Council looks to tackle invasive plant in Dartmouth's Little Albro Lake

Halifax regional council is looking to curb the spread of an invasive plant species at Little Albro Lake in Dartmouth, N.S.

Yellow floating heart, which is native to East Asia and the Mediterranean, is the culprit.

Staff are recommending the use of benthic mats, or weed mats, to control the infestation, contingent on approval from the province and federal government.

The mats are a blanket-like barrier made out of synthetic or natural materials that can be placed on a lake bottom to block sunlight from the plant to control growth.

According to a staff report, using the mats would be "relatively inexpensive" compared to other weed-control methods, easy to apply, effective and safe.

But using the mats would require approval from Nova Scotia's Environment Department and Fisheries and Oceans Canada.

Yellow floating heart was first reported at Little Albro Lake in 2006 and "quickly grew to dominate the surface of the lake," the report states.

The plant is thick, making it difficult for swimming and boating.

The plants produce hairy seeds, which can attach to wildlife and boat hulls, making it possible to spread to other lakes.

According to the report, area residents have advised their municipal councillor that the plant covers the lake surface, overtakes the lake's native vegetation and restricts any use of the lake for swimming or boating from May to September.

It could take up to three months to develop a pilot project and to get regulatory approval for using weed mats, which would delay an installation until the fall. So, "it may be prudent to delay mat installation until spring 2020," the report said.

The estimated cost of the proposed pilot project is $25,000.