Behold, I tell you a mystery...

I first noticed a little scrubby group of Norway maples on October 18th: many leaves had black splotches, and some of these black splotches had holes in the middle.  "Huh," I thought, "some sort of fungal disease."  It looked as though it was an infection spread by spores: one would land on a leaf, invade its tissues, and then proceed to spread outward in a widening circle.  I looked for it elsewhere, but found it only on a few leaves of the big Norway maple in my own backyard.  Since it seemed to be very local, and since I'm not very fond of alien invasives anyway, I gave it little further thought.  

 

What's this?  (11/18)

 

A few spots on our own tree.

The scrubby patch consists of perhaps a dozen saplings (the largest a dozen 

or so feet tall) on a neglected property line, along with one tree about a foot 

in diameter that still has its lower leaves.  (11/23)

But a few weeks ago I realized that, as the rest of the local Norway maples finished dropping their leaves, this little cluster still had most of its leaves; but, these leaves, though still green, had died, dried out and shrivelled up right on the twigs.  As I wondered whether this was caused by the fungal disease, I noticed that a lot of the dead leaves were unmarked by the fungus. 

Some leaves are infected, many are not, but all are dried out and dead.

A few minutes with a search engine brings up Tar Leaf Spot of Maple, which this resembles, except that tar leaf spot causes premature leaf drop--the opposite of the situation here.  Also, it seems to be a local infection--limited to individual spots on individual leaves--rather than the sort of systemic infection that might affect leaves elsewhere on the tree.  And none of the diseases I saw online mention leaves failing to drop.  Weird.

"Infant" Mortality

I've been teaching ecology to 9th- and 10th-graders lately.  While watching a video segment that featured young arctic fox cubs that depended for their survival on their mother's ability to bring home equally-cute snow goose chicks for dinner, I pointed out that, over the long term, both foxes and geese were likely to raise only about two offspring per couple to maturity over their whole lives.  That's the simple consequence of having a stable population: parents can only replace themselves--nothing else will serve.  Of course, that is the overall average over a whole population, over a long enough period to even out variations in resources, etc.  Even so, it is instructive to meditate upon: there are always more young born than can survive. 

In light of this fact, the overwhelming fecundity of trees is even more incredible.  Walking the dogs a few days ago, I found myself looking at a tiny bit of the vast untimely death that is a normal part of life.

Immature Norway maple fruits on sidewalk.

These winged fruits (called "keys') each contain two embryos.  They are only a fraction of the size they normally reach at maturity, so could not survive even if they had landed in a better spot.  Although it has been a bit gusty lately, I'm pretty sure they were aborted, rather than simply blown down.  I can't say why; their loss must represent a significant waste of resources for the tree. 

The only good I can see from such an event is that the tree's loss is inevitably someone else's gain; insects, worms, fungi and the like small creatures will feast on the keys for some time.  And, of course, natural selection could not perfect the Norway Maple Way of Life without the competition for existence that results from too many young competing for a chance at survival.

Don't worry--there're plenty more.

The Battle is Joined,

 

The Enemies: English ivy (above) and vinca major.

 the die is cast, I have taken the field, and there is nothing to fear but fear itself.  I have begun to kill alien invasives. 

This follows a decade of neglect that began when my old love of sailing reignited, and became a passion for boatbuilding and making small sailing voyages.  Since finishing a twenty-foot two-masted sailboat in 2005, I have built an eleven-foot pram dinghy, a sixteen-foot two-seat kayak, a fifteen-foot enclosed cabin pram sailboat, and a skin-on-frame single-seat kayak.  Along the way, I sailed every part of Narragansett Bay in Rhode Island, much of the south coast of Massachusetts and Buzzards Bay, and made several trips to off-shore destinations like Block Island, Martha's Vineyard and Nantucket, Provincetown on Cape Cod, and Montauk, Long Island.  I've paddled and sailed nearly the entire Taunton River  Many of these trips lasted several days.

And when I wasn't sailing I was planning to sail, doing boat-building or maintenance, experimenting with improvements in boat or gear, or simply dreaming of sailing or paddling trips.

But lately my attention has turned back ashore as sailing opportunities have been curtailed by my need for summer employment and the necessities of family life.

And so I have begun once more to take my Wild Place in hand. 

When we first bought the property over fifteen years ago I--in my pride of ownership and environmental consciousness--determined to make it a worthy bit of urban nature.   I tore up the garden strip against the south side of the house and put in native grasses and forbs.  The back woods were bigger, so a bigger challenge.  My whole attention at that time was to do mortal combat with the English ivy that covered everything, and I put time into the project over several summers.  Then I put a few meadow plants into one clear spot, hoping for enough sunlight to keep them alive. 

But the meadow failed, and the woods were gradually overrun by ivy, and now also vinca.

Now I know a bit more than I did then.  I recognize Norway maple as a true invasive (rather than just an alien nuisance), I have spotted European buckthorn out there, and I have watched the vinca invade more and more.  I am now ready to put the Nature back into it, though at the cost of losing the true Wildness.  It is going to be a "managed" or "modified" natural place.  

 

Results of early battles.

 

 Standing wearily amid the dead, sword (figurative) hanging limply at my side.

When is "Wild" not "Natural"?

Feeling a renewed proprietary interest in my little Wild Place, I am considering a plan to make it a bit more natural, if not wilder, than it is now.

The little bit of wood at the pointy back end of our wedge of land has little of beauty although the neighbors have a few nice trees.  Without any fence or other visible boundaries, I can enjoy the neighbor's trees almost as much as my own, they lending character simply by their nearness.  But two of the prettiest of these, twin red oaks of respectable size for the city, died some years back and both have fallen, leaving the lot more bush or scrub than woods. 

So I have decided to take it in hand.  Although the very definition of a Wild Place is one which is unkempt--not planted, landscaped, mowed or even raked--I think I can make a good case for intervention.  I reason thus: although Wild, my wood is no more than half native, being choked by at least three species of invasive alien plants. 

 

Norway Maple (Acer plantanoides)

First, there are the Norway maples, of European origin, first imported as street trees and still valuable for that purpose.  Norway maple (Acer platanoides) has three characteristics that make it dangerous in a wild setting: it casts very deep shade, so seedlings of other trees find it hard to get enough sunlight to survive; its roots are so close to the surface of the ground that they hog all the surface water, leaving too little even to grow grass; and it is prolific in reproduction, sending its children spinning down on their little wings to establish themselves in practically any environment.  Together, these talents spell TAKEOVER.  And that's pretty much what it has done on my land: many--especially of the younger--trees on my land are Norway maples.  I don't quite hate them.  No, not quite. 

 

English Ivy (Hedera helix)

The forest floor is dominated by English ivy that is as prolific in its way as A. plantanoides.  I first dealt with it by heroic efforts when we first bought the house.  This is the ivy whose climb up the brickwork of the hallowed halls of academia make them "ivy league."  If it simply stayed there, all would be well, but it has been spreading through the woods like Tolkien's goblins in the days of seeming peace, when I am lulled into a false sense of security.  English ivy (Hedera helix) also resembles A. platanoides in the depth and permanence of its shade: the plant has thick, dark green leaves that are evergreen. so that even the early wildflowers, with a strategy to emerge to capture sunlight through plants still bare of leaves, cannot get enough light.

 

Vinca minor

Another ground cover invading my land along a a broad front is Vinca (Vinca minor, I think).  It is coming in from the north edge, and is now advancing into the wood.  But it also got into my meadow garden, where I have worked each year to pull out any vines that dare to show.  I cannot eradicate it completely, since some of the plants are rooted in the middle of bunch grasses such as my big blue stem (Andropogon gerardii)--very secure hiding places, since I love my grasses.

 

European Buckthorn (Rhamnus frangula)

Finally, I recently realized I have a good many invasive buckthorn (Rhamnus) bushes in the woods.  Long ago I had misidentified it as a species in the Dogwood genus.  [Wrong again: it is in fact Gray Dogwood.]  I didn't paid much attention to them until I correctly identified it elsewhere as part of a biology review project, and then found it popping into my consciousness here at home.  I haven't yet tallied the number I have to deal with.