栎属植物的果脐占果皮表面积的4％-37％，是大多数种类吸收水分的主要部分。

The scar, composing 4% to 37% (surface area) of the whole fruit coat, was found to be the main water passage for most species.

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水分由维管束直接迅速地进入果脐，并沿果皮不分化层中的维管束到达果皮各部分，形成一个水分传输的纵向系统。

Water transferred directly and quickly through the scar. From the scar through to the pericarp and ending at the apex, there was a longitudinal passage of water flow.

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