Vetcli as Subsoilers. 83 



in disintegrating the apparently impenetrable pan.* 

 Altogether, we estimated that the roots had gone down 

 about 30 inches. The burnet and kidney vetch roots 

 had gone down about 20 inches, and the lucerne from 

 8 to 10 inches. It was interesting to observe how the 

 clover plants had turned into plants more or less robust 

 and large, in accordance as their roots were supplied 

 with a larger or smaller quantity of those nodules which, 

 in the opinions of the best authorities, have been now 

 proved to supply the plants with nitrogen derived from 

 atmospheric sources. Altogether, we came to the con- 

 clusion that the roots of these plants are capable of 

 doing all the work of a subsoiler in breaking up the 

 pan, which is often the most formidable obstacle to be 

 contended with in the cultivation of all our old arable 

 soils. I increased the chicory in the case of this field 

 by one-third, as I wished deeply to pipe, and so aerate 

 the soil, and bring up the manurial matters which must 

 have filtered downwai'ds in past years. Arthur Young, 

 I may observe, objects to chicory for hay on the ground 

 that it is difficult to dry, and no doubt there is some- 

 thing in this objection ; but I have found two advantages 

 from its use — one is that, as a certain proportion of it 

 always throws up long strong stems pretty early, these 

 support the whole crop, and so greatly increases it, and 

 favours the grasses generally ; the other is, that the 

 stems of the chicory aerate the cocks of hay, and cause 

 it to dry much more quickly. Hay with chicory in it 

 should be used within a year, as, if kept longer, it 

 creates much dust in the hay. I usually sow 2 lb. of 

 chicory, and think this is, as a rule, a sufficient quantity, 

 but that in dry lands 3 lb., and perhaps even 4 lb., may 

 be used with advantage.! 



* This pan was composed of very small particles of soil washed 

 down from the soil above. This pan evidently was not formed solely 

 from ploughs and horses, but owed much of its hardness and compact- 

 ness to the smallness of the washed down particles, which may be so 

 small at to arrest capillary attraction. 



+ I have since overcome the objections to chicory as regards the 

 hay crop by grazing the land late in the spring. ( Vide Bank field 

 experiment, Appendix III. ) 



