TUCSON, AZ (Tucson News Now) - For the fourth year in a row, beginning Thursday, Aug. 17 the Saguaro National Park will resume aerial spraying to control buffelgrass in areas of the park that are not accessible to ground crews.
According to a SNP release, the south side of Panther Peak in the Tucson Mountain District (west) and the Tanque Verde Trail in the Rincon Mountain District (east) will be closed temporarily for 2 to 3 days in each area, while spraying is done.
Aerial spraying is done via helicopters to treat dense patches of the invasive plant, buffelgrass during the monsoon. Weather conditions, wind speed and direction are considered, according to SNP officials, before spraying is conducted to make sure the spray hits only its intended target - buffelgrass.
"The park waits for conditions to be as optimal as possible before resuming herbicide application," according to Leah McGinnis, Superintendent of Saguaro National Park. "The treatment works best when the grass has greened up and is actively growing after the monsoon rain has begun with very little wind."
Updates providing locations of closures due to aerial spraying will be available on the park's website: www.nps.gov/sagu.
The prescribed treatment of buffelgrass is within guidelines approved by the National Park Service in 2014 as part of a Restoration Plan and Environmental Assessment which included aerial application of herbicide to control invasive, non-native plants in places that are unsafe or too remote for control by ground crews. Ground-based crews and volunteers will continue to control undesirable plants in accessible areas with manual pulling and herbicide from backpack sprayers.
Buffelgrass spreads exponentially, and significant efforts are required to reverse its expansion. It crowds out native plants and can pose a serious fire threat, not only to desert plants like the saguaro, but also to homes and property. In 2012 when the park was last mapped for buffelgrass infestation, there were approximately 2,000 acres of parkland with the invasive grass. Last year, approximately 400 acres of buffelgrass-infested park lands were aerially treated with herbicide and follow up monitoring has indicated a significant decrease in buffelgrass in treated areas.
Additional information on buffelgrass and the threat it poses to the park, as well as the park's Restoration Plan and Environmental Assessment, are also available at: https://www.nps.gov/sagu/learn/management/restoration-plan.htm and https://www.nps.gov/sagu/learn/nature/buffelgrass.htm