Biological Control of Small Soapweed (Yucca glauca Nutt)

1997 Annual Report for FNC97-180

Project Type: Farmer/Rancher
Funds awarded in 1997: $4,515.00
Projected End Date: 12/31/1998
Region: North Central
State: Kansas
Project Coordinator:

Biological Control of Small Soapweed (Yucca glauca Nutt)


Chemical weed control on western range sites, although effective, is costly, time-consuming and may adversely affect some of the desirable native vegetation.

Objectives: To demonstrate and confirm the effectiveness of Waygu crossbred cattle as a cost-effective, low-management biocontrol of small soapweed. A yucca-infested pasture was slected for a demonstration site to compare Waygu crossbred cattle, British crossbreeds, chemical treatment and a control site. Yucca stand counts were taken on all sites prior to grazing season on May 1, and final stand counts were taken on completion of grazing November 1.

Results: Sites where British-cross cattle grazed exhibited some grazing of flowers but all seed stalks remained and all yucca appeared healthy. Sites where Waygu-cross cattle grazed exhibited some healthy yucca; however, few seed stalks remained and many plants were grazed with leaves truning brown. The chemically treated yucca showed damage and yellowing of leaves on all plants, while plants in the control plots were healthy.