Extract a subset of tree from random forest model

Question

From Liaw's classification and regression by RF paper, "The best way to determine how many trees are necessary is to compare predictions made by a forest to predictions made by a subset of forest"

I am wondering if there is a way to extract subtree for prediction with R's randomForest package. getTree seems to print out the structure. Any suggestion would be greatly appreciated.

Answer 1

Try this one in randomForest, predict(rf, dat, predict.all=TRUE), you can get predictions from all the sub trees.