Successful Farming p. 12-16 (1900)
William Rennie Sr.

SECTION III.
UNDERDRAINING.

The bacteria or germs can only act on dry warm soil. Therefore, in order to get the best results, it is necessary to underdrain wet lands, as these are usually too cold. It is not necessary to drain high dry land; deep subsoiling every three or four years on such land is found to give better results. Underdraining causes the surface water to percolate through the soil. At the same time sufficient moisture is retained to withstand a period of drought

For underdraining, there is nothing better than the ordinary round drain tile. Judgment must be used in the selection of the size of the tile to be used. It is necessary to have the tile sufficiently large, but not larger than is required, as the cost of underdraining is governed very much by the size of the tile used. For a main drain in ordinary cases, five or six inch tile may be used for the lower end, and four inch for the upper portion, and for the laterals (or branches) from two and a half to three inch. Drains should always be from two and a half to three and a half feet deep.

The distance apart or between the lateral drains is governed by the quantity of water to be carried off, and the quality of the subsoil through which the drains run. In a tenacious clay soil, thirty feet apart would be considered an average distance. In a free soil, the lateral drains may be sixty feet apart.

1. SUBSOIL PLOW.

In commencing to drain, open up with an ordinary plow, by passing three or four times in the same track. The subsoil can then be loosened with an ordinary subsoil plow. (See Ill. 1). The earth thus loosened to a depth of about two and a half feet can easily be thrown out with narrow shovels. The bottom of the drain should be dug with a narrow draining spade (see Ill. 2), made for the purpose, and the loose earth thrown out with a crummer. (See Ill. 3).

2. DRAINING SPADE.
3. CRUMMER.

To secure a proper grade for the bottom of a drain, use several cross‑heads made from strips of one inch boards, three or four inches wide. The length of standards varies according to the, depth of the drain. A cross‑piece, about two feet long, is nailed on the top of the standard. Place the cross‑heads so that the tops of the cross‑pieces are in line. The proper grade is ascertained by using an ordinary spirit level. When ready to lay the tile, set a standard or the handle of the crummer, at the bottom of the drain, and mark in line with the top of cross‑heads; this will, by testing every few feet, give a true grade for the tiles. (See Ill. 4).

4. DRAINING.

When laying the tile run them so that they join well and see that they are firmly laid. In making connection, make an opening in the main drain tile with a small mill pick, and fit the lateral tight. (See Ill. 5). In covering, put the black surface soil next to the tiles. The reason for this is, that the black surface soil is composed of vegetable matter and will prevent the subsoil from getting in at the joints. If the drains are properly laid, the least perceptible fall is sufficient to carry off the water without clogging.

5. DRAIN CONNECTION.

A correct diagram of all drains should be made and kept for future reference.

Ditching machines have not come into general use. Some years ago, the writer invented a ditching machine at great cost, which did good work, but it is not manufactured at the present time, as it was found to be too expensive (See Ill. 6).

6. DITCHING MACHINE.