After the summer of the second year of growth the plant produces seeds. One individual can produce 100,000 to 180,000 seeds. These seeds are released in close proximity to the plant and can remain viable for over 100 years. The invasive common mullein prefers dry and sandy soils, but is adaptable to many soil types.
primary porosity. (geology). Natural porosity in petroleum reservoir sands or rocks. 1  Facebook. 2  Twitter.rimary porosity. (geology). Natural porosity in petroleum reservoir sands or rocks. 1  Facebook. 2  Twitter.
Refers to the fraction of the total volume in which fluids or gases are present but in which fluid flow can not effectively take place and includes the closed pores. Understanding the morphology of the porosity is thus very important for groundwater and petroleum flow.