Description:
Originating from Central and South America, Ludwigia was introduced to
Australia in 1911. It is a fast growing terrestrial or partially submerged shrub
to 4m tall, usually confined to freshwater creek lines, banks and wetlands. It
is deciduous in Sydney.
Leaves are alternate, lanceolate from 4 to 12 cm long and finely haired.
Flowers are bright yellow, solitary with 4-5 petals. Flowering in mid summer
to early autumn in Sydney.
Fruit erect 4-angled capsules containing around between 1000-3000 sticky,
pepper-like seeds.
Dispersal:
Seed explosion from capsule into water and spread by birds. Seeds readily adhere
to feathers. The number of seeds below dense Ludwigia peruviana can be over 300
000 per sq metre.
Impact on Bushland:
It is vigorously opportunistic, clogging waterways and dominating over all other
water and creek bank vegetation.
Control:
| Manual: |
First carefully remove any seed heads and bag them securely in plastic bags.
Best incinerated, avoid further seed spread. |
| |
Care should be taken not to inadvertantly spread seed attached to clothing. |
| |
Seedlings can be hand pulled, but larger plants will re-shoot unless the majority
of the many long embedded roots is removed. |
| |
Discarded plants left lying on soil may take root. |
| |
Always follow up the control of Ludwigia by rechecking the plant for any regrowth
and the area for any new seedlings. |
| Chemical: |
Please contact your local control authority for
advice on chemical control. |
Similar Species:
Ludwigia longifolia, a new emerging weed of concern in Sydney
North, has grass-like foliage but similar flowers and seed capsules.
Suggested Alternatives:
References:
WEEDeck, Sainty and Associates
|
