16-001014-02A (Ultimate SCMMP)

                                    Salvinia (Salvinia molesta)

                                    Free-floating perennial fern with ‘leaves’
                                    (fronds) in groups of three, consisting of two
                                    floating leaves and a submerged modified
                                    leaf that functions as a root.

                                    Salvinia actively grows throughout the year
                                    and is difficult to eradicate once established
                                    in a water body.

                                    Flowering: Salvinia is a fern so it does not
Photo: Jason Sonneman, DesignFlow   flower. Fruiting bodies containing sterile
                                    spores that hang from the divided leaf.

                                    Reproduction: Salvinia does not produce
                                    fertile spores. Spreads vegetatively by
                                    fragmentation.

                                    Control: Physical removal, chemical, biological

                                    Integrated control strategies that combine
                                    both physical and chemical removal
                                    techniques have proven to be effective at
                                    eradicating small salvinia infestations.

                                    Salvinia weevil (Cyrtobagous salviniae) has
                                    proved to be extremely effective in
                                    controlling large salvinia infestations.



                                    Water hyacinth (Eichhornia crassipes)

                                    Free-floating perennial aquatic plant with
                                    dark green, erect leaves, including stalk, to
                                    60 cm land fibrous, feathery roots to 1 m.

                                    Plants are distinguished by blue-purple
                                    flowers produced on spikes to 15 cm. Some
                                    leaves are also characterised by a spongy,
                                    swollen base that enable the plant to float.

                                    Flowering: October–July
Photo: Jason Sonneman, DesignFlow
                                    Reproduction: Seeds. Daughter plants are
                                    produced vegetatively at the ends of the
                                    stolons and remain attached to the parent
                                    plant until they are broken off by wind or
                                    damage.

                                    Control: Physical removal, chemical, biological

                                    Water hyacinth is very difficult to eradicate
                                    as the seed may remain viable in sediments
                                    for up to 15 years.

                                    Physical removal should be undertaken before
                                    the plants flower and set seed.




                                               Maintaining Vegetated Stormwater Assets Version 1   65