CURLY LEAF PONDWEED (CLP)

This invasive plant species grows  rapidly to form a dense mat- like structure at the surface that chokes out desirable native plant species and restricts  recreational  boating and swimming. CLP dies at the end of June/early July and floats to shore causing disposal problems. The decaying CLP releases   2-5 pounds of phosphorus/acre, thus supporting severe algae blooms and low water clarity.

 

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ZEBRA MUSSELS

This invasive species rapidly  propagates  taking over lakes, killing other mollusks, and attaching to boat motors/bottoms, docks, lifts and any hard surface in or near the water. Frequent removal of the ZMs is required to maintain equipment functionality. The razor sharp shells of dead ZMs  eventually  cover the bottom and  prevent swimming/wadding without adequate foot protection. Because the thin dead shells can be blown by wind and storms, they can  collect  in heaps and piles, which could block not only the  shallow channels  connecting our three lakes  but also  entrances to  bays/channels.

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FLOWERING RUSH

Flowering rush is a perennial plant that grows one to four feet high along shores in shallow, slow-moving water. In deeper water, it can grow in a submerged form that does not produce flowers. It flowers in early summer through mid-fall. Flowers comprise of three pink petals and three sepals arranged in clusters or umbels (umbrella shaped) on a flower stalk. Flowers typically bloom in June through early fall. Small buds that form in the clusters of flowers can disperse and grow into new plants. Flowering rush is difficult to identify when not in flower, as it closely resembles many native, beneficial shoreland plants in Minnesota, such as the common bulrush.

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PHOSPHORUS CONTAMINATION FROM STORM WATER RUNOFF

Untreated storm water runoff (yards, streets, storm sewers, ditches, culverts, etc) deposits 2100 lbs of phosphorus /year into Forest Lake. This is NOT fertilizer phosphorus. The phosphorus comes  from decayed grass/leaves/vegetation  and sediment. It can come miles from the lake and needs to be controlled by shoreline plants, rain gardens, settling ponds and  4-5 other techniques depending on the situation/location where it flows into the lake.  This phosphorus and phosphorus build up supports algae blooms/low water clarity. One pound of phosphorus can support 500 lbs of algae! This is why Forest Lake is categorized as “eutrophic” and rated as “impaired” in about half of our open water months.

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EURASIAN MILFOIL

Eurasian watermilfoil is a perennial plant that flowers twice a year, usually in mid-June and late-July. It can grow up to 20 feet tall, but typically only grows three to nine feet tall. It creates canopy-like structures as it grows toward the water’s surface. It primarily establishes through vegetative fragmentation—a fragment can break off, settle in the sediment, grow roots, and establish a new plant. The plant dies back in the fall, but the root system can survive the winter and begin growing again in the spring.

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