Here's a great way of making different types of wood textures without killing a single tree.

You might think that creating realistic wood in photoshop is an impossible task, but the truth is that it is quite a straight forward procedure.

Crtl+N to open a new document and give it a nice big size.



Press 'D' on the keyboard to reset the colours then click the foreground colour. When the colour picker screen appears, choose a colour similar to this:



You can see that I have chosen the 'custom' button. This lets you choose from several different color books. You can just as easily choose a color from the 'picker' screen.

Now do the same with the background:




Notice the difference in colors! Go to Filter>Render>Clouds...



...to achieve this result:



Now we need to go to Filter>Distort>Polar Coordinates.



Remember to click Polar to Rectangular:



And we end up with something like this:



Now go to Filter>Noise>Add Noise



and give it about an 8%.






Then Filter>Blur>Motion Blur



with these values:



That should leave you with something like this:



Click the new layer icon (cicled red) and a new layer will appear above the first.



Choose a slightly darker foreground colour.



Now a more difficult bit. Select the Marquee Tool (M on the keyboard and make a thin selection across the width of the image like so:



Now we need to go Edit->Fill and choose 'Foreground color' from the drop down menu. You should have something like this:



Repeat the same procedure using the marquee tool to create different line thicknesses: To save time you can hold down the shift key while you are making the selections. Then you only have to do the Fill once.



Now we are going to add a wave effect:



...using these values.



Which should give us a result like this:



We don't need two different layers now so press CRTL+E to merge them:



Let's add another Noise effect:



And another motion blur effect:



Right. it's time to 'bring the wood to life'. Press CRTL+M to open the Curves window:




By clicking on the vertical line and moving the point up like so we can the wood texture completely:




By adding another we get a pine texture.



A couple more and the result is a deep, rich wood:



Feel free to experiment here. This was I liked the best:



Now copy the layer by dragging it over the new layer icon:



Change the blending mode to Screen:




Of course, you don't have to use Screen mode. Try other alternatives like Multiply, Vivid light or Overlay. Experiment and have fun!