Is it considered "bad form" to mix wood of 2 different shades in an aquascape?

[ralliart12]

Basically, I have 2 sets of wood at my disposal; 1 set is a single, more "dramatic" & flexible piece of lighter shade, while the other set, is 4 pieces of darker shades. Was thinking of combining them in my next tank, but am concerned:

is it like an instant "demerit point" when wood of different shades of brown are mixed in a scape, i.e. when one mixes rocks from different types & shaes of colours together, the feeling of the scape is very un-homogeneous ?

The 2 different shades of brown can be seen in the photo below (I have 4 more moss-covered units of the type of wood on the right):

download.jpg

[Shadow]

You can use it if the whole surface of wood on the right covered by moss, no one can see what under it. if not then you can't