By Greg Lecker
Chattering red squirrels and cackling Pileated Woodpeckers accompany my walk on wood chip trails. Dozens of freshly dug small holes remind me that the soil surface in open areas is still warmer than shady areas. This week’s rains may even “green” up some lawns. It is overcast, but fairly comfortable for exploring. Gloves are un-needed since it is calm and dry today. As I walk around Green Heron Pond, I check the calendar date on my watch. Yes, it’s almost mid-December; and there is open water around recently completed renovations – footbridges, cut cattails, and new paths and plantings. Water in many areas that was frozen weeks ago has now opened up.
The bog plantings include tamaracks, meadowsweet, and white cedar – the latter is encircled by wire cages to protect it from deer browsing. The walking path is corrugated with short logs laid side to side; and it is packed with wood chips.
I step off the boardwalk and travel through the tall rushes and cattails that border the open water on the east side of Green Heron Pond. In the relative shade of the tall vegetation, this wood chip crunches slightly underfoot.Here I find evidence of the Albedo Effect. From a Latin root meaning “white” or “whiteness”, the Albedo Effect describes the phenomenon that light colored surfaces reflect light and heat, and dark surfaces absorb light and heat.
Plant stems lie crisscrossed in a frozen net. Around each stem, the ice has melted away. The Albedo Effect also applies to tree trunks and edges of parking lots. Meteorologists use the term “Evergreen Effect” when describing the effect that darkly colored northern Minnesota conifer forests produce in late winter – melting snow faster than open areas.
Along the wood chip paths on either side of the Green Heron Pond dock, I find green moss and duckweed locked in place.
Looking into reflections below a Tamarac tree, I am transported into an “Alice in Wonderland” mind-set – uncertain whether I’m looking up or looking down.
Bracing my camera on a butternut tree in the low light of the hillside, I capture the frozen flow of water into a Green Heron pond.
Sensing a chill on the north of the hillside, I turn to leave. Inside the visitor center’s Snyder horticultural library, “A Gathering of Flowers” showcases a collection of botanical themed ceramic tiles. This and many holiday offerings await Arboretum visitors this December.
Greg Lecker is a Minnesota Master Naturalist Volunteer.