Estimating Tree Age when looking for older sites

[gitterdug]

I put this on the CTX forum (my native forum), but wanted to cross post to here, as it has some relevelance for several forums on the site.

One of the things I love to do, is hunt older sites, mainly in the country. Here in Texas around my particular area (DFW), we don't go past about 1850's. In the country, driving around, I am always on the lookout for old homesites. I watch along creeks for rocks, vegetation, remnants of log cabins, etc., but from a distance, the biggest thing I see most of the time, are the out of place trees, built into a row, or a square, or by nature of their species, out of place.

Have you ever wondered about how to determine the age of a tree in the field? We can guestimate.....oh, a big ol' oak tree is 150 years, or a thick mesquite tree is 75 years, etc.

I stumbled across the following information and thought it might be of some value to someone on here, if for nothing else, than to help narrow down a site's age.....circa 1930 vs circa 1850. So, I hope this helps someone. I have this on my iphone and use it sometimes.

Finally, how do you folks determine ages of vegetation?



The Tree Aging Formula

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) I use the Audubon Field Guides app for my iphone to determine species if I am not sure, and there are a lot of apps out there.

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. Let's use the hickory above to calculate age. A shagbark hickory's growth factor has been determined to be 7.5 and its diameter is 10 inches: 10 inch diameter X 7.5 growth factor = 75 years. Remember that the growth factors I provide are more accurate when taken for forest grown trees.

Growth Factors by Tree Species

Red Maple Species - 4.5 Growth Factor X diameter
Silver Maple Species - 3.0 Growth Factor X diameter
Sugar Maple Species - 5.0 Growth Factor X diameter
River Birch Species - 3.5 Growth Factor X diameter
White Birch Species - 5.0 Growth Factor X diameter
Shagbark Hickory Species - 7.5 Growth Factor X diameter
Green Ash Species - 4.0 Growth Factor X diameter
Black Walnut Species - 4.5 Growth Factor X diameter
Black Cherry Species - 5.0 Growth Factor X diameter
Red Oak Species - 4.0 Growth Factor X diameter
White Oak Species - 5.0 Growth Factor X diameter
Pin Oak Species - 3.0 Growth Factor X diameter
Basswood Species - 3.0 Growth Factor X diameter
American Elm Species - 4.0 Growth Factor X diameter
Ironwood Species - 7.0 Growth Factor X diameter
Cottonwood Species - 2.0 Growth Factor X diameter
Redbud Species - 7.0 Growth Factor
Dogwood Species - 7.0 Growth Factor X diameter
Aspen Species - 2.0 Growth Factor X diameter

Perhaps this is overkill for some folks, but when I am looking for that one special site to hunt, I want to know the site's age going in. At 60, in my overall physical health, I ain't diggin 9000 holes needlessly. I like the oldest sites I can get to, and though I don't always use this information, I do use it. LOL Chew the Cambium, spit the bark.

 

[bob.oz]

Here in Florida the big oak trees get my attention all the time....Driving down the street I always look at the old houses and when I see that big old oak...My thoughts and hunches are going a mile a minute.....In conversation with new acquaintances about MDing My first two questions are:How old is your house?....Any big old oaks?....Never saw a shade tree I didn't want to swing the coil under!......Good Info...Thanks...GL HH

 

[JimmyCT]

Interesting topic. I look for large trees that stick out in an area too. Anyone have an idea to what kind of tree this is? It has to be close to 26-28" diameter. It looks awful dead to me lol But I am interested to its age as it sits way out in the middle of the woods (took me about a half hour of walking in the woods to get to it) with a stone wall running right up against it. My senses tell me to check this place out. Right now it is too bug / tick infested but I am going to go back in the Fall and give the area a good sweeping.

 

[Bucksport]

Great info. Also look for big overgrown apple trees. Good indication of old home sites.

 

[ralph]

I'm no xpert but that looks like a Beech tree, they live long and getBig.

 

[GKMan]

looking at that tree made me want to take out my copy of Forest Forensics this is what he had to say about trees that looked like that.

 

[JimmyCT]

Gary - great information thank you!