45-9 Sat Jan 2 Junk in the trunk: can trees use carbohydrate reserves that are deep in the stem? Furze, ME*; Huggett, BA; Chamberlain, CJ; Wieringa, MM; Aubrecht, DM; Carbone, MS; Walker, JC; Xu, X; Czimczik, CI; Richardson, AD; Harvard University and Yale University; Bates College; Harvard University; Harvard University; Northern Arizona University ; Northern Arizona University ; University of California, Irvine; University of California, Irvine; University of California, Irvine; Northern Arizona University morganfurze@gmail.com
Carbohydrates play a key role in plant physiology and metabolism, yet we know little about their distribution within tree stems. This leaves open questions about whether carbohydrate reserves deep in the stem are available to support tree functions. To explore the availability of reserves, we measured the radial patterns of carbohydrates throughout the year in the stems of temperate trees with contrasting wood anatomy (ring-porous vs. diffuse-porous). We showed that carbohydrates were the most seasonally dynamic in the outermost stem segments for both ring-porous and diffuse-porous trees. However, while the seasonal fluctuation was dampened in deeper stem segments for ring-porous trees, it remained high for diffuse-porous trees. Our results suggest that while deeper stem reserves fluctuated across the seasons, the deepest reserves at the center of the stem were not used to support tree metabolism under normal environmental conditions.
