INDIANAPOLIS (WOWO): This year’s late winter thaw and cool spring weather have slowed the growth of aquatic plants in northeast Indiana lakes. The DNR says this should delay and may even reduce the need to use chemical herbicides to control vegetation in lakes where there are such issues. On a region-wide basis, plant coverage was greatest in 2012, a year marked by an early spring and record warm temperatures with less rainfall. As a result, lakes were much clearer than normal.