Age of trees

[Kenneth in Texas]

Is counting the rings actually accurate in determining a trees age and whats it mean if some are close and some are far apart?

 

[fordmantpw]

Well, counting rings is what the experts use to determine the age of trees, so I would say that it is accurate.

Closer rings means the tree didn't grow as much that year, whereas rings further apart means the tree grew quickly. This is typically due to rainfall. Years with plenty rainfall will space the rings out further. You can learn a tremendous amount about a tree and the weather in that tree's life by studying it's rings. Supposedly, you can pinpoint times when there were fires and other disasters as well. It's really pretty cool.

 

[Silvic]

When a tree or stand of trees are suppressed the rings will also be very close together since they are not growing very robustly. You can acquire a coring tool and do an analysis without even cutting down the tree. Dendrology I will not comment on the subject of the site just using it as an example.

 

[SandburRanch]

Here is an example that one of my kids made as a project at the ranch over 30 years ago when quarter sawed lumber was available. It looks as if it was cut and milled at an age of at least 60. We just don't know how many rings were cut off in the process of making this a 1x10. My eyes aren't too good but with a magnifier it may have had at least 10 consecutive years of severe drought but we just don't have enough information of its history to determine when those 10 years were.

 

[oosik]

When I cut trees for firewood - I would count the rings. I cut some ponderosa pine that were over 125 years old and 36" on the butt. I cut firewood here for ten years and then went to pellets. In all the trees I cut there was an obvious severe drought during the mid-1930's to mid-1940's. I wish I knew more about dendrology because many of the old, large stumps still exist here on the property.

 

[3930dave]

Under the right conditions, small trees can be surprisingly old.

Some of the small scrub evergreens were studied on the side of the Niagara Escarpment, west of Toronto. I don't recall the exact #, but it was several hundreds of years (500+ ?) for a tree just a couple of feet high. Pretty much needed a microscope to count those rings.

Rgds, D.

 

[MossRoad]

Is counting the rings actually accurate in determining a trees age and whats it mean if some are close and some are far apart?

I planted several thousand trees back in 1989. I'll let you know around 2045 if its accurate! :laughing:

 

[SPIKER]

I planted several thousand trees back in 1989. I'll let you know around 2045 if its accurate! :laughing:

Mine were planted in 2003 well over 5000 of them...

Yes very accurate IF you can read the lines. The OLDEST trees are in CA (look up Methuselah, bristlecone pines and OLD trees.)

Mark

 

[dave1949]

Besides growing conditions for the year of the ring, the spacing also can show physical stresses on the trunk. You can have rings that are wide on one side of the tree and narrow on the opposite side.

 

[Silvic]

Just thought I would throw this one out as an example of a tree that was very suppressed for the first part of it's life then started to thrive. Lots of stress in the wood but the growth can be seen with the change between 40 and 42 years of age.

 

[Pilot]

Great answers and correct info, but the one thing not mentioned is the ring count show the age of the portion of the tree at the height where you are counting, i.e., if you bore the tree at 5 feet and it typically takes 4 years to reach 5 ft. tall, add 4 yrs. to the ring count.

 

[Buggs67]

Great answers and correct info, but the one thing not mentioned is the ring count show the age of the portion of the tree at the height where you are counting, i.e., if you bore the tree at 5 feet and it typically takes 4 years to reach 5 ft. tall, add 4 yrs. to the ring count.

I hadn't realized that. Also relevant is that certain trees, hardwoods, always have thinner rings than other softer trees. And I think that the rings in the earlier years of growth are always thinner than later years. I only count the rings in big trees. I had two red oaks fall during Hurricane Irene, one 94' tall, the other 97'. They were 105 years old IIRC.

 

[JerryK]

Insects can effect ring width, too. We had forest tent caterpillars real bad in our sugar maples about four years ago. Trees lost most of their foliage mid summer.... sounded like rain walking thru the big maples from all the guano raining down.....

 

[PILOON]

Doing some landscaping I needed to remove an old cedar stump.
I sliced off a section of a main root to make an interesting serving platter.
I meticulously counted the growth rings to determine that it was 186 years old. (at least that root was)
Either that was a red cedar or a by the coloring a BC fir but then we are not on the west coast.
My nose definitely identified a cedar like aroma.

 

[tractchores]

I'm always amazed at the age of some of the trees on my property. We had a big oak blow down and it had over 200 rings! I always think long and hard before felling a tree unless its damaged or otherwise causing some big issue because there will never be another mature tree there in my lifetime. Obviously if you're managing for Timber its a little different discussion.

I read this book: Exploring Stone Walls: A Field Guide to New England's Stone Walls: Robert M. Thorson: 9780802777089: Amazon.com: Books which discusses how you can tell the history of the land by stone walls. It also talks about how to read a forest and how you can tell the history of a forest by looking at the size of trees, branching patterns and the forest floor including fallen trees. Its pretty interesting and gives an idea of what it might have been like when these old trees started growing.

 

[jrclark]

I'm always amazed at the age of some of the trees on my property. We had a big oak blow down and it had over 200 rings! I always think long and hard before felling a tree unless its damaged or otherwise causing some big issue because there will never be another mature tree there in my lifetime. Obviously if you're managing for Timber its a little different discussion. I read this book: Exploring Stone Walls: A Field Guide to New England's Stone Walls: Robert M. Thorson: 9780802777089: Amazon.com: Books which discusses how you can tell the history of the land by stone walls. It also talks about how to read a forest and how you can tell the history of a forest by looking at the size of trees, branching patterns and the forest floor including fallen trees. Its pretty interesting and gives an idea of what it might have been like when these old trees started growing.

Thanks for the book reference. I'll have to check it out.

Our property is entirely wooded and has a host of old stone walls that used to separate the various fields. Now that the forest has taken over those fields for the past 100-150 years, they've given it a truly ancient look. The deer love to follow them as well!

There's one tree in particular that is massive and very ancient looking in comparison to the surrounding trees. He's a great old white oak with a huge canopy. Love that tree! We're guessing he predates many of the farms, probably one of the shade trees left to stand.

 

[Jstpssng]

I believe that it was mentioned before... but the width of the growth ring shows how fast the tree grew at that age. If you've had your land for a while and remove a tree next to the stump of another which you cut years ago, you can see the difference.

Last winter I was driving past the University Forest of my Alma Mater... the student timber harvesting crew had brought some aspen veneer out to roadside. Just to be a smart ***** I stopped, counted growth rings back to the year that I graduated; circled that ring with a lumber crayon and wrote "Class of 1980" ;-)

T h e tree had grown about 15" in diameter... from pulpwood to veneer.
:thumbsup:

 

[/pine]

FWIW...

Direct reading of tree ring chronologies is a learned science, for several reasons. First, contrary to the single ring per year paradigm, alternating poor and favorable conditions, such as mid-summer droughts, can result in several rings forming in a given year. In addition, particular tree species may present "missing rings", and this influences the selection of trees for study of long time spans. For instance, missing rings are rare in oak and elm trees.[3]

Wikwpedia...

 

[clemsonfor]

Besides growing conditions for the year of the ring, the spacing also can show physical stresses on the trunk. You can have rings that are wide on one side of the tree and narrow on the opposite side.

This is called compression wood or tension wood.

Ring counting is accturate, but you need to know that there is eary wood and late wood. so there is one dark ring and one light ring per year. One is put on in the growing season and the other during the dormant season. this is more noticeable in larger rings. Some trees is hard or next to impossible to see rings in some trees in others they show up well. A tree that its hard is Poplar down here. Rings are usually larger when a treee is young and growing faster, when trees get older they slow down. This changes depending upon the species of tree. Sy for example certain oak trees and conifers are extremely long lived but some fruit type trees have a very short life span. Ring width can also be small due to dry years or stresses like too much pruned off of it by man or nature, insect infestation or over crowding by other trees.

There can also be false rings, these happen when you have a very wet spring and a dry first part of summer and then a very wet end of summer.

 

[clemsonfor]

I hadn't realized that. Also relevant is that certain trees, hardwoods, always have thinner rings than other softer trees. And I think that the rings in the earlier years of growth are always thinner than later years. I only count the rings in big trees. I had two red oaks fall during Hurricane Irene, one 94' tall, the other 97'. They were 105 years old IIRC.

This is not true. Some hardwoods yes others no. A Cottonwood, Populus Deltoideus (spelling??) will have way bigger rings under normal growing condidtions than out common loblolly pine (not the 5th gen seedlings or clones or anything). Water oaks can have 1/2' rings early on as well whcich is similar to our pines here as well, Poplar and sweetgum similar growing pattern.

And also rings under normal conditions should almost always at least in my region will be BIGGER early on in life. The only exception is say if that tree started life in a supressed situation and was in the under story and it took 20 years or so to get the height or waiting on a tree near it to be cut down or die to allow it light to grow and flourish. If were talking open grown trees where they get all the light they need for growth they will be bigger early on.

And yes i do know what i am talking about. I am a professional forester. For reference so that it will give some credibility to what i said.