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  IT has been previously stated that Keyline cultivation parallels from the Keyline up the slope of the land and from the Keyline down the slope of the land. However, there are very many properties that do not contain Keylines or a single Keyline, and so a means of the simple application of Keyline cultivation on such lands needs a Guideline on which to work.

  These areas or farms are treated in the same way as are all areas below the Keyline. Cultivate the land parallel to the highest suitable Guideline, always working parallel down the slope of the land.

  The line that forms the overall or planning guide on these properties is called a General Guideline, and, as with the Keylines, may be either a selected true contour line or a line with a very gentle slope. The slope would be for the purpose of a water race connected to a water storage.

  The special or significant feature of all land lying below the Keylines is that the valley slopes are generally flatter and wider than the adjacent ridge slopes that form the valleys. This was fully explained in Chapter 2. The aim of Keyline cultivation is the equalising of the moisture between the wettest and the driest parts, that is between the valley and the adjacent ridges. To do this most effectively a Guideline is located in the highest position, where it can serve as a guide for Keyline cultivation.

  If the slope is long, another Guideline at a lower level is located. It lies at a convenient distance below to serve as a boundary to the upper area. This is a Lower Guideline and it is usually a true contour line. It is marked by any suitable means, preferably one that permanently locates it.

  The control and development of these areas is approached first from a consideration of water which flows down to the valleys from the higher country outside. The entry of this run-off water is usually at the lowest point along the highest boundary fence. This may also locate the Guidepoint from which a level or sloping line in both directions suitably forms the General Guideline.

  If a large area of land lies above the selected General Guideline it will be necessary to locate an upper Guideline to control the Keyline improvement of the higher area. If so, the upper Guideline is located and marked as high in the area above the General Guideline as possible. Care should be taken to see that it is of sufficient length to serve its purpose.

  Outside run-off water may now be a problem. Perhaps the main factor in determining the General Guideline will be the position of a suitable conservation dam site for the storage of this extremely valuable water. This site is looked for in the highest third of the area, and when located the General Guideline becomes a suitable water race to the dam site.

  All the details of farm planning above the Keyline also apply above the General Guideline of the land below the Keyline.

  The main grazing or large cultivation area is below the General Guideline. A Lower Guideline located at a suitable distance below forms the top boundary of another group of smaller paddocks. If their vertical distance below the conserved water is sufficient, gravity spray irrigation is always planned. Five per cent. of a grazing property that is suitably planned and supplied with water for gravity spray irrigation may add fifty per cent. or much more to the capital value of the whole property.

  In the development of timbered areas of this type of country, clearing is done to leave suitable timber strips along the General Guideline and all Guidelines.

  The formula mentioned in Chapter 8, which relates the vertical distance apart of these tree strips to the general height of the trees, is again the planning guide.

  Map 6 illustrates in simple form a valley area below the Keyline and the location of the Guidepoint and General Guideline. The parallel lines on the map which start from the General Guideline and parallel it downward illustrate the drift of water out of the valley. This compensates the natural water concentration in the valley. Keyline cultivation is again completely effective.

  In selecting the Guidepoint--in place of the Keypoint of properties containing their own Keyline--it may be advisable to locate it just away from the fence at the lowest point along the highest boundary. A distance of 20 feet from the fence would allow a farm road to cross the paddock above the General Guideline.

  Soil erosion by water is simply and profitably cured on flatter lands by the methods of this book.

  There is, however, a type of erosion that appears to defy man's efforts to cure it when these efforts are confined to "maximum soil improvement". This is the serious periodic erosion by wind, which occurs alike on poor soils and fertile soils of our marginal lands.

  Following a period of three or four years of much drier than usual conditions on this country when it has a normally sparse rainfall, this serious wind erosion manifests itself. If the latter end of a dry period coincides with that of a severe drought, followed by high wind, these soils will move in vast quantities.

  The dry period or the severe drought cannot be controlled and the only possible solution to this problem lies in measures designed to retard the ground velocity of the winds. A rough cloddy surface will reduce a 60 m.p.h. wind to a velocity that will not raise any appreciable dust from this soil, but at the end of such a period of weather conditions as described the surface condition alone will not have sufficient effect.

  The growing of sufficient tree strips is the only possible means of reducing the high velocity of these winds to such an extent that the soil will not blow. The problem is one of great magnitude and the solution in the planting of trees must be of like proportions.

  Indigenous trees can be induced to grow by leaving protected strips of land in the right pattern. This is the lowest cost means of growing the tree strips on a large scale. If the country is treeless, then tree species will have to be introduced which will not only grow well in this country but survive the period of very dry conditions.

  Nothing can be done during the time of the actual blows that will give results commensurate with the money expended. The planning of the work can be satisfactorily done at this time so that when better rainfall conditions follow the drought the land will be in a position to make quick rejuvenation. Four years later this land could be safe from wind, erosion.