ArtsAutosBooksBusinessEducationEntertainmentFamilyFashionFoodGamesGenderHealthHolidaysHomeHubPagesPersonal FinancePetsPoliticsReligionSportsTechnologyTravel

How to Tell a Tree's Age

Updated on January 22, 2018
Ancient Oak Tree at Folly Farm From the dimensions around its girth, the age of this tree has been estimated to be greater than 300 years.
Ancient Oak Tree at Folly Farm From the dimensions around its girth, the age of this tree has been estimated to be greater than 300 years. | Source

Why Ageing Trees Is Important

Trees perform a wide variety of vital functions on earth, contributing to a habitable biosphere for all other living things. Among other functions, trees are vital for:

  1. Contributing significantly to the earth's oxygen supply.
  2. They have the ability to absorb, and therefore remove from wider circulation, a number of toxins and pollutants.
  3. Trees can be blockades for unwanted noise and thus reduce noise pollution when planted strategically around your home or neighborhood.
  4. They can slow down storm water runoff, encouraging the recharging of ground water aquifers.
  5. Because they are carbon sinks, absorbing vast amounts of carbon dioxide during photosynthesis, they contribute to the removal of this green house gas from the atmosphere.
  6. Trees cleanse the air of particulates, shade and cool even on a global scale and provide windbreaks.

Understanding the age of individual trees is important for a number of reasons. Foresters use tree age data to determine:

  • age of a stand of trees
  • how quickly the trees are growing (can be extrapolated by width of individual rings)
  • the health of individual trees which is also important for urban areas where unhealthy trees suffering from internal rot could pose dangers during storms or high wind periods.
  • a site index which provides a relative measurement of the quality of that particular forest site based on the average height of dominant tree species taken at a specified age;
  • this site index helps predict future returns from this site with respect to tree harvesting and also provides a means of predicting the land productivity for both trees and wildlife
  • core samples from trees can also be used to reconstruct past climate and events
  • trees used in historically significant structures and art can be dated using techniques employed by dendrologists

Tree Growth And Age

Click thumbnail to view full-size
Illustration of a Sequoia sempervirens in sectional viewDiagram of Xylem and Phloem in a stem. 1. Xylem 2. Phloem 3. Cambium 4. Pith 5. Companion Cells
Illustration of a Sequoia sempervirens in sectional view
Illustration of a Sequoia sempervirens in sectional view | Source
Diagram of Xylem and Phloem in a stem. 1. Xylem 2. Phloem 3. Cambium 4. Pith 5. Companion Cells
Diagram of Xylem and Phloem in a stem. 1. Xylem 2. Phloem 3. Cambium 4. Pith 5. Companion Cells | Source

How A Tree Grows Can Be Used To Determine Its Age

Only 1% of a tree is actually living tissue. Just under the bark is a thin layer of living cells called the cambium. Other living cells are found in the roots, the growing tip, buds and leaves. In terms of determining tree age, the tree trunk is the key.

  • The cambium produces phloem cells, which transport food from leaves down to the roots, closest to the bark on its outside layer
  • The cambium also produces xylem cells, which transport water and nutrients from roots to leaves, on its inside layer.
  • Phloem continues to live for the life of the plant while xylem in trees lives only one season.
  • The dead xylem forms the woody support structure of a tree.

Each year's growth of xylem provides:

  • one light ring representing early spring growth with thin-walled large cells adapted for transport of large water quantities
  • and one dark ring in the summer composed of thicker walled cells adapted for strength for supporting the abundant new growth from the spring and summer.

Tree Measurement Methods

Click thumbnail to view full-size
Tree rings, Hillsborough forest. Well-defined rings on one of the logs. Drill to take samples for dendrochronology from trees
Tree rings, Hillsborough forest. Well-defined rings on one of the logs.
Tree rings, Hillsborough forest. Well-defined rings on one of the logs. | Source
 Drill to take samples for dendrochronology from trees
Drill to take samples for dendrochronology from trees | Source

How To Find Out The Age Of A Tree

1. You can tell how old a tree is by counting the pattern of dark and light rings in the tree trunk. One light ring plus the neighboring dark ring constitute one year of growth for the tree.

  • This method works well for dead trees.
  • It can also be accomplished by the utilization of an increment borer. This borer needs to be longer than the radius of the tree. The borer takes a core sample to the pith in the middle of the trunk. Tree rings can be counted in this core sample and the tree is not permanently damaged.

2. It is still possible to closely estimate the age of a tree without counting rings. Knowing the species of tree and the tree's circumference will allow for a fairly accurate determination of age.

  • Determine the correct species of tree.
  • Wrap a tape measure around the tree trunk about 4½ feet above the ground, measuring the circumference of the trunk in inches.
  • Multiply the tree's circumference by 3.14 to determine the tree's diameter in inches.
  • In the chart below, find your tree's growth factor and multiply it by the tree's diameter.

Dendrology: The Art of Estimating Tree Age

Growth Factors For Various Forest Grown Trees

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

Resources Used

Nix, Steve. About.com Forestry. Using the Annual Tree Ring to Determine Tree Age, 2012.

Journey North. Signs of the Seasons. How Old is Your Tree?. 2012

Royal Forestry Society. Tree Biology. How Trees Grow. 2012

For a sugar maple:

Step 1: circumference=5 feet 4 inches

Step 2: its diameter=64 inches / 3.14 = 20.4 inches

Step 3: 5.0 (growth factor)x 20.4 inches (diameter) = 102

Therefore, this sugar maple is about 102 years old.


working

This website uses cookies

As a user in the EEA, your approval is needed on a few things. To provide a better website experience, hubpages.com uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at: https://corp.maven.io/privacy-policy

Show Details
Necessary
HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
LoginThis is necessary to sign in to the HubPages Service.
Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
AkismetThis is used to detect comment spam. (Privacy Policy)
HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the googleapis.com or gstatic.com domains, for performance and efficiency reasons. (Privacy Policy)
Features
Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
MavenThis supports the Maven widget and search functionality. (Privacy Policy)
Marketing
Google AdSenseThis is an ad network. (Privacy Policy)
Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
Index ExchangeThis is an ad network. (Privacy Policy)
SovrnThis is an ad network. (Privacy Policy)
Facebook AdsThis is an ad network. (Privacy Policy)
Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
AppNexusThis is an ad network. (Privacy Policy)
OpenxThis is an ad network. (Privacy Policy)
Rubicon ProjectThis is an ad network. (Privacy Policy)
TripleLiftThis is an ad network. (Privacy Policy)
Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
Statistics
Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)
ClickscoThis is a data management platform studying reader behavior (Privacy Policy)