Winter Weed Control: Virginia Creeper

The issue: Many noxious weeds start out as ornamental plants that escaped cultivation. Weed issues are cheaper to solve before they become a serious problem. Be proactive to keep potential plants from reaching the weedy stage.

Virginia Creeper (Parthenocissus quinquefolia) is a native of eastern North America. It is a climbing, woody, perennial vine that can be very nice in a home landscape that is large enough to handle its aggressive growth. It thrives in many soil types, as well as full shade and full sun. The dark green leaves are palmately compound with five leaflets to each leaf and have a deep red fall color. Adhesive discs at the end of the tendrils will allow it to climb almost any surface. The berries are deep-purple to black and a good food source for some birds.

The challenge comes from the seeds spread by birds and vines readily rooting as they creep along the ground. Unwanted seedlings pop up under roost sites. The berries are very bitter, so poisoning is not common, but they are toxic to humans. Virginia creeper is becoming a weed problem in northern Utah.

Integrated pest management options:

· Mechanical: Seedlings that are growing in an undesirable location can be easily pulled from moist soil.

· Cultural: Virginia creeper has the ability to climbing and grow over anything, so cultural practices are not effective.

· Biological: Grazing or browsing by some livestock will reduce the growth rate.

· Chemical: Cut-stump application of glyphosate or triclopyr is quite effective in killing stumps of older vines (see previous posts on the techniques). Be sure the target weed and crop or landscape situations are listed on the product label. Always read and follow herbicide label directions.

Combine them: Combine different IPM options to help improve the effectiveness of your efforts.

For more information, contact Ron Patterson, University of Idaho Extension horticulture/agriculture educator in Bonneville County.