Where There’s Smoke

by Carl Strang

Mid-November brought forest preserve district crews to St. James Farm to conduct controlled burns in the forest. These burns are a normal part of oak woodland ecology in northeastern Illinois, and they help control invasive plants. Occasionally the consequences of the burn extend beyond the brief time when the flames consume the dry leaf litter on the ground, and I noted two such incidents this time around.

Carpenter ants commonly hollow out the base of a tree as they tunnel through the dead wood at the core. If the accumulated sawdust catches a spark from the controlled burn, a slow growing smoldering coal can expand to the point where it consumes a significant amount of the remaining wood.

A victim of that phenomenon was the large white oak that harbored the great horned owl nest last winter.

A victim of that phenomenon was the large white oak that harbored the great horned owl nest last winter.

There had been a larger live stem, and a smaller dead stem (the fractured one in the photo) where the nest had been. The live stem’s base was thinned by the growing coal to the point where it went down, taking the nest stem with it.

The same burn had the remarkable effect of catching in another tree, already knocked down by a storm, which then smoldered for weeks.

Here is the tree 2.5 weeks after the burn, on December 5. The underside of the fallen stem was burning slowly from west to east, and the top of the stem protected the coal from the snowfall.

Here is the tree 2.5 weeks after the burn, on December 5. The underside of the fallen stem was burning slowly from west to east, and the top of the stem protected the coal from the snowfall.

Another heavier snowfall still did not stop the burn, here on December 12. This was a cold day, but a moderate west wind kept the coal alive.

Another heavier snowfall still did not stop the burn, here on December 12. This was a cold day, but a moderate west wind kept the coal alive.

At that point, however, the coal was no longer sheltered. When I returned on the 16th, I found the fire had gone out. It had lasted nearly a month.

 

Exploring the Interior

by Carl Strang

Now that the leaves are down from the trees and shrubs, I have been exploring the areas between the forest trails at St. James Farm Forest Preserve. Those areas are large enough that I cannot cover the forest adequately from the trails. I have found deer runs and old equestrian paths that will provide sufficient access for routine monitoring. Along the way I have found some interesting places. One foggy day I zig-zagged my way through part of the western forest.

This area has been cleared of invasive honeysuckles and other shrubs. Part of it is young second growth with a few clearings where perennial herbaceous plants are growing.

This area has been cleared of invasive honeysuckles and other shrubs. Part of it is young second growth with a few clearings where perennial herbaceous plants are growing.

Elsewhere there are old trees, many of them red oaks.

Elsewhere there are old trees, many of them red oaks.

Among the occasional boulders was this outwash-rounded fossiliferous one.

Among the occasional boulders was this outwash-rounded fossiliferous one.

The chunk of local Silurian dolomite appears to have been a spot on the ocean floor, adjacent to a reef, where there was a crinoid colony.

The chunk of local Silurian dolomite appears to have been a spot on the ocean floor, adjacent to a reef, where there was a crinoid colony.

A morainal depression held a huge fallen red oak.

A morainal depression held a huge fallen red oak.

The tree had lost the grip of most of its roots in the soil.

The last roots that were holding the tree up still show the relatively fresh color where they fractured.

The last roots that were holding the tree up still show the relatively fresh color where they fractured.

The orientation of the trunk relative to those broken roots suggests that a very strong wind from the west was the culprit.

 The oak didn’t go down alone. Broken stems reveal the trees it took out on either side. The force of the fall split the oak’s stem lengthwise.

The oak didn’t go down alone. Broken stems reveal the trees it took out on either side. The force of the fall split the oak’s stem lengthwise.

Each day in this exploration has brought its own delights.

Here, a beautiful moss colony became established on an old burn scar.

Here, a beautiful moss colony became established on an old burn scar.

One day when I was the preserve’s only human visitor, I saw one of St. James Farm’s coyotes. The fat belly and good coat indicate that this animal is a successful hunter.

One day when I was the preserve’s only human visitor, I saw one of St. James Farm’s coyotes. The fat belly and good coat indicate that this animal is a successful hunter.

So now the stage is set for routine coverage of St. James Farm’s ongoing natural history story.

 

First Snow

by Carl Strang

Our first winter storm of the season was worthy of the name, with 24 hours of occasionally heavy snowfall and strong winds. Even after some of the first snow melted in contact with the ground, St. James Farm Forest Preserve ended up with 3-6 inches on the ground. On Sunday I took an extended walk through the northern, forested portion of the preserve.

I wasn’t alone. Many hikers, skiers and snowshoers took advantage of the fresh snow.

I wasn’t alone. Many hikers, skiers and snowshoers took advantage of the fresh snow.

The wet snow stuck to the vegetation.

The wet snow stuck to the vegetation.

Herbaceous plants bowed under the weight.

Herbaceous plants bowed under the weight.

The smaller birds were challenged to find food through this obstruction. The temperature was cold enough to freeze shallow ponds.

This pond is hidden in the northwest corner of the woods.

This pond is hidden in the northwest corner of the woods.

This was my first opportunity to get an overview of mammal activity across the preserve. The absence of cottontail tracks perhaps was the biggest surprise. The more open southern part of the preserve, which I did not check, is more suited to them.

I saw only one set of opossum tracks, but would not expect much activity from them under the conditions.

I saw only one set of opossum tracks, but would not expect much activity from them under the conditions.

White-footed mice are abundant in the forest.

White-footed mice are abundant in the forest.

Coyote tracks showed a thorough coverage of the area overnight.

This footprint was made soon after the main snowfall ended. Ice crystals formed within it afterward.

This footprint was made soon after the main snowfall ended. Ice crystals formed within it afterward.

A pair of coyotes hunted together for a time.

A pair of coyotes hunted together for a time.

Though the disruption of the rut makes any pattern temporary, I was interested in assessing deer activity as well.

A few individuals crossed Winfield Road between St. James Farm and Blackwell Forest Preserves.

A few individuals crossed Winfield Road between St. James Farm and Blackwell Forest Preserves.

Half a dozen deer moved together at one point. The main activity was in the western portion of the woods, with almost all movement trending east-west. Only a couple deer, moving north-south, left tracks in the eastern portion. All of this is subject to change when things settle into the winter pattern over the next month.

 

July Flowering Phenology

by Carl Strang

July was the last month in which I collected phenology data from Mayslake Forest Preserve. The results provided a satisfactory conclusion.

Many of Mayslake’s prairie plants first open their flowers in July.

Many of Mayslake’s prairie plants first open their flowers in July.

First flower dates become less different among years as the summer progresses, and that was true this year as well. The median difference from 2014 was 0 days for 47 species, an insignificant 2 days earlier than in 2013 for 31 species and the same vs. 2011 for 37 species, 1 day later than in 2010 for 37 species, and a slightly larger 5 days earlier for 35 species in comparison to 2009. The odd early year of 2012 continued to be the outlier, but even that difference was down to 10.5 days for 38 species.

Michigan lily provides one of the preserve’s more extravagant floral displays.

Michigan lily provides one of the preserve’s more extravagant floral displays.

All those medians were smaller than those for June, except the one for 2013, which was the same.

 

Pocket Prairie

by Carl Strang

This is the time of year when the view out my back window is best.

The diversity of blooming wildflowers hits its peak in late July.

The diversity of blooming wildflowers hits its peak in late July.

My neighborhood for the most part is a wildlife desert. It’s amazing what a little habitat can bring, though. These native prairie flowers attract diverse pollinators, and bumble bees for instance always are present in the daylight hours. The red blooms are royal catchflies, which never fail to bring hummingbird visitors in July and August. Later, goldfinches will be after the seeds in the purple coneflower heads. My original planting plan is history, as most of these plants are seeding into the tiny spaces left between. My main work has shifted from planting to thinning, keeping the better competitors at bay so as to maintain a balance of biodiversity. That makes me a member of this community, too.

June Flowering Phenology

by Carl Strang

First flower dates at Mayslake Forest Preserve in June continued the trend of convergence on earlier years that is typical of the progressing season. The median difference from 2014 for 71 species was only one day earlier, and two days earlier than 2013 for 69 plant species.

Butterfly weed was among the species that first opened flowers in June.

Butterfly weed was among the species that first opened flowers in June.

The biggest difference continues to be with the very early year of 2012, but that is down to a median of 11 days later for 71 species. The difference for the remaining three years is not large: 5 days earlier than 2011 for 61 species, 5 days later than 2010 for 49 species, and 6 days earlier than 2009 for 51 species.

Compass plants began to bloom just before the end of June.

Compass plants began to bloom just before the end of June.

These differences represented reductions of 6 days, 3 days, 7 days, 1 day, and 4 days from May values for the years 2014-2010. The difference for 2009 increased by 3 days.

May 2015 Phenology

by Carl Strang

April’s phenological signal held true in May’s first flowering dates. This year continues to run ahead of most, but not by much.

Ohio buckeye was among the plants that bloomed in May.

Ohio buckeye was among the plants that bloomed in May.

Median first flower dates this May at Mayslake Forest Preserve were 7 days earlier than last year (54 species), 5 days earlier than in 2013 (70 species), 18 days later than in 2012 (69 species), 4 days earlier than in 2011 (68 species), 7 days later than in 2010 (45 species), and 3 days earlier than in 2009 (46 species).

Common spiderwort is peaking now, but started blooming in May.

Common spiderwort is peaking now, but started blooming in May.

The respective numbers for April were, in the same order: 6 days earlier, 9 days earlier, 25 days later, 6 days earlier, 9 days later, and 3 days earlier. On the whole this shows the usual trend of convergence among years as the season progresses.

A number of sedges first bloomed in May, including the small yellow fox sedge.

A number of sedges first bloomed in May, including the small yellow fox sedge.

Phenology First Take

by Carl Strang

One of the best ways of assessing how a given year compares with previous ones is by looking at first flowering dates. With April now complete, I can review those for Mayslake Forest Preserve. On the whole, this April can be regarded as slightly early, thanks to significant early warm days melting the snow and warming the soil.

Dutchman’s breeches bloomed abundantly at Mayslake this year.

Dutchman’s breeches bloomed abundantly at Mayslake this year.

Comparing median first flower dates in April places 2015 6 days earlier than 2014 (11 species), 9 days earlier than 2013 (20 species), 6 days earlier than 2011 (21 species), and 3 days earlier than 2009 (17 species). This April was 9 days later than 2010, and a substantial 25 days later than the anomalous warm year of 2012.

Most of these differences are not very large, and the expectation is that they will gradually diminish over the coming months.

Spring Progresses

by Carl Strang

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 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.

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 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.

Literature Review: Pleistocene and Holocene

by Carl Strang

Today’s notes are from last year’s literature on the recent ice ages and subsequent prehistoric times. Some are biological in focus, others relevant to past and present climate change.

Coyotes once were bigger and more carnivorous than they are today, according to the following study.

Coyotes once were bigger and more carnivorous than they are today, according to the following study.

Meachen, J.A., A.C. Janowicz, J.E. Avery, and R.W. Sadleir. 2014. Ecological changes in coyotes (Canis latrans) in response to the ice age megafaunal extinctions. PLoS ONE 9(12): e116041. doi:10.1371/journal.pone.0116041 They measured coyote skulls from 29,000 years ago (La Brea tar pits) to present day, and found a transition from features associated with predation specialization to the present-day omnivory. Another study had found in addition a decrease in body size. They interpret this as a change in predator interactions. When the much larger dire wolf was the other dominant canid, and megafauna were abundant, coyotes could make a good living as specialist predators. Megafauna loss, and associated dire wolf extinction, opened the door for gray wolf immigration from Europe. This new, smaller predator was similar ecologically, but at the same time larger than the coyote, forcing a coyote niche shift to a more generalized diet.

Maher, K., and C.P. Chamberlain. 2014. Hydrologic regulation of chemical weathering and the geologic carbon cycle. Science 343:1502-1504. Kerr, Richard A. 2014. How Earth can cool without plunging into a deep freeze. Science 343:1189. The Kerr news article was based on the Maher and Chamberlain paper. The study looked at the mechanism that limits ice age cooling, preventing it from running away to a pole-to-pole glaciation. Volcanoes add carbon dioxide to the atmosphere, warming climate but also dissolving in rainwater, the resultant carbonic acid dissolving rock. The products flow to the sea, are taken up by plankton for skeleton building, and ultimately are buried. This removal process limits carbon dioxide buildup. Most of the dissolved rock is in mountains, and mountain uplift as in the Andes and Himalayas thus is tied to a global thermostat turndown. However, cooling slows the weathering reactions, allowing carbon dioxide to build back up.

Pena, Leopoldo D., and Steven L. Goldstein. 2014. Thermohaline circulation crisis and impacts during the mid-Pleistocene transition. Science 345:318-322. They found evidence for a profound change in oceanic circulation patterns corresponding to the change in glacial cycling from 41-thousand-year to 100-thousand-year durations. They conclude that “North Atlantic ice sheets reached a milestone in size and/or stability” that led to the ocean circulation change, resulting in a greater carbon dioxide drawdown, increased polar glaciation, and setting the pattern for the following 100,00-year cycles.

Guil-Guerrero, J.L., et al. 2014. The fat from frozen mammals reveals sources of essential fatty acids suitable for Paleolithic and Neolithic humans. PLoS ONE 9(1): e84480. doi:10.1371/journal.pone.0084480 They analyzed the fat chemistry of frozen woolly mammoths, horses and bison from Siberia. The fats were judged to be nutritionally good for human hunters of the time (41,000-4400 years ago). Furthermore, the fats of mammoths and horses were like those of hibernating mammals. The authors suggest that the mammoths and horses hibernated in similar fashion to present-day Yakutsk horses, which move little and mainly stand in sleeping positions during the coldest weather. The mammoth fatty acids suggest derivation from certain lichens in the diet.

Willerslev, Eske, et al. 2014. Fifty thousand years of Arctic vegetation and megafaunal diet. Nature 506 (7486): 47. DOI: 10.1038/nature12921 A large, multi-national team went into Pleistocene sediments and mummified gut contents, and used reference DNA from herbarium specimens to characterize vegetational changes over the past 50,000 years. They found that the last ice age caused a significant alteration of northern plant communities, greatly reducing forbs while increasing grasses and woody plants. Many of the megafauna herbivores such as woolly rhinoceros and woolly mammoth depended on the forbs for their protein content, and the authors believe that the failure of forb-rich communities to re-form after the ice receded contributed to or even caused megafaunal extinctions. No mention was made of human hunting in the ScienceDaily article describing the study.

Hoffecker, J. F., S. A. Elias, and D. H. O’Rourke. 2014. Out of Beringia? Science 343 (6174): 979. DOI: 10.1126/science.1250768 They reviewed cores taken from the Bering Sea and found that Beringia was not a barren grassland through the glacial times but had significant areas of tundra shrubs and trees. Animals including elk and moose likely lived there, and the likelihood of long-term human occupation seems good. This could provide a way that the ancestors of Native Americans could have been isolated from Asians for the 10,000 years, between 25,000 and 15,000 years ago, accounting for the genetic differences comparisons show. Beringia was not glaciated, and summers may well have been like those of today, though winters would have been severe. When the glaciers opened a way by melting, the 15,000-year Native American presence in the continent began as the Beringians moved in.

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