Document ID: chunk:federal_register_of_legislation:F2016L00045:body:0:p18
Version: federal_register_of_legislation:F2016L00045
Segment Type: other
Provision Reference: 
Character Range: 49193–52171

ecological community, and due to the sensitivity of wetlands to some chemicals, effective control of weeds (particularly non-woody weeds needing chemical control) in the ecological community is challenging. There are several known invasive plant species that have serious impacts on bog flora composition. Most of these species have the capacity to progressively invade an undisturbed occurrence of the ecological community and the rate of invasion is greatly exacerbated by intensive disturbance, such as by bushfire, feral horses and pigs. The interaction between large fires and weeds has been identified as a key threat to the resilience and function of alpine ecosystems (Williams et al., 2008). Post-fire studies in the Kosciuszko National park have found a significant increase in both diversity and average numbers of weeds impacting on bog sites (Hope et al., 2005).

Although there are currently almost no weeds in the ecological community at higher altitudes, there are areas of the ecological community in subalpine areas with localised and specific weed occurrences. That these weeds occur in the ecological community at all indicates they are likely to become a serious threat in the future (K. McDougall pers. comm., 2014). Weed invasion has the potential to reduce or destroy the composition of the ecological community. Some exotic weeds, such as Juncus spp. and willows (Salix spp.), have the capacity to establish in such abundance that they permanently alter floristic composition and structural integrity, as well as affecting the overall hydrology of the area (McDougall, 2007).

Weeds - woody

Willow (Salix spp. – particularly Salix cinerea) invasion into the ecological community can cause major structural impacts and fundamental alteration of root structures and hydrology, as has occurred in many other river and freshwater systems (Cremer, 1995; 1999). Willows are a significant issue, particularly in Victoria, where willow spread and infestation has increased in recent years due mainly to repeated major fire events.

Weeds - Non-woody

A number of herbaceous weeds currently threaten the Alpine Sphagnum Bogs and Associated Fens ecological community and in some cases have become widely established. For example, Juncus effusus is now in such abundance in some previously grazed areas (e.g. Rocky Valley on the Bogong High Plains) that it is permanently altering the floristic composition and vegetative structure of some bog and fen sites (Walsh and McDougall, 2004; McDougall, 2007).

The ecological community in both Tasmania and the ACT has remained without weed issues, although Eragrostis curvula (African love-grass) has been recently discovered in several high altitude bogs (G. Hope pers. comm., 2014) in the ACT. This invasive grass species is widespread throughout urban areas of the ACT and in surrounding rural districts.

Other herbaceous weed species commonly found in the ecological community include Lotus uliginosus (birds-foot