pitcher plants and sundews. See Scott’s post for photographs of some of the botanical beauty preserved around Houghton Lake. I’ll continue this account tomorrow.
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October 7, 2009 at 5:45 am (botany, ecology, plant-eating insects)
Tags: ermine moth, Euonymus obovatus, Meacham Grove, trailing strawberry bush, Yponomeuta multipunctella
by Carl Strang
A continuing study that I began in the 1980’s regards a low forest shrub, the trailing strawberry bush (Euonymus obovatus), at Meacham Grove Forest Preserve. Last year I outlined the history of this study. The plant’s nemesis, colonial web-spinning caterpillars of a tiny ermine moth, have been absent from the scene since 2002, and did not return in 2009. The photo below shows a caterpillar-free sprig this past June.
September is when I make my annual check of Euonymus patches at Meacham. Leaf consumption by herbivores was minimal in 2009, less than 10% in 14 of 16 surviving patches. The other two patches lost around 10%. Though the plants were affected by a controlled burn in 2007, the net effect for them appears to have been positive as competitors were hurt more than were Euonymus. Of the 16 patches, 14 showed growth in 2009, one was the same size as last year, and one was smaller. The median product of patch length x width is 5.5 m2, an increase from last year’s value of 1 m2. Since these patches are rather sprawling, containing a lot of empty space, a better measure is the rough coverage if the scattered elements of the patch all were brought together. In 2009 the range was 0.01 – 2 m2, median 0.25 m2. Even 2 m2 apparently did not provide enough photosynthetic power for fruit production. I have not seen fruit at Meacham since 2002.
However, if growth continues I expect to find the beautiful fruits of these plants returning in the next few years.
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October 5, 2009 at 5:53 am (botany, ecology, mammals)
Tags: periodical cicada, Mayslake, gray squirrel, fox squirrel, bur oak, Quercus macrocarpa, mast, mast year, acorn, white oak, Quercus alba, black walnut, Juglans nigra, hickory, Carya, coevolution
by Carl Strang
Mast is a collective term referring to nuts and acorns. Trees do not produce these in the same amounts each year. In some years very few nuts or acorns develop in a given species, and in other years prodigious numbers appear. High production seasons are called mast years. 2009 is proving to be a mast year for bur oaks and white oaks at Mayslake Forest Preserve, where the trails in places are littered with the fallen acorns. Here is an example for bur oak.
Here, white oak acorns abound.
Though elsewhere I am seeing lots of walnuts, this does not seem true for that species at Mayslake, which also is having an unremarkable year for hickory nuts. Nearby, at Fullersburg Woods Forest Preserve, I noted in 2007 that walnuts, hickories and red oaks had a mast year. It is common for members of the white oak group and red oak group of species to be decoupled from one another in their mast years.
As you might imagine, animals such as tree squirrels are impacted by mast years. Mayslake’s gray and fox squirrels will have an easy winter with so much food available. They help their cause by biting acorns before burying them in an effort to kill them. The acorns, in a countermeasure, are quick to sprout when they fall to the ground. A study published in 2006 in Science (314:1928) found that red squirrels (which live north and south of us, but not in DuPage County) themselves reproduce more heavily in mast years (perhaps responding to an increase in flowering or other advance cue). Such adaptive interactions between species are referred to as coevolution. The phenomenon of the mast year itself likely is, at least in part, an evolutionary tactic by the trees. By coordinating their mast production they can limit their seed-predators’ survival in some years, overwhelm them in others. Such an episodic mass reproduction is reminiscent of the periodical cicadas.
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July 29, 2009 at 6:10 am (birds, botany, ecology, gardening, insects (other), plant-eating insects)
Tags: Asclepias tuberosa, Bombus bimaculatus, Bombus griseocollis, butterfly weed, Danaus plexippus, garden, gardening, monarch, nectar thief, royal catchfly, ruby-throated hummingbird, Silene regia
by Carl Strang
Our yards are habitats for wildlife. We have no choice in that. We can, however, influence what kinds of wildlife will visit us or live with us on the land. This is true even for a tiny yard like mine. Here are some examples from my prairie flowerbeds, which are approaching their peak now.
I have planted royal catchflies all out of proportion to their presence in our local prairies.
As a result, I can count on regular visits from ruby-throated hummingbirds in July and August. Here is this year’s happy camper, photographed through the kitchen window.
I kind of like this impressionistic view of the same bird.
Red tubular flowers shout “hummingbird” to ecologists, and to the birds themselves. I wonder if royal catchfly flowers also have evolved the means to defeat nectar thieves.
This Bombus bimaculatus bumblebee behaved as though it were in one of those sticky-slow-motion nightmares. The hairs on the royal catchfly calyx either were affecting it chemically, or physically had grabbed it. It wasn’t struggling strongly, so I suspect the former. As far as I know, no bumblebee has a tongue long enough to reach the nectaries of this flower from the front. Bumblebees are known to pierce such flowers from the outside, getting nectar but bypassing the anthers, therefore not serving the plant’s need for cross pollination. Such nectar thievery could provide selective pressure favoring any adaptation in the plant that might prevent the would-be perps from being successful.
In any case, I have plenty of bimaculatus visiting my other flowers, and also a few Bombus griseocollis.
A final species for this time is the monarch.
This half-grown caterpillar is doing well on one of my butterfly weed plants.
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June 18, 2009 at 5:49 am (botany, ecology)
Tags: fruit, Lonicera tatarica, Mayslake, phenology, tartarian honeysuckle
by Carl Strang
Through the spring I have been introducing wildflowers as they have bloomed at Mayslake Forest Preserve. I record first flowering dates so as to make future comparisons between years. Flower timing is tied to climate. Plants, especially early in the season, are influenced strongly by soil temperature. Phenology, the study of when events occur, is by no means limited to flowers, or even to plants. I record arrival dates for birds, and also fruiting dates of plants whose fruits are consumed by vertebrates. This year the first of these at Mayslake has been a non-native species, the Tartarian honeysuckle.
The berries are consumed by birds, which disperse the seeds widely, enabling it to become a problem plant in restoration projects. I’ll share other fruits in future installments.
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June 9, 2009 at 10:56 am (archeology, botany, ecology)
Tags: curly dock, Frank Keller, friary, lichen, Mayslake, moss, primary succession, Rumex crispus, Senecio pauperculus, soil formation, Wayne Lampa
by Carl Strang
A few days ago I shared an account of a morning spent with botanist Wayne Lampa and restoration steward Frank Keller. As we searched for lichens on the north deck of the old friary, Wayne remarked at how its bricks were becoming obscured by the plant growth.
Mosses had become established in the spaces between the bricks, and had spread over the edges. Those mosses in turn had provided a substrate in which a number of vascular plants were growing.
The most spectacular of those that day were balsam ragworts.
Curly dock was another.
This sequence of events is close to the ecological process of primary succession, in which life becomes established in stages on a new substrate that did not have life on it before. Wayne’s and Frank’s study of lichens, particularly those on the concrete and rocks, was in part an examination of the first stage of primary succession. Whether the friary deck counts as primary succession I would have to leave for a plant ecologist to say. There was a little soil between the bricks to provide a foundation for the mosses. Given time, the deck could be covered by a deeper and deeper layer of soil, ultimately with a forest growing over it, reminiscent of lost Mayan ruins in the jungles of Central America.
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