Liverworts
Wednesday, 20 December 2006 09:47
Liverworts (Marchantia polymorpha) are branching, ribbon-like plants lacking distinct roots, stems and leaves. They reproduce by spores and vegetatively. Stalked, umbrella-like structures release spores. Small, bud-like branches produced in cup-like structures on the surface of the plant also help spread liverworts from pot to pot by water droplets during irrigation. Liverworts thrive in conditions of high fertility, moisture and humidity.
Inspect incoming plants for signs of liverworts and isolate infected plants. If the growing media stays moist, small infestations of liverwort can quickly spread through an entire greenhouse. Clean and disinfect empty greenhouses to remove spores. Store growing media properly to prevent contamination from the spores.
Avoid overwatering crops and water according to plant need. Use of coarse textured mulch helps reduce surface moisture levels. Topdressing slow release fertilizers contributes to increased fertility levels on the media surface and to the growth of liverworts. Proper plant spacing helps to reduce humidity levels. Liverworts lack true roots, so allowing the media to dry between watering, helps reduce their vigor.
Sodium carbonate peroxyhydrate (TerraCyte®) is labeled for the prevention and control of algae, moss, and liverworts. Terracyte® is water activated. Several precautions are noted on the TerraCyte®label. First test a small section of ornamental plants at labeled rates for potential phytotoxicity before large-scale use. Phytotoxicity may occur on sensitive crops. Thoroughly rinse granules of foliage to prevent contact burn. Repeat applications can also raise soil pH to levels that can adversely affect plant growth. TerraCyte® is also incompatible with metal-based fungicides and fertilizers.
Leanne Pundt
Extension Educator
University of Connecticut
