DRAINAGE 147 



$40 per acre or upwards. There are practical cases, how- 

 ever, where tile drains pay on cheap lands, as where one 

 line of tile will carry off the water from a large area. 

 The judgment of an expert is often worth securing to 

 determine whether the probable profits will be sufficient 

 to warrant the expense of a drain, as well as to plan the 

 proposed drain. 



How to determine where drainage is needed. The 

 farmer who sees his lands from season to season can 

 determine the injury to crops, or the difficulty of raising 

 desired crops on any wet areas. The purchaser who 

 would estimate the need and the probable cost of drain- 

 age on lands which he desires to purchase, must depend 

 largely upon inspection and upon the credited state- 

 ments of those who have observed the land for a series 

 of years. If there is water on the surface, if wild plants 

 which grow only upon wet soils are found, or if there is 

 other evidence that the soil is not suitable for those 

 crops which thrive best on arable land, the need of drain- 

 ing is easily seen. In some instances useful facts can be 

 learned by making holes here or there with a spade or a 

 pesthole auger, and observing, from time to time, the 

 height of the ground water in these little wells. By 

 studying the soil throughout successive seasons, im- 

 portant facts may be learned. Where the land is in cul- 

 tivated crops, or even in tame grasses, the effect of the 

 water in doubtful areas may easily be studied as affecting 

 the health and yield of the crops. Most domesticated 

 plants growing in soil containing more water than they 

 need become yellow, do not grow luxuriantly and yield 

 but little, and sometimes are killed. 



The area of the watershed which discharges its water 

 over any given area must be carefully determined and 

 taken into consideration in determining whether the land 

 needs draining, so as better to estimate the amount and 

 influence of the flood water. Sometimes a simple 



