Monday, January 14, 2013

WHAT A STEWARD SEES - January 2013

Each cold walk at Somme surprises us with something new. 
In winter we see the ecosystem's bones and learn about essence.

The white area burned last November. Tall orange grasses in the distance were protected by a firebreak. 
The unburned pale in the foreground is a weak community of weeds, without enough fuel to carry fire. 
A few years hence it will look orange and thick, like the rich grassland in the distance.
Snow where the grassy Swale Pond burned reveals a nearly complete circle of dark hummocks, 
built up by ancient tussock sedge plants. In summer, I'd stumbled over them 
in the lush vegetation without realizing that they were in a circle. Now the structure emerges.

All summer 
the Swale Pond looked 
like a field of tall grass. 

But now - burned - 
(and in between snows)
the bottom is strewn 
with the shells of tiny clams 
and many kinds of snails

Although still dry, 
the shells now show more clearly 
the pond's true character.

 Damage to hydrologic structure is easier to see in winter as well. When we look at burned Vestal Grove, we notice a ditch dug by farmers who owned this land for the century-long gap between ancient nature and forest preserve. Why dig a ditch in the woods? Probably to improve pasture. These woods supported cows and horses then. To restore nature now, should I take my shovel to that ditch? Natural hydrology can help the ecosystem recover.


In winter, rabbits and deer eat a lot of bark. For the deer, that bark is mostly in the form of live twigs ("browse"). For rabbits, it's mostly the bottoms of trees and shrubs, like this indigo bush. Note that four stems are entirely cut off. The other two have little left. This shrub will have to start again next spring with new shoots.

This bur oak was caged to protect it from the deer.

Most parts of the preserve have no bur oak reproduction even though bur oak was the main original tree here and over large areas.

But look down; the deer cage didn't protect this one from the rabbits.

This close-up
shows the rascals' handiwork. A trunk can recover from a little nibbling, but too much will kill it.

Here an oak has had some protection added.

The rabbits won't reach it now.

As with the clam and snail shells, 
the calcium of deer antlers 
survives as reminders
of the once living thing. 

The same animals 
that bite oak trunks have gnawed off the tips - recycling antlers 
to build their own bones and teeth. Calcium supplements. 

Other calcium that you might 
expect to be very fragile 
survives the winter. 
I was surprised 
to come across 
these mallard egg shells, 
left over from the drama 
that was the subject
of "Egg Blog" (May 16, 2012).
They seem so fragile. Their insides are still lined with bits of eggy stuff. Nothing has seen fit
to destroy them
after all these months?

Why a sharp line separating snow and no snow? It's the same line that divided this fall's burn (top right) from "no-burn" (bottom and left). A few inches of snow quickly melted wherever the standing vegetation absorbed the sun's rays and spread heat. Where the snow reflected radiation back to space, less melting (and less global warming).

What we notice of the bones and essence of the ecosystem keeps us thinking. In time it helps us learn how to be good stewards of nature, the planet, and ourselves.


Anonymous said...

-I like the dead tree in the first picture. It is amazing how quickly they decompose when you watch them. I often watch trees decompose out of respect rather than any innate interest. I realize a falling tree can kill and give the giants their due space until they fall.
-I also like the picture of the mallard eggs with all the bryophytes. Bryophytes seem to be lacking in your other pictures. I wonder how the nest might improve conditions allowing the bryophytes to develop.


Rob Liva said...

The Vestal Grove trench is intriguing -- in your time exploring the site's intricacies of time and space have you seen other signs relating the narrative that the land was a pasture for grazing?

In working in Kane County along a degraded creek I find various species of Ribes and Smilax, unpalatable to livestock and deer alike. Similarly Crataegus mollis, a species listed by Swink and Wilhelm to appear in overgrazed pasture. Taken within the context of historic imagery showing sparse trees on a nondescript creek bank I believe that the property was formerly grazed pasture -- what other signs might I look for?

Regarding your hypothetical to bring shovel to trench, after walking Vestal Grove with you this past fall the vegetation appeared most dense, a dozen species/square foot. Could moving the soil at this stage bring more harm than good?

Stephen Packard said...

Rob, thanks for fine observations and questions. Prairie wildflowers mixed with poverty oats and bluegrass rather than prairie grasses suggest grazing. But I have two foolproof ways of knowing that this site was pasture. First, the 1938 aerial photo shows cattle trails through the "rough" land between the crop fields. Second, I actually interviewed the former farmer who talked about grazing it.

Yes, it would damage some of the rich plant life to restore more natural hydrology with a shovel. But for the long term, I believe the benefits of natural hydrology would far out weigh the temporary damage.