abscission

abscission zone subapical;

离区尖端；

Petiole narrowly winged basally or proximally, with a subapical abscission zone;

叶柄狭翅基部或下部，具一尖端离区；

Tyloses are often found in injured tissue, older wood, and below an abscission layer, and can completely block the conducting vessel.

受损害组织、衰老木材和离层下方位置常发现侵填体，这可以完全阻塞负责运输系统。