Wood in general isn't very good mareial for DNA extraction. In general wood consist very small quantities of DNA, because cells in wood are without any life content (such as protoplast in general). In this way you must to try such methods that will able to extract the significant quantity of DNA.

Anoter aspect of DNA isolation from wood is low quality of isolated DNA in general, especially long fragments.

You may to try at first some standard protocols, for exaple Doyle and Doyle, 1987. Such protocols are easy to apply and the quantity of your samles material can be vary widely.

Another way is to use commercial kits for this isolation. Nowadays we have very wide range of different kits and you can to choose some of them depend on their properties and availability in your region

What do you mean by "wood"?

Best wishes

i have, in the past, extracted DNA from woody roots by first grinding them into a powder with a mortar and pestle in liquid nitrogen. I then used a qiagen DNeasy kit to prep the DNA and a Mo Bio Power Clean DNA clean-up kit to remove the PCR inhibiting contaminants.

good luck!

-val

I am struggling with the same problem, extracting DNA from wood samples (bark). I have extracted a few times and both the quality and quantity is not good. I have concentrated the DNA before hand but it seems that the quality goes down further. If you have had success please share or should we just try a clean up kit?

Though, I am struggling myself these days to get DNA extracted. I think the following article could be valuable. 

Please keep updating about this. Thanks 

I'm towards the end of a project involving DNA extraction from wood. I've reviewed alot of literature on the subject and can say that the most common method is grinding the wood on Liquid Nitrogen with a follow on of any of the CTAB choroform methods.

Also it's fairly apparent from the literature and my experience, that sound wood, especially heart wood has very little DNA.

I just trialed several kits, combined with grinding liquid nitrogen. Of the Qiagen plant pro kit, the Qiagen plant mini kit, and the Qiagen biofilm kit, only the biofilm kit extracted any DNA from sound wood, and it was very little.