In the 'noise' tab of a power fractal node you'll find 3 input fields at the bottom, each containing the number '1'. These fields relate to the X,Y and Z axis of the shader, in that order. In TG, X is left/right, Y is up/down and Z is back/forth, when looking North, or towards 0 degrees on the compass.
If you want to stretch the fractal noise on the horizontal you would raise number in the X and/or Z fields. Entering '2' will effectively double the stretch of the noise along whatever direction/s you choose, using '10' will stretch the scale x10 in that direction. Putting a smaller number i.e. '0.1' in any field will shrink the scale of the noise in that direction.
Either enter 'X=10, Y=1, Z=10' to stretch the noise x10 on the horizontal, or enter 'X=1, Y=0.1, Z=1' to shrink the vertical noise scale. If you use the second method, you'll need then to multiply the 'scale tab' entries of the fractal by 10 to get the same effect as the former method.
I think it is best(easiest) to use a normal scaled fractal and raise the horizontal parameters to stretch the fractal. Both ways do the same thing but it's easier to understand your fractal scales in the first tab being stretched, rather than shrunk and then having to compensate by raising the original scales.
