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.
Used in geology, hydrogeology, soil science, and building science, the porosity of a porous medium (such as rock or sediment) describes the fraction of void space in the material, where the void may contain, for example, air or water. It is defined by the ratio :orosity is the ratio of pore volume to its total volume. Porosity is controlled by: rock type, pore distribution, cementation, diagenetic history and composition.