Development of leaf sampling and interpretation methods for Almond


According to a survey of almond growers and consultants in California, leaf sampling and comparison of leaf nutrient concentrations with established critical values (CV) does not provide sufficient guidance for nutrient management. Two explanations for this observation are possible. 1) The current CVs are incorrect or not useful for the decision making process due to lack of sensitivity or inappropriate timing. 2) There are systematic errors in the manner in which critical values are used. The goal of this research is to conduct a systematic examination of leaf sampling protocols and their use in decision making. Preliminary data indicate that leaves from spurs with local fruit load seem to be more suitable for assessing plant nutritional status than leaves from spurs without local fruit load. In addition, preliminary evidence suggests that the death of loaded spurs may be attributable to a local nutrient deficit through out the season.