Slasher covers and fans to minimise roadside weed spread
- Authors: Grech, Charles , McLaren, David , Weller, Sandra
- Date: 2010
- Type: Text , Conference proceedings
- Full Text: false
- Description: It has been observed that the seeds of Chilean needle grass (Nassela neesiana) can be spread by the use of machinery to slash or mow roadsides that are infested with this weed. Modification of slashers by the addition of a cover or deck fans that can prevent seed and/or seed heads settling on the top of the slasher appears to be effective. This project compared the relative effectiveness of each type in a Chliean needle grass infestation at a demonstration day held at Greenvale, Victoria, Australia in November 2009.
Detection and prevention of the dispersal of the seeds of Chilean needle grass (Nassella neesiana Trin. & Rupr. (Barkworth)) in hay bales
- Authors: Weller, Sandra
- Date: 2016
- Type: Text , Thesis , PhD
- Full Text:
- Description: Invasive and noxious weeds are well known as a pervasive problem, imposing significant economic burdens on all areas of agriculture, and thus their control and eradication are of central concern to the industry. Whilst there are multiple possible pathways of weed dispersal in this industry, of particular interest to this discussion is how the unintended dispersal of Chilean needle grass (Nassella neesiana) weed seeds, within emergency fodder, may be prevented. Periodic drought is a feature of the Australian climate, which, together with natural disasters of flood and bushfire, necessitates the urgent provision of emergency fodder for maintenance of livestock production. However, previous investigations into weed seed dispersal by this fodder type have revealed a significant risk for the dispersal of a number of noxious weeds well beyond their current range. Because preventive work, relating to detection and eradication of noxious species, is at an early stage of development, the development of faster, more reliable, and non-destructive sampling methods for seed species has become essential. In addition to prevention of weed seed dispersal in fodder, the use of appropriate methods of controlling troublesome pasture weeds in situ is of relevance for addressing established infestations. Whilst silage preservation is one such typical method that can reduce weed seed input into the soil seed bank, there is currently little data on the absolute effectiveness of this method for control of N. neesiana. To investigate whether rapid detection of seeds in bales is possible and how the numbers of seeds in a pasture are linked to the numbers of seeds that may be incorporated into hay bales made from an infested pasture, an investigation of a rapid, non-destructive technique to detect seeds in bales, together with an examination of a pasture to estimate seed density and dispersal prior to baling, were carried out. Additionally, since pastures infested with this weed are of no use for producing hay and little use for grazing, a third experiment was devised, which was an investigation of silaging for preventing inadvertent seed input into pasture soil seed banks. This thesis has shown that this approach of non-destructive core sampling of bales to detect the seeds of N. neesiana, and possibly others, which can be visually recognised, shows promise for those involved in weed control. Similarly, the simultaneous demonstration that silage fermentation is an efficient viable method for both eliminating viability of mature (germinable) seeds of this species while also reducing the probability of injury to livestock from these seeds, confirms that reducing the impact of this weed in agro-ecological systems and on livestock during emergency situations is possible.
- Description: Doctor of Philosophy
Detection, quantification and management of the dispersal of Nassella neesiana (Chilean Needle Grass) seeds in hay bales
- Authors: Weller, Sandra , Florentine, Singarayer , Ambrose, Graeme , Grech, Charles , McLaren, David
- Date: 2010
- Type: Text , Conference paper
- Relation: Paper presented at 17th Australasian Weeds Conference: New Frontiers in New Zealand, Together we can beat the weeds p. 428-430
- Full Text: false
- Reviewed:
- Description: Summary This paper outlines a project that intends to investigate the link between the occurrences of weeds in pasture hay crops and weed seeds in bales. Noxious weed in particular pose a threat to the livelihoods of primary producers in this manner. As an example of a noxious weed, this project will investigate Nassella neesiana, Chilean needle grass. This species is a restricted (noxious) weed that infests roadsides, native grasslands and pastures that may be baled for hay. In Victoria it has the potential to cause significant economic harm to agricultural areas and the trade in fodder and hay. This project aims to develop methods for the detection of weed seeds in hay bales and provide more information about the role of hay machinery in their spread. Later, we will investigate the extent of seed shedding from hay bales during transportation by road. This project will attempt to correlate the percentage cover of N. neesiana prior to harvest with the seed content of bales. Trial core samples from bales indicate that seeds of N. neesiana and other grass species were present. However, a correlation has not yet been established between weed biomass and the seed content of bales.