The Traprock region
The country varies from flat to hilly. Much of the region is classified as not suitable for cultivation with pastoral use only possible with careful management.
There are areas of pasture improvement and intensive crop production. Constraints include susceptibility to water erosion, stoniness in the shallow skeletal soils, low to very low water holding capacity and, for overgrazed areas, susceptibility to sheet erosion. Some areas are inaccessible and deeply dissected with extremely rough land-surfaces.
Traprock soils are generally shallow with a high content of angular parent rock. The dominant soils are:
- Gammie which is very shallow to shallow, gravely, hard setting loams to clay loams with dark brown to brown surface soil, over a brown to yellowish brown or bleached acid subsoil.
- Karangi which is a shallow to moderately deep, gravelly soil with a hard setting brown to dark brown, loam to sandy clay loam surface soil over a bleached A2 horizon with increasing gravel to 15 – 30 cm, over coarse blocky or columnar, reddish brown, brown or yellowish brown acid to neutral clay subsoil.
- Glentanna which is sallow to moderately deep soil with a hard setting, gravely, dark brown or brown loam to clay loam surface soil, infrequently underlain by a bleached A2 horizon to 10 – 20 cm, over brown or reddish brown, blocky, acid to neutral clay subsoil.
Soil fertility status is extremely variable but more commonly fair to low. Soil sodicity is commonly high in the gravelly texture contrast soils.
The common vegetation includes, mixed and pure stands of tumbledown gum, narrow leaf ironbark, silver leaved ironbark, Caleys ironbark, white box, Mugga ironbark, brown box, yellow box, grey box, fuzzy box, spotted gum, rough bark apple and cypress pine. These stands often have a understorey of peach and hop bush and rosemary.
The main grasses encountered on the Traprock are native deep rooted perennials including Queensland blue grass, pitted blue grass, slender bamboo grass, love grass, wire grass, slender rat-tail grass, spear grass and summer windmill grass with some inclusions of exotic coolati grass.
Pasture growth is generally from October through to the onset of frosts in April or May. During this period the pasture is of sufficient quality to fatten sheep and will enable cattle to improve in condition. After the onset of frosts a protein supplement is recommended with the dry feed. Energy supply becomes critical in mid to late winter due to the cold conditions. The country is considered more suitable to high quality wool production with cattle grazing being an area for diversification.
The main landuse within the Traprock Catchment is grazing, with the catchment supporting various breeds of cattle, sheep and goats.
Native pasture makes up the largest percentage of grazing resource in the catchment. The average carrying capacity of the Traprock region is approximately 1.5 Dry Sheep Equivalent (DSE) per hectare, although this can be as high as 2.5 DSE on good quality open pastures. There are some areas where pastures have been modified with clover, introduced grasses and even lucerne but these are generally confined to small areas.
As changes to land use have evolved among members, there are now significant horticultural enterprises within the Traprock region, often conducted in conjunction with wool production. Crops include wine grapes, stone fruits and olives. Members have also invested in other animals including water buffalo and camels.
The majority of Traprock properties lie within the headwaters of the McIntyre Brook and Dumaresq River systems.
The Traprock region provides the main catchment area for two of the major dams in the Border Rivers Catchment. Glenlyon Dam is located on Pike Creek with a capacity of 254,000 megalitres (ML) while the Coolmunda Dam, with a capacity of 74,000ML. These dams provide the main body of regulated flow to the MacIntyre Brook river system. Most of the water from these dams is used outside the Traprock region. Some properties have water storages that are used for irrigating intensive crops or pasture.
Temperatures vary from moderately hot in summer to cold winters.
The average annual rainfall ranges from more than 800 mm in the east of the catchment to approximately 620 mm in west. The region has a summer dominant rainfall, with the main rainfall months between November and March. Annual evaporation potential ranges from approximately 1200 mm in the east to 1750 mm in the west.
Native & feral animals
The region supports some viable populations of native animals such as the Black-striped Wallaby, Red-necked Wallaby, Eastern Grey Kangaroo, Koalas and Platypus.
Other mammalian species found in the catchment include the Short Beaked Echidna, Fat Tailed Dunnart, Chocolate Wattled Bat and some rare species such as the Large Eared and Little Pied Bats. Common bird species include the Southern Boobook, Barn Owl, Tawny Frogmouth Owl, Kookaburra, Magpie, Galas, Lorikeets, Pelicans, Ducks, Cormorants, Emus, the Australian Brush Turkey and Brown Quail. Reptile species include Wood Gecko, Lace and Sand Monitor, the Shingleback and the Brown Snake.
The Traprock is particularly important for bird habitats, with a tree cover of at least 28% of the landscape and vegetation patches distributed across the landscape. The catchment also supports a large range of amphibian species including the commonly found Beeping Frog and the Barking Frog. Other aquatic fauna includes freshwater crayfish, the Australian water rat, Murray Cod, Freshwater catfish, Golden Perch and Silver Perch.
There are many, often detrimental, introduced animals in the region including wild dogs, goats, rabbits, cats, foxes as well as feral pigs. Introduced aquatic species include European Carp, goldfish and mosquito Fish.
Within the Traprock region each of the relevant shire councils has developed comprehensive pest management plans.
Identified within each of these strategies are the pest plants of high, medium and low priority to the Council. Collectively throughout the catchment, the high priority weeds (in no particular order) are Parthenium, Harrisia cactus, Mother of Millions, African Boxthorn, Annual Ragweed, Blackberry, Firethorn, Groundsel Bush, Honey Locust, Privet and Fireweed.