苗木运输示意图(5)挖坑坑径的大小应根据根系或土球大小、土质情况确定。

Schematic diagram of seedling transportation <br>(5) <br>The size of the pit should be determined according to the size of the root system or soil ball and the soil quality. Under normal circumstances, the hole diameter should be 20-30cm larger than the specified root system or soil ball; for extra-large trees, it can be deepened or widened. <br>The diameter of the pit should be consistent up and down and in the shape of a barrel. <br>The excavated topsoil and subsoil should be piled on both sides of the tree pit. Topsoil is mature soil with high organic matter and microbial content. When backfilling soil, the topsoil should be backfilled first, which is beneficial to the growth of tree roots; the subsoil should be backfilled or used as a cofferdam.

Schematic diagram of seedling transportation<br>(5) Digging a pit<br>The size of the pit diameter should be determined based on the size of the root system or soil ball, and the soil quality. In general, the pit diameter should be 20-30cm larger than the specified root system or soil ball; For oversized trees, it can be deepened and widened.<br>The pit diameter should be consistent from top to bottom, forming a circular barrel shape.<br>The excavated topsoil and subsoil should be stacked separately on both sides of the tree pit. The topsoil is mature soil with high organic matter and microbial content. When backfilling, the topsoil should be backfilled first, which is beneficial for the growth of tree roots; Fill or use as a cofferdam after the bottom soil.

Schematic diagram of seedling transportation<br> (5) Digging a pit<br> The size of pit diameter should be determined according to the size of root system or soil ball and soil quality. In general, the pit diameter should be 20-30cm； larger than the specified root system or soil ball; For extra-large trees, it can be deepened and widened.<br> The pit diameter should be consistent from top to bottom, in the shape of a barrel.<br> The excavated topsoil and subsoil should be stacked on both sides of the tree pit respectively. Topsoil is mature soil, with high content of organic matter and microorganisms. When backfilling, the topsoil should be backfilled first, which is beneficial to the growth of tree roots; The subsoil is filled or used as cofferdam.