The 10,000 solar panels the tree has worn since early spring are releasing their grip without a sound and spiraling to the forest floor. In deciduous plants, senescence means about the same as what it does in humans — the process of deterioration with age. Senescence makes me wonder what white-haired person is looking back from the mirror. Remaining on the branches, tight-fisted buds will be poised to unfurl into leaves next spring. Since the late 1970s, the University of Alaska Fairbanks Geophysical Institute has provided this column free in cooperation with the UAF research community.