Field Notes: Rain
~ by Jim Eagleman
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Water that is condensed from the aqueous vapor in the atmosphere and falls to earth in droplets” is the definition of rain. Measured at 1 / 50 of an inch by scientists, you may have wondered what else raindrops( in massive quantities) can do beside water plants, wash out driveways, and raise humidity.
Recent deluges have made life more challenging in Brown County. Highway workers remove fallen trees. Culverts are cleaned and repaired, and loose gravel regraded. More rains have caused power outages. Creeks and lakes are at flood levels. Residents remark it is the wettest spring in several years. Annual rainfall in Brown County is 40.6”, accumulating from all kinds of precipitation: snow fall, mist, fog, drizzling rains, and severe storms. We have already passed that mark and we’ ve only just reached the summer solstice.
My morning walk through our woods after an all night rain is refreshing and my senses are peaked. The air is clean and rich with aromas reminiscent of greenhouses and tilled garden soil.
Swaying branches overhead cause water to fall like soft, pelting hail on leaves.
Still dripping from run-off with drops falling on my shoulders, leaf shapes help rid surface areas of excess water.“ Drip tips” on the ends of most leaves, whether compound or simple, shed rain with air movements. Leaf stems act as pivot points, slightly allowing the broad leaf to turn. Some trees like our native Black Gum( Tupelo) and the domestic Rhododendron have thin, waxy coatings on their surfaces to prevent too much moisture on leaves. Falling through the leafy canopy, understory, and eventually to the ground, raindrops are absorbed below the surface by a thick mesh of criss-crossing root hairs from multiple trees. Last year’ s leaf litter retains moisture and helps keep soils from drying out.
A spikey, wet grey squirrel, resembling a punk rocker, jumps from a branch overhead, sending more droplets down on me. It emerged from its overnight shelter, a pileated woodpecker hole near a broken limb. Other rodents, like chipmunks, deer mice, and whitefooted mice use underground runways and dens to wait out the storm. Brush piles act as meeting places for other critters: songbirds, insects, and an occasional rabbit. A small garter snake
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