March of Change

I haven't been into the woods much this winter, but for an occasional 30°+ chainsaw operation. Now, the growing day length, the day's work done, it was time to spread a bag of collected, mixed seed somewhere the sun may shine in the green season. 

The melt and evaporation is near constant, even on days well below freezing, but with this colder winter, refreshing snows were common. Now, with March's warm sun, the snow loses ground and the ground gains moisture. The thaw begins above, sinking into the earth, and its moisture mixed with mineral soil is a cold way to speak of mud. Mud is an element; we protect ourselves from it. In March, mud season begins in earnest, so a crisp mat of snow is a welcome traveling companion.

En route to the seeding region, snow delivered a graphic of animal traffic. The crossroads, the indecision, the quick and the casual are all written in the snow. I cannot fathom it, but isn't there a similar, but scented, pattern here only recognizable to those more dependent on the nose?

 

The wavy trail of, probably, a deer mouse on a journey of late winter courage as the red tail hawks and bald eagles glide high and the barred owls lurk mid canopy. 

By early March, ankle deep in snow, deer browse the dry, fibrous stems of the garlic mustard that they refuse to consider in the green season. Food of last resort, in winter, but never, not at all, when the buffet is so grand in May.

I did not understand how comfortable our mammal friends are with human paths before this place. I will take their cue as trails are altered by fallen timber, such as here. The trail used to pass to the right of this basswood, until it began to fall apart, completely blocking the old trail. The deer have made their decision; they now travel under the arch of a sibling basswood, the Arc de Ruminant.

In the late winter we take stock of the dead, the ill, the weak. The tops torn from hollowed basswood by time or wind, the snags of elder oak, rotted, but standing, the insect kill green ash and drowned every species in times of high water, are most evident in winter. Snags are important ecological components of the forest, whether killed by native or exotic means. For us, snags are question of safety, of food and shelter for wildlife, of timber taking out healthy neighbors. Few nearby young come out unscathed when elder trees fall and fall they do.

Of the remaining oak giants, red and bur of about a dozen on the drier, south facing slopes, we feel concern. These trees are one hundred forty, one hundred sixty, or more years old based on the rings of smaller felled oaks. They may outlast me, or not, but the point is not to count on a static nature, that is not what nature is.

As spring approaches I ready myself for the multitude of upcoming tasks and adventures. Many house and landscape projects remain, including seeding thousands of native woodland plants and harvesting two plots of Hudson Clove garlic, but also new opportunities. I have several upcoming photography courses at the Minnesota Landscape Arboretum that are filling up with those eager for something new from somebody new. I am also going to be working with scientists over the coming year, as artist in residence, at the highly regarded research landscape known as Cedar Creek Ecosystem Science Reserve. I plan to blog from Cedar Creek, nine square miles of otherwise inaccessible nature at the junction of the prairie, eastern deciduous and boreal forest. Stay tuned.

Gardening The Woods

There may have been a moment (or two) when I looked at my field of garlic, its plethora of weeds, its need for harvest, or even the bare soil in need of turning, and felt overwhelmed. Gardening the woods doesn't meet that level, it exceeds it. It is farm work spread over a decade -or more. In spring I garden the garlic mustard and in fall, I start on the buckthorn.

I refer to this process as gardening because restoration is a fallacy. There will be no restoration, only limited choices, however informed by research and good intentions. My work amounts to weeding, seeding, planting, observing and acting like any gardener would. My preference for plants native to this biome is practical and aesthetic. Practical because they are survivors that, once established, do not require my care. Aesthetic because they become part of the whole and offer surprises. I like the unexpected.



The oldest buckthorn trees line the edges of the sunny, wetland clearings where birds congregate and eat from a quantity of berries. Under roost trees, seed density can easily reach several hundred per square meter and sapling density averages 100 per square meter. As the birds move through the woods, so do their droppings. Consider the image, above, a map of bird roost sites, droppings turned young saplings in a green stream flowing north.

This panorama shows the stream of saplings progressing northward from the great wetland. It follows the bird flight pattern, but also the soil moisture of a seasonally flooded depression that in turn takes out trees that enables sunlight to hit the forest floor, increasing germination and growth. Yes, the buckthorn does grow up the slopes, perpendicular to the stream, but sporadically compared to the edges of the vernal pooling. However, in time and without my gardening, the whole of the area will become a thicket as these saplings mature and produce berries to seed the slopes.

It is early November, when all native deciduous plants have dropped their leaves in preparation for winter. This makes it simple to identify the greenery above as 100 percent buckthorn. On this southern slope, descending to the great wetland, the age diversity of buckthorn increases dramatically, topping out at mature, multi-stemmed, 25 foot trees at the wetland edge. Why such an incredible age difference merely 40 feet away? It may be because our woods have seen several mature oak trees come down over the last twenty five years, opening light to the forest floor and eliminating a thick cover of oak leaves that studies suggest limit buckthorn seed germination. More sun has broken the lowland canopy as our once considerable bank of green, black, and white ash trees die off due to emerald ash borer spreading since 2002. Dead or alive, felled trees take out additional trees as they come down, further enhancing the light hitting the forest floor.

An impenetrable thicket wasn't on this slope ten years ago. In summer, 2012 a thunderstorm took out two large oaks that were, maybe, 150 years old each. In five years this is what has become of the buckthorn seed bank.

The reason for Rhamnus cathartica's success? It outcompetes in photosynthesis, carbon gain, shade tolerance, light tolerance, moisture tolerance, earliest leaf out, latest leaf senescence, seed production, female to male ratios, age to fertility, germination rates, and mortality. It also germinates well in the particularly barren late summer soils of our mature forests, a by product of non native earthworms and growing deer populations. It's leaves are higher in nitrogen, decompose faster, and are eaten by the worms first, quickly cycling nutrients under buckthorn stands. It has no issue with anthropogenic disturbance. This plant does not create thickets in its native ranges, but it does in the midwest where it responds to fertile, calcium rich, mineral soils. As plants go, buckthorn has a lot going in its favor.

So why go after it? Why commit so much time and labor to removing it (no easy task)? Again, I liken it to the garden. Imagine your garden was only hydrangea, everywhere hydrangea, but this hydrangea never flowered and had thorns. Who would want a garden like that?