Middle Sugarbush Lake Deep

On the LakeGrade rubric, Middle Sugarbush Lake Deep pulls an A: clarity at 49.2 ft and phosphorus readings still being added put it in the top bracket for Wisconsin. Sub-grades cluster within a single letter of each other, which usually means the lake is in stable trophic balance rather than fighting one specific stressor.

A TSI value of 21 puts Middle Sugarbush Lake Deep in the oligotrophic range, where biological productivity stays low and the water column remains clear. The lake's 57 ft maximum depth is in the upper tier for Wisconsin — deep enough for cold-water fish to find refuge in summer. Middle Sugarbush Lake Deep covers 254 acres alongside partial shoreline records — a mid-sized water that supports a working fishery without being so large that conditions diverge between basins. Middle Sugarbush Lake Deep sits at rank 121 of 202 in Vilas County, in the lower half of the local distribution.

An invasive species record — Rusty Crayfish — has been logged at Middle Sugarbush Lake Deep; Wisconsin DNR maintains the official infested-waters list. The fishery includes walleye alongside the lake's other 6 documented species — a notable draw for Wisconsin anglers. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.