Mean concentrations (% dry matter) of free sugars and starch (NSC) in (A) needles, (B) branches, (C) stems and (D) coarse roots of Scots pine, growing at a dry-mesic and xeric site (hedged bars), at six sampling dates during the year 2009. Different letters indicate significantly different NSC concentrations among sampling dates (P < 0.05, lower case letters: dry mesic site, upper case letters: xeric site). Note the difference in scaling of the y-axis between A (needles) and B-D (woody tissues).