A tree with a 10 to 15 inch diameter typically weighs between 45 and 55 pounds; however, the weight of living trees can vary widely between 1000 pounds to about 2,000,000 pounds.
This is general weight is very broad because it depends on many variables.
Some of these variables are: density, volume, the height and diameter of the tree, the type of wood (hardwood vs. softwood), and whether the tree is alive and has leaves.
We will also explain how the tree type and age contributes greatly to the overall weight.
What can you expect. First, we will go into a discussion about how all of these factors contribute to the weight of a tree, and how to calculate tree weights.
Height
Height is the number one thing that directly impacts the weight of a tree.
Most of the time, taller trees weigh more than shorter trees.
For example – 80-foot tall hardwood trees (which are very heavy) weigh 18,000 pounds more than 50-foot tall pine trees (which are lighter).
However, this is not always true. Short trees that are wider in girth weigh far more than taller trees that are not as wide.
Height is easy to measure to calculate the approximate weight of a tree, if you are using the right tool.
Diameter
One of the biggest factors that affects tree weight is the diameter. Diameter is directly related to weight.
A corollary to this would be that as the diameter of the tree gets larger, the weight increases.
For example, a hardwood tree of 12 inches in diameter and average height will weigh around 1,500 pounds, while a hardwood tree of 26 inches in diameter and average height weighs 8,400 pounds, which is nearly triple the weight.
In just looking at two trees, you can tell which one has the larger cross-section.
You can guesstimate the tree diameter, as well as measure it. Knowing the diameter of the tree will help you estimate the total weight.
To get the diameter of the tree, you have to find the circumference at breast height.
Breast height is normally around 55 inches off the ground, and the circumference is the complete half-moon length around the tree.
These are general numbers to go by, but each species of tree will have varying measurements. Generally speaking, you will take the measurement of the circumference to find the diameter.
Volume
The relationship is directly proportional between the tree’s volume and its weight: as one increases, so does the other.
This means volume plays a direct role in determining a tree’s weight. Also, volume is the major factor in determining tree weight calculation.
However, since there is virtually no way to estimate the volume of a tree, calculating it is equally as difficult as calculating tree weight.
You can estimate a tree’s volume based on:
- its species,
- its age, and
- its growth location
A tree guide or a forester will help provide you a better estimate.
Hardwood Vs. Softwood
The type of wood found within a tree contributes to its total weight:
- The general rule of thumb is hardwood trees tend to weigh more than softwoods. A hardwood tree is one that matures seeds that have a covering that has the potential to grow into fruits or nuts.
- A softwood tree matures seeds with no covering that simply drop to the ground and do not have the potential to grow into seeds or nuts.
The reason hardwoods weigh more than softwoods is that their make-up simply makes them denser.
For example, beech trees, which are hardwood trees, weigh approximately 45 pounds per cubic foot in comparison to cypress trees, which are softwood trees, weighing in at 32 pounds per cubic foot.
This weight difference is relatively obvious, but remember that this weight is not just made up of one factor.
All the factors you are now aware of culminate in the total weight of a tree.
Density
In the earlier section, we discussed density.
Tree density is defined as the percentage of ground area occupied by the tree when growing in an area.
Density estimates can be used to estimate the biomass of a tree. Tree density is most commonly calculated based on canopy cover.
Again density is directly proportional to weight, so trees with a greater density are typically heavier. Measuring tree density will help you estimate potential weight of a tree.
Leaves
You might not think that leaves play a huge role in tree weight.
However, they are in fact the key components impacting tree weight.
Leaves contribute tremendous weight to the tree. You would also want to consider the type of leaves, and the quantity of leaves.
Larger Leaves – Like that of the banana and coconut tree – carry more weight than trees which have many small leaves.
There are also the opposite circumstances – like magnolia trees – which also carry a large leaf weight that contributes to the overall tree weight.
Species
The above features and the species impact on tree weight is what we have been building towards.
All of these traits remember will vary by species.
Each trait can vary greatly from species to species and therefore, can vary their expressiveness of weight. Density and height might even be in conflict for traits.
The way tree weight is measured is extremely complicated and involves many traits interacting together.
However, extremes have been recorded.
Fun Fact: The heaviest tree in the world is Giant Sequoia – weighs 6,167 tons and measures 1,487 cubic meters volume and over 300 feet in height.
There is no recorded lightest tree in the world, but the Balsa Tree is the lightest tree known since it has the lightest and softest commercially sold wood.
Calculate the weight of a tree using this formula
Calculating the weight of a tree requires the consideration of a variety of factors, including its species, size, density, and moisture content. It’s not simple to assign one formula to find this weight. However, here are a couple of formulas that can be applied to find a tree weight under different circumstances:
If you know the tree’s volume in cubic meters and its wood density, you can use the following formula to find the weight:
Weight = Volume * Density
For example, if a tree has a volume of 0.25 m3, and has a wood density of 700 kg/m3, its weight would be:
Weight = 0.25 * 700 = 175 kg
If you happen to know the diameter at breast height, or DBH, of a tree, along with the height of the tree, you can use the following formula to guess the weight.
Weight = (0.35 * DBH^2 * Height) / 100
This formula would assume a uniform mass, and a tree with a cylindrical shape. You will measure the DBH in centimeters (cm) and the height in meters (m).
For example, if a tree has a DBH of 50 cm and is 20 m tall, you would calculate the weight like so:
Weight = (0.35 * 50^2 * 20) / 100 = 8750 kg
If you have access to a scale to weigh each kind of material (age, leaf mass, branch mass, and stem mass), you can always add
Final Thoughts
There is no standardized weight for trees. Only averages are calculated based on a variety of factors and species, but there is no absolute tree weight.
Understanding tree weight is useful for a variety of reasons.
It may be useful for establishing biomass, usability, transportation and ecosystem.
Professional foresters and botanists generally compile and keep accounts of tree weight by species.