Her conservation efforts and fight against New England's "Timber Barons" succeeded in protecting thousands of acres of old-growth forest in the White Mountains.

Katherine's grandfather, John Sherburne Sleeper, was a sailor, shipmaster, children's book author, journalist, newspaper editor, and politician.

[3][15] That August, Appalachian Mountain Club (AMC) President Charles E. Fay and Councilor William Ladd stayed at the inn during a visit to the area.

Katherine believed that the town of Birch Intervale, which was nicknamed "Poverty Flats", could be revitalized by accommodating a tourism industry that had yet to exist in the White Mountains, and thus invited the visiting AMC officers to meet with local landowners at Wonalancet Farm.

[7] At this meeting, Katherine explained the AMC's work in creating trails throughout the country to locals and pitched the idea of clearing a hiking path from the village to the summit of Mount Passaconaway.

[3] After persuading the town, Katherine organized the AMC leaders and a group of local farmers to meet a few days later to work on the proposed Dicey's Mill Trail path.

[10] In the subsequent years, Katherine organized efforts to clear and beautify residents' properties, repair the town's roadways, and renovate the local chapel.

[11][16] Katherine's encouragement of tourism showed its value within months as the trails found immediate success with reporters beginning to praise Wonalancet Farm as a worthwhile Summer destination.

"[18][7] The WODC cut paths, created maps, set guide boards, planted roadside trees, and established a campsite at the foot of a nearby mountain.

[19] The pair hosted and sponsored winter sports and activities, such as Arthur's pastime of dog sledding, long before other destinations in the northeast.

[20] The sustained fame of Wonalancet through to the modern day is in part a result of Arthur's renown and the notable impact he had on sled dog racing in New England.

By the 1880s, rural residents of New Hampshire were becoming increasingly alarmed by the widespread clearcutting and wildfires caused by unsustainable logging by New England's "Timber Barons" and the expansion of railroads through the state.

Hot coals and sparks from neighboring railways, which were laid to transport the newly cut lumber, would then ignite the readily supplied kindling.

The White Mountains National Forest did not initially include the lands north of the town, known as the Bowl, which were the most popular to both residents and visitors.

She went to meet with the president of the Publishers Paper Company, who owned the area, and succeeded in persuading him to grant her an option on 3,000 acres (1,200 ha) in and surrounding the Bowl.

The price of the region made it undesirable to the Forest Reservation Commission, but the WODC, Katherine, and countless other clubs and individuals succeeded in the protection of the Bowl.

[3] Katherine and Arthur ran Wonalancet Farm until the 1930s when they began facing financial difficulties due to the Great Depression and the automobile's impact on travel.

[10] Some sources instead claim that the couple's relocation was a result of Katherine's health deteriorating to the point of her becoming incapable of running the farm while Arthur was on an expedition to Antarctica.

This effort led to conservationist groups securing thousands of acres for the White Mountain National Forest and her successful protection of the Bowl.

Rich, who had been an 1899 visitor to Wonalancet Farm and later became a wealthy patron of the Wonalancet Out Door Club and White Mountains National Forest, said:[28]"Wonalancet is not a geographical expression, it is a spirit, and it owes its existence to a young woman who came here twenty years ago – Miss Katherine Sleeper"In 1958, Majory Gane Harkness, about the significance of Katherine's arrival, wrote:"[...] she was practically the first outsider of either sex when she settled in this pocket of the hills in 1890, as well as the first inhabitant with a talent for organizing, and further, that she was a woman of exceptional charm and originality no matter in what society she might be placed.