We went out for a hike this morning with that question in mind, and we came up with two signs of spring. The first is the amount of activity out in the forest: there just are more birds around (in particular) being busy than there are in winter. We heard two woodpeckers (caught sight of one, a little black-capped guy), and saw plenty of busy chickadees and such.
The second sign is this:
That's the Cascades this morning.
At 9 am, it is 30 degrees and rising.
Humidity of 44% and falling
Barometer is at 30.25 inches and steady under clear and sunny skies
The brook is running at 5 inches even.
A hike up the steep section of the Cascades trail and then on over the Newton trail today shows that we need to get up there with a bow saw; there's definitely a bit of clearing to be done on the slope, and then a whole section of tree across the Newton Trail. In the meantime, try to go over or through the trees rather than around them, as the bigger the trail gets, the worse the erosion.