rpart: how to remove the "long" labels

Question

I am wondering is there any way that I can remove the (long) labels in my tree. For example, in the following tree I would not to remove the label for the branch #6 i.e. Clarity =l1,Sl2,Sl1,VS2

library(rpart.plot)
library(rpart)
data(diamonds)

    fit <- rpart(price ~ carat + cut + clarity, diamonds, method = "anova")
    rpart.plot(fit, type = 2, nn=T, extra = 101) 

FYI, in reality in my data the label of one branch is ID and it goes from one side of the image to the other! That's why I want to find a way to only not show the label but the tree would stay!

Any help with explanation is highly appreciated.