Jewelweed

Jewelweed is a native plant that is now in bloom. You can find jewelweed growing in moist areas that have a moderate amount of shade, such as an open forest or a forest edge. It belongs to the impatiens family, of which there are nearly 850 species worldwide, and gets its name for the silvery sheen found on leaves when they are dipped in water or covered with dew.

Jewelweed is a summer annual that grows 2 to 5 feet tall and has a rather fragile stem. The two to three flowers per stalk are usually orange-red to yellow. Later in the summer, the plant produces seeds in pods that will explode out of the pods if pinched with your fingers. Hummingbirds as well as swallowtail butterflies and honeybees readily feed on this plant's nectar.

The sap contains parinaric acid, which has anti-inflammatory activity and is a fungicide. Jewelweed has been used as a home remedy for bee stings, insect bites, poison ivy and athlete's foot.

Fungal disease of stilt grass

Japanese stilt grass (Microstegium vimineum) has become a serious invader of local landscapes, spreading rapidly across forests and grassland communities. This invasive plant offers little in the way of food or cover for wildlife, and it can diminish the fertility of soils by secreting allopathic chemicals that kill beneficial soil microorganisms.

Many believe that stilt grass has become one of the worst invasive plants found in our region. This grim reality may change now that a naturally occurring fungus known as Bipolaris has been shown to kill the stilt grass.

The dieback of stilt grass was first observed in Calhoun County, W.Va., in 2008, and during 2009 other outbreaks were observed in other sections of West Virginia, Maryland and Indiana. Researchers at Indiana University have been studying this development, and a recent article in the Journal of Plant Disease details preliminary observations.

So far, researchers do not know how the disease got established, how it spreads or whether or not it will affect other plants. The disease first shows up in early June, when dark lesions appear on the stilt grass leaf. A few weeks later, the plants turn brown, dry up and perish. This disease offers some hope that natural controls will reduce the impact of this aggressive invasive plant.

Nature Notes for 7/10/2011