Water Hyacinth, Eichhornia crassipes Overview. Short description of Eichhornia crassipes, Water Hyacinth Water hyacinth is a striking floating aquatic plant native to tropical regions of South America. Some petioles are greatly swollen, the leaf blade is linear to cordate with parallel veins. It produces a tall spike of blue to pink (or occasionally yellow) flowers, but these have yet to be observed in the UK. Description of Eichhornia crassipes, Water Hyacinth status in GB Distribution map Eichhornia crassipes, water hyacinth, is tropical aquatic plant that has been recorded from around 25 sites in GB but has rarely persisted due to frost. Habitat summary: Eichhornia crassipes, Water Hyacinth Water hyacinth has been recorded in ponds, fishng lakes, ditches and canals, although apparently in each case through deliberate introduction. Overview table Environment: Freshwater Species status: GB Distribution from NBN Atlas Native range: Northern South America, Western South America, Brazil, Southern South America Author's name: R.V. Lansdown (edited by Kevin Walker, June 2017) Functional type: Land plant Last updated: September 8th 2017 We try to keep these factsheets up to date, however if you notice any issues please contact us Status in England: Status in Scotland: Status in Wales: Date of first record: Unknown Invasion history: Eichhornia crassipes, Water Hyacinth Origin Water hyacinth is native to the Amazon Basin in Brazil. First Record
Water hyacinth was first recorded in a pond at Godstone (Surrey) in 1982 and the River Wandle (Surrey) in 1992. It has been known from the Bridgwater Canal, Somerset, since 1999. Pathway and Method From the small number of records and the fact that plants appear not to survive the winter, it is likely that each occurrence in GB was the result of separate introductions. However, its occurrence sporadic occurrence along over many kilometres of the Bridgwater Canal in Somerset suggests that it has the capacity to spread over long distances via vegetative fragments. Species Status Water hyacinth is one of the worlds most invasive and troublesome aquatic weeds of tropical regions. It has been widely planted for ornament outside the tropics but has rarely established due to frost sensitivity. Ecology & Habitat: Eichhornia crassipes, Water Hyacinth Dispersal Mechanisms Water hyacinth mainly spreads by transport of fragments as well as movement of whole plants along waterways. It is possible that it may also spread through rhizomes or seed. It's scattered distribution along the Bridgwater Canal in Somerset suggests it does have limited capacity to spread over long distances in GB before plants are killed by frosts.
Reproduction In tropical regions reproduction is through fragments, seed and possibly through growth from rhizomes. In GB reproduction is likely to be limited to the dispersal of vegtative material along waterways. Known Predators/Herbivores None known in GB. Resistant Stages None known in GB.
Habitat Occupied in GB Water hyacinth has been recorded in ponds, fishing lakes, ditches and canals. With the exception of a few canals, occurrences are likely to represent discrete plantings. Distribution: Eichhornia crassipes, Water Hyacinth Since 1982 water hyacinth has been recorded from 27 locations including 6 disctete areas along the Bridgwater Canal in Somerset. Most localities are in urban or coastal parts of southern and central England (Devon, Somerset, Dorest, Wight, Hampshire, Sussex, Surrey, Essex, Middlesex) with isolated occurrences as far north as Flintshire, Derbyshire and Lancashire. Impacts: Eichhornia crassipes, Water Hyacinth Environmental Impact To date water hyacinth has had minimal impact in GB, however, in tropical regions it can cover vast expanses of water bodies blocking light and precluding movement of animals, causing massive economic, ecological and social impacts. Health and Scoial Impact None known in GB, but in tropical countries it can cover vast expanses of water bodies preventing transport and navigation, as well as adversely affecting the aesthetic qualities of wetlands.
Economic Impact None known in GB, but in tropical countries it can cover entire water bodies, preventing navigation and transport, compromising flood control measures and disrupting commercial activities such as fishing and recreation. References & Links: Eichhornia crassipes, Water Hyacinth Identification Stace, C.A. (2010) New flora of the British Isles, Third Edition, Cambridge University Press, Cambridge. Lansdown, R.V. (2009) A field guide to the riverine plants of Britain and Ireland, Ardeola, Stroud, Gloucestershire. Biology, ecology, spread, vectors www.cal-ipc.orgipmanagementipcwpagesdetailreport.cfm@usernumber=45&surveynumber=182.php Management and impact www.cal-ipc.orgipmanagementipcwpagesdetailreport.cfm@usernumber=45&surveynumber=182.php
General Lansdown, R.V. (2009) A field guide to the riverine plants of Britain and Ireland, Ardeola, Stroud, Gloucestershire.