On a recent winter hike at Eagle Marsh we noticed numerous sparrows foraging for seeds amongst the skeletons of last seasons' native grasses. They would occasionally perch on the coppery-colored stems of another plant skeleton scattered here and there amidst the grasses.
Closer inspection revealed a plant with lance-shaped leaves, a stem with swollen areas at leaf nodes (where leaves originate)...
...and thin, papery sheaths at the base of the swollen nodes:
Taken together, those field marks told us that the sparrows' perch of choice was a variety of Knotweed, a.k.a. Smartweed, a.k.a. Buckwheat. We prefer Knotweed because this name recalls the distinctive field mark of "knotty" stem. The taxonomic family name is Polygonaceae. We'll remember this one and look at it again during the growing season when we can observe the flowers and get a positive i.d. to the species level (yeah, we look forward to such things!).
Not much further on our hike we came across another snag of old weeds that was a decent enough perch for a Marsh Hawk (Northern Harrier)!!
Apparently, many Eagle Marsh winter residents frequent the remains of last years' sea of vegetation. Food, shelter, cover - probably all of the above and many more reasons we couldn't even guess:
Many hikes end up having a theme and the theme today was something along the lines of "the value of vegetative dormancy to native fauna". Case in point - a flock of tree sparrows taking cover in a dormant oak branch:
A closer look. This little one was using this branch for a perch and the foliage for cover while waiting his/her turn to...
...feed on seeds revealed under a melting patch of snow!
Never a dull moment on a nature hike!