Studies on relations between acorn productions, dry matter partitioning and annual ring formation process of Quercus crispula

研究了树木物候学调查方法，为明确脆皮栎橡子产量预测提供基础资料。我们开发了一种新的树木物候学方法，利用照片获取客观数据。研究了雌花数与成熟橡子数的关系。丰收年雌花数减少，但雌花数与成熟橡果数之比基本一致。研究了橡实叶片质量与成熟橡实的关系。在每个质量中没有关系。研究了成熟橡实质量与年轮宽度的关系。但我们无法获得足够的数据来明确这种关系。这项调查将继续进行。用针标法研究树木物候与木材细胞形成过程的关系。结果表明，气管在芽张开之前就形成了。但由于年景不佳，无法对橡实成熟时的细胞形态进行研究。雌花数是估算橡实产量的重要因子。

Method of investigation on tree phenology was examined to obtain the basic data to make clear the yield forecast of acorns of Quercus crispula trees. We developed the new method of tree phenology to get objective data using photographs.Relationship between the numbers of female flowers and matured acorns was investigated. The number of female flowers was decreased in a poor crop year, but the ratio of the numbers of female flowers and matured acorns was same value.Relationship between the mass of leaves and mature acorns was investigated. There was no relation in each mass.Relationship between the mass of mature acorns and the width of annual rings was investigated. But we could not obtain the sufficient data to make clear the relation. This survey will be continued.Relationship between the tree phenology and the process of wood cell formation using pin-marking method. It was cleared that the trachea was formed before bud opening. But we could not make investigate the cell form when the acorn was matured because of poor crop years.Number of female flowers was very important factor for estimation of acorn production.