Management of flood-plain vegetation, 1967 to 1972, San Carlos Indian Reservation, Arizona

Abstract

This report is one of several reports describing the hydrologic studies and associated activities related to the Gila River Phreatophyte Project. The objectives of this project were to study the hydrologic changes resulting from the removal of phreatophytes and substitution of grasses. Numerous methods have been used for removing the phreatophytes, preventing reinfestation, and establishing the replacement vegetation. Varying degrees of success in controlling the phreatophytes have been achieved and varying effects on the hydrology of the site have been observed. This report describes the management of flood-plain vegetation during the period of the hydrologic study.

Advances in characterizing and monitoring land cover/use and associated ecosystem changes using remote sensing data

“…Between 1967 and 1971, the Bureau of Indian Affairs (BIA) cleared phreatophyte vegetation, defined as deep rooted plants that draw a large amount of the water they require from groundwater sources when precipitation is deficient (Naumburg et al, 2005), throughout the riparian floodplain along a 9-mile stretch of the San Carlos River and a 26-mile stretch (i.e., 15,800 acres) of the Gila River within the San Carlos Apache Reservation (Park et al, 1978). This project was referred to, shorthand, as the "Gila River Channel Improvements" project (Park et al, 1978). Clearing of the vegetation was completed using both mechanical-eradication methods (i.e., root plowing using a bulldozer, uprooting, mowing) and chemical-eradication (i.e., Silvex-a dioxin-based biological agent related to "Agent Orange") (Park et al, 1978).…”

Riparian vegetation response amid variable climate conditions across the Upper Gila River watershed: informing Tribal restoration priorities

“…Between 1967 and 1971, the Bureau of Indian Affairs (BIA) cleared phreatophyte vegetation, defined as deep rooted plants that draw a large amount of the water they require from groundwater sources when precipitation is deficient (Naumburg et al, 2005), throughout the riparian floodplain along a 9-mile stretch of the San Carlos River and a 26-mile stretch (i.e., 15,800 acres) of the Gila River within the San Carlos Apache Reservation (Park et al, 1978). This project was referred to, shorthand, as the "Gila River Channel Improvements" project (Park et al, 1978). Clearing of the vegetation was completed using both mechanical-eradication methods (i.e., root plowing using a bulldozer, uprooting, mowing) and chemical-eradication (i.e., Silvex-a dioxin-based biological agent related to "Agent Orange") (Park et al, 1978).…”

“…This project was referred to, shorthand, as the "Gila River Channel Improvements" project (Park et al, 1978). Clearing of the vegetation was completed using both mechanical-eradication methods (i.e., root plowing using a bulldozer, uprooting, mowing) and chemical-eradication (i.e., Silvex-a dioxin-based biological agent related to "Agent Orange") (Park et al, 1978). The clearing treatments primarily targeted phreatophyte species including tamarisk (Tamarix pentandra), which was the dominant vegetation species across the area, as well as mesquite (Prosopis) and cottonwood, which was also present in the floodplain (Park et al, 1978).…”

“…Clearing of the vegetation was completed using both mechanical-eradication methods (i.e., root plowing using a bulldozer, uprooting, mowing) and chemical-eradication (i.e., Silvex-a dioxin-based biological agent related to "Agent Orange") (Park et al, 1978). The clearing treatments primarily targeted phreatophyte species including tamarisk (Tamarix pentandra), which was the dominant vegetation species across the area, as well as mesquite (Prosopis) and cottonwood, which was also present in the floodplain (Park et al, 1978). In addition to the BIA clearing the vegetation, the USGS initiated the Gila River Phreatophyte Project (hereafter "Phreatophyte Project") to study the impacts of the clearing on hydrologic properties along the Gila River, including evapotranspiration and surface water flow (Culler et al, 1970;1982;Park et al, 1978).…”

“…The clearing treatments primarily targeted phreatophyte species including tamarisk (Tamarix pentandra), which was the dominant vegetation species across the area, as well as mesquite (Prosopis) and cottonwood, which was also present in the floodplain (Park et al, 1978). In addition to the BIA clearing the vegetation, the USGS initiated the Gila River Phreatophyte Project (hereafter "Phreatophyte Project") to study the impacts of the clearing on hydrologic properties along the Gila River, including evapotranspiration and surface water flow (Culler et al, 1970;1982;Park et al, 1978). Specific details were published within a set of USGS scientific reports published between 1970 and 1982 (see USGS Scientific Report 665, series A through P) (Culler et al, 1982).…”