136 



DIRECT SEEDING OF TREES 



W. E. MCQUILKIN 



Growing tree seedlings in a nursery 

 and transplanting them later to the 

 field is the standard artificial means 

 for establishing forest plantations. On 

 good sites and poor, in wet years and 

 dry, the use of nursery stock, properly 

 grown and properly planted, has 

 proved more likely to succeed than any 

 other artificial method. 



Direct seeding, which means sowing 

 seeds in the field where the trees are 

 to grow, thus bypassing the nursery 

 and transplanting operations, under 

 some conditions may be a simpler, 

 faster, and less expensive reforestation 

 method. Because of certain inherent 

 drawbacks, however, direct seeding is 

 not regarded as a method to replace 

 planting on a wide scale, but rather 

 as a useful adjunct to it by which, in 

 selected situations, reforestation can be 

 speeded up and costs reduced. 



By conservative estimates, we now 

 have in this country at least 30 million 

 acres of land in need of artificial re- 

 stocking. Obviously, any procedure 

 that will facilitate getting this land 

 back into forest production should be 

 fully utilized. 



ADVANTAGES AND DISADVANTAGES 

 will first be considered. With proper 

 procedures on selected sites, direct 

 seeding may be done successfully at 

 lower cost than for planting nursery 

 stock. Furthermore, since direct seed- 

 ing is not dependent upon maintenance 

 of a nursery and the starting of stock 

 1 to 4 years in advance, it permits a 

 degree of flexibility in reforestation 

 programs according to availability of 

 labor, allotments of funds, and the 

 press of other jobs that is impossible 

 with planting. If curtailment is neces- 

 sary, seeds can be held over a year or 

 so more easily than growing nursery 

 stock ; with expansion, seed usually can 

 be procured upon shorter notice and 

 with less advance planning. Also, seed- 



ing can be done over a considerably 

 longer season. 



Growth direct from seed in the field 

 permits normal development of root 

 systems. Transplanting at best entails 

 mutilation of roots and a set-back in 

 growth. Although most species seem to 

 suffer no lasting damage when prop- 

 erly handled, many cases of poor 

 growth and disease in forest planta- 

 tions are believed to be caused by mal- 

 formed root systems that result from 

 improper or careless planting. Some 

 strongly taprooted species seem by 

 nature poorly adapted to withstand 

 transplanting they typically suffer 

 high mortality, and many of the sur- 

 vivors fail to regain the vigor of nat- 

 ural, undisturbed trees. With direct 

 seeding, all depressive after-effects of 

 transplanting are avoided. 



On very stony areas, direct seeding 

 is especially advantageous. Successful 

 planting at reasonable cost on such 

 sites may be almost impossible because 

 of difficulty in digging holes to required 

 depth and in finding enough rock-free 

 soil to make a proper refill around the 

 roots. Trees starting from seed in such 

 ground are able to extend their roots 

 around and between the stones, and 

 may make excellent growth. 



Opposed to these advantages is one 

 major disadvantage that relegates di- 

 rect seeding to a secondary place; 

 namely, that with a few possible ex- 

 ceptions (such as on extremely stony 

 ground) direct seeding almost always 

 entails greater risks of failure than 

 planting nursery stock. 



Greater risks are inherent in the 

 method. Because of greater palatabil- 

 ity to wildlife, greater susceptibility to 

 certain types of insect injury and dis- 

 eases, smaller size, undeveloped root 

 systems, and generally greater fragility, 

 seeds and newly germinated seedlings 

 in the field almost unavoidably are 

 more vulnerable to injury and death 



