MSU Extension Floriculture & Greenhouse Crop Production

Container-grown ornamental plants need to be weed-free or there is the risk of significantly reduced growth, aesthetics and the market value of nursery crops (Fretz, 1972). Yellow woodsorrel (Oxalis stricta), also known as oxalis, is one of the most common broadleaves weed species in container nurseries and greenhouses in Michigan. It is an annual weed species in cool climates, such as the northern United States, and a perennial weed in warmer regions. Oxalis is native to North America and is widely distributed throughout the world including the eastern and central United States, Europe, Africa, Asia, Japan and New Zealand (Lollar and Marble, 2015).

Oxalis is difficult to control because it can spread by rhizomes, stolons and by seeds, which have no dormancy requirement. According to Neal and Derr, 2005, oxalis populations can negatively affect the growth rates of ornamental crops. This bulletin will aid in oxalis identification, understanding its biology and developing management strategies.