Tallest & Largest redwoods .. Measuring

by Mario Vaden

 

This page has some measurements from some years back and links to a site that may update more frequently. The value in presenting older heights or diameters may be showing how much or little some redwoods changed over time. Review my Hyperion redwood page for extra information related to this. Also, researchers stopped using redwood names in reports from about 2012 and years after.

The measurements represent years invested by explorers like Atkins and Taylor and Dr. Sillett. Michael Taylor is shown below doing a measurement near Lost Man Creek close to Dog Soldier. Atkins and Sillett are in a photo near the end, preparing a laser measurement in Redwood National Park. Few people know the redwood forest like these men. My main redwood page should link to a page about each of them.

Gymnosperm Database may include and update measurements, Michael Taylor used to include regular updates but eventually quit landmarktrees.net and allowed his webiste to expire.

 

2011

Next, a tallest redwoods 2011 in meters. Source was Gymnosperm Database. Remember, this is old historic data now. The heights and order are not the same anymore. There were changes in order, plus gain or loss of height by 2013-2015.

Name, park, height in meters
Hyperion - Redwood 115.61
Helios - Redwood 114.58
Icarus - Redwood 113.14
Stratosphere Giant - Humboldt 113.05
National Geographic - Redwood 112.71
Orion - Redwood 112.63
Federation Giant Humboldt 112.62
Paradox - - Humboldt 112.51
Mendocino - Montgomery 112.32
Mellenium - Humboldt 111.92
Apex - Humboldt 111.83
Pipe Dream - Humboldt 111.71
Harry Cole - Humboldt 111.65
Rockefeller - Humbolt 111.59
Minaret - Humboldt 111.56
Alice Rhodes - Humboldt 111.53
Mother & Daughter - Humboldt 111.50
Lone Fern - Humboldt 111.47

Pre-dating 2000

Below, are redwood sizes pre-dating 2000: another snap shot in time. Abbreviations are parks: PCRST Prairie Creek Redwoods State Park, JSRSP Jedediah Smith Redwoods State Park, RNP Redwood National Park, H Humboldt or M Montgomery.

Plenty of changes have occurred in the big redwood arena since 2000. Remeasuring, and new discoveries..

The table will provide the height, the diameter at breast height / DBH, and the volume of the trunk and main stems in cubic feet. These trees have been discovered and measured by several people. Chris Atkins and Michael Taylor found the bulk of the tallest redwoods. Data below was the result of work by Chris Atkins, Michael Taylor, Robert Van Pelt, Steve Sillett and Ron Hildebrant.

advertisement

Measuring redwood trunks

A few common measurements for redwoods are diameter, height and trunk volume. This section is mainly about measuring diameter of huge redwood trees. Basically, redwood diameter is measured at DBH or diameter breast high: 4 feet & 6 inches above soil grade.

Image to the right: Chris Atkins and Professor Steve Sillett setting a tripod to measure redwood height with a laser rangefinder in Redwood National Park. Equipment like this allows researchers to measure several redwoods per day.

The way redwoods are measured for research can differ from how trees are measured for nomination as national champions. American Forest champions are based on points for height, girth and canopy width added together. Scientists studying redwoods want to know more, like how many cubic feet of wood the trunk and stems have: the real measure of how big it is.

Estimate 4 ft. & 6 in. up the trunk and measure diameter there, extending a tape horizontally around the bole. Include indented areas of the trunk. In other words, don't press the tape inward against the bark at every recessed spot. If the ground is sloped, average where the trunk meets the high side and low side, going up 4 ft & 6 in. for each and splitting the difference. Average it.

In part, diameter is opinon because a decision has to be made about where soil grade is. Twigs and leaves do not count as soil.

Some experts who are adept with instuments can measure irregular trunk bases rather meticulously to determine wood volume and shape, sometimes referred to as the footprint on the forest floor.

Because some trunks are eliptical, measure the full circumference and do the math. Stick with the average. Example for redwood with 70' circumference: 70' divided by 3.14. The answer is 22.29' diameter.

Many giant redwoods have lower trunks like volcanoes. It helps to stand back from the redwoods and take a look from a distance. Stand 20 or 30 feet away and look around for the average soil level.

Diameter measuring can be more complicated, but those basics are adquate for most people. If a redwood or conifer trunk branches-out up into multiple stems below the DBH height, then only the largest stem may be measured. That is how the champion point system works. And that can be a failure to judge on the true size. That's one rule of one system. If there is a burl, some experts move the tape above it.

Beginners .. estimate 4.5' above the average soil grade, measure circumference, and divide by 3.14. For convenience, use the automatic conversion table on this page to convert diameter, circumference and area. Fill out one field, and the others should be generated for you. Enter numbers whole or as decimals like 5.6 if you wish.

For height, if the page remains, read the following:

http://www.americanforests.org/resources/bigtrees/measure.php