Is there a formula more popular in the tropical regions than Hoppus? Many would say no, so we’re here to understand about this particular formula.
The traditional system of measure became famous in 1736 by Edward Hoppus and became widely used in the UK and their colonies. Nowadays, Hoppus is still used in Asia, Africa, and South America, especially for hardwood.
It’s known that the Hoppus system was created to measure the real usable volume of timber, so, similarly, as JAS, it tries to square the log and exclude the parts that won’t be used by the industry. Hoppus results give 78,54% of the Hubber cubic meter for the same log dimensions, which shows the industry professionals these results as actually lumber material. However, in modern sawmills, these results are just an approximation, and the Hoppus formula lost its spot and became more of an example of how the useful volume of a log could be calculated a couple of centuries ago.
Hoppus is measured both in imperial and metric units. The results are expressed in a unit called Hoppus ton, which is, in fact, a unit of volume and not a unit of weight and can be very confusing as a term. It’s also known that the Hoppus ton is one of the most traditional units of volume in forestry.
Moreover, this is equal to 50 hoppus feet or 1.8027 cubic meters and is still used by trading valuable tropical hardwood. The fact that the Hoppus ton weighs way more than a regular ton is also a cause of confusion in the industry, except when measuring very low-density species or dried logs.
Regarding Hoppus, it’s important to point out the different types of measurement: via girth and diameter.
To get the results for volumetric imperial measurements, the following formulas are used:
Hoppus ft³ via diameter = mid-diameter in inches² x length in feet x 0,004283 – rounded to the nearest tenth ft³
Hoppus ft³ via girth = (mid-girth in inches / 4)² x length in feet / 144 – rounded to the nearest tenth ft³
To determine the volume using metric measurements, the following formulae are used:
Hoppus m³ via diameter = mid-diameter in cm² x length in meters x 0,000061685 – rounded to the three decimal points
Hoppus m³ via girth = (mid-girth in cm / 4)² x length in meters / 10,000 – rounded to three decimal points.
For general considerations, the girth is generally used for the volume measurement, but there’s also a way to get results from diameters. Also, we must point that both under and over the bark measurements are made with Hoppus, mainly depending on commercial reasons are specific regions of the world (notably, the northern part of South America uses under the bark while some Asian countries are still getting over the bark results).
In conclusion, we understand that Hoppus is still primarily used today, but is still a method that didn’t go through the changes of the 21st century, causing commercial disputes by different grasping of the formula itself and its denominations – for example, the so-called Hoppus ton which actually measures volume, not weight.
We want to know from our forestry professionals: what could be the solution for standardizing the log measurements and make trading easier and more efficient?
