110 MISC. PUBLICATION 4 3 4, U. S. DEPARTMENT OF AGRICULTURE 





The best conifer planting stock usually has ratios of 1:1 up to 3:1. 

 Stock with higher values than 3:1 does not usually survive so well 

 in the field, although this figure will vary somewhat by species and 

 depends on the total weight and caliper of the plant. Poorer survival 

 in stock with a high top-root ratio is partially attributed to the rela- 

 tively large transpiration area in proportion to the absorbing area of 



2.50 



2.00 



COFFEETREE 













COTTONWOOD'"^ 











/ CHINESE ELK 



~~S 





/ 





s' /GREEN ASH 







^-.HONEYLOCUST 



1 



2.50 



1.00 



DESERTWILLOW — . 



^-HACKBERRY 

 SOAPBERRY 



2/16 4/16 6/16 8/16 10/16 2/16 4/l6 6/16 8/16 10/16 



CALIPER OF STEM (inches) 



IS.FSW.O -1940 



Figure 40. — Stem-root ratio of various caliper classes of l-year-old nursery and 

 wilding stock; the cottonwood and tamarix were wilding stock, and other 

 species were nursery grown. 



the roots and the consequent difficulty in supplying adequate moisture 

 for the plant under stress. 



Deciduous nursery seedlings usually have lower values than conifer 

 stock. In figure 40, giving measurements of 14 species of deciduous 

 trees, and 2 shrubs, it will be noted that almost all of the stock had a 

 ratio of less than 1:1. The smallest with the best stem-root ratio had 

 the poorest survival, while the largest trees with a ratio slightly poorer 

 than average had the best survival. From this evidence, it was 

 concluded that stem-root ratio was of little use in gaging the quality 



