Cabbage+Moths

Yellow Cabbage Moth // Pieris rapae //

Fig 1. Yellow cabbage moth sucking nectar from an aster.

__Kingdom__: Anamalia __Phylum__: Arthropoda __Class__: Insecta __Order__: Lepidoptera __Family__: Pieridae __Genus__: //Pieris// __Species__: //P. rapae//

How to Identify: -Upper-side of wins white or yellow -Forewing has a black tip -Female has two black spots, male only has one. -Underside of wing and forewing apex can be yellow- green or gray-green. -Wing span: 1.75-2.25 inches (4.5-5.8 cm)

Life Cycle: Males patrol for females and they mate in the spring. The females lay single yellow, long and ridged eggs on the underside of host leaves. Depending on temperature, it can take any where from 3 to 7 days to hatch from the egg. The hatched larvae feed on the upper surface of the leaf for about two weeks until they grow to full length. The larvae are green with faint yellow stripes running longitudinally, as pictured below. Fig 2. Larvae eating leaves they were hatched on. The bottom picture shows the larvae pupate in the green chrysalis, which they attach to any garden or farm object. It takes from one to two weeks to compete the pupal stage.

Fig 3. Pupating chrysalis. Each season there are three to five overlapping generations and in the pupal stage of the last generation overwintering occurs.

Habitat : -Gardens   -Roadsides   -Cities   -Suburbs   -Weedy areas

Interesting Facts:

This is an invasive species. It is originally from Europe and was imported to Canada in the mid-1800's. Since then it has spread all over the continent and become a huge pest for farmers and gardeners. Since the eggs are laid on leaves, as soon as they hatch as caterpillars they begin to eat the plant, and leave tons of holes. They typically enjoy eating plants from the mustard and capper family, including plants such as turnip, radish, mustard and nasturtiums. The moths lay their eggs on such plants to supply their larvae for food as soon as they hatch. The most effective way to control these pests are by using a variety of different parasitic wasps in places that are abundant with cabbage moths. The wasps feed either the egg or the larvae. This is beneficial because if there is no egg, there will never be larvae hatched and that is the most damaging stage of the cabbage moth.

A. Howard

Interesting Links

Identifying Early Stages of Moth Encyclopedia Entry How to manage these pests

References: Literature:

1. Writer, S. (2013, November 5). Cabbage white butterfly. Retrieved from http://www.insectidentification.org/insect-description.asp?identification=Cabbage-White-Butterfly

2. Michael, F. (2013, December 3). Organic strategies for caterpillar control. Green Harvest Organic Garden Supplies, Retrieved from http://www.greenharvest.com.au/PestControlOrganic/Information/CaterpillarControl.html

3. Hutchison, W. D., Bolin, P. C., & Hines, R. L. (2013).Importated cabbageworm. Informally published manuscript, University of Minnisota Department of Entomology, Retrieved from http://www.vegedge.umn.edu/vegpest/colecrop/cabbworm.htm

4. Chapman, M. (2009). Butterflies and moths of north america. Retrieved from http://www.butterfliesandmoths.org/species/Pieris-rapae

Images:

1. Camer, A. (Photographer). (2008, June 3). Clouded Yellow, Cabbage White, Blues & Cloak [Web Graphic]. Retrieved from http://butterflies-seen.blogspot.com/2008/06/clouded-yellow-cabbage-white-blues.html

2. Wikipedia