Variability of cones and scale surface area of European larch (Larix decidua Mill.)

Abstract

Abstract The article describes the shape of the cones of the european larch (Larix decidua Mill.) using the fourth degree polynomial fitting function. The material is from the seed orchard of the Barycz Forest District. The curves were used to calculate the area and volume of single cones. it was not possible to generalize the formulas to calculate the surface and volume of larch cones using the described method, due to the large variability of the empirical coefficients of the equations. Finally, to calculate the area and volume of the cones, the formula to determine the solid figure of a cone was used. A constant αs of 0.43 was introduced to the formula. Calculated volume values were compared to actual volumes measured with a water-filled burette. The mean surface area of the larch cones was calculated from the forming function and was 780 mm2, and the volume was 2434 mm3. the values calculated from the cone formulas after taking into account the αs and constants (0.68 and 0.53) were 783 mm2 and 2415 mm3, respectively. the outer and inner surfaces of the seed scales located in the central part of the larch cones were photographed using a Quanta 200 scanning microscope. Specific features of the scales were measured using the Multi Scan Base program. We found that the outer and inner surfaces of the larch scales, as with pine and fir, differed. On the outer side, scales are formed by thick-walled cells with visible, protruding trichomes. thin-walled cells with jagged cell walls are visible on the inside at the location of the wings and seeds. long stem cells, resembling threads, were observed on the surface of the scales, which are absent on pine and fir seed scales.