Fiery Fall Foliage
First Week in November
The Chicago area landscape was formed by ice. As the Wisconsin glacier receded about 13,000 years ago, it deposited glacial till it had collected when it moved forward—boulders, stones, gravel, sand, and clay particles—and built overlapping moraines. The material dropped out unevenly thereby creating rolling hills, ridges, and kames. Where huge blocks of ice broke off from the glacier and melted, kettleholes were formed that became marshes, ponds, and lakes. (Jerry Sullivan, Chicago Wilderness, An Atlas of Biodiversity)
Burnidge Forest Preserve on the western border of the town where I live is one such area. An oak savanna that contains five species of oak–Bur Oak, White Oak, Black Oak, Red Oak, and Scarlet Oak–plus Shagbark Hickory grows throughout the rolling sandy hills, which slope down to three kettleholes.
The leaves of Bur Oak and Black Oak turn from green to crispy brown, but the White Oak, Red Oak, and Scarlet Oak turn to rich carmine and scarlet.
Entrance to Burnidge Forest Preserve–pond on the right.
A few magnificent Bur Oak and Shagbark Hickory followed the trail up the first hill. Smooth Sumac flamed along the edges. As I descended the slope on the other side of the hill, Scarlet, Red, and Black Oak came into view.
I crossed a road and then climbed another, steeper mound. Similar oaks covered the hill, mostly smaller White Oak, glorious in vivid carmine dress.
Continuing to the top of the hill, I overlooked another kettlehole, larger than the first two. Stands of Indian Grass and Little Blue Stem grew abundantly along with Showy Goldenrod in this open, sunny area.
Turning to the left, I followed another path down a slope mostly populated by White Oak. Both White Oak and Bur Oak are massive, wide-spreading, majestic trees at maturity. Bur Oak is common in savannas and woodland edges. While White Oak is still common in woodlands, Dick Young says in Kane County Wild Plants and Natural Areas that is only reproducing in a few locations. One such place is Burnidge Forest Preserve where we are now.
Broader than tall when mature, White Oak has a symmetrical, oblong, somewhat pyramidal crown when young, that concentrates its scarlet leaves like a flame. The leaves are round-lobed with deep sinuses almost to the rib. They tend to persist on the tree over winter, particularly on its lower half. A quick identification of White Oak is its ashy gray bark. I have noticed that In the wild it is most often found on hillsides, suggesting that it likes to grow in dry or dry-mesic situations.
Impossible to transplant beyond the seedling stage, it grows readily from acorns. When Jens Jensen designed the Lincoln Memorial Garden in Springfield, IL, school children were called upon to collect acorns, which were then planted by local Boy Scouts and Girl Scouts in a grand ceremony in 1936.
“I planted white acorns… The white oak is the noblest tree in Illinois. It will live to be a thousand years old on soil best fitted for it.”
as quoted by Robert E. Grese in his book, Jens Jensen.
Although the leaf color of Red Oak (Quercus rubra) is equally intense, the tree itself has a completely different look. Its branch structure is looser and sometimes asymmetrical. Its pointed-lobed leaves unfold reddish in spring, become shiny dark green in summer, turn to scarlet in fall, and finally change to russet brown and persist for most of the winter. Easy to transplant, it grows fast at a rate of 2’ per year to an ultimate height of 60’ to 75’ with a spead of 40-50’. Shade tolerant, it will grow with only a few hours of sun per day.
Turning around, I followed the path in the other direction. Scarlet or Hill’s Oak flourished to the left of the path. Scarlet Oak (Quercus coccinea) and Hill’s Oak (Quercus ellipsoidalis) were considered to be two different species until the last 15 or so years, but now are thought to be one and the same. Scarlet Oak was introduced in 1691, while Hill’s Oak, also known as Northern Pin Oak, was not discovered until the 1920’s by E. J. Hill. Scarlet Oak appears to be a tree of the East, while Hill’s Oak is common in the upper Midwest.
It closely resembles Pin Oak (Quercus palustris). Pin Oak, however, requires an acid, moist soil that is not found in the Midwest. But Hill’s/Scarlet Oak is an upland tree that grows well in dry, sandy, gravelly, or rocky soils. Unfortunately, it’s not readily available in commerce.
One more thing:
Do you know what this is? No, it’s not the alien Burning Bush, which has become invasive in our Forest Preserves. It’s Black Haw (Viburnum prunifolium), a lovely native small tree or large shrub that grows 15’ high and 8-12’ wide. It has interest in all 4 seasons: white blossoms in spring, rose berries, turning to black in September, and gorgeous scarlet to burgundy foliage in the fall, rivaling any Burning Bush. Its horizontal branching pattern is notable in winter and gives it the look of a hawthorn: hence the common name. And as a bonus, it reproduces itself by underground stoloniferous rhizomes and becomes a thicket. Or one can transplant the new plants to other places in ones own garden or dig to share with others. In nature, it is found in moist woods, or conversely in upland savannas and woodland edges; in the home landscape, it adapts to full or part sun. Plant it in the border or within a woodland, or use it as a specimen or focal point. It’s readily available from nurseries.
My Black Haw.