Weeds of Container Nurseries in the United States

Liverwort is a primitive, moss-like plant that form leaf-like mats on the soil surface. When dry, these mats repel water, causing pots to dry. Plants reproduce by wind-dispersed spores and (more commonly) by gemmae produced in cup-like structures. Gemmae are splashed out of the cups by rain or irrigation. Liverwort prefers moist, cool conditions, and occur primarily in crops with frequent irrigation, such as propagation areas and herbaceous perennials. Liverwort is very difficult to control. Inspect purchased liners and eradicate new infestations before they can spread. Liverwort has been suppressed by some preemergence herbicides, mulches, and nonselective contact herbicides. However, procedures and products effective in one nursery do not necessarily work elsewhere. Persistent infestations will require frequent hand weeding and changes in cultural practices to achieve acceptable suppression.