520 L. ZUFA 



The rooting in coarse sand was significantly better than the 

 rooting in clay loam or in a mixture of coarse sand and humus (Table 7) 



Table 7. Rooting of P. strobus cuttings obtained from ortets 

 5 years old and planted in 3 media: May collection 



Media No. rooted % rooted 



Clay 5 6.0 



Sand 53 63.1 



Sand and humus 5 6.0 



X 2 = 86.84*** a d.f. = 2 



*** Significant at the .1% level 



The within population variation was significant in four cases but 

 was not significant in two cases (Table 8)'. 



Table 8. Variation of percentage rooting within ortets: May 

 collection 



No. of 

 Ortet Age in cuttings Ortet No. and % rooted 

 population years per ortet 1 2 3 4 5 d.f. x 2 



42.8 



7.7 11.5 15.4 15.4 3.8 4 9.40 j 



i 



P. strobus 



5 



26 



P. strobus 



10 



26 



P. griffithii 







x strobus 



2 



6 



16.7 33.3 0.0 50.0 -- 3 55. 5* 1 



P. griffithii 



x strobus 5 26 38.5 84.6 -- -- -- 1 17.26' 



P. griffithii 



x strobus 5 26 0.0 0.0 -- 1 0.0 



P. griffithii 



x strobus 15 26 7.7 15.4 15.4 11.5 0.0 4 6.59 



* Significant at the 5% level; ** Significant at the 1% level 



The difference in rooting between the two P. griffithii x strobus 

 populations of the same age was significant (Table 9) . Likewise, P. 

 griffithii x strobus rooted significantly better than P. strobus 

 (Table 10). 



