Hobo Cedar Grove Botanical Area, Protected botanical area in St. Joe National Forest, Idaho, United States

Hobo Cedar Grove is a 240-acre protected area in St. Joe National Forest where Western Red Cedar trees grow over 100 feet tall, surrounded by Oregon boxwood and Lady-fern plants. The landscape shows a mix of densely packed trees and understory vegetation in a moist woodland setting.

The grove was designated a National Natural Landmark in 1980, recognizing its old-growth Western Red Cedars estimated at around 500 years old. The designation protects a 240-acre (97 ha) stand within the St. Joe National Forest near Clarkia, Idaho.

The name "Hobo" refers to the hobos who once rode the freight trains of the St. Joe River valley and camped in this grove. Visitors today follow a self-guided interpretive trail with numbered signs, resting on cedar log benches along the route.

Two connected walking trails totaling 1.5 miles guide visitors through the woodland, with numbered signs identifying plant species along the way. The well-marked paths allow visitors to explore the vegetation at their own pace and learn more about forest structure.

The cedars here are estimated to be 500 years old, meaning some took root around 1500, before Europeans reached what is now Idaho. The grove was designated a National Natural Landmark in 1980, and a self-guided interpretive trail runs over a mile and a half past cedar log benches.