ID and Burndown Options for Wild Garlic, Grape Hyacinch and Star-of-Bethlehem.

DR. LARRY STECKEL

 JACKSON, TENNESSEE

 This spring some fields seem to be infested more heavily with wild garlic, grape hyacinth and in a few cases, star-of-Bethlehem. These three weeds, in the Lily family, are often mistaken for each other as they all derive from bulbs and are low-growing perennials.

 In particular, grape hyacinth and wild garlic look very similar as they both have round hollow leaves that end in a point. The best way to tell them apart, before grape hyacinth flowers, is that wild garlic has a distinct odor when cut or crushed and grape hyacinth does not. Once grape hyacinth flowers they are easy to tell apart as that plant has distinct blue flowers that somewhat resemble a grape (Picture 2).

Star-of-Bethlehem has flattened leaves with a prominent mid-rib. That leaf architecture really tells it apart from the other two weeds. Its flowers are white.

 From a burndown before planting perspective, if the infestation is low then the often used glyphosate + dicamba or glyphosate + Verdict burndown will do a good enough job. Please note that these options provide only about 50% suppression. However, in fields with heavy pressure these weeds can make uniform stand establishment more of a challenge and a more effective option is needed. The herbicides with the best activity on these Lily family weeds are Firstshot, 2,4-D, and Elevore.

 Firstshot has good activity on this Lily family of weeds. The use rate is 0.6 to 0.8 oz/A. This herbicide is very effective on wild garlic and from observations through the years has shown some decent activity on grape hyacinth and star-of-Bethlehem. The plant back to soybeans is 7 days and to cotton, corn and grain sorghum is 14 days.

 The two auxin herbicides that are pretty effective on these weeds are 2,4-D and Elevore. The 2,4-D is a quart rate of either the ester or amine formulations. I do not have as much experience with Elevore on grape hyacinth or star-of-Bethlehem but on wild garlic our research would indicate very good activity. Elevore is in better supply this year and should be applied at the rate of 1 oz/A. The plant back to corn is 3 days (label specifies planting depth at least 1.5”) while soybean and grain sorghum is 14 days and cotton is 30 days. ∆

DR. LARRY STECKEL: University of Tennessee