Nature Note – Pollen

A yellow scum often appears along the shores of Lake Champlain from late spring through early summer. Though the scum has the texture and consistency of an algae bloom it is actually pollen. While the pollen may be unsightly, its presence means there are many pine trees in the vicinity of the lake, and thus indicates a degree of health in the watershed.  

The pollen on the lake’s surface represents wasted effort on the part of the pine trees. Pollen is the means by which plants convey genetic material from a male plant or part of a plant to a female. Pine trees are monoecious, which means the male and female parts can be found on the same tree. To avoid self-fertilization, male cones develop on a given tree one to two weeks before the female cones. The pine pollen is then wind dispersed, which is not a very efficient means of getting from plant to plant. Whatever ends up in the lake did not make it to a female tree.

On occasion algae blooms and pollen on the lake might coincide, but generally algae blooms later in the season after the water has warmed more and the pines have finished producing pollen for the year. Over time the pollen will become water logged and sink to the bottom.