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Mariton: Time Lapse Freeze Frame

by Tim Burris, Preserve Manager.  Photos by Carole Mebus.

My management goals at Mariton are pretty much guided by Aldo Leopold’s essays like  Thinking Like a Mountain. I think I help the land by working to manage invasive plants, control erosion on trails, and other things. For the most part I observe what the forest does, or “wants to do” and go from there. Decades of observation have helped guide my management actions, and I think those actions make Mariton appear very natural.

One of the exceptions is my decision to manage four of the fields with annual mowing. I tell children and adults over and over that this part of the country “wants to be a forest”.  You can see that very clearly in three of the Mariton’s fields at this time of the year.

April 4, 2015

April 4, 2015

Carole took the above photo in April, five days after I had brush hogged it with the tractor. Below is the same angle taken 6 months later. In the foreground, and throughout the field, are the saplings of Wild Black Cherry (Prunus serotina), Tuliptree (Liriodendron tulipifera) and Sassafras (Sassafras albidum) that are literally 6 months old and 6 feet tall. If I didn’t mow this field every year, it would revert to forest in just a few years.  A forest would be fine, but I like the diversity that these fields lend to Mariton’s landscape – and I treasure this outdoor textbook on forest succession.

October 6, 2015

October 6, 2015

Going back to Aldo Leopold, two decades of mowing and watching the results of these fields allowed me to stay calm after Hurricane Sandy leveled large sections of Mariton’s forest. We still have lots of work to control invasive plants in certain sections of the affected areas, but the forest is well on its way to restoring itself. In the coming years, I plan to do some selective management with chainsaw and shovel to promote a diverse forest. Again, I will draw on years of listening and observing to guide those actions as I try to “think like a mountain.”

Paunacussing Preserve

(*Click on image to make larger)


Diabase Farm Preserve

(*Click on image to make larger)

Crow’s Nest: Ash tree survey

By Daniel Barringer, Preserve Manager

Or, the times they are a-changin’.

Emerald ash borer (EAB) is present in two of our neighboring counties, and ash trees are likely to disappear from most of our landscapes.

Ash trees that are growing along roadsides or near buildings are going to have to be removed so that they don’t become hazards. And there’s no way we can afford to do this on our preserves all at once. By the time we see signs of the borer exiting tree trunks the damage will be done. We are assessing the ash tree numbers, size, and priority for removal so that we can get a handle on costs.

Here intern Brittany Grabois is measuring the size of tree trunks as we collect GPS location data for the ash trees.


Crow’s Nest may have more ash trees to remove than many of our preserves, as we have several miles of road frontage here. Our survey found about 200 trees along roads here that will require managing, and we hope to spread that out over the few years remaining before they become hazards.

Of course this is just a tiny percentage of the ash trees here; those in the woods will be left to fend for themselves and will provide habitat for other species even in death. Our strength here is in diversity: ash trees will be missed but many other species will take their place.


Summerhill Preserve Kestrels 2015

American Kestrels in the nest box

American Kestrels in nest box
(photo – Ron Zigler)

By Mike Coll Preserve Manager

For the second straight year, the nest box at our Summerhill Preserve successfully fledged American Kestrels. This year there were four young.

This video shows one of the adult birds flying up to the box to feed the young (in slow motion):

Here you can see the young birds inside the box. They fledged from the nest less than a week after this video was taken:

Read more about our nest box installation at Summerhill Preserve (one of our nature preserves open by appointment) and the Kestrel population there in this June, 2014 blog entry.

Crow’s Nest: Visitor Center progress

By Daniel Barringer, Preserve Manager

The new stamped concrete walkway at the barn is finished. No, that’s not it in the photo below, that’s the old one, in a photo from the spring of 2001.


What’s amazing to me about the new walkway is two things: one, that it looks exactly like the old one—but is at a different grade to accommodate the lower entrance to the new wing (just visible to the left, below). Sharp observers will also notice that it grows wider closer to the doors, as we have been able to watch how the path gets used over the past fifteen years of programs here.


Second, all the work was done in just a few days from removal of the old walkway and completion and usability of the new one. The work was entirely fit into a small break between programs so there was minimal interruption.

Mariton: Chestnut Walk Rescheduled

by Tim Burris, Preserve Manager

American Chestnut

Mariton’s American Chestnut Walk has been rescheduled to the raindate of Sunday, October 4, from 10 a.m. to 1 p.m. Mike and Kieu Manes will lead us along Mariton’s trails to look at chestnut trees growing in the woods. You’ll learn about efforts to restore this remarkable tree, as well as see the things we are doing here at Mariton.

One of the man-made natural disasters of the 20th century was the inadvertent release of the Chestnut Blight that killed millions of trees in North America. At one time, American Chestnuts (Castanea dentata) made up 25% of many eastern forests. The trees grew quickly, but lived long. The lumber was used for remarkable furniture, along with rot resistant utility poles and barn beams. The nuts of the American Chestnut was staple for humans and wildlife. Passenger Pigeons, bears, turkeys, and deer are just a few of the animals that depended on this reliable and nutritious food source. Self-sufficient farmers gathered nuts for food, livestock feed and as a cash crop.

There is hope that humans can rescue the American Chestnut. That is an important goal as other species disappear from forests due to our careless introduction of forest pests and diseases. Learn about this relic and the dream for future forests on this walk.  Bring a lunch if you like, and we will eat along the trail.  Bring leather gloves and help us collect chestnuts for propagation.

American Kestrels Return to our Stroud Preserve

By Mike Coll, preserve manager

American Kestrel, Ron ZiglerThis year for the first time the walking trail through the “Bobolink Meadow” at our Stroud Preserve was closed to foot traffic during bird breeding season (April-August). This trail closure is one of a number of such closures aimed at protecting the breeding grounds of sensitive bird species. In this case the impetus for closing the trail was the breeding population of Bobolinks, a species that consistently nests in the grasses of this particular meadow. These ground-nesting birds can be negatively impacted by the proximity of humans and dogs (especially unleashed ones).

However, closing the trail appears to also have had a positive impact on another species in decline, the American Kestrel. Kestrels are also easily disturbed by humans and, although a box had been present for a number of years, I had never observed Kestrels nesting there until this year. The trail previously came almost directly beneath the box and likely was the reason they hadn’t used it.

Here is a video of the young birds (looks like 4) at just a few weeks old:

The continuing story of the Hildacy Screech Owls…

By Mike Coll, Hildacy Farm Preserve Manager

When I last wrote about the owls in the Hildacy nest box it was in March of this year and I was hopeful that the pair would attempt to breed again and would this time be more successful than they were in 2014. The pair in fact did make another attempt but unfortunately this year’s nest again produced no young.

The particulars of this year’s story begin with the female owl (the red phase owl) roosting in the box every day this spring except for one and on that day I observed the gray male owl in the box. I took this to be a sign that the pair had mated again and a week or so later the female began laying eggs.

However, unlike the previous year, this year I never saw the male owl again. The female, who should have been spending almost all of her time incubating the eggs (while being fed by the male), was instead forced to go out at night and hunt for herself. I once even observed her calling from the box, which is the opposite of the secrecy that birds usually display once they have laid eggs. My guess is that the male owl met an unfortunate fate. He may have been hit by a car or killed by a local Great-horned Owl, but it seems very unlikely that he would have abandoned his mate at such a crucial point.

When it became apparent that the male owl was not going to return, I made a somewhat futile attempt to act in his stead. Adult owls consume about one mouse per night, so I decided (after discussing the situation with wildlife rehabers at the Wildlife Clinic at the Schuylkill Center) that I would purchase frozen mice online (normally marketed to people feeding pet snakes) and supplement her diet the way the male owl would have. Each night I thawed out a mouse, waited for the owl to leave the box, and tossed the mouse into the box with the help of a long pole. It seemed like she started to expect these feedings and was able to spend much more time incubating and less time hunting. Eventually I decided that it would be less invasive to place the mouse out in front of the box and let her come grab it herself. Here is the slow-mo footage of her coming to get a mouse, captured with an infrared camera:

I continued feeding her for the better part of a month but the eggs never hatched and one day she simply abandoned the nest. I think it is likely that the eggs were either never actually fertilized by the male or that they were unable to survive the first few cold nights (before I started feeding her) when the owl was out hunting.

While this is obviously a disappointing result, I think it illustrates how precarious each year’s breeding cycle is. All factors must be accounted for in order for a species to successfully reproduce and many times this does not occur for one reason or another.

But, there is always next year and with that in mind I took the opportunity to replace the old box with a new more structurally sound version that also contains an upgraded HD camera.







The new camera has a larger bank of infrared lights, higher resolution and provides much more clear audio than the previous one.
After abandoning her nest, I didn’t see the owl at all during the summer. But a few nights ago I heard a Screech Owl calling from behind my house and then on 9/27 she spent the day roosting in the new box.

Hopefully, this owl will continue to use this box as a roost throughout the winter and then locate a new mate in the spring.

Crow’s Nest: Invisible Management

By Daniel Barringer, Preserve Manager


I tell our volunteers and staff that when we do our job well, it looks like no one was here at all. This is an area of the preserve where we have done extensive management removing invasive species and native wildflowers have filled in well.


The drying stems of Joe Pye weed frame the asters and goldenrod while alder, dogwood, and maples fill the background. I liken our work to editing (I was, after all, an English major). We remove those plants which are not consistent with our management goals, add a few others if necessary, and generally stand out of the way of nature taking its course. If we have done our jobs well our work is almost invisible.


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