Strategic tree and forest establishment and regeneration on the Southern Tablelands
Design and Intention
Climate Change and Tree Selection
Climate change is going to cause more disruption to weather and climatic patterns.
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temperatures will be warmer with more extremely hot days and heatwaves
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rainfall will be less regular and rain events will be more intense leading to more droughts and floods
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spring rain will lessen
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dangerous fire weather will last for longer
While annual rainfall is predicted to be stable, or even increase marginally, higher temperatures will increase evaporation causing higher evapotranspiration and lower soil moisture levels.
Droughts will occur more frequently and may be longer and more intense than we have experienced so far. In fact, under current predictions, drying is expected to cause a complete change in vegetation communities, with wet regions like rainforests and alpine areas disappearing altogether. Part of this process is expected to see the extinction of plant species that cannot cope with the new conditions.
This makes selecting the right species critical, but unfortunately, we do not know the thermal and drought tolerances for most tree species because they have not been exposed to their climatic extremes. We can only judge that by looking at the conditions that species can tolerate now and use it as an indicator. If a tree species lives in western NSW now, we assume it will be able to cope to conditions in southern NSW in the future under the worst climate predictions.
A tree planted today will be mature in 2070. This means that all trees planted now are in fact being planted into future conditions. Those trees will have to be able to survive drought, extreme heat, irregular rainfall and flooding.
Design
Planting design is important in establishing plantings or gardens that will grow well, and be functional and viable. It is important to consider the site qualities and the intended uses of that site. Past use, aspect, slope, soil types, microclimates and access will all play a part in forming a clearer idea of what can and can’t be done on a site. Identifying limitations and opportunities is key in planning any tree planting. Perhaps every bit as important is considering how the site will change over time given the choice of trees for plantings.
If you have multiple uses planned, thinking based on usage or management zones can be helpful. Potential zones might include:
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Garden around the house that are attractive and buffer climatic extremes such as heat and frost.
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Vegetable gardens and orchards within close access of a house.
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Plantings for driveways, roadways and access tracks to reduce dust and noise or create privacy.
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Riparian zones such as dams, drainage lines and creeks.
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Paddock or field zones, considering agricultural and seasonal use.
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Native vegetation zones for biodiversity.
Goals
Farm design is critical for farm profitability. Putting poor land management choices in place can be costly and represents a missed opportunity. It can even lead to severe damage to the land, leaving it profitless into the future.
A good plan starts with developing a clear idea of what you want to achieve. Trees can be implemented in design for a multitude of uses including:
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Stock protection
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Windbreaks
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Fodder
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Wood for fuel
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Timber growing
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Fruit and nut production
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Honey production
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Floristry
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Biodiversity
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Farm aesthetics and privacy
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Land restoration, erosion control and bioremediation
Site Considerations
When designing the location and type of plantings, first take a critical look at the sites available by establishing a detailed site map.
Title documentation and council records can be useful. The Queanbeyan-Palerang Regional Council offers an online GIS service with detailed aerial imagery showing title boundaries and fire risk ratings, which can be searched by address. Selection and drawing tools can be used to select areas, show boundaries and give land area and perimeter measurements. The maps created can be exported.
Queanbeyan-Palerang Regional Council GIS
Aerial imagery for all of NSW can be found at
When looking at sites, note land features such as:
1. Topography
Slope and aspect will have a large influence on other features including water movement, soil and vegetation types. South-facing slopes stay cool and wet, west-facing slopes get the hot summer afternoon sun and are dry. Steep slopes with high run-off may be eroded.
2. Water
Map out the natural watercourses, drainage lines, inundation zones, boggy areas, wetlands and dams. These will be important for preserving water in the landscape and for tree species choice, as well as improving water quality for stock health and biodiversity. Look for any signs of salinity or erosion that need to be ameliorated.
3. Soils
Soil type affects where plants grow. Soil determines water holding capacity and nutrient levels, and can determine the success or failure of species in plantings. Use the visual soil assessment method and/or get soil tested through a lab.
4. Site microclimates
Identify damaging and prevailing wind directions, frost hollows or frost-free areas, more humid areas near water, hot plains or slopes, areas that receive a lot of shade.
5. Remnant native vegetation
Native vegetation is a good guide to local species and to where they grow best in the landscape. Native vegetation is valuable for biodiversity and ecosystem services, and can be incorporated into new plantings.
6. Services and infrastructure
Check for location of easements, overhead wires and underground services, and do not locate plantings in those areas. Consider whether existing fence lines are in the right locations, or whether they might be better positioned somewhere else.
7. Past use legacies
Are paddock trees in decline due to overgrazing and compaction? If there are significant weed populations, could they be controlled or removed by establishing plantings in those sites, reducing weed control costs.
Mostly, get out, take a good walk around. Look critically and creatively at what you see. Talk to neighbours and to Bungendore Landcare members to help develop your ideas.
