APPENDIX A. 



555 



If there is hardpan or heavy clay present, an unbroken lump of it 

 should be sent, for much depends on its character. 



Seventh. When in the case of cultivated lands, it is desired to 

 ascertain the cause of differences in the behavior or success of a crop 

 on different portions of the same field or soil area, do not send only 

 the soil which bears unsatisfactory growth, but also the one bearing 

 normal, good growth, for comparison. In all such cases, try to ascertain 

 by your own observations whether or not the fault is simply in the sub- 

 soil or substrata ; in which case a sample of surface soil sent for exam- 

 ination would be of little use. In such examinations the soil probe will 

 be of great service, and save much digging or boring. 



Eighth. Specimens of alkali or salty soils should preferably be taken 

 towards the end of the dry season, when the surface layers will contain 

 the largest amount of salts. A special sample of the first six inches 

 should in that case be taken separately by means of a post-hole auger, 

 and then, in a different spot close by, a hole four feet deep should be 

 bored, and the earth from the entire four-foot column intimately mixed 

 before the usual quart sample is taken. Samples of the plants growing 

 on the land should in all cases be included in the package, as they in- 

 dicate very closely the agricultural character of the land. 



All samples taken while the land is wet should be air-dried before 

 sending; in the case of alkali soils this is absolutely essential. 



Ninth. All peculiarities of the soil and subsoil, their behavior under 

 tillage and cultivation in various crops, in wet and dry seasons, their 

 location, position, " lay," every circumstance, in fact, that can throw 

 any light on their agricultural qualities or peculiarities, should be care- 

 fully noted, and the notes sent by mail. Without such notes, specimens 

 cannot ordinarily be considered as justifying the amount of labor involved 

 in their examination. Any fault found with the behavior of the land 

 in cultivation or crop-bearing should be specially mentioned and de- 

 scribed. The conditions governing crop-production are so complex 

 that even with the fullest information and the most careful work, cases 

 are found in which as yet the best experts will be at fault. 



