Relationships between crown condition, tree nutrition and soil properties in the coastal Picea abies forests (western Finland)

The state of health of 30 Norway spruce (Picea abies L. Karst.) stands located on the uplifting coast of western Finland was examined in 1992. Relationships between crown condition, elemental concentrationsof the needles, organic layer properties and soil type were studied using sitewise data. The site scores along the first axis of the Principal Component Analysis for certain needle and organic layer variables were used as the site fertility index. The spruces in the study area showed a higher level of defoliation and this occurred in younger stands than elsewhere in southern Finland. Defoliation and discoloration correlated positively with stand age, and negatively with the site fertility index. Low N and Cu concentrations of the needles were found in older stands where spruces were highly defoliated and discolored. Boron concentrations of the needles were highest in these stands.Total N of organic layer and extractable S concentrations were negatively correlated with stand age, defoliation and discoloration. The results suggest that poor crown condition of the coastal spruce standsis related to natural soil factors such as periodic water-logging and low fertility. Long-lasting soil frost as a consequence of thin snow cover might be an additional stress factor impeding water and mineral nutrient uptake in the beginning of the growing season. [ABSTRACT FROM AUTHOR]