picture of a logging road Because access is vital to a well-managed woodland, we’ve borrowed from our favourite resource again to help you think about planning your road network.

A road network system serves many transportation purposes including the extraction of timber, access for silviculture treatments, fire control and recreation. In developing a road network, your objective is to provide for these uses with the minimum disturbance to the land base and your pocketbook.

To do so, you’ll need to consider a number of different forms of access to your property:

  • general access via main roads and trails
  • new logging roads for the removal of timber:
    • during planned harvests
    • to take advantage of fleeting niche market opportunities
    • to salvage timber killed by blow down or insect attack
  • branch roads for spacing, thinning, and pruning
  • protection roads to water sources

The building standard will vary with each type of access, depending on the type of vehicle and volume of traffic it will carry, as well as the season of use. Good planning, engineering and construction are key to keeping costs acceptable.

Your road needs depend on:

  • your management 
objectives
  • the
 location and
 characteristics of your
 timber
  • terrain 
conditions (such as 
rock, swamp, slope)
  • the silvicultural 
system and logging 
methods you plan to use

Part of your initial considerations should include the assessment of existing access roads and trails. One of the benefits of working in second growth stands is the presence of old roadbeds, railway grades and skid trails from when the stand was first managed.

In these areas only minor road upgrading, such as widening or spur road development may be required to complete an access network, and you can often acquire enough knowledge to do it yourself. A quick walk or drive around the existing road network with an experienced logging truck driver can be very educational.

Where major road location and construction are required to develop a woodland area, an experienced contractor or consultant should be called in to ensure the most efficient and safe road system is developed.

How Do I Plan a Road Network?

Your first task in planning your road network will be to sketch out main routes that provide the best coverage of your woodland and access to particular sites of importance. The purpose of this initial plan is to locate the road network to cover the whole area, while minimizing the total length of road required.

Begin the process of road location at the drawing board, with aerial photos and a good contour map of the area. Pencil out possible road routes based on the following considerations:

  1. Follow contour lines where possible. Try to minimize grades where practicable.
  2. Avoid depressions which may catch and hold water.
  3. Steer clear of trouble spots such as swamps, rock outcrops, etc.
  4. Minimize the number of stream crossings.
  5. Keep a distance from stream and leave a ‘green belt’ of undisturbed soil and vegetation between roads and waterways to filter runoff and minimize erosion.
  6. Identify potential sites for landings (flat areas for loading logs onto trucks), wide spots and turnarounds, such as saddles, benches or ridges.
  7. Make use of old road grades or common road systems wherever possible.
  8. Road curves should be located on minimum grades. Try to avoid sharp curves, but if unavoidable, provide extra road width in these curves.
  9. Avoid unstable soil conditions that could create erosion problems and deposit sediment in fish bearing streams.
  10. Watch for potential sources of gravel or fractured rock to be used for road balasting and culvert beds. Rock cuts can also provide material for armouring culverts, dispersing runoff and preventing erosion.
  11. Note requirements for culverts and bridges.

Ideally, the road system should be planned for long- term use and to be suitable to access stands that are currently immature but will be harvestable at some point in the future.

Depending on the terrain and control points (e.g. stream crossings, rock bluffs) main access roads should have a spacing of 300–400 m and 100–200 m distance to the woodland boundary. Additional, short spur roads or forwarding trails will help to further access pockets and bands of harvestable timber.

For ground-based harvesting systems, the access roads should be located at the lower end of the slope. For cable-based harvesting systems, it is best to have the road located at the slope ‘break’ at the top of the slope. However, if necessary, uphill yarding on moderate slopes is possible with some ground-based harvesting systems (i.e. hoe chucking, track skidders) and cable systems can usually cope with down hill situations.

Your roads, once built, aren’t moved easily, so be sure to discuss your plans with an experienced road builder and logging contractor before proceeding.

As always, thanks to A Non-forester’s Guide to Small-scale forestry in British Columbia for the information excerpted above. Please stay tuned for more on road planning and construction in our next Standing Tending 101 post.

In the mean time, you can access the complete resource online here.