continued The Cazenovia Town Board approved the survey — and its $8,000 price tag — last September to help the board members decide whether or not a chemical treatment program for the lake would be warranted in 2014.
The town previously treated the lake with Renovate (triclopyr) in 2009, 2010 and 2012 in an effort to bring the invasive species Eurasian water milfoil under control. No chemical treatment was applied to the lake last year due to the cost and the shortened timetable to submit permit applications to the state Department of Environmental Conservation.
The conduct the 2013 survey, Johnson sampled and recorded plant species presence and abundance at the same 304 locations previously sampled in 2010, 2011 and 2012, and also an additional four new locations in Carpenter’s Pond, the report said.
According to the report, Johnson and his team collected samples with a dual-headed rake and assigned an overall plant abundance estimate to the amount on the rake. They classified and recorded the entire rake sample as “dense (D)” — more than an armful and difficult to get into the boat; “medium (M)” — an arm full; “sparse (S)” — two hands full; “trace (T)” — a small handful or less; or “zero (O)” — a bare rake. The field crew then separated each sample to individual species, analyzed the separations by recording the species identification and a percentage estimate of each species on site.
The major findings of the report are that the Eurasian watermilfoil was “reduced significantly” in 2009 and 2010, increased in 2011, reduced again in 2012 but then increased again in 2013 from 123 locations in the lake in 2012 to 255 locations in 2013. Of those 255 locations, 33 percent had watermilfoil that was medium or dense in abundance, the report stated.
The 2009, 2010 and 2012 lake treatments with triclopyr “continue to show no significant negative effect on an overwhelming number of non-target plant species,” although the species white water lily and northern watermilfoil did decrease, although that was expected, the report stated. The species coontail, elodea, eel grass and benthic filamentous algae were found in abundance in the target survey areas, and the species flat-stemmed pondweed “increased significantly,” the report stated.
“The very positive high native plant species numbers (richness) present in Cazenovia Lake continue to constitute a very diverse aquatic pant (macrophyte) community providing stability that should slow invasion by non-native species,” the report stated.
The full report can be read on the town’s website at townofcazenovia.org, under the “Caz Lake Restoration” tab.
Jason Emerson is editor of the Cazenovia Republican. He can be reached at email@example.com.