Physical measurements

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Number of braids

Record the number of paths present and any braids (narrow worn desire lines, sometimes parallel to main path) that it will have to be managed. It is uncommon to manage more than one path if two paths arrive at the same destination point, although you may have situations where different users have specific requirements and more than one path is needed. For example, you may need to negotiate a slope that is too steep for people on wheels or horses, so a long shallow ramp is required, but decide that a set of steps is the only way to stop a short-cut developing.

Braid lines, on the other hand, occur close to the main line and usually develop as people try to find more comfortable lines. For example, the braids might have less rough surfaces, easier gradients or are drier under foot. Braids are path lines separated from the main path by a strip of vegetation or un-trampled ground; they are not simply the trampled path margins. Again, some judgement is required to record information which illustrates the nature of the path. Braids are often only 10 or 20 m long, and it is clearly impractical to have a section change every time a braid occurs or disappears. The record should however provide a flavour of the site – for example, if braiding occurs over a large proportion of the site and the section is likely to remain braided.

Path width

Both the bare (un-vegetated) width and the trampled width should be recorded. Look for the minimum and maximum widths along a section, as well as an estimate of the typical bare and trampled widths. For typical widths you do not need to take lots of measurements and find the mean, just recording an approximation is sufficient. In cases where ground vegetation has encroached onto a constructed surface you should record the original constructed width as the ‘typical’ and put a note about the encroachment in the comments.

If the path is braided the total amount of bare ground across the braided section should be given, so if the path comprises three lines each 1 m wide, then the bare width would be 3 m.

It is a little more difficult to measure trampled width accurately. The edges of the trampled path margins are not usually clearly defined, but damage to vegetation and changes in species composition are good indicators of trampling.

Eroded depth

The eroded depth is defined as the depth at which the path surface is below the surrounding ground levels. If the path surface is gullied, measure the maximum depth in the section.

Long gradient

Long gradient is measured along the path and is the gradient of the path expressed as a percentage. It is not necessarily the angle of the slope that the path is climbing or descending as the path may meander or zigzag up steep slopes in order to reduce the long gradient.

If long gradient is to trigger a change of path section it should be because it increases or decreases across a threshold that is significant in terms of erosion or path management processes.

Cross gradient or cross fall

Cross gradient or fall is defined as the steepest angle, in any direction, on the slope over which the path runs, i.e. the route and angle that a stone would naturally roll away or water runs.

Managing paths with low cross gradient can be quite problematic. If low cross fall is accompanied by low long gradient, it is difficult for water to run away from the path and drainage may be difficult.

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