Water lettuce
Pistia stratiotes, Fam. Araceae
Perennial free-floating aquatic herb resembling the open head of a lettuce, trailing long feathery fibrous roots.
| Weed Category: |
Restricted invasive plants Category 3 Plants declared invasive under the Biosecurity Act 2014, that are present in QLD.
Not to be distributed or disposed of.
|
| Weed: | Yes |
| Form or habit: | Aquatic plants |
| Family: | Araceae |
| Leaf: | Simple Basal Simple, numerous in a basal rosette, spoon- shaped, 30-150 x 20-80mm, conspicuously nerved, often ribbed beneath, spongy and water repellent due to covering of velvety hairs. |
| Flower conspicuous: | Inconspicuous |
| Flower colour: |
Green |
| Flower description: | Minute green coloured, borne in a funnel-shaped spathe 10-20mm long, partially concealed in the centre of the rosette. |
| Fruit conspicuous: | Inconspicuous |
| Fruit colour: |
Green |
| Fruit: | Fleshy |
| Fruit description: | Green, fleshy, ovoid or elliptical berry, about 10 x 5-8mm with 4-15 seeds about 2mm long. |
| Habitat: | |
| Distribution | |
| Food source for: | |
| Toxicity: | No toxicity known |
| Origin: | South America |
| Notes: | Spread by: seeds, seedlings, daughter plants and mature plants are moved by water and wind. Also spread from ornamental ponds during heavy rain events or discarded from aquariums. Invades/threats: slow moving waterways and wetlands, rapidly forming obstructive mats in warm or nutrient-rich water. Notes: introduced as an ornamental for ponds and dams now widely naturalised including recreational water ways in this region. Reproduction is mainly by runners but seeds germinate readily. It can survive long periods stranded on mud. Provides habitat for disease- carrying mosquitoes; has negative impacts on native aquatic plants and animals; can interfere with irrigation, boating and water sport activities. Category 3 restricted invasive plant under the Biosecurity Act 2014, it must not be given away, sold, or released into the environment without a permit. The Act requires everyone to take all reasonable and practical steps to minimise the risks associated with invasive plants and animals under their control. This is called a general biosecurity obligation (GBO). |
| Information sources: | Mackay Regional Pest Management Group (2018) Weeds of the Mackay Whitsunday Region Second Edition. |
