卷一凯特琳第一个POV里有很多关于南方与北方神木林的描写：
对于奔流城的： The godswood there was garden, bright and airy, where tall redwoods spread dappled shadows across tinkling streams
The Tullys kept a godswood, as all the great houses did, but it was only a place to walk or read or lie in the sun.
对于临冬城以及北境地区的： No redwoods grew here. This was a wood of stubborn sentinel trees armored in grey-green needles, of mighty oaks, of ironwoods as old as the realm itself. At the center of the grove an ancient weirwood brooded over a small pool where the waters were black and cold. “ the heart tree," Ned called it.
王国：In the south the last weirwoods had been cut down or burnt out a thousand years ago, except on the Isles of Faces where the green men kept their silent watch. Up here (指北境）it was different. Here every castle had its godswood, and every godswood had its heart tree, and every heart tree its face.
查了一下冰火维基，好像已经自己解答了，奔流城的红木林确实不是鱼梁木，但其中心依然有一棵鱼梁木的心树。看来说南方只有千面屿上才有鱼梁木应该是指生长在野外的鱼梁木，而没有包括一些大贵族家堡神木林内的心树。不过按照凯特琳的说法，应该不是所有南方大家族的神木林都是有心树并且上面刻有人脸的。
多谢6楼的解答，现在应该清楚了！
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