The state legislature chartered the university in 1869 as a land-grant university under the 1862 Morrill Act, two years after Nebraska became a state. At the turn of the 20th century, the university expanded significantly, hiring professors from eastern schools to teach its new professional programs and conducting groundbreaking research in agricultural sciences. The "Nebraska method" of ecological study developed during this time pioneered grassland ecology and laid the foundation for research in theoretical ecology for the rest of the century.