Trenching

From Gardening Wiki

Methods of Trenching

There are two methods of trenching known to gardeners namely, double trenching, which means the disturbance of the soil to the depth of either two or three " spits " or spades, one below the other ; and bastard trenching, in which the position of the two spits of soil is not reversed, the lower spit being merely broken up and the top spit turned over on itself. Let me explain the two processes in a little more detail :

Double Trenching

First of all mark out the piece of ground to be trenched in convenient sized portions, either in squares or oblongs. At the extreme end of one of the sections dig out a hole to the desired depth say three feet at least and wheel the soil thus removed to the other extreme end of the section.

Here it should be allowed to remain until the whole piece of ground has been operated upon, for it will be required to fill up the final hole or trench. If the soil is good throughout there need be no hesitation in turning the next subsection completely over, beginning at the top, and throwing the soil into the bottom of the first trench or hole, bringing the lower layer to the top, so that what was formerly three feet below now becomes the surface soil. So the process of trenching goes on until the last subsection to be operated upon is reached, and if the work has been carried out systematically it will be found that the soil removed from the first hole made will be just sufficient to fill the final trench after it has been excavated to the proper depth.

BASTARD TRENCHING

Bastard Trenching is practised when the subsoil is of such inferior quality that it would be to court disaster to bring it immediately to the surface. In this case it is necessary to leave the lower spit of soil in its original position, and merely to break it up thoroughly before returning the top spit to its original position. In bastard trenching it is usual to work to a depth of two feet or two " spits."

The necessity is to take out a trench to a depth of two feet, and wheel it back, as in the case of double trenching, to the other extremity of the section of ground to be operated upon. The next subsection should now be tackled, and in this case only the top spit should be removed. This also must be taken back to the extreme end of the section, and placed beside the original heap. At this stage the situation is that we have one hole two feet deep and another hole, immediately next to it, only a foot in depth.

The next operation consists in moving the soil at the bottom of Hole 2 into the bottom of Hole 1, meantime thoroughly breaking it up if it be hard, and at the same time incorporating with it a forkful or two of well-decayed farmyard or stable manure. The top spit of the third subsection is now dug out, and becomes the surface soil of Subsection 1, and these operations are repeated until the whole piece of ground has been trenched.