THE FOREST NURSERY 



279 



operation easier and eliminates the danger of deep covering. Even 

 with the greatest care the even distribution of the seed is disturbed 

 and the resulting stand is likely to be irregular when the seed is 

 covered by raking. The covering soil should be sifted over the seed- 

 beds. A strong, circular sieve 

 with ^-inch mesh, such as is com- 

 monly used by gardeners (Fig. 

 63) or a rectangular sieve of the 

 same length as the width of the 

 bed may be used (Fig. 64). The 

 former is handled by 1 man 

 while another shovels in the soil. 

 The latter is handled by 2 men, 

 one on each side of the bed 

 while a third keeps it filled 

 with soil. The larger sieve per- 

 mits of more rapid work and 

 is recommended when a large 

 area of seedbeds is sown. The covering soil should be but 

 slightly moist. If overwet, it sticks to the sieve and cannot be 

 rapidly and evenly applied. Although experience at the New York 

 State nurseries and at the Yale School of Forestry indicates 



FIG. 63. Circular sieve. 



FIG. 64. Rectangular sieve. 



that a covering of fine loam induces better germination than 

 sand, the latter is preferable because of its freedom from crusting 

 when wet. It is very important that the covering soil be free from 

 weed seed and the spores or mycelia of damping-off fungi. 

 Surface soil should not be used. Excavations should be made 

 and the covering soil taken from a foot or more below the surface. 

 Watch should be kept over the beds during the operation of covering 

 and only sufficient soil applied to cover the seed. For most coniferous 

 species \ inch is ample when the beds are protected by mulching 



