四分律刪繁補闕行事鈔 3.154

3.154

制意者，《四分》、《明了論疏》：諸俗人外道，謂一切草木有命根，以佛不制此戒故，比丘傷於草木，為他輕訶，令彼獲罪；又與白衣不別，不生恭敬心。故《十誦》名為疾滅正法，復曲制也。餘如壞生戒中說。

Regarding the intent of the prohibition: the Dharmaguptaka Vinaya and the Commentary on the Vinayavibhāṣā state that laypeople and tīrthikas consider all grasses and trees to possess the life-faculty; because the Buddha had not yet instituted this precept, bhikṣus injured grasses and trees, causing others to slight and scold them and thereby incur sin; furthermore, they were no different from laypeople, so feelings of reverence did not arise. Therefore the Daśādhyāya-vinaya calls it an expedient prohibition against the swift destruction of the true Dharma. The rest is as explained in the precept against destroying life.