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Timber Cruising and Cable Logging in North Vancouver

ellinor dobie 125

ellinor dobie 125When ICF Student member Ellinor Dobie was awarded the 2016 Prince of Wales Forest Leadership award, it was the beginning of a once-in-a-lifetime placement at Strategic Natural Resource Consultants in British Columbia, Canada. In her first guest blog, Ellinor describes her unique new surroundings and getting fit in the forest while timber cruising and checking deflection lines for cable logging.


The forests here in North Vancouver Island are harmoniously diverse: Amabilis fir (balsam), Western hemlock, mountain hemlock, Western red cedar, and yellow cedar flourish together productively and regenerate profusely. Inside this varied forest one encounters a steep tumble of downed stems, tangled undergrowth, blood-sucking insects, rock bluffs, slippery streams, and a shroud of gentle drizzle. An exciting and exhilarating challenge, especially when tackled with the friendly, lively, tough and alarmingly fit foresters who work here. And when I pause to catch my breath, the sheer beauty and verdance of it all far outweighs my current tally of 21 cuts, 24 bruises and numerous insect bites.

I am experiencing this landscape through the lens of working with Strategic Natural Resource Consultants, a company that provides a range of forestry-related services to many different enterprises. The general atmosphere is a confident mix of camaraderie, professionalism, and determination. Friendliness, warmth, and welcome greeted me from the moment I walked in the office and have continued throughout my time here, not just in work hours but in many adventures during the evenings and weekends.

Timber Cruising

The majority of the past three weeks I have spent out with the timber cruising team, learning about and aiding them in their task of evaluating the timber in a block.

The Big Picture…

The forest is an unbroken blanket here, and most of this is “Crown Land” – meaning that it is owned by the government. Private companies buy the rights to log this land. With the rights to the timber also comes the responsibility to pay stumpage and ensure restocking (through planting or natural regeneration). Stumpage is a tax, based on the value of the timber in the block, and is the way in which companies pay for their use of the land. Timber cruisers are employed by the company to determine the value of the block: the higher the value the higher the stumpage. As the company has a vested interest in the outcome, the cruisers must be from an independent organisation (such as Strategic), and the work will be audited by the government.

The Method

The aim of the game is to gather unbiased and detailed information on the average diameter (dbh), height, timber quality, and slope of the forest. Plots are laid out on an 100m x 100m grid, and you travel between them using a compass and Vertex to check your bearing and distance. The plot centre must be within 2m of the true location, so no option of going around the difficult ground! Once there, a Reloscope/ wedge prism sweep is done to determine which trees are ‘In’ and should be measured. Cruisers must “Play the Game” to ensure they have an average of at least 4 trees per plot. If they set the BAF too low they will get “nuked” and have to measure many more trees than they need to. Too high and they won’t get enough trees and will have go back and re-do the plots with a lower BAF. The last couple of plots can be very tense.

The dbh of trees is measured with a d-tape (no mean feat getting the tape around rough-barked trees more than a metre wide – learnt some neat tricks though!), and height with a Vertex. Timber quality is assessed and the trees graded according to a mind-bogglingly complex system. The main defects of trees here is frost crack and bracket fungi (referred to as “conks”).

A ’reference tree’ is selected, purple ribbon tied around it, and a ‘blaze’ created by slicing off the bark and outer sap-wood with an ax. On the blaze is written the plot ID, and the bearing and distance to find the plot centre. This is to give accountability so that auditors can at any time check the data collected.

timber cruising in vancouver

Liam (a fellow Brit!) standing at the plot centre, while Graham is about to take the dbh of a good-sized cedar.

Deflection Lines for Cable Logging

In areas of steep terrain and high value trees – which describes a large proportion of the landscape – blocks are harvested by cable logging. These cables run in straight lines perpendicular with the slope, and each end is attached to a spar. Given the distance they must travel and the sag of the loaded cable, it must be checked that the cable will not touch the ground. In order to avoid this major complication, the deflection lines of the proposed cables are checked. This involves scampering up and down steep slopes (rough average of 70%, but reaching over 100%) in pairs. The first person shoots off at an alarming speed, while the other waits. They have a string box recording the distance travelled, and they stop when they come to a change in slope. They focus a clinometer on the lower person (the undergrowth is so thick a torch is usually used to give them something to aim at). Slope and vertical distance are converted into horizontal distance (hd). Slope and hd are recorded in a note-book and also on ribbon tied at that point. From this data a profile of the hillside can be drawn. The cable is then projected onto this diagram and with some trepidation it is seen whether or not it will touch the ground.

Challenges and Canadian Solutions

  • The terrain. Especially in old-growth forest, the ground is like a half-finished game of pick-up sticks. Slippery logs are precariously balanced over one another, concealed by vegetation, and armed with sharp broken branches. Caulk boots, which have sharp spikes covering the soles, are mandatory and a life-saver. First aid kit, Emergency Response Plan, and Radios must be carried by all employees in the field. A map and compass are pretty essential as well when your fit and lithe companions disappear into the undergrowth ahead of you.

avoiding hazards in the forest

Snakes and ladders! Fallen logs make excellent highways or painful mistakes.

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Fairly typical terrain in old-growth forest. It is often so high and thick you have to use your arms to forge a away ahead, and it feels akin to swimming.

  • Equipment. The tasks often involve many different tools, and the truck will be a too-long slog away. Cruise vests allow you to pack everything you need in large, convenient pockets and carry it with relative ease for the entire day. They also help you develop strong shoulder muscles!
  • The weather. The zone name “Very Wet Hyper-Maritime” gives it away… A tough, bright-yellow, non-breathable, waterproof “banana suit” leaves one warm and dry (if slightly sweaty).

forestry kit

Getting kitted up. It is always a topic of tense debate whether or not to don the ‘banana suit’.

  • Wildlife. Most work is done in pairs, but when alone it is a good idea to have a ‘cougar knife’, and in some areas bear-spray as well. Cougars are very rare to see – your first warning is usually when one is already firmly attached to your back – but bears are common. Their poo is often found on the logging roads, and I saw my first while in the bush a couple of weeks ago. Mother and very adorable cub, who ambled off into the block we were heading for, forcing us to change plans.
  • Clouds of biting insects. Long sleeved shirts, liberally applied Deet, bug suits (in extreme areas), muffled curses, and the formidable grit of West coast foresters.

If you would like to know more about anything forestry related over here feel free to contact me, and I will do my best to investigate!

Connect with Ellinor Dobie via Twitter: @EllinorDobie

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