TY - JOUR A1 - Jungnikl, K. A1 - Goebbels, Jürgen A1 - Burgert, I. A1 - Fratzl, P. T1 - The role of material properties for the mechanical adaptation at branch junctions JF - Trees : structure and function N2 - Branch junctions are mechanically particularly interesting areas of trees, because they have to withstand a combination of static and dynamic loads, from the stem as well as from the branch. In the present work, the local adaptation of material properties at branch junctions was assessed by mapping microfibril angle and tissue density. Images of the density distribution were obtained by computer tomography (CT). Wide angle X-ray scattering (WAXS) was used to determine the microfibril angle distribution with high-resolution around the junctions. The stem tissue around the junctions showed increased density and microfibril angle, which points towards an optimisation for fracture toughness. The tissue at the branch bases showed low density combined with high MFA, which provides deformability and flexibility and might act as protection of the stem against load transmission from the branch. KW - Branch junction KW - Computer tomography (CT) KW - Microfibril angle (MFA) KW - Notch stresses KW - Wide angle X-ray scattering (WAXS) PY - 2009 DO - https://doi.org/10.1007/s00468-008-0305-9 SN - 0931-1890 VL - 23 IS - 3 SP - 605 EP - 610 PB - Springer CY - Berlin ; Heidelberg AN - OPUS4-22887 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -