Stacy Anderson takes a chainsaw to saplings in the way of a 3.8 mile portion of trail through Lake Kyle Natural Area that she and Benito Pereda have been tasked with clearing.

Spring is dawning at Lake Kyle Park, and the sound of the Kawasaki Gators driven by park staff scare up an occasional blue heron or red-tailed hawk beside the path along Plum Creek that will eventually be a part of a trail system allowing people to hike and bike from San Marcos to Austin.

The Emerald Crown Trail (ECT) is env...