Current Topics of Importance
Aquariums & Aquatic Invasive Species (AIS) Aquatic Invasive Plants sold for aquariums Scientific name & Synonyms For more information see the Wisconsin Department of Natural Resources website at http://www.dnr.state.wi.us/invasives/, or contact Audrey Greene, Walworth County Land Use & Resource Management at 262-741-7902 or agreen@co.walworth.wi.us.
As fall winds down and winters cold temperatures freeze the lake, those of us that love the water look for other ways to experience the pleasure of it. Many people find that the underwater world of aquariums do provide the relaxation and beauty they crave.
Pet stores and internet sources make setting up and populating an aquarium easy and fun, but aquarium enthusiasts need to be aware that Chapter NR 40, Wisconsin’s Invasive Species Identification, Classification and Prevention law has resulted in the regulation of some popular, but highly invasive, aquarium plants. Several of these prohibited and restricted plants are sold through the internet and out of state sources. They are often promoted as species that will beautify and oxygenate your tank, and while they may indeed be beautiful, they could cause huge problems for Wisconsin waterways. Below is a list of popular aquarium plants that are prohibited or restricted. Prohibited species may not be transported, possessed, transferred or introduced in Wisconsin. Restricted species may not be transported, transferred, or introduced in Wisconsin.
There are many aquarium plants that are not listed as AIS in Wisconsin so there will be no shortage of attractive plants for aquatic gardeners to enjoy. Regardless of whether or not an aquarium species is regulated in Wisconsin, never dump any plants, fish or animals into any lake, pond or stream. Besides the fact that it is illegal and the fines are quite large, they could do immense harm to our waterways.
To further protect Wisconsin from AIS, verify the scientific names of any aquatic plants purchased and inspect all shipments/purchases to ensure that the plant ordered is indeed the plant received and that there are no ‘hitchhikers’ included. Dispose of unwanted aquarium species responsibly. Check with your retailer for possible returns or bag and throw in the trash.
Common Name(s)
Notes
Cabomba caroliniana
Fanwort, Carolina fanwort
Prohibited; submersed perennial; native to southeastern United States; often confused with water milfoils and water buttercup
Crassula helmsii
Australian stonecrop, New Zealand pygmyweed
Prohibited; sold as an oxygenator for ponds and aquariums
Egeria densa
Brazilian waterweed; Brazilian elodea
Prohibited; sold as an oxygenator for ponds and aquarium; native to South America; may be confused with Hydrilla verticillata and Elodea nuttallii
Hydrilla verticillata
Hydrilla; water thyme; Florida elodea
Prohibited; submersed perennial; native to Asia; introduced to Florida in 1958 as an aquarium plant; may be confused with Elodea canadensis, Egeria densa
Hydrocharis morsus-ranae
European Frog-bit
Prohibited; Free-floating perennial; can be confused with water lily and Limnobium spongia
Lagarosiphon major
Oxygen weed; African elodea, African waterweed
Prohibited; submersed perennial; may be confused with Elodea Canadensis and Elodea nuttallii
Myriophyllum aquaticum
Parrot feather
Prohibited; submersed perennial; may be confused with other milfoils
Myriophyllum spicatum
Eurasian water milfoil
Restricted; submersed perennial; may be confused with other milfoils
Najas minor
Brittle, lesser, bushy, slender, spiny and minor naiad; waternymph
Prohibited; submersed annual, reproduces by seed and fragmentation; easily confused with native Najas spp.
Nymphoides peltata
Yellow floating heart
Prohibited; bottom rooted perennial with floating leaves;
Potamogeton
Curly-leaf pondweed
Restricted; submersed perennial; introduced as an aquarium plant
Trapa natans
Water chestnut
Prohibited; annual floating leaf emergent
Blue-Green Algae In Wisconsin Waters
dnr.wi.gov/lakes/bluegreenalgae
2011 AQUATIC PLANT MANAGEMENT
Delavan Lake Sanitary District (DLSD) follows the recommended Aquatic Plant Management Plan prepared by Southeastern Wisconsin Regional Planning Commission. This plan recommends mechanical harvesting be used as the primary means to control aquatic plants. Harvesting is limited to cutting access lanes until June 15, and all harvesting is limited to harvesting of non-native aquatic plants, such as Eurasian Water Milfoil. Chemical treatment applications are limited to shallow water areas near shore; are limited to controlling nuisance growth or exotic species; and are limited for nuisance algae. A survey of aquatic plants is conducted each summer to help identify the plant species, location, and density of plants found in Delavan Lake (see below). This past summer, 15 different species of aquatic plants were identified and plants were found in lake depths up to 17 feet.
LAKE SPRAYING PLANS
We have again been granted a permit from the Department of Natural Resources for chemical treatments on Delavan Lake. A copy of the permit is available by contacting the District office.
Chemical spraying for nuisance aquatic plants is planned as follows:
Inlet Area - Due to The Town of Delavan's dredging activity in the Inlet, spraying will be done on an "as needed" basis.
Outlet Area -The first treatment will be in early May. Additional treatments as needed. The treatment area will be around the piers and up to 150 feet from shore.
Southwest Bay - This area goes from South Shore Manor west to the Island. Treatment is planned for early June. The treatment area will be around the piers and up to 150 feet from shore.
Northwest Bay - This area goes from Chicago Club west to the Island. Treatment is planned for early June. The treatment area will be around the piers and up to 150 feet from shore.
North Shore - This area extends from the Yacht Club to Assembly Park. Treatment is planned for early June. The treatment area will be around the piers and up to 150 feet from shore.
We again plan to treat the entire developed shoreline for algae control. The initial treatment is planned for a week to 10 days before the July 4th holiday. Additional treatments may occur in mid-July and mid-August if conditions warrant.
All planned chemical treatments are subject to lake and weather conditions as well as Department of Natural Resources approval.
MECHANICAL HARVESTING
Our plans for mechanical harvesting remain much the same as past years. We intend to launch our harvesting equipment the week of May 16th and begin the initial harvesting of plants in the access channels at that time. After June 15th we will harvest all areas of the lake as conditions warrant. The harvesters will only operate in the chemically treated area to supplement the chemical treatments.
SHORELINE PICK UP FOR 2012
DLSD will again pick up aquatic plants left at the end of piers. Property owners are required to call 728-4100 before the scheduled pick up dates and request a pick up. Requests may be left in the DLSD general voicemail box. Please leave your name, address and pier number. Pick ups of only aquatic plant material will take place on the Mondays listed below, beginning June 11th. Do not include trash, garbage or any other debris in the pile left at the end of your pier. Our weed harvesting crews will not pick up piles which contain any materials other than aquatic plants.
Pick up for the Main Lake will be on Mondays
Pick up for the Inlet and Outlet will be on Tuesdays
Pick up dates:
Mondays - June 11, June 25, July 9, July 23, August 6, August 20
Tuesdays - June 12, June 26, July 10, July 24, August 7, August 21
For those of you who would like more information on zebra mussels here are some web sites to check:
http://nas.er.usgs.gov/queries/factsheet.asp?speciesID=5
http://dnr.wi.gov/org/water/fhp/papers/p1/misszmdo.htm
http://www.invasivespeciesinfo.gov/aquatics/zebramussel.shtml
Piers
New regulations regarding the placement of Piers in Wisconsin waters has gone into effect and an overview of these regulations can be found at:
http://dnr.wi.gov/waterways/recreation/piers.html