THE FOREST NURSERY 291 



of the earlier germination, better hardening of the autumn 

 growth, larger proportion of root to shoot, and shorter, stockier 

 plants. Researches by Cieslar 1 show that coniferous seedlings 

 make their best growth in open seedbeds when the soil is pro- 

 tected by a mulch of moss or other litter which checks the loss 

 of moisture from the surface soil but permits the tops of the 

 young plants free exposure to the light. All species show an in- 

 crease in height growth with an increase in shade up to a given 

 degree, but it is more pronounced in intolerant than in tolerant 

 species. Although shade stimulates height growth, it depresses vol- 

 ume growth of both root and shoot and tends to produce less acceptable 

 stock for the general purposes of planting. Shaded stock does not 

 ripen its wood so well in the autumn and, as a consequence, is 

 more subject to frost damage. 



Although better stock can often be grown in open seedbeds, 

 particularly when a mulch is worked in about the plants as soon 

 as they are up, the danger from the drying out of the young plants 

 in open beds is usually so great that shading must be resorted to in 

 order to overcome the hazard of excessive loss. Overshading is de- 

 cidedly harmful. Only sufficient shade should be given to prevent 

 injury. 2 



The economic necessity for shading the seedlings must be deter- 

 mined for each locality through experience. Western yellow pine, 

 Scotch pine, and Austrian pine are successfully grown without shade 

 at the Wasatch nursery and some other western nurseries at high 

 elevations. Larch, spruce, and fir are grown under shade the first 

 year. Autumn-sown seedbeds of all conifers are unshaded at the 

 Wind River nursery, while it has been found economically advan- 

 tageous to shade spring-sown beds during the first season. At the 

 Halsey and Fort Bayard nurseries and at other western nurseries 

 located at low elevations where the air is warm and dry during 

 the growing season, all coniferous seedbeds are shaded. Although 

 western yellow pine can usually be grown without shade after the 

 seedlings are a month old, spruce and fir should often be shaded even 

 during the second and third years in order to attain the best 

 economic results. In New England and elsewhere east of the 



1 Cieslar, A.: Licht- und Schattholzarten : Lichtgenuss und Bodenfeuch- 

 tigkeit. (Centralblatt f. d. gesamte Forstwesen, S. 4-22. 1909.) 



2 Pearson, G. A.: Forest planting in Arizona and New Mexico. (Proc. 

 Soc. Am. For., vol. IX, p. 463. 1914.) 



