Almost all pollens that are allergens are from anemophilous species. The airborne spores from mushrooms reach levels comparable to those of mold and pollens. The northern shores contain mainly fossil plants, pollens and spores. Its pollens are not poisonous for honey bees. Anemophilous pollens may also be inadvertently captured by bees' electrostatic field. The pollens are spherical with approximately 188 microns diameter. The species consumes fruit flowers and pollens of around 187 plant species. Even more significant is the assemblage of fossil pollens and other microflora in the shale. These pollens have three or more pores set in furrows called colpi. The pollens are oval in shape, approximately 40 microns in length. The study of pollens which persist in soil for many years is called palynology. Here, it is expressed in the strobili, an organ that produces pollens or ovules. The pollens are spherical in shape. This link is also supported by a similar, though less prominent, trend in "Rhizophora" pollens. Pollens are elongated, approximately 35x18 microns in size.