Chen Collection, Middle Volume
Radical: Tree (mù)
柆
Kangxi stroke count: 9
Page 518, Entry 11
According to the Compilation of Rhymes (Jiyun), the pronunciation is la.
As defined in the Analytical Dictionary of Characters (Shuowen Jiezi), it means to break wood. It is the same as the character pronounced la.
In the Records of the Grand Historian (Shiji), the phrase reads: To destroy the withered and break the rotten. In the Rhapsody on the Capital of Wu (Wudu Fu) by Zuo Si, it appears as destroyed and shattered. All of these instances are written using the character pronounced la.
The Correct Meaning Guide (Zhengzitong) states that the form pronounced la is the standard.