EXPERIMENT WITH A PLANT 157 



peas have been grown. When the last bundle has 

 been taken in, it is my practice to dig and well manure 

 the ground as soon as possible, and to plant it at 

 once with vetches, to be dug in, in January, as 

 a green manure. For sowing the vetch, the ground 

 is left fairly rough, and shallow drills, one foot 

 apart, are drawn across it ; the seed is sown 

 broadcast, and the ground is then nicely raked 

 over with a fine rake. If the weather has been 

 favourable it should be possible to finish the har- 

 vesting and get the vetches planted by the end of 

 August ; and, of course, the earlier they can be 

 got in the better, for the more growth will they have 

 made when the time comes to dig them in. Besides 

 acting as a valuable green manure, the vetches serve 

 other useful ends. To a certain extent they keep 

 weeds down by smothering them; and, by keeping 

 the frost out of the ground they render it possible 

 to begin tilling the ground at an earlier date in the 

 year. In January of this year, 1911, a frost, which 

 had left a piece of ground, adjoining the patch 

 in which the vetches were, so hard that it was 

 impossible to work it with a spade or a fork, had not 

 touched the ground in which the vetches grew. This 

 was perfectly soft and open, and the vetches were 

 dug in with the greatest ease. 



My practice is not to use this patch again for 

 peas before two years have elapsed. 



The reader who wishes to repeat Mendel's obser- 

 vations will require to know the names of those 

 varieties which bear the various characters dealt 



