Pond weed control

Asked February 10, 2016, 2:47 PM EST

My parents have a pond and quite a weed issue. They didn't put any chemical in the pond last year and the weeds went crazy. Are there any ways to control the weeds without harsh chemicals for this year?

Clare County Michigan

1 Response

First I would evaluate the pond for runoff of water from the surrounding site. Excess phosphorus and nitrogen can cause plant growth and algae growth that would not normally occur. Ponds should not have grass clippings blown into the water when site is mowed. Fertilizer should not be used within 20 feet of the pond and fertilizers with phosphorus should not be used uphill from the pond where water runoff from heavy rains can bring nutrients into the pond. One way to alleviate this problem is to utilize plants that grow well around ponds to help reduce the ability of nutrients from making it into the pond. A great book on pond plantings is called Lakescaping. It is available at: http://www.comm.media.state.mn.us/bookstore/mnbookstore.asp?page=viewbook&BookID=67748&stocknum=310

or another Michigan publication at: http://www.michigan.gov/documents/deq/wrd-nps-landscape4wq_401217_7.pdf

If weeds are viewed as out of control than yes it will require a herbicide to control the plants but it needs to be one that is labeled for ponds. Care needs to be taken if this pond has an outlet to other water ways. If it does it requires permission to treat for weeds from the Michigan DNR. Clare County contacts for the DNR are:

Regions 5, 6 & 7

Bay City Customer Service Center
3580 State Park Drive
Bay City, MI 48706
989-684-9141

Rose Lake Field Office
8562 Stoll Road
East Lansing, MI 48823
517-641-4903

Many resources on pond management can be found at the DNR website: http://www.michigan.gov/dnr/0,4570,7-153-10364_52259_70620---,00.html