Oak trees also drop prodigious quantities of pollen. It can literally cover walkways and patios. It also gets into pools and turns the water a yellow green color.
Unfortunately, chemicals won’t affect it. It’s up to the pool’s filter to take out the pollen. Oak pollen season runs from late February to late April depending on the weather.
If pollen is suspected, filtering 24 hours a day will make the water clear again. Pollen will frequently settle onto the sides and bottom of the pool, especially where the pool sweep doesn’t reach. While the filter is running, brush the pool to unsettle the pollen so that it is suspended, giving the filter a chance to remove it.
Every year we get a lot of calls about algae in pools between February and April, and it turns out to be pollen which chemicals can’t control.
If left on the pool surface for a long time, the pollen can stain the plaster, and give it a dirty, yellow green look. It is best to keep filters and pool sweeps running the recommended number of hours a day during the pollen season.