Screening for salt tolerance in native and exotic shrub willow

Non-Peer ReviewedDryland salinity is a significant agronomic problem across the Canadian prairies, with an estimated four million hectares of salt-affected land. The potential exists to make better use of saline marginal lands by developing them into willow plantations as a bioenergy feedstock; however, relatively little is known about the salt tolerance of willow. Apart from limited anecdotal information, no empirical work has been done to examine willow growth on saline soil. The objective of this study was to compare the relative salt tolerance of 37 different native and exotic hybrid willow clones grown under controlled environment conditions on soils with varying salinity. The soils were collected along a hillslope catena influenced by saline seep salinity, containing high concentrations of sulfate salts, which commonly occurs within western Canada. Most willow clones tested in this study were able to tolerate slightly saline conditions (≤ 5.0 dS/m). In addition, several clones (Alpha, India, Owasco, Tully Champion, and 01X-268-015) showed no reduction in growth with moderate salinity (≤ 8.0 dS/m). This work should help to fill the current knowledge gap regarding the salt tolerance of willow and thus provide recommendations for which clones are best suited for establishment on salt-affected soils in Saskatchewan and abroad