Introduced perennial from Europe. Reproduces by seed and underground rootstocks. The creeping rootstocks give rise to roots and shoots every few inches. Plants are bright green, 2/3 to 2 feet high, in bunches from wide-spreading roots, with milky juice. Stems are branched at top, very stiff and woody when mature. Leaves oblong, scattered, except the whorl of lanceolate or oblanceolate bractlike yellow leaves at the base of the umbel. Flowers very small, greenish-yellow or with brownish spots, have a dark line down one side and a yellowish appendage at the point of attachment, seeds are borne in a three-lobed capsule (3 seeds per pod). Flowers May to September and seeds June to August.
Prevention of Spread of Leafy Spurge
The occurrence of new infestations of leafy spurge can be reduced by planting weed free seed, feeding livestock materials free of leafy spurge seed and cleaning equipment before leaving infested fields. Close attention should be placed on any feed or seed materials imported from the northern and north western states. Quick identification and destruction of leafy spurge plants is essential to prevent its spread.
Leafy Spurge Control Practices
Control of leafy spurge shall mean preventing production of viable seed and destroying the plant's ability to reproduce by vegetative means.
Cultural Control Practices
Cultivate every two weeks from the beginning of spring growth to August 1 and every three weeks thereafter until fall. Intensive cultivation between harvest and sowing of winter wheat or rye will reduce the stand of leafy spurge. Leafy spurge roots are easily transplanted. Clean the equipment before moving from the infested area to prevent spreading the infestation.
Herbicides Approved for Controlling Leafy Spurge
The following herbicides may be used for cost-share with landowners. Other products labeled and registered for use on this noxious weed in Kansas may be used in accordance with label directions but are not available for cost-share. Be sure to follow all label directions and precautions. For additional information consult the current KSU publication of AChemical Weed Control for Field Crops, Pastures, Rangeland, and Noncropland.
- 2,4-D LV Ester. Apply during the true flowering stage in the spring and again in the fall to the regrowth. Follow label directions and precautions.
- Picloram (Tordon 22k). Restricted use pesticide. Follow label directions and precautions.
- Picloram + 2,4-D (Tordon + 2,4-D). Restricted use pesticide. Apply Picloram + 2,4-D during the true flowering stage in the spring. Follow label directions and precautions.
- Imazapic (Plateau) Follow label directions and precautions.
- Imazapic + Glyphosate (Journey) Apply in the fall until freeze. Follow label directions and precautions.
- Diflufenzopyr + Dicamba + Picloram (Overdrive + Tordon 22k). Restricted use pesticide. Follow label directions and precautions.
- Glyphosate (Roundup). Follow label directions and precautions.
Biological Control Practices
There are no biological control practices approved for leafy spurge at this time. A potential nationwide leafy spurge biological control program is being considered by the USDA. Kansas will consider participation is such a program if it is implemented.