PENNYSTONE • RESOURCES • NOTEBOOK
Viewpoint: thoughts on sustainability
Sustainability, like recycling, can become mired in absolutes, hair splitting and conditional requirements. The discussion becomes so complex and technical that it discourages, rather than encourages, the individual to embrace its merits.
Let's make sustainable simple.
In nature, ecosystems have evolved to be self-sustaining. An incredibly complex collection of living things in forest, meadow, swamp, even desert, keeps everything running smoothly and in balance. Gardens are by definition artificial; we alter the environment for our needs and interests. To pull that off, we have to help sustain it.
The solution? Seek and use native plants appropriate for your garden. They'll thrive and won't require the kind of chemical care and groundwater draw that strains the environment, pollutes the waterways, and ultimately plays havoc with ecosystems somewhere else.
Some wildflowers have enormously wide ranges, but even then stock should be chosen from similar provenance because there are localized adaptations. Others are highly specific in their need for a specialized combination of light, water, shade, soil. While it's possible to make some accommodations, it's also good to remember that the further you stray from what's natural, the more effort will be required to support the plant, reducing sustainability.
Carex pensylvanica in bloom. This sturdy grass-like low-growing sedge prefers shade, poor soil, dry acidic forests...and it spreads. It's a much better alternative to "shade" lawn mixes.
If it sounds too restrictive, consider a dry upland forest with very rocky, sterile soil, dappled to full shade, and erratic weather. A search for native plants appropriate for the region and commercially available turns up "only" 215 species in an array of sizes, colors, bloom periods and relatively easy to grow.
If dry ridgetops are "limited," then mid- and downslope forests are better still. Here there are seeps, springs and groundwater runoff to conspire with astonishing piles of "duff" - the litter of a woodland, which includes leaves, twigs, the remains of annuals, moss and even entire trees, all in various states of decomposition. A forest is a messy place.
When the path of litter moving downslope is blocked by surface boulders and logs, pockets of very nutrient rich and moisture conserving organic matter collects and creates sustainable habitat, especially when water oozes from bedrock or slithers down rocky slopes during rainfall.
Among the benefactors of pockets of leaf litter and the resulting rich soil are Mitella diphylla, which cheer us in early spring through wispy displays of tiny white flowers.
When late fall and early spring winds blow through dormant forest, legions of leaves embark on tumbling, swirling marches in search of the eddies that form on the leeward side of any barrier, but especially in thickets. Here we find blankets of patiently gathered duff and if we peek at the surface of soil below we see an active layer of leaf mold, decomposed matter, and rich organic loam. Along the way we notice how wet the leaves become, even during prolonged dry spells. This is nature doing sustainable landscaping.
Below the surface are the sands, gravels and channers of all kinds of rock. Shales and sandstones (rarely granite in these parts) create acidic soils and limestones form more circumneutral loams. This defines habitat for specific families of plants and the tree canopy often provides important clues.
The lower we travel on the slope, the richer and very often deeper the soil becomes, especially with its ability to collect and hold water. But along the way we sometimes encounter coves: sheltered places where organic materials and moisture often gather to create exciting and self-sustaining habitats for a wide array of species that normally shun the brutal climate on the open ridges and especially ridgetops.
Each of these provides useful models for our own gardens. On larger landscapes, it's usually easiest to work with the existing habitat, perhaps indulging in a tweak here and there to expand our horticultural range. But the landscaper working with a smaller space, ideal for retreat spaces and personal sanctuaries, can easily move a sufficient amount of rock and earth to mimic habitats of much greater scale and certainly plant opportunities.
Either way, the forest mechanics take over. Sustainability rules. It's as simple as that.