Linear reserves is a term used to refer to the vegetated sections of road, rail, drainage lines and waterways. Some of these reserves on the Victorian Volcanic Plain are the focus of a project that is being run by the Department of Environment Land Water and Planning(DELWP), Corangamite Catchment Management Authority (CMA) and Glenelg CMA with Commonwealth funding. One of the activities to raise awareness of these reserves, has been 2 recent workshops highlighting the biological values of the endangered grasslands. Vanessa Craigie (DELWP) gave a very interesting presentation pointing out the importance of linear reserves in providing habitat for native flora and fauna especially the endangered ones.
Here are some of notes taken during the workshop……..
The types of species found in grassland and grassy woodlands remnants on private land and linear reserves often indicate a difference in management. On private land where there has been no de-rocking, ploughing, cropping or fertiliser, the plants found are usually the ones sensitive to burning and tolerant of grazing. On the other hand linear reserves have species that respond to regular burning so are burning tolerant, have good diversity, few trees and grazing intolerant.
Button Wrinklewort is sensitive to grazing so is now only found at sites where regular burning occurs. The Sunshine Diuris is now only found in one rail reserve when once it was in such numbers it is reported that the ground looked like it was covered with snow and its common name was “Snow in the Paddock”. The Spiny Rice-flower is still seen in a few sites that are burnt. Some adult plants have been carbon dated to be a minimum of 50 years old and have a tap root meters long which helps them to survive but makes them very difficult to transplant if that action is required.
Up to the early 1980’s burning was the regular treatment for rail reserves, but then there was a change to using herbicide instead to make management ‘easier’ and at least 50% of the grassland reserves lost their special ecological values. In the mid-1990’s roadside reserves fell to a similar fate. Often this was not a deliberate attempt to remove the vegetation by an attempt to deal with less volunteers to do the burning and trying to cure the grass earlier to burn early to protect crops. It has resulted in the weed issue we are still trying to deal with today.
Unfortunately it is a bit late, when the more vigorous phalaris has taken over, to worry about the loss of the native grasses. Kangaroo grass which produce less leaf litter resulting in less fuel to burn is safer for volunteers to burn as the flame heights are much reduced. We should still keep burning and need to be mindful of the intervals between burning. If the frequency expands out 5 to 8 to 10 years then this is not good, as the native grasses will smother in their own litter. There needs to be regular biomass removal.
Not only do linear reserves provide space for the last remnants of plant communities they also support a range of insects, birds, lizards, snakes, frogs and small mammals such as dunnarts.
The Remnant Native Vegetation Investigation (VEAC, 2011) highlighted that linear reserves should not just be considered as corridors as they do provide habitat and are very important. Viability depends not on size but on the amount of money needed to manage the site. Big is not necessarily best. Remnants are resistance to disturbance if the soil is left alone. Operate as if the site is protected and minimise disturbance.
When it comes to signage more sites are lost through accidental damage so it is probably better to have them signed.