Mustard plants growing wild and wilder

There are two members of the mustard family currently blooming in Frederick County: the wild mustard (Synapis arvensis) and the garlic mustard (Alliaria petiolata).

The difference between these plants is that wild mustard is found growing in open fields and has a yellow bloom, while garlic mustard is usually found growing in and around forests and has a white flower. Both are native to Europe and Western Asia and were brought to this country in the 1800s as a potential food source.

Garlic mustard grows best in shady conditions and does not tolerate acid soils. It has become a major threat to herbaceous plant life in the area's more productive lower-sloped and bottomland forests. Garlic mustard is a biennial that produces large amounts of seed that can stay viable in the soil for five years or more. It grows quickly in the spring and can out-compete many native herbaceous plants.

Garlic mustard also produces allopathic chemicals that can poison nearby plants and causes the demise of beneficial mycorrhizal fungi; this degrades the soil, creating conditions favorable for this and other plants that can grow on poor sites. Garlic mustard is also distasteful to deer and other animals, so they leave this opportunistic plant alone.

With all these weapons at its disposal, it's easy to see how garlic mustard can overrun a forest once it becomes established. It can be controlled by pulling it out of the ground or by cutting it down. It is important to conduct these control practices before the plant goes to seed; any control program should be conducted for three to five years so as to target seeds that might be laying dormant.

Pull garlic mustard when the soil is most so all of the plant is removed, because if roots are left behind they can develop into a new plant. Garlic mustard can also be controlled by herbicides, but a long-term strategy is also necessary for control due to the viability of seeds.

Wild mustard is a non-native annual plant that is usually found in disturbed agricultural fields. Sometimes a field can be completely covered with this yellow-flowering plant. The seed of the wild mustard can remain viable for up to 60 years. The wild mustard can be a pest of agriculture but it rarely overruns native meadows, old fields or forests.

Courtesy Photo

In spring, we start seeing the reproductive phase of the carpenter ant with wings. Both males and females develop wings for seeking mates.

Flying carpenter ants take flight

One of the most common species of ants in Maryland, and also one of the largest in size, is the black carpenter ant (Camponotus pennsylvanicus).

In spring, we start seeing the reproductive phase of the carpenter ant with wings. Both males and females develop wings for seeking mates. After mating, the wings are dropped and the ants try to find damp wood locations to build nests. Unlike termites, which eat wood, carpenter ants excavate galleries for their nests, preferring wood with high moisture content.

Dead or rotting trees are most often the locations for carpenter ant nests. In houses, damp areas around windows, roof eaves and porches can become carpenter ant habitat.

Seeing winged carpenter ants in and around the home does not necessarily indicate there is a nest in the house. Most winged ants seeking mates die before establishing a nest.

Better indicators of a nest in the house are when carpenter ants without wings are seen in the home during early spring, late fall and winter.

Nature Notes for 5/15/2011