weeds
Serrated Tussock - Nassella trichotoma
local history
Serrated Tussock has had a very significant impact on the landscape of the Rowsley district and beyond. From peak levels in the 1990s, a remarkable improvement has been achieved through concerted efforts by the majority of landowners.
Still, there is a long way to go before Serrated Tussock stops being the biggest weed problem in this landscape. History teaches us that the whole community must be committed to action.
impact
Serrated Tussock is high in fiber and low in protein resulting in no food value for stock. Stock will take more energy to digest Serrated Tussock than they get from it, so will lose condition if they have nothing else to feed on. The fibrous leaves can also ball in the stomachs of stock threatening their lives.
Serrated Tussock can produce over 10,000 seeds per plant per year. These seeds detach from the plant and are readily blown around the landscape during summer. This prolific and mobile nature makes Serrated Tussock able to out-compete and displace native vegetation, turning diverse healthy and productive areas into mono-cultural wastelands.
treatment
With a persistent and integrated approach Serrated Tussock can be beaten
Control measures can include:
Cultivation - only possible on arable land, cultivation can bury seed at a depth at which they won't readily germinate. cultivation is only properly effective when followed by sowing of a competitive crop or pasture.
Chipping - for small numbers of plants it can be feasible to dig the plants out, remove the soil from the roots and leave them to die. This does create disturbance that is readily re-infested, so needs close monitoring.
Herbicide - application of herbicide such as Flupropanate or Glyphosate can be via spot spraying from the ground, for scattered infestations, boom spraying for heavy infestations on accessible ground, or aerial spraying for heavily infested inaccessible ground.
more info
for Serrated Tussock information try the Victorian Serrated Tussock Working Party, for Chemical information try the APVMA or local farm supplies.
Boxthorn - Lycium ferocissimum
local history
The Rowsley area has suffered from very high rabbit numbers and Boxthorns play a large role in this.
impact
Boxthorns have considerable direct impact through displacing native species and making areas inaccessible because of their large tough thorns (thorns known to take out many a car tire). Possibly boxthorn's greatest impact is through acting as rabbit harbour.
treatment
Foliar spraying - for young or inaccessible plants, the leaves of the plant can be sprayed with a woody weed selective herbicide. dead plants can still provide harbour for pests such as rabbits and plants significant thorns will still have the potential to puncture tyre and feet.
Cut and Paint - possibly the most effective measure, well suited to errodable country as the roots remain in the soil. the main stem of the plant is cut about 1 cm above the ground taking care not to get dirt on the cut as this will deactivate the Glyphosate. Within 30 seconds of making the cut, undiluted Glyphosate must be painted on the stump's wound so that the herbicide is absorbed by the plant before the wound starts to calous over.
Grooming - for large and dense infestations a machine that attaches to an excavator can be used to turn the plants to mulch were they stand. Although this is impressive to watch, it has limited application as the mulch is a mat of sharp thorns that are injurious to stock and tyres.
more info
Ag Vic Boxthorn info, Weeds Australia entry on Boxthorn
Spiny Rush - Juncus acuta
history
impact
Spiny rush has a devastating choking effect on waterways displacing all other species.
treatment
As this is primarily a weed of waterways and areas that receive moisture, and so there is a natural restriction to the use of herbicides due to label restriction to prevent off target effects.
Excavators can be used to mechanically remove the plants, but this needs to be done with great care to minimise erosion and associated water quality effects. Any removal must be accompanied by a replacement strategy, and engineered solutions to manage water flow while new desirable species establish is often advisable.
more info
Chilean Needle Grass - Nassella neesiana
history
CNG has been spread around vast areas by roadside slashing carrying the seed on the machinery.
impact
CNG is of lower food value to stock than most pasture species and presents a significant injury risk from it's sharp and penetrating needle-like seeds. It is a tenacious plant that will overrun a paddock if allowed.
treatment
more info
Peppercorns - Schinus molle
history
peppercorn trees are particularly well suited to the conditions or the Rowsley area and are readily spread by birds, and have therefore become very weedy in some areas even though they are not always classified as a weed.
impact
treatment
more info
Willows - Salix sp.
history
impact
treatment
more info
Cacti (Prickly Pear, Wheel Cactus etc) - Opuntia sp.
history
impact
treatment
more info