Abstract:Forest canopy greenness and tree-ring widths are important indices describing the processes of forest growth. Questions about the relationships between the two indices and their temporal stability are still not completely answered. The canopy greenness index calculated from remote sensing maps is continuous in space, whereas tree-ring width is a comprehensive index that represents the health of the sample sites. Research concerning the relationship between canopy greenness and tree-ring width could enhance the understanding of growth conditions from multi-perspectives and help transform growth conditions of forests at different spatial scales. We collected increment cores from a Pinus densiflora forest at four sample sites with different health conditions in the Mengshan Mountains of Shandong Province and analyzed the relationships between enhanced vegetation indices and tree-ring widths. We found that 1) the variation in tree-ring width was significantly caused by the variation in forest canopy greenness in April and June for healthy forests as calculated using the Granger causality analysis, whereas the relationship was complicated for unhealthy forests. April and June represent the green-up period of the growth season, and according to the results, this green-up period was closely related to radical growth; 2) canopy greenness in other months and radial growth did not have a causality relationship, rather they were both driven by other environmental factors, especially climatic factors; and 3) we used superposed epoch analysis to determine the influence of canopy greenness decrease events on radical growth, and radical growth recovery following the canopy greenness decrease events. Moderate canopy greenness decreases were not always accompanied by a decrease in radial growth; however, if radial growth had already started to decline before the severe greenness loss, then the decrease would continue for five years after canopy greenness decrease event. Radial growth experienced difficult recovery after moderate canopy greenness decrease events. We identified two or three severe canopy greenness decrease events during 2000 to 2014. After these events, radial growth significantly decreased and continued to decrease for years. Radial growth was not completely recovered five years after severe canopy greenness decrease events. The results showed that changes in forest canopy greenness could not represent the beginning of forest stress or the process of forest restoration. Correlations between canopy greenness and tree radial growth existed only in healthy forests. Declines in canopy greenness strongly influenced radical growth and was difficult to recover after losses in greenness.