132 Depth of Sowing Grass and Clover Seeds. [MAY r 



DEPTH OF SOWING GRASS AND 

 CLOVER SEEDS. 



PAET II. 



R. D. Williams, B.Sc, 

 Plant Breeding Station, Aberystwyth 



White Clover. — In spite of the high percentage of surface 

 seedlings given by the surface sowings — 67 per cent, for the 

 pots and 75 per cent, for boxes — these sowings must be 

 regarded as failures on account of the stunted nature of many 

 of the seedlings. The best results were obtained when the seeds 

 were lightly covered. 



In the box experiment the best results were given by | in., 

 J in. and J in. depths; in the pot experiment J in., closely fol- 

 lowed by \ in. and f in. gave the greatest number of surface 

 seedlings. The f in. depth was only slightly inferior to the 

 shallower coverings, while the 1 in. depth in the pot experiment 

 gave about the same number as the shallower depths : but in the 

 box experiment which approximated more closely to field con- 

 ditions the number of seedlings that reached the surface from 

 1 in. dropped to 66 per cent, as compared with 92 per cent, 

 from § of an inch. When covered to depths of 2 and 3 in. 

 hardly any of the seedlings were able to break through to the 

 surface. 



Not only did the shallower depths (J in. to f in.) give higher 

 percentages of surface seedlings but the seedlings also reached 

 the surface sooner and more regularly; consequently the growth 

 was more even than at the J in. to 3 in. depths. When covered 

 to 2 or 3 in. depths the seedlings were very slender when they 

 reached the surface, and remained etiolated for quite a con- 

 siderable period. 



White clover seedlings closely resemble red clover seedlings 

 in form and general habit, but as the radicles are not so stout 

 and the tips not so blunt they are able to penetrate the sur- 

 face with greater ease than red clover seedlings. But as in 

 the case of surface sown red clover seeds, a considerable portion 

 of the radicle remains exposed on the surface even after the 

 seedlings have become fixed. 



When covered, white clover seedlings (with their smaller 

 cotyledon leaves) are able to force their way through fairly light 

 coverings with greater ease than the seedlings of red clover, thus 

 when sown at half an inch 95 per cent, of the white clover 



