Formula for calculating moisture content?

[jph]

 I have been using the formula:
Moisture content = weight of water in wood divided by oven dry weight  times 100.
The weight of water being initial weight minus oven dry weight.

mc = (initial wt - oven dry wt) /oven dry wt * 100

My latest sample was a piece of Grand fir straight of the mill weighing 187 gm. It now weighs 77 gm.

therefore  mc =(187-77)*100/77  = 142%   ??? ???

What am I doing wrong?  Does not a mc of 100% mean it is  all water?
Am I just being stupid?
John

[Don P]

You're right, its just real green. Its 142% heavier than oven dry. Yellow pine can be 3 times heavier green than dry.

[jimF]

No,100% does not mean it is all water.  You are comparing the amount of water to the amount of dry wood.
Most of the time in life when we use percent, we are compareing a part of the object to the whole object.  With MC we are comparing one part to another part.  When we have more of the first part than the part we are comparing it to, we get a percentage that is greater than 100%.  In your example, you have more water than dry wood and you get greater than 100%