Likely situations for revegetating with non-grazing species

1. Salinity and waterlogging
The current suite of commercially productive trees are not highly salt- or waterlogging-tolerant, but it is difficult to specify salinity levels (and at what depth) for these species because tree root systems can be much deeper than saltland pastures. The overall conclusion is that there are no salinity measurements that can be made that will guarantee success over the long time frames associated with commercial forestry.

If visual amenity and conservation are the primary motivations behind revegetating with non-grazing species, then a much higher ‘success’ rate is likely and this option can be used on virtually any category of saltland by varying the species planted.

2. Climate and soils
Successful agroforestry and farm forestry enterprises are most commonly found where annual average rainfall exceeds 600 mm and where processing or port facilities are close by. However, trees grown on saltland often have the advantage of access to a shallow, albeit salty, watertable which theoretically could make forestry possible in rainfall zones lower than 600 mm. The limiting factor then is more likely to be levels of soil salinity and waterlogging rather than the availability of soil moisture.

There are non-commercial species available for virtually all climate and soil combinations other than where the salinity is extreme.

3. Indicator species
Sites that might be suitable for trees are typically characterised by salt tolerant grasses of the medium to high rainfall zone such as barley grass, Yorkshire fog, prairie grass or annual ryegrass and perhaps sea barleygrass, although the latter tends to colonise land too salty for most trees and certainly too salty for commercial plantings. There are non-grazing options for all classes of saltland that will support saltland pastures.

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