20 BULLETIN 479, U. S. DEPARTMENT OF AGRICULTURE. 



METHODS Ol NOW1NC1. 



Whether sowing shall be broadcast, in drills, or in Hats will be 

 governed largely by local conditions. Each method has advantages 

 under certain conditions. 



In drill-sown beds cultivation and weeding between the rows by 

 means of small hand tools is possible, and root pruning can be prac- 

 ticed. Where cultivation is practiced there is less need of watering, 

 and the soil is better aerated and is kept warmer and in better tilth. 

 Even stands are more easily secured by an inexperienced man in 

 drill sown than in broadcasted beds; seedlings can be more easily 

 dug and with less damage to the roots, particularly in heavy soils, 

 and in some cases winter damage from snow (as with Douglas fir at 

 the Cottonwood Nursery) and heaving are less serious. Damping- 

 off can be more readily controlled by cultivation when the beds 

 are drill sown than when they are broadcasted, provided the con- 

 ditions are such that cultivation is effective against the disease. 

 Such cultivation, however, is seldom effective. On the other hand, 

 the drill-sown seed in germinating may break the soil and leave 

 an open ditch in line with the drills, thus exposing the seed which 

 have not yet germinated. WTiere damping-off is prevalent this 

 partly open ditch forms an ideal moist chamber for the development 

 and spread of the fungus along the whole row. At the Priest River 

 Experiment Station damping-off has been more serious in drill-sown 

 western yellow-pine beds than in broadcasted. Drill sowing is not 

 well adapted to the sowing of seed with a low germination per cent, 

 because the drills must be made deep and the seed sown very thick 

 in the row, with the result that a portion of them do not come in con- 

 tact with the soil, and the bottom seed are covered so deeply that 

 upon sprouting they are unable to push their way through the cover- 

 ing above them. 



In broadcasted beds cultivation is not possible and weeding must be 

 done by hand, but if the beds are fully stocked the plants will shade 

 the ground completely, decreasing evaporation and killing out the 

 weeds, so that there is less need of these operations. A greater num- 

 ber of good seedlings can be grown per square foot in broadcasted 

 beds; if necessary an area can be resown without disturbing the 

 original stand ; and the plants are less crowded and in general reach 

 better development than in drill-sown beds. Broadcasting permits 

 the necessary heavy sowing and uniform covering of seed having a 

 low germination per cent. 



In general it seems that in heavy soils or at nurseries where the 

 water supply is deficient, either of which makes cultivation desirable, 

 or where root pruning is to be practiced drill sowing is preferable. 

 Where cultivation appears unnecessary and the water supply is suffi- 



