Question
I am a surveyor working near Three Rivers, Texas and just off of the Atascosa River. We have located a very old tree stump and trying to determine if the tree was a Cottonwood tree. I am not very familiar with Cottonwood trees and we do not have any leaves. This is an old stump. If we take pictures do you think you could help us identify the tree?

Also, how would you recommend the best way that we can identify the approximate age of this tree. We are trying to determine if this tree existed as far back as 1835. The tree is located in Live Oak County, Texas and near the Atascosa River.

We would greatly appreciate your help.

Respectfully Submitted,

Allen

Answer
Here is a general rule for stumps. Begin by determining the tree species and taking a diameter measurement (or circumference measurement) using a tape measure at Diameter Breast Height or 4.5 feet above stump level. If you are using circumference, you will need to make this calculation to determine the tree diameter: Diameter = Circumference divided by 3.14 (pi) For stumps add about five years since you can not measure at 4 1/2 feet.

Then calculate the age of the tree by multiplying the tree's diameter by its growth factor (see below): Diameter X Growth Factor = Approximate Tree Age.The Growth  factor for cottonwood is 2.
Example if the stump is 40 inches in diameter than the age is close to 85. (40X2+5=85)