HOW TO TEST A FIELD. 19 



HOW TO TEST A FIEL,I>. 



In some European countries where horticulture 

 and agriculture are more advanced than they are 

 are in this country, the tillers of the soil have certain 

 test plants ; that is, certain quick growing plants, as 

 oats, are planted and their color and growth watched, 

 and from these the conditions of the soil interpreted. 

 In this way the soil is tested and it is learned just 

 what elements are wanting to make the crop remu- 

 nerative. In this country the tests have not been 

 thorough enough nor continued long enough to make 

 them of value. However, certain good horticulturists 

 can tell to some extent by the condition of the foliage 

 what is wanted by certain plants. To obtain infor- 

 mation of this kind, it requires careful attention to 

 various crops grown on different grades of land whose 

 composition is known and to keep careful notes on 

 these for a long series of years. Unfortunately, there 

 are so many other conditions that come in to vary the 

 test that most people become impatient before any 

 definite conclusion could be reached. 



Our sandy soil is unusually well adapted to work of 

 this kind, as so much of it is deficient in all the essen- 

 tial fertilizing elements. Any one raising vegetables 

 could withhold one of the three necessary fertilizers 

 for a series of years on as many different plots as there 

 are elements and thereby learn the effect of such treat- 

 ment, and then by noting the color of the foliage, form 

 of growth and other characters, learn to interpret 

 these when observed in other fields. 



To test a field to learn whether it really needs all 

 the elements of a complete fertilizer, we may proceed 

 as follows : Choose four rows of, say, tomatoes that 

 run across a typical portion of the field and withhold 

 from these one of the fertilizer elements, we will say 

 nitrogen ; then treat four rows the same as the rest of 



