FOREST COMMUNITIES

Eucalyptus viminalis (white gum) wet forest

Eucalyptus viminalis wet forest is a wet sclerophyll community with a typical understorey mixture of small and broad-leaved shrub species. It occurs mainly on fertile, well-drained sites. The dominant species, Eucalyptus viminalis generally forms an even aged stand of tall and well-formed trees. In sites that are drier or have a higher fire frequency the understorey may be low with a sparser tree cover.

Eucalyptus viminalis wet forest is found mainly on the fertile, well-drained flats and lower slopes of the major valleys of the central north, and less extensively in the north-east, east and south-east. It is often present on a substrate of basalt or alluvium (sediment deposited by flowing water, as in a flood plain).

The community is dominated by E. viminalis. Trees can exceed 60 m on fertile sites. Eucalyptus viminalis wet forest at Evercreech Forest Reserve contains some of Tasmania’s tallest trees reaching nearly 90 m. Old-growth stands are uncommon - most stands are regrowth to 40 m.

Eucalyptus obliqua (stringybark), E. delegatensis (gumtopped stringybark) Acacia melanoxylon (blackwood) and A. dealbata (silver wattle) are sometimes present as sub-dominants, with E. regnans (giant ash) occurring occasionally as a sub-dominant in the north-east.

Most sites have a typical wet sclerophyll understorey containing shrubs such as Pomaderris apetala (common dogwood), Olearia argophylla (musk) and Coprosma quadrifida (native current). Ferns, including Dicksonia antarctica (soft tree fern) on wet sites and tall Pteridium esculentum (bracken) on drier sites, are common. On drier or less fertile sites the understorey is more diverse, with dry sclerophyll shrubs including Pultenaea juniperina (prickly beauty) and Lomatia tinctoria (guitar plant). Rubus fruticosus (blackberry) and other weeds are common on disturbed sites. In many cases where Eucalyptus viminalis wet forest occurs as remnants in agricultural regions where the bush is heavily burnt and an understorey of bracken may dominate.

This forest community is considered to be endangered, 100% of the remaining area is required to be protected to meet both statewide and bioregional reservation targets.

EUCALYPTUS OBLIQUA (STRINGyBARK) WET FOREST

Eucalyptus obliqua (stringybark) wet forest is a tall to very tall wet sclerophyll or mixed forest community. It is one of the most widespread forest communities in Tasmania, occurring extensively throughout the north-west, central north, north-east, east and south-east of Tasmania in regions of relatively high rainfall and on a number of different substrates. Eucalyptus obliqua (stringybark) wet forest is characterised by emergent E. obliqua trees over a wet sclerophyll (broadleaf shrub) or rainforest understorey.

Across its distribution range E. obliqua wet forest often occurs in pure stands. In areas with fertile soils and high rainfall E. regnans (giant ash) may co-occur with E. obliqua. The forest is often composed of tall to very tall trees with well-formed trunks that are approximately two-thirds of the total height of the tree. In regrowth trees, the crowns are relatively small. Mature trees can form large spreading crowns. 

In wet sclerophyll forests on relatively dry sites, E. viminalis (white gum) is a frequent co-dominant. This is either replaced or co-occurs with E. globulus (Tasmanian blue gum) in eastern and south-east Tasmania. At altitudes above 300 m E. dalrympleana (mountain white gum) replaces E. viminalis. On alluvial flats in the north-west E. brookeriana (brookers gum) is a frequent co-dominant, while E. nitida (western peppermint) is the most common peppermint co-dominant in the north-west, and E. amygdalina (black peppermint) in the central north and north-east. At altitudes above 600 m or in areas of cold air drainage, E. delegatensis may co-occur with E. obliqua. In mixed forest understorey rainforest trees will include Nothofagus cunninghamii (southern beech), Atherosperma moschatum (sassafrass), Eucryphia lucida (leatherwood) and Phyllocladus aspleniifolius (celery top pine). The lower understorey in this wet E. obliqua forest is typically composed of broadleaf shrubs, the most common including Pomaderris apetala (common dogwood), Nematolepis squamea (satinwood) and Olearia argophylla (musk), with a high number of ground ferns.

This community is well reserved on a statewide basis, though under-reserved within the Northern Slopes bioregion, requiring 15% reservation of its1750 extent to meet bioregion reservation targets.

EUCALYPTUS OBLIQUA (STRINGYBARK) DRY FOREST

Eucalyptus obliqua dry forests are dominated by E. obliqua trees typically of medium height (20 - 30 m) and with well-formed stems approximately half of the total tree height. In infertile exposed coastal conditions, the community may have a tall, uneven understorey while canopy trees may have a mallee form. The shrubby understorey is typically dense and diverse, and the ground layer sparse.

E. obliqua dry forest is widespread in north, east and south-east Tasmania. It occurs extensively from sea level to about 600 m. The community is generally associated with several substrates, such as, dolerite, mudstone, granite and sandstone.

E. obliqua dry forest is easily distinguishable from other forest communities by the dominant eucalypt and the dry shrubby or heathy understorey. Within the Reserve this community grades into E. obliqua wet forest which is characterised by an understorey of broadleaf shrubs rather than the small leaved heathy species in the dry forest. E. obliqua wet forest also tends to be much taller than E. obliqua dry forest.

Eucalypt dominated dry sclerophyll forest generally have a multi-aged structure. Dry E. obliqua forest generally consist of a taller shrub layer, where species such as Acacia dealbata (silver wattle) and Acacia melanoxylon (blackwood) are frequently present. The lower shrub layer is generally dense and species-diverse, and the ground layer sparse. The exception to this is frequently fired sites, where the shrub layer is sparse and species-poor, and the dense ground layer is dominated by Pteridium esculentum (bracken). Where the shrub layer is dense, common species include Acacia dealbata (silver wattle), Exocarpos cupressiformis (native cherry), Allocasuarina littoralis (black sheoak), Lomatia tinctoria (guitar plant) and Epacris impressa (common heath). On siliceous substrates (e.g. granite and sandstone), the understorey may tend more toward a heathy/shrubby understorey with species including Amperea xiphoclada (broom spurge), Aotus ericoides (golden pea) and Leucopogon ericoides (pink beardheath). Occasionally, on siliceous substrates the understorey can be grassy, often with the only shrubs being Acacia dealbata.

This community is well reserved both on a statewide and bioregional basis.

Non Forest Communities - Riparian vegetation and wetlands

Riparian lands are generally highly productive and due to this much of Tasmanian’s riverbanks have been cleared for agricultural purposes. A good cover of riparian vegetation is important for many reasons. Vegetation abutting waterways protects water quality; filters water moving across the soil surface;

provides food and habitat for aquatic plants and animals. Removing or disturbing riparian vegetation can alter the physical and chemical properties of the adjoining water body, adversely affecting its aquatic organisms. Removal can also cause scouring and collapse of stream banks. Riparian scrub is listed as vulnerable statewide. A wetland and riparian area are found in the northern section of the Reserve shown in the above picture.