Final answer:
The name of the woods that enclose the valley is Woodland Vale.
Step-by-step explanation:
The name of the woods that enclose the valley is Woodland Vale. In the given passage, the author describes the valley and its surroundings, mentioning the terrace fringed by silver spruces, the aspens in the wider terrace, and the center of the valley being a level circle of oaks and alders. These descriptions indicate that the name of the woods is Woodland Vale.