Given the task definition and input, reply with output. In this task, you're given passages that contain mentions of names of people, places, or things. Some of these mentions refer to the same person, place, or thing. Your job is to write questions that evaluate one's understanding of such references. Good questions are expected to link pronouns (she, her, him, his, their, etc.) or other mentions to people, places, or things to which they may refer. Do not ask questions that can be answered correctly without understanding the paragraph or having multiple answers. Avoid questions that do not link phrases referring to the same entity. For each of your questions, the answer should be one or more phrases in the paragraph, and it should be unambiguous.

Passage: As the timber was exhausted and the land burned, many companies abandoned their holdings. Conservationists such as Joseph Rothrock became concerned that the forests would not regrow without proper management. They called for a change in the philosophy of forest management and for the state to purchase land from the lumber companies. In 1895, Rothrock was appointed the first forestry commissioner in what became the Pennsylvania Department of Forests and Waters, the forerunner of today's Department of Conservation and Natural Resources (DCNR). In 1897, the Pennsylvania General Assembly passed legislation that authorized the purchase of "unseated lands for forest reservations", and the first of the Pennsylvania state forest lands were acquired the following year.The state first bought land that became the Moshannon State Forest in 1898; the second purchase, and first in the Quehanna region, was 3,263 acres (1,320 ha) in the Three Runs area, acquired for $1 an acre ($2.47 a hectare) in 1900. Three smaller state forests (Karthaus, Sinnemahoning, and Moshannon) were merged to form the present Moshannon State Forest; in 1997, the forest covered 131,622 acres (53,266 ha). The first purchase for the Elk State Forest was made in 1900, and by 1997 it encompassed 197,729 acres (80,018 ha). Forty-six percent, or 22,179 acres (8,976 ha), of the total 48,186 acres (19,500 ha) of Quehanna Wild Area lies in the Elk State Forest. The remainder lies in the Moshannon State Forest.The state established a tree nursery in the Moshannon State Forest in 1911, which became the largest in Pennsylvania before it closed in 1980. In addition to planting millions of trees, in 1913 the state encouraged use of state forest lands by allowing permanent leases for camp sites; when the state stopped issuing new permits in 1970, 4,500 campsites had been leased. The Pennsylvania Game Commission began purchasing land for state game preserves in 1920, and by 1941, State Game Lands 34, which is partly in Quehanna Wild Area, had been established. Despite these conservation efforts, major forest fires swept the Moshannon and Elk state forests in 1912, 1913, 1926, and 1930, and minor fires occurred in other years.
What group called for a change in forest management?