Hello,
If the bog wood you have has not been pre soaked it will leach tannins when you put it in your tank, this will turn the water a tea like color. If you want to help prevent this happen you can soak the wood in a bucket of very hot water, change the water when it cools down for more hot water. The more times you do this the more tannins you will remove from the wood before you put it in your tank.
If you don't mind the tannins leaching in your water (tannins wont bother the fish at all) just give the wood a good scrub under some water to remove any loose bits which will otherwise float about in your tank when the detach themselves.