Fall Project 2017

Each year during September and October, I tend to embark on a large scale management project at Blue Jay Barrens.  This year I worked to systematically eliminate all invasive shrubs from a 16 acre block that was historically used as a crop field in the early 1900’s.  Since all invasive shrubs of seed bearing age appear to have been eliminated from the property, I thought the next step should be to aggressively pursue the youngsters.  My primary problem shrubs are Multiflora Rose, Bush Honeysuckle, Japanese Barberry and Autumn Olive as shown in the lineup in the photo above.  I also find a few Privet and a couple of Winged Wahoo.

My project area sits on a long south facing slope and is a roughly rectangular shape measuring 900 by 800 feet.  The area is currently a patchwork mix of large Eastern Red Cedars, mixed hardwoods, and barrens openings.  I began work at the east property line and worked my way west in a series of strips paralleling the fence line. Each strip ran from the creek up to the hill top, an elevation difference of about 140 feet.  The neighboring property has a growing population of invasives and birds bring plenty of seeds across the property line.  Invasive shrubs were especially prevalent within 100 feet of the fence.

To make my search as thorough as possible, I produced a grid pattern by using marking flags to establish the strips and to show the corners of each cell within the strip.  Strips were about 20 feet wide and each cell was about 35 feet long.  This resulted in around 1,000 cells developed within the project area.  I began by establishing two strips using three lines of flags; one red, one blue, and one yellow.  As I completed each strip, I would move the line of flags west to make a new strip.  Within each cell I would walk a line about three feet in from the side, cross over at the end and walk about three feet in along the other side, and then travel up the center until I reached the next cell.  There’s no place within that 16 acres that I wasn’t within a few feet of while searching.  Every invasive shrub found was cut off at ground level and the resulting stump treated with glyphosate.  Most of the treated individuals were less than two feet tall.  If I could see it, I would treat it.

Of course, that doesn’t mean I found every invasive shrub there was to find.  Surrounding native vegetation often hid the invaders.  Dappled sunlight could also be effective camouflage.  Despite these obstacles, I drastically reduced the number of unwelcome shrubs.

Even shrubs that appear impossible to miss can be hidden from view.  This Bush Honeysuckle could not be seen from the other side of the tree.

The concentration of invasives was greatest beneath trees used by roosting or resting birds.  The photo above shows an Autumn Olive, a Bush Honeysuckle and a Multi-flora Rose, three of a larger collection of similar specimens all inhabiting the same small area of ground. 

The cause of the infestation was a large Sycamore, the trunk of which can be seen here in the background.  Flocks of Robins and Cedar Waxwings seem to spend considerable time in the upper branches of towering Sycamores, often after making a large meal of fruits from surrounding shrubs.  While resting, they are also dropping seeds into the fertile soil beneath the tree.

It’s common to find a clump of seedlings that has developed on the site of a seed filled bird dropping.  This jungle of Autumn Olive seedlings resulted from a single bird drop.  

The seedlings must now compete among themselves for survival.  The plants at the edge of the cluster stretch out to capture sunlight.

The clump may appear to be spread over a rather wide space, but clipping the tops reveals that all stems are originating from a single small spot.

Invasives were cut and treated in this area in a slightly less intensive search conducted four years ago.  These two Bush Honeysuckle stems and the stump from which they were cut are a result of that management effort.  I was concerned when I found many Bush Honeysuckle seedlings growing in a roughly 10 foot diameter circle centered around the dead stump.  Could seeds from fruit that fell uneaten to the ground germinate after several years of natural stratification?  If so, this could cause another complication in the battle to control these invasives.  Hopefully, this is just the result of some seed laden birds that just happened to roost above this old bush site.

Multiflora Rose growing on the dry, rocky slopes show an interesting growth pattern.  Most have been growing for many years as indicated by the thick stump found at ground level, but the plants display only the current year’s growth.  Dieback due to harsh conditions seems to be a perennial problem for these roses.  That doesn’t stop them from trying anew each year.  The plant shown above has one live stem produced this year, one dead stem produced last year, and numerous scars on the stump from previous years.

Multiflora Roses also have a habit of sending out a horizontal stem that stays hidden from view.  Cutting and applying herbicide above this branch could cause the treatment to fail and the rose to survive.  The horizontal branches also have the annoying habit of rooting at the leaf nodes so that a series of individual plants develops along the length of the stem.

I know the property will never be completely free of invasive plants, but it would be nice to reach a point where I could walk around without having their presence so obviously displayed everywhere I look.  As my supply of non-native invasive shrubs dwindles, the populations on neighboring properties is expanding, so new seeds will always be finding their way across the fence.  At one point during my work, I was thinking of one of my favorite books, The Day of the Triffids by John Wyndham.  I didn’t realize it when I read the book for the first time nearly 50 years ago, that the story is basically about a non-native invasive plant species that swarms over the countryside wreaking havoc on the human population.  At one point in the book, Triffids crowded outside barrier fences while the people inside hunted and destroyed any invading seedlings.  It was the scene just outside my fence line that brought that book to mind.  Of course, the invasive plants that I’m dealing with can’t walk and they’re not going to strike me dead if I exhibit a moment of carelessness.  That’s something I can be grateful for as I continue my work.

Eliminating Invasive Plants – Summer Activities

As the seasons change, my management activities change.  Summer is a time to hunt and eliminate invasive forbs and grasses.  Sweet Clover was my initial target several years ago.  As Sweet Clover numbers dropped, I added other species that could be controlled by pulling prior to setting seed.  Now, Yellow and White Sweet Clover, Wild Carrot, Teasel, and Oxeye Daisy are all on my summer pulling schedule.  Not all invasive species can be controlled by pulling.  Sometimes, like in the case of Crown Vetch, the aid of a chemical herbicide is necessary to eliminate the plant.

This is my second year using the chemical Clopyralid in the treatment of Crown Vetch.  Clopyralid kills only broadleaf plants, and is particularly effective on legumes.  Grass is left unharmed, so no bare spots are left in the field after treatment.  The areas I treated this year were fewer in number and much smaller than what I dealt with last year.  Shown above is the largest patch of Crown Vetch I had to spray this year, and it covered only about 40 square feet.

Crown Vetch found its way into my fields as seed that was produced along the edges our township road.  I eliminated the roadside vetch last year, but some of the affected field areas are going to take a bit more work.  Crown Vetch growing beneath the canopy of tall Indian Grass is hard to spot.  The best time to search is when the plants begin to flower.

Unfortunately, peak flowering time for Crown Vetch coincides with flowering of other lavender bloomed plants such as Monarda.  Shown above is Crown Vetch on the left and Monarda on the right.  Colors are almost identical.

Monarda flowers are held above the Indian Grass leaves.  Good luck trying to spot a couple stalks of Crown Vetch hidden down in the grass.

Johnson Grass is another species that requires some herbicide assistance if it is to be eliminated.  I’ve been after this species for several years and only found seven small clumps growing this year.

When dealing with Johnson Grass, I first cut the stalks down to a manageable height and trim back any long, flowing leaves.  This allows me to spray the complete plant with glyphosate, without spraying a lot of neighboring plants.

Johnson Grass is another invasive species that can trace its origin back to the roadside.  Even though the roadside along my property is free of this invasive grass, seed produced along other sections of the road are easily caught and transported by vehicles traveling the roadway.  I expect passersby will replenish my seed supply on an annual basis.

Johnson Grass is hard to miss when it sends up a flower stalk.  This species puts on height in late July, long before the tall prairie grasses, so it doesn’t take much searching to identify new infestations.

When the plant is blooming, tops can be cut and just left in the field.  There is no chance that these flowers will produce viable seed if removed from the plant at this stage.  If treatment is done after seed has formed, it is best to remove the seed heads from the field to eliminate any viable seed being left behind.

I began pulling Wild Carrot six years ago.  I’ve had a lot of success in reducing the numbers of this plant.

Areas that once yielded hundreds of plants, are now producing only a few plants each year.

With fewer plants to pull, I can cover more area.  This is the last of the Wild Carrot infested barrens, an area that I have never had time to get to before.  I was able to finish off this field just as the pulling season came to a close.

Wild Carrot seeds were just beginning to darken during my last week of pulling.  Not knowing if these seeds were developed enough to finish ripening on a pulled plant, I removed the seed heads and bagged them for disposal somewhere other than the middle of my field.

A single Black Swallowtail caterpillar was found on one of the pulled carrots.  I transplanted it to a domesticated carrot variety in my vegetable garden.  It ate for several days and then disappeared.  I hope it went off to find a secure place to pupate. 

Cycnia inopinatus Caterpillars

I’m always pleased when an uncommon plant or animal species shows up in unusually large numbers. This year, I am finding the caterpillars of the Unexpected Tiger Moth, Cycnia inopinatus, to be several times more abundant than they have ever been in any past year. Having a bright orange body decorated with tufts of black hairs, this species is hard to miss when it’s around.

The Unexpected Tiger moth is listed as an endangered species in the state of Ohio. Its caterpillars feed exclusively on milkweeds, with Butterflyweed, Asclepias tuberosa, probably being the most common host plant. So far this year, I’ve found caterpillars on Butterflyweeds scattered over about a 30 acre area.

In late spring and early summer I’ve seen the caterpillars feeding on Spider Milkweed, Asclepias viridis. Recently, I’ve found several caterpillars feeding on the leaves of Common Milkweed, Asclepias syriaca.

A five-year-old clump of Butterflyweed growing next to my driveway is currently hosting a half dozen caterpillars. Later this year the caterpillars will move into the leaf litter at the base of the plant and pupate. They will remain there through the winter and emerge as adults next spring.

The Common Milkweed being used as a host plant is growing at the edge of my water garden. So far, this is the only Common Milkweed plant that I have found hosting any Unexpected Tiger Moth caterpillars.

Oleander Aphids have been abundant on all of the milkweeds this year. Caterpillars seem to avoid leaves that are excessively covered with aphids and honeydew, but there are enough clean leaves that the caterpillars do not seem to be lacking an adequate food supply. I hope this abundance of caterpillars results in record numbers of adult moths next spring.

The above video shows some of the typical caterpillar activities.

Immature Cooper's Hawk

An immature Cooper’s Hawk has been hanging around beside the house for the past week.  Its usual perch is atop the stump of a limb rising from the body of a downed Silver Maple.  This puts the hawk in plain sight about 5 feet above the ground and 15 feet from my bird feeder.

Intermittent showers from the remnants of hurricane Irma have kept the young hawk looking rather bedraggled the last two days.

The hawk is vigilant about checking out any animal movement nearby.  A pair of Cooper’s Hawks has been hunting around the bird feeder for years.  It’s possible that this bird first visited here with its parents.

This may seem like the best place to sit and wait for a meal to come by, but it doesn’t work at all.

The above is a short video highlighting some of the hawk’s behavior.  Mostly looking and preening, with a nice tail fan in the last half.  The video was filmed from inside the house, so there are no interesting nature sounds to be heard.

Camouflaged Loopers

This is a perennial favorite of mine, Camouflaged Looper, the larva stage of the Wavy-Lined Emerald Moth.  There are two caterpillars in the photo, one to each side of the central disk.  Camouflaged Loopers commonly feed on the disk flowers of species in the Aster family, so spend much time exposed to view.  In order to look less like a tasty morsel to passing predators, this caterpillar adorns its body with bits of the plant on which it is feeding.  To the casual eye, it looks just like a part of the plant.

At Blue Jay Barrens, Orange Coneflower, Rudbeckia fulgida, seems to be the plant of choice for this species.  I encourage a large patch of Orange Coneflower to grow outside the front door of my house, so I can enjoy the Camouflaged Loopers through their entire season.

This looper was cleaning its mouth or doing some similar facial area grooming.  I gave it high marks for doing what I thought was a superb Godzilla impersonation.

The above video shows some typical Camouflaged Looper behavior.  If you turn your sound on, you will notice the chatter and buzz of Hummingbirds passing over my head.  My Hummingbird feeders are only about eight feet from me.  I posted a longer version of this film to YouTube which you can view by clicking HERE.

Solitary Sandpiper

Blue Jay Barrens is an excellent example of a xeric environment, meaning that the shallow, well drained soils cause the ground to be exceedingly dry.  It’s always a treat to see a visiting shorebird, since no shores occur here in a typical summer.  Solitary Sandpipers occasionally stop here, but this is the first time I’ve ever been in position to photograph one of these birds.

The flood of July 6 is responsible for a trace of the pond to still be present in early August.  It’s not much more than a large puddle, but it is the type of place a Solitary Sandpiper will go to forage for food. 

The bird seemed to be finding plenty to eat in the shallow water.  Most of what it caught was tiny, but a couple items were large enough that I could discern a dark form disappearing into the bird’s mouth.

Above is one of the videos I shot.  I spent about 20 minutes watching this bird.  Not once during that time did it give any indication that it was concerned with my presence.  About ten seconds into the video, the bird turns a quick 180 in response to a Mourning Dove winging just a few feet over its head. 

Silvery Checkerspots

I usually don’t see more than a half dozen Silvery Checkerspot butterflies at Blue Jay Barrens in any one year.  This has been a constant situation for over 30 years, even though we have an abundance of Wingstem, the Silvery Checkerspot’s host plant.  For some reason, Silvery Checkerspots are everywhere this year, and I am enjoying the spectacle.

A couple of days ago, I sat beside a patch of Orange Coneflower that was being visited by about a dozen of the small black and orange butterflies.  I just watched the show for quite a while before turning on the camera.  I had never had any luck getting a good photo of this species, but I knew that was about to change.

After a few minutes, the butterflies resumed their nectaring and chasing activities as though I was just another part of the landscape.  That’s one of the neat things about many animals.  Their brains don’t interpret inanimate objects as threats, so if you can get yourself situated without scaring them away, the animal will soon continue with its normal activities.

The above video shows an interesting behavior associated with nectaring on the coneflowers.  The butterfly would pivot atop the flower head and probe each open floret as it went.  Some butterflies turned clockwise, while others turned the opposite direction.  Individual butterflies that I followed from flower to flower, each turned in the same direction as it had on the previous flower.  My sample size wasn’t large enough to make any valid statistical conclusions, but I began to wonder if butterflies could be right-handed or left-handed.

Pulling Teasel

In an effort to eliminate invasive Teasel from my fields, I have taken time each summer during the past several years to remove the ripe seed heads from the Teasel plant.  Results have been positive.  The Teasel population is notably diminished over what it was just three years ago.  Instead of large Teasel patches, I now just have individual plants scattered around the field.  The problem with this control method is that the timing for Teasel seed head removal is critical.  Ideally, the activity should begin when the most mature seed heads are just a couple of days away from dropping their seed.  Beginning too late allows mature Teasel seeds to be lost during the collection process, giving rise to another crop of mature plants in two years.  Beginning too early allows for the possibility that the plants will produce new flowers that will mature before the end of the season and scatter new seed in the field. 

I was determining the progress of Teasel seed production and found most plants to be about a week away from releasing mature seed.  As I looked at the plants, I began to wonder how easily a Teasel plant would pull from the ground.  If I pulled the plant, I would not have to worry about it producing any new flowers.  Pulling would also allow me to begin work earlier in the year and increase my collection window from a few days to a few weeks.  I figured that pulling was worth a try, so I headed for the barn for a pair of heavy work gloves, an absolute necessity if you are going to grapple with a spiny Teasel stalk.

Despite its impressive root system, Teasel turned out to be fairly easy to pull.  There were a few that held tight, so I cut these off at ground level.  I’m betting that the root system won’t be able to produce a new mature plant before cold weather sets in.

The work of plant pulling went much more rapidly than seed head collection ever did and piles of Teasel plants began to accumulate on the trail between two fields.  I spent eight hours at the task and searched an area of about 12 acres.  Only about five of those acres actually yielded any Teasel plants.  I just wanted to make sure there weren’t any infestations that I had not yet discovered.

I learned one trick that came in handy, especially in the tall grass areas.  I left one tall Teasel standing in the area that I worked and piled pulled plants at its base.  I then moved on to the next section and did the same thing.  The standing plant allowed me to easily find my cut pile when I was ready to haul the plants out of the field.

This group of ten plants represented a new infestation.  Just beyond the trees in the background is the township road.  A culvert crosses the road at this point and dumps runoff water into the field.  Along with the trash and debris from the road are often a few weed seeds.

All of the collected plants were consolidated into a single pile.  The pile is located at the field edge next to my vegetable garden and is used as a depository for any noxious plants that may drop viable seed.  I pass this pile several times a week and will destroy any undesirable plants that try to grow here.

Even the most developed seed was not near maturity.  The seed shown here has shriveled considerably since the plant was pulled two days ago and may not be viable.

Several of the plants had played host to some type of stem borer.  The borer doesn’t seem capable of killing the plant before seed matures, so it is not likely to be valuable as a control method.

Tiger Swallowtail butterflies were especially numerous in the field.  I scared dozens from the Teasel as I worked.  Fortunately, there are plenty of native wildflowers that the butterflies like just as well.  Pulling Teasel and removing the entire plant turned out to be much quicker and easier than collecting seed heads.  I’ll definitely continue this practice in the future.  At least until I run out of Teasel.