To prevent algae and other growth from clogging canals, limiting access and affecting water deliveries, NID conducts an integrated program of weed management.With more than 400 miles of canals in Nevada and Placer counties, weed control is a big job for the district.
Over the years, chemical weed control has been the most effective method of keeping the water flowing, but the district is also using new and different methods.
Commercial products used in NID’s aquatic weed control program are applied by licensed applicators under permits granted by the county agricultural commissioner.
Herbicide FAQ’s. Aquatic weed control is generally conducted during the irrigation season, which runs from April into October.
Each year, the district plans and publishes a Seasonal Application Schedule and also notifies nearby water users when applications are planned on various canals.
The district continues to try several innovative and environmentally friendly methods of weed control. These include tests with UC Davis researchers of acetic acid, or common household vinegar that when applied to dry canal bottoms can limit growth of aquatic weeds.
Other tests have included applications of barley straw and corn gluten, berm grading, seeding programs and weed tarps. District specialists have found success in thermal (hot steam) weed control along canal banks and berms.
One successful and rather old-fashioned effort has been the use of goats to control weeds around district reservoirs. Herds of goats, brought in by local agriculturalists, have munched weeds and proven to be successful weed control workers.
Weed Control With Hot Steam
A tractor-mounted thermal weed control unit is the latest tool in NID’s battle to control weeds around canals, reservoirs and easements.
The $17,000 propane-powered unit from Sunburst, Inc. of Eugene, Oregon, uses high temperatures (132 degrees and above) to eliminate seedling weeds. Repeated applications can even eliminate established plants, according to the manufacturer.
NID’s vegetation control specialists say the unit is proving effective as the district seeks to limit its use of chemical weed control.
The thermal unit has been valuable during the wet winter and spring months when other techniques may not be practical. Use of the thermal unit is carefully planned in the warm months because of heat and potential fire danger.