On cacti

嶺南雜記：仙人掌，人家種於田畔，以止牛踐，種於牆頭，亦辟火災。無葉，枝靑嫩而扁厚，有刺，每層有數枝，杈枒而生，絕無可觀，其汁入目，使人失明。

The Lingnan zaji [Miscellaneous Notes on the South of the Ridges] says: Cacti are planted along field edges to prevent cattle from trampling [crops] and along walls to resist fire. They have no leaves; their branches are green, tender, flat, and thick, covered with spines. On each layer, there are several branches that fork out as the plant grows. They are not visually appealing at all. Their sap can cause blindness if it gets into the eyes.

* From Wu Qijun 吳其濬 (1789-1847), Zhiwu mingshi tukao 植物名實圖考 (1848 edition), 15.22a-b. 

The cactus pot in my garden