Star of Bethlehem control has been difficult in the past. We now have some new herbicide tools for this problem weed. The following is an article on the subject.
STAR-OF-BETHLEHEM is a major perennial weed in turfgrass and landscapes. It is a bulbous perennial with fleshy grass-like leaves that grow up to a foot long with a whitish grooved midrib. From April to June, the plant produces bright white flowers with 6 oblong petals that have a distinctive green stripe underneath.
Star-of-Bethlehem generally dies back to underground bulbs during summer following seed dispersal. Ovate bulbs of Star-of-Bethlehem grow in clumps in the soil. Reproduction by seed is minimal but plants may germinate from dormant seed during spring months.
Controlling Star-of-Bethlehem is difficult since the plant can regenerate shoot tissue from vegetative structures following herbicide injury. Most pre- and post-emergence herbicides, including some non-selective materials, do not effectively control Star-of-Bethlehem. Glyphosate-containing products (such as Roundup®) often provide inconsistent and erratic levels of control and are not recommended. Multiple applications of diquat (Reward®) at 3 week intervals may effectively control Star-of-Bethlehem but may severely injure surrounding grasses and plants.
Recently, Research conducted at Virginia Tech University demonstrated that carfentrazone (Quicksilver T&O®) has substantial herbicidal activity on Star-of-Bethlehem and is safe on all cool-season turfgrasses. Applying Quicksilver T&O at 4 oz/acre once or 2 oz/acre twice at 3 week intervals gave 88 to 95% Star-of-Bethlehem control in tall fescue. Unfortunately, single applications of Quicksilver T&O® can not currently exceed 2.1 oz/A. In addition, Quicksilver T&O® is not systemic and Star-of-Bethlehem may continue to be problematic in successive growing seasons.
Reprinted from an article by Dr Steve Hart, Extension Ornamental and Turf Weed Specialist, Rutgers University.