Football League. Since 1977, Missoula has also held "Maggotfest," a festival-style rugby tournament hosted by the Missoula All-Maggots Rugby Club the first weekend in May. The non-elimination tournament focuses on the fun aspect of the game, attracting 36 teams (male and female) from around the United States and Canada. In regular season play the Maggots compete as part of the Montana Rugby Union. Also in rugby are the University of Montana Jesters. Parks and recreation Missoula's location in a river valley surrounded by mountains on all sides as well as its history has had an influence on the development of the city's parks and recreation activities. Today the city boasts over 400 acres of parkland, 22 miles of trails, and nearly 5000 acres of open-space conservation land. Located at the confluence of three rivers (the Clark Fork, Bitterroot, and Blackfoot), the area is also used for white water rafting and, thanks largely to the novel and subsequent film A River Runs Through It by Missoula-native Norman Maclean, is well known for its fly fishing. Additionally, Missoula has two aquatic parks, multiple golf courses, is home to the Adventure Cycling Association, and hosts what Runner's World called the "best overall" marathon in the nation. With no recreational additions, the nature park has long been considered a wonderful place for birdwatching with over 100 different species that can be frequently sighted from the Bolle Birdwatching trail. A system of public parks was developed in Missoula in 1902 with the donation of 42 acres along the Rattlesnake Creek for Greenough Park by lumber baron Thomas Greenough and his wife Tessie. They simply asked that "the land forever be used as a park and for park purposes to which the people of Missoula may during the heated days of summer, the beautiful days of autumn, and the balmy days of spring find a comfortable, romantic and poetic retreat" with a follow-up nine years later in a letter to the Missoulian stressing his interest in having the park remain in as close to a native state as possible. Today, that request along with the discovery that non-native Norway Maples were inhibiting the growth of native trees and shrubs such as cottonwoods, ponderosa pines, Rocky Mountain maples led to the controversial decision to remove the invasive tree from the park with the hope of returning it to its natural state. In 1924, Bonner Park was created