Printable PDF Smooth Bedstraw Factsheet

Smooth Bedstraw (Galium mollugo)*

Smooth bedstraw is a weed that is rapidly becoming a problem in local pastures and hay fields. It is a non native plant that under less than ideal growing conditions and cutting or grazing management can quickly crowd out native crop plants. Below are recommendations for combatting this pest. New research is underway and we may bring better strategies in the future.

Smooth bedstraw is a creeping perennial. It also is a prolific seed producer and can be spread quickly by animals and equipment. It will flower in June, and if mowed, again in August.

Preventative control where weed pressure is light is best accomplished by competition of the crop plants themselves. Hay fields should be limed and fertilized properly. Cutting should be often enough to prevent Bedstraw seed production, but with long enough interval that grass will grow larger than Bedstraw and be competitive. In pastures, animals may graze Smooth Bedstraw if is young and tender, but once Bedstraw matures, it will be less palatable. Bedstraw contains a number of toxic compounds.

Grazing or mowing practices can have a great impact on forage plant growth and vigor. Rotational grazing that allows the forage plants to recover is the best. Try to have enough pasture divisions so that your animals stay in a single paddock only a few days. Paddocks need enough time for pasture plants to re-grow (2 to 3 weeks). Mowing the hayfield or pasture before the bedstraw goes to seed (just as it starts blooming or earlier), will help reduce seed production.

Mowing alone will not control Smooth Bedstraw because it will continue to regrow and spread via its rhizomes or underground stems. Fertilization, particularly with nitrogen will help the crop plant crowd out the Bedstraw. For a pasture, fertilize a couple times a year (late spring and late summer/early fall) at about 50 lbs of actual N per acre at each application. Soil test for any lime, phosphorus and potassium needs and if necessary substitute one of the N applications with a blended fertilizer that has N, P and K in it. Lime could go on anytime. Overseed any thin and spotty areas of pastures each year. Early fall is a good time to do this. For example, a mixture of perennial ryegrass, Kentucky bluegrass and white clover.

Once Bedstraw is firmly established control is best accomplished by tilling and reseeding. Herbicide is another choice although Bedstraw has shown to be tolerant of some herbicides and may require high labeled rates of application.

*Adapted from Sid Bosworth, UVM Extension and Stefan Seiter UNH Extension

Picture: Flora Danica Online http://www.pictures.dnlb.dk/