Soil Aluminium

As advised in our September 09 newsletter, we have now adopted the 0.02M CaCl 2 extractable Aluminium (Al) method for assessing potential phytotoxicity for this element. The method previously used (1M KCl extract) had some significant drawbacks in the laboratory and the lower ionic-strength 0.02M CaCl 2 extract is understood to more closely provide information on soil solution Al. Toxicity is only likely in acid soils so this test is recommended when soil pH is below 5.5, and also for sub-soil assessment prior to crop establishment. A technical note "Soil Aluminium Test Interpretation" is now available.