Mullein growth patterns
Iesha Brooks and Grace Harsha
Ecology class, BIO 342, Biology Department, DePauw University
Fall semester 2014
Mullein is biennial non-native plant introduced from Europe. The plant forms a rosette during the first year. During the second year, it forms a tall flowering stalk. The plant has a restricted dispersal pattern. Thousands of seeds are dispersed over a few yards. Seeds have a slim chance of survival. Most seeds become dormant and germinate when conditions are better, usually after a disturbance. The goal of our study was to investigate why mullein grows and survives in some areas and doesn’t grow in other areas.
We hypothesized that mullein would grow in shaded areas of mixed gravel and soil next to trails in the DePauw Nature Park.
We conducted our study at 12 locations along the Quarry Trail and Prindle Trail in the DePauw Nature Park. We counted the number of plants, estimated the health of the plants on a scale of 1 to 5 (1 = excellent health, 5 = very poor health), collected soil samples, separated the soil samples using sieves to quantify soil texture, and used a densiometer to estimate canopy cover.
The number of mullein plants varied among the locations. Juvenile plants were more abundant and healthier than adult plants. Mullein was most common in areas with medium soil texture.