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Nature Frosty Slough

Photo Story: Frosty Slough

It was about 8 am and 10 degrees above zero in our valley by the Bryant. You could see it was cold by the mist rising from the slough. (We pronounce slough as "sloo"). The warmer water evaporates as mist into the much colder air. Many years ago the slough was the main channel of the Bryant. Then the river meandered east. The cut-off slough became a narrow half-mile long pond, deep in places, swampy in others. 
A line of frost along the edge of the slough. Springs on the hillside keep the slough from freezing in the winter. They also keep it chilly all summer long. 
Heavy frost forms on cold grasses and stems on the bank.
A stem sticking above the water surface grows frost crystals.
Brilliant green watercress,
and light green duckweed keep growing in the 10-degree air. The warmer water keeps them from freezing no matter how cold it gets outside!