| Cumbungi
Typha domingensis
Typha orientalis Typha latifolia.
Family: Typhaceae
Growth Habit: Cumbungi are tall, reed-like, aquatic plants that
have an extensive creeping root system below the water. The long strap
like leaves and seed heads can grow to 2 metres high.
Type of plant: Semi-aquatic, perennial herb.
Flowers: The flowers of the Cumbungi are extremely small and hundreds
of thousands of them are organised into cylindrical heads on the flowering
spikes, commonly called bull rushes.
Fruit/Seed: Small spindle shaped seeds. Seed production has been
estimated to be as high as 17 million seeds per square metre of infestation
depending on the type of Cumbungi species.
Dispersal: The spreading root system of the Cumbungi increase
the size of existing colonies each year. The seed has a feathery attachment
which helps it to be carried by the wind and float on the water to new
sites. The seed is also carried to new places on the feet of animals and
birds, and on earth moving or agricultural equipment.
Distribution: There are two native types of Cumbungi; the Narrow
Leafed Cumbungi (T. domingensis) and the Broad Leafed Cumbungi
(T. orientalis) and one introduced species Cumbungi
(T. latifolia).
Status: Cumbungi is a Declared Noxious Weed in some parts of New
South Wales and a Declared Secondary Weed in Tasmania. As Cumbungi is
part of the natural ecosystem in Tasmania and as it is widely distributed
throughout the state, aiming at total eradication is both undesirable
and impractical. It needs to be controlled in situations where it is causing
problems.
Weed Impact:
- Early Tasmanian literature suggests that Cumbungi was a lot rarer
in the past than it is now. Severe droughts in 1967-68 lead to an increase
in the number of farm dams and irrigation systems, areas ideal for colonisation
by Cumbungi.
- Run-off from paddocks that contain stock manure and/or excess fertiliser
has increased the chances that Cumbungi will become established.
- Cumbungi can rapidly spread throughout a dam or irrigation channel,
restricting the water flow, increasing the rate of siltation and by
altering the water flows actually increasing the risk of flooding and
erosion.
- Because of the large amounts of organic matter produced it can cause
problems with water pollution when the leaves die off and start to decompose.
- Cumbungi can over a period of time greatly decrease the amount of
water being stored in farm dams and increase the amount of maintenance
necessary.
- Although considered to be an aquatic weed, Cumbungi has recently established
itself along roadsides in table drains that do not have permanent water.
This has lead to an increase in the amount and cost of routine maintenance
of these drains.
- As a natural part of the Australian wetlands, stands of Cumbungi provide
cover, food nesting places for water birds and other native animals
as well as habitats for aquatic insects, native fishes, freshwater invertebrates
(yabbies etc.) and frogs.
- The plant protects the sides of creeks, lakes and ponds from erosion.
- The prolific growth provides a natural mulch for adjoining foreshores.
Cumbungi - Control
Methods
| Control |
Time Applicable |
Notes |
| Grubbing |
Autumn, spring, summer |
Best with small plants- ensure all roots are removed.
|
| Excavation |
All year |
Mechanical removal of larger infestations is advisable
to minimise the chance of herbicides entering waterways. Ensure
excavated material is disposed away from dam so it can dry out and
die. Grubbing will be a necessary follow up as mechanical excavation
may not remove all roots and rhizomes. |
| Cultivation |
Autumn, spring, summer |
For small infestations with low water levels, this
method can be effective. |
| Cutting |
January and every 4-6 weeks following |
When the plant is well advanced with flowering (Dec
to Feb) cut the plant 50-150mm under the water starving the plant
of oxygen. Repeat every 4-6 weeks until winter. Repeat process in
coming years as required. |
| Spraying |
Late December-February |
Apply a herbicide registered for use in waterways
in period between male flowers opening and 6 weeks after female
flowers open (usually December- February). Avoid run off or spray
drift entering water. |
| Wiping |
December- February |
Using a wiper minimises the risk of run-off and spray
drift and applies an even amount of chemical on the target plant.
Check with DPIWE for information on herbicides appropriate for this
method. |
N.B. Always
check the herbicide label before use.
|