We are in the business of making products to help you manage your aquatic weed and algae growth…so why on earth would we suggest keeping chara in your pond? There is actually a good explanation for why keeping some of this growth can be beneficial for your body of water.
Chara (also known as muskgrass, stonewort, or skunkweed) is frequently misidentified as a weed, but it is actually a type of algae. With its stem and plant structure resembling a weed, it is understandable how there could be some confusion. It grows in big billowing puffs on the pond floor and can breach the surface of the water once it becomes thick enough. It has a crunchy texture and a musky odor.
At Sanco, we typically view green in a pond as "bad" and then we offer suggestions to treat the growth accordingly. Chara can be tricky to control due to the fact that it re-establishes from spores and fragments. It is a bit different than your typical algae, as it is a filter algae. This means that the presence of chara in your pond creates very clean and clear water. This is why we highly advise keeping at least a fair population to ensure your pond water remains this way. Another benefit of chara is that it takes up space that might otherwise be taken over by other problem weeds or growth. The thickness of chara makes it a great cover for any fish in your pond. Many species of ducks and other types of wildlife sometimes use chara or even decomposed chara as a food source.
Though having some chara is good, having excessive chara can be a understandably unattractive in your pond. The most effective pond algae treatment is with liquid copper sulfate, like Crystal Plex. Granular copper sulfate will not treat chara. If you wait until it's too late in the season, usually anytime after July, algae can and will become calcified and treatments will be ineffective. Thick groupings of chara can also be removed with a specialized aquatic weed cutter. This method can be time consuming and is a more hands-on approach than just spraying chemical. It is only recommended to use a weed cutter on chara as long as you have small patches of growth. Weed cutters are quite effective as long as you have good aim!