THE INFLUENCE OF FERTILISATION ON SALT (SODIUM CHLORIDE) DAMAGE IN TRANSPLANTED SCOTS PINE (PINUS SYLVESTRIS) AND EVERGREEN OAK (QUERCUS ILEX)

Summary The aim of this study was to determine the influence of a range of commercially available fertilisers on tree responses following salt (sodium chloride) damage to foliar tissue of containerized evergreen oak (Quercus ilex) and Scots pine (Pinus sylvestris). Evergreen oak proved to be more salt tolerant than Scots pine. Tree responses to fertilisation following 6% foliar salt spray were measured by chlorophyll fluorescence, photosynthetic rates, leaf chlorophyll content, leaf necrosis and leaf sodium and chloride concentrations over a nine week period. Tree responses were 20?300% higher in fertilised compared to nonfertilised trees, irrespective of species. In all cases non-fertilised trees had the least capacity to respond positively following salt damage. In addition leaf area, shoot, root, total plant dry weight was higher in fertilised trees compared to non-fertilised ones at the end of a nineweek period. Results of this investigation indicate applications of commercially available fertilisers would be of benefit to induce positive tree response rates and subsequent growth following sodium chloride damage to foliar tissue. Selection of an appropriate fertiliser, however, is important as effects on growth and vitality varied widely depending on the type of fertiliser applied.