The management and threat of weeds - a VicRoads perspective.
Jason Horlock, VicRoads Metropolitan North West Region, 499 Ballarat Road, Sunshine, Victoria 3020, Australia.
The challenges for VicRoads weed management are many. Roads are inherently some of the most difficult areas in which to manage weeds. They are linear and experience constant weed seed input and dispersal through almost continuous vehicle movement. Other activities of routine landscape maintenance and in particular the mowing of turf, acts as a primary cause of weed spread.
Limitations of funding promotes compliance with legislation first so that weed species without noxious weed classification are not targeted for treatment with the priority they deserve from environmental perspectives. Even the monitoring of weed populations to evaluate the on-ground effects of weed treatment programs is complicated, costly and the data itself constantly changing.
The impact of current weed policy on VicRoads weed management is predominantly in identifying what sub-set of weeds are targeted for treatment and in what priority order. For this influence to have desirable on-ground outcomes, policy must be as complete and as up-to-date as possible. If not, policy can potentially have an on-ground effect of selectively favouring certain weed species by targeting other weed species that compete for the same areas and resources.
It may even be possible that the rapid spread of tenacious weeds such as Chilean needle grass, has been assisted by their omission from noxious weed listings.
Plant Protection Quarterly (2005) 20 (3) 112-113.