Why horizontal bars instead of a line

Hey list!


It looks simple, though it's not possible for me to plot the following
properly:

(some made-up data)

GrSe    Clone1  Clone2  Clone3  Clone4  Clone...
G1999   2       3       6       5
G2000   2       5       7       4
G2001   5       3       7       3
G2002   4       5       8       3
G...



GrSe=Growing Season.

I've read the file as "x" and then tried:        plot(x$GrSe,x$Clone1)

The output is 4 horizontal bars. Even if I write
plot(x$GrSe,x$Clone1,type="n") R is still plotting!
I figured already that if I delete the "G" in front of the years it'll
work, however, I'd like to keep the "G".
Is that possible?

Hope it is an appropriate question for the list.

Thanks,
Stefan