This message had already been conveyed to him when the first wave of scouts returned with the news, so he was naturally prepared early on.
According to the report, the width of the ravine is over thirty meters and the depth is five meters, completely blocking the entire exit. If Zhu Fang weren't here, the rebel army would ignite the ravine, and the troops would find it really difficult to pass smoothly.
Even with Zhu Fang present, there's no guarantee of success. Given the width and depth of the ravine, even if the fire is extinguished, the troops would still struggle to pass through smoothly.
The solution of filling it with stones was Cai Qiuhu's idea.
It's not that they didn't want to use trees; the key is that the rebel army's recent fire burned away all the woods inside the valley entrance, leaving almost nothing. So they can only use stones as substitutes.
