Stewardship Begins

by Carl Strang

Earlier this spring I began my work as volunteer steward of McCormick Woods, the main forest at St. James Farm Forest Preserve. The stewards provide backup and extension of the ecosystem restoration work by Forest Preserve District staff. The McCormick Woods ecosystem is the highest quality forest in the western half of DuPage County, and the District has put considerable effort into its restoration, but there still is plenty for volunteers to do. Invasive shrubs and herbaceous plants are established in significant portions of the forest, there supplanting the diverse native plant and animal community.

I have had the help of two other volunteers, Wayne and Bob, and we have made a good start. We began by focusing on garlic mustard, an invasive and allelopathic biennial, in two large areas where native plant diversity is excellent and garlic mustard is not yet well established. We took the bushels of pulled garlic mustard plants and dumped them in two locations, hoping to make progress against the forest’s biggest threat: goutweed.

Goutweed is a perennial member of the parsley family (Apiaceae, formerly Umbelliferae).

Goutweed was imported from its native Europe and commonly is planted as an ornamental ground cover. Apparently it was used in the landscape around the McCormick residence at St. James Farm. Unfortunately it spread into the adjacent forest, and significant colonies of the plant have supplanted the native forest flora in places. Repeated applications of herbicides by District staff may have slowed it down, but do not kill it. Stronger herbicides that would kill it also would threaten the trees.

I selected goutweed colonies in two locations as garlic mustard dump sites. I wanted to see if masses of pulled plants might smother the goutweed, hoping also that allelochemicals might leach out and inhibit goutweed growth. The goutweed has proven to be resilient.

Goutweed leaves pushed up through the piles of garlic mustard in the first location, which had not received an herbicide spray earlier in the spring.

The second dump was in goutweed that had been hit by herbicide. It is too soon to say whether the results are any better.

At some point I want to take measurements to see how fast the goutweed colonies are expanding, and whether these efforts slow that growth.

Now that the garlic mustard pulling is done for the year, we have shifted to another location and are cutting common buckthorn and Amur honeysuckle. That part of the forest still has a good diversity of native woodland plants hanging on beneath the invasive shrubs.

Here is part of the area we have cleared. Increased light levels should allow native plants to expand their populations.

We are creating a brush pile of the cuttings that later will be burned.

There are no goutweed patches in that part of the forest. Burning brush piles would kill the goutweed beneath them.

I was inspired to take on the stewardship job by the diversity of life in McCormick Woods. Some recent photos:

Shooting stars have popped up here and there where they were released by the removal of invasive brush.

Giant swallowtails appear occasionally at St. James Farm.

A recent addition to the preserve species list was this Zabulon skipper.

Insects at the Campground

by Carl Strang

The overnight campout at Waterfall Glen Forest Preserve that concludes the Roger Raccoon Club provides opportunities to observe various aspects of natural history. Last week the campground’s gravel parking lot, damp from overnight rain, apparently held a good supply of dissolved minerals, as it attracted butterflies representing at least 5 species.

Most remarkable was this giant swallowtail, a species uncommon in DuPage County but encountered regularly in small numbers at Waterfall Glen. I believe their main food plant in northeast Illinois is prickly ash, an infrequent shrub.

After dark an orchestra of singing insects filled the forest with sound. Dominant that night were large numbers of common true katydids, with smaller numbers of scattered two-spotted tree crickets, rattler round-winged katydids, and oblong-winged katydids. I needed a photo of the last species, and was able to find one singing close to the edge of the woods.

This oblong-winged katydid is holding his wings apart in singing position. Rasp and file structures on the brown portions of the two wings are rubbed together to produce the song.

As it happened, some of the kids found another male on their tent in the morning. I gave them a brief lesson about it, and took another set of photos.

Here the wings are in their normal folded position.

Some of those singing insects represented my first observations of their species this year.

%d bloggers like this: