Imperial - The giant salvinia, a virulent water weed that has clogged waterways in Louisiana and Texas, has now been found in the All-American Canal.

The finding comes on the heels of the first discovery of the weed in the lower Colorado River on August 5, 1999.

going to be worse than hydrilla because it spreads so fast."

Giant salvinia can quickly grow to clog intakes for irrigation and electric generation. Giant salvinia, a free-floating aquatic fern native to Brazil, can double its size in as little as two and a half days. There are reports

that the weed can grow to a size of about 40 square miles within a few months. It has become an enormous ecological and economic problem in New Zealand, Australia and South Africa. Giant salvinia is illegal to possess in the United States. Its appearance in United States waterways has been linked to nurseries in Texas, where it was grown for aquarium use.

The plant has oblong floating leaves, ½ to 1 ½ inches long. As plants mature and aggregate, the leaves fold and compress into upright chains. Because it grows as a dense floating mat, giant salvinia reduces oxygen content and degrades water quality for fish and other aquatic organisms.

Giant salvinia is spread when fragments break off. Boats and jet skis moving from infected water can spread it. Luker said that fragments of giant salvinia have been found along the All-American Canal from Imperial Dam to the East Highline Canal. Luker urged anyone seeing the giant salvinia within Imperial County to contact his office at 339-9820.

water weed. In 1977, hydrilla threatened the All-American Canal and the district's 1,600 miles of canals. IID's response was to work with state and federal officials to find a biological control. The answer was the triploid grass carp, which has a genetic makeup that renders the fish unable to reproduce.

IID now operates a fish farm that produces the sterile carp with a voracious appetite for hydrilla. The carp have eradicated hydrilla in most of its canals and keeps it in check elsewhere. The fish farm has been so successful that the district now sells its fish to others interested in biological weed control. It is not yet known if triploid grass carp eat giant salvinia. IID officials hope to find out once they get the state and federal permits needed to handle the weed.   

More information and photos of giant salvinia are available on the Internet at