HORTICULTURAL RESEARCH 291 



to growers, as it is a costly operation, especially in stiff soils 

 where it may be expected to do most good. The trenching 

 usually adopted (bastard trenching) consists in digging and 

 moving the first and second depths or spits of soil and breaking 

 up but not removing the third spit ; the second and first spits are 

 then put back into their original position. Ploughing with a sub- 

 soil plough is sometimes substituted for trenching. In vegetable 

 growing, trenching is generally understood to mean more than 

 this, a liberal supply of dung or refuse being buried in the 

 trench drawn out in the course of the digging ; this materially 

 alters the character of the soil. Trenching in its strict sense 

 has alone been investigated. The investigation embraced five 

 instances in different soils, fruit-trees being planted in the 

 trenched and untrenched ground and their behaviour examined. 

 At the same time the alteration effected in the soil by the 

 trenching was investigated by Dr. E. J. Russell, who determined 

 the water and nitrogen present in the various cases. The 

 results have not been quite completed yet but they are suffi- 

 ciently advanced to show that trenching has very little effect, 

 when measured either by the behaviour of the trees or by the 

 alteration in the soil. In many cases the effect has been ml 

 and whether it be appreciable or not seems to depend chiefly 

 on the character of the seasons following the trenching. In 

 any case, the beneficial effect is much too slight to compensate 

 the planter for the cost of the operation. 



