Textures of Wood, which was cut along the log of a tree, can be rendered with this function. Vertical stripes, distorted by a variable noise, are devoted to fill a range from smooth to rough wood shades.

With raising Octaves values, more details are added to the wood pattern. The valence of these details, in relation to the greater features, is controlled with the Persistence value. Roughen the wood texture by increasing the Resolution regulator, but the overall features size will decrease.

The number of stripes can be increased with the Horizontal parameter. The Vertical value only affects the turbulence in vertical direction, because only vertical stripes are rendered by this function.

Manipulate the turbulence amplitude with the Amplify value. Higher values result in greater distortions (compare Image 1 to Image 2).

Tip: Texture Maker's Resampler module is very helpful to create natural patterns like wood. Have a look at it.