All living aquatic algae are actually primitive plants! The main difference from other aquatic plants is that algae are defined as having no stems, leaves, or having no real root structures as they commonly exist. There are thousands of species but typically they are found either floating on or near the surface or actually attached to other plants, bottom sediments or debris and even to other real plants! While scientifically speaking there is upwards of 10,000 varieties of aquatic algae, they can all be separated in three fundamental categories: attached-erect algae, microscopic algae and filamentous algae. Most golf course pond owners we know can only separate all the species of algae into two different groups: The algae the ruins their golf course pond and the other stuff they don't care about!
The microscopic algae that are sometimes referred to as phytoplankton are free-floating, extremely tiny creatures that give golf course pond water a greenish tinge, or, in the case of a full out bloom, a dark opaque green color. Naturally, a balanced golf course pond is alive and so the existence of the proper levels of such algae is beneficial as they can be the primary dissolved oxygen factories that produce life giving oxygen for other organisms and fish in the pond. Sometimes during warm summer days, especially in midsummer when heat and windless days abound, major algae blooms can occur that rise to the surface and can appear as green or or reddish or even yellow scum. When there is a rapid kill-off of these microscopic algae caused by abrupt changes in water temperature for example, the ensuing death can lead to severe depletion of dissolved oxygen levels and cause severe damage or elimination of other species including fish. Keep a watchful eye on the golf course pond and be prepared to react whenever the lovely pale greenish water tinge, the natural healthy state, suddenly changes into a bright pea-soup! This is a warning sign!
In most healthy golf ponds you should be able to see a fairly bright object clearly to a depth of at least two feet and if a secchi-disc or similar homemade device is not visible before a 24 inch depth is reached it could signify that the golf course pond is suffering from or preparing for an algae event. This is when seeking advice on treatments is mandatory, and, as we stated above, is likely to start with treatments of bacteria, dyes and of course the all-important proper aeration device.
What are known as attached-erect algae are not as big nor as common a problem in golf ponds in Canada or the United States but nonetheless, when blooms of these attached-erect species occur it definitely makes life miserable for swimmers and anyone interested in fishing without losing their lures on the thick mats of submerged weeds. This algae is sometimes referred to as muskgrass, stonewort or sometimes even golf course pond weed, although that is actually a misnomer because even though they do resemble an advanced plant with veritable leaf-like structures spaced plant like on a common stem structure. Before starting any treatment targeting these algae it should be positively identified especially if you are considering a chemical treatment. Again, reducing nutrients and increasing circulation while manually removing the algae is the most natural approach to control.
The hair like, filamentous type of aquatic golf course pond algae is the ultimate headache causing nuisance for golf course pond owners in almost all areas of the country as this type of algae is extremely tolerant to cool water temperatures and blooms can begin in early Spring, just when the pond has cleared of ice and the golf course pond owner starts to dream of swimming in crystal clear waters so when this messy muck floats to the surface the effect can be absolutely discouraging. The blooms of filamentous algae are fundamentally born in shallow water areas when waters are clear and sunlight can penetrate and reach the nutrient rich soil of the golf course pond bottom.
The conditions of light and food cause cells to rapidly grow and multiply and these cells actually clump together in long strands that resemble green hair, or witch hair as some will refer to it. These hairy masses also grow in almost furry clumps on the bottom of the golf course pond and often break apart and drift to the surface of the water in dense gelatinous mats. These floating algae blooms are very unattractive and can be smelly; not to mention that a sudden die-off of the masses of algae can lead to serious issues within the golf course pond due to the sudden drop in oxygen levels related to the death of the algae.