20 



BULLETIN 1105, U. S. DEPARTMENT OF AGRICULTURE. 



Table 8. — Distribution of first-yea?" seedlings icith reference to seed tree». 



A.— INDIVIDUAL PLOTS ON AREA 3A, AUGUST, 1919. 

 Group l. 



Natural 

 plots 



5bvl0 

 leet. 



Distance i and direction of 

 nearest seed trees. 2 



Number 

 of seed- 

 lings per 

 square 

 foot. 



Culti- 

 vated 

 plots 

 5 by 10 

 feet. 



Distance 1 and direction of 

 nearest seed trees. 2 



Number 

 of seed- 

 lings per 

 square 

 foot. 



E-l.... 



E-2.... 

 E-3.... 

 E-i.... 



40 feet W., 50 feet E . ; sun 



foot E., 35 feet NW,; sun 



25 feet N., E., W.; group; sun. . 

 35 feet N. and E.; sun 



1.22 

 3.70 

 2.04 

 1.60 

 .42 

 1.34 

 3.84 



5.20 

 1.44 



4.70 



F-l.... 

 F-2.... 

 F-3.... 

 F-4.... 

 E-5. . . . 

 F-6. . . . 

 F-7. . . . 

 F-8.... 



F-9. . . . 

 F-10... 



40 feet W., 50 feet E.; sun 



foot E., 35 feet NW.; sun 



30 feet N., E., W.; group; sun. . 



0.46 



2.76 



1.32 



.28 



E-5.... 



60 feet N. and E.; sun 





.62 



E-6.... 



E-7.... 

 E-8.... 



40 f eetN . , 65 feet W. ; group ; sun 



5 feet W. ; group; shade 



10 feet S., E., and W.; group; 



45 feet N., 65 feetW.; group; sun 



5 feet W. ; group; shade 



10 feet S., E., and W.; group; 



.88 

 8.44 



8.68 



E-9.... 

 E-10. . . 



40 to 60 feet, all around; sun. . . 

 5 feet W.; group; part shade... 



40 to 60 feet, all around; sun. . . 

 5 feet W;. group; part shade... 



1.12 

 3.00 



Group 2. 



Group 3. 



Natural 

 plots 



5 by 20 

 feet. 



Distance 1 and direction of 

 nearest seed trees. 2 



Number 

 of seed- 

 lings per 

 square 

 foot. 



Natural 

 plots 



5 by 20 

 feet. 



Distance ' and direction of 

 nearest seed trees. 2 



Number 

 of seed- 

 lings per 

 square 

 foot. 



F-4.. 



100 to 12.5 feet, all around; sun.. 



50 feet W.; 80 feet E.; sun 



50 feet E., 70 feet S.; sun 



10 feet S. ; group; shade 



100 to 125 feet, all around; sun.. 

 30 feet N. ana NE.; group; sun. 

 75 to 100 feet, all around; sun. . 

 40 feet S. ; group; sun 



0.51 

 .99 

 .73 



4.62 

 .44 



1.22 

 .45 



1.04 



22 

 23 

 24 



20 feet N. ; group; sun 



1.85 



H-4.... 



1-4 



J-4-5. . . 

 L-l . . . . 

 H-7.... 



1-7 



1-8 



100 feet SW., 120 feet SE.; sun. 

 120 feet W. and S.; sun 



.60 

 .37 









i Distances measured to edge of crown. 2 Location of plots and trees shown in figure 1. 



B.— SUMMARY BY AREAS. 



Designation of area. 



Basis 

 number 

 of plots. 



Number of first-year seedlings per square 

 foot at various distances from seed 

 trees. 



Character of 



0to25 

 feet. 



25 to 50 

 feet. 



50 to 100 

 feet. 



100 to 150 

 feet. 



stand. 



IB 



10 

 21 



12 

 10 



2.35 

 2.53 



2.32 



1.32 

 1.30 



1.51 

 3.30 





0.40 

 .48 



.41 



Old cutting. 



3A 



0.7S 

 .91 



3b 



cutting. 

 Do. 



6 



Virgin. 













Note.— All plots receive at least half of full sunlight; all on level sites. 



Table 9. — Frequency of seed crops and their relation to reproduction (sample 



plots 3 A and 3B). 



Year. 



Seed crop. 



Number 

 of seed- 

 lings per 

 acre in 

 1920.1 



Year. 



Seed crop. 



Number 

 of seed- 

 lings per 

 acre in 

 1920.1 



1909 



Good 



0.5 

 4.5 

 13.2 

 

 37.0 

 

 35.0 



1916 

 1917 

 1918 

 1919 

 1920 

 1921 



Light 



8.4 



1910 











1911 



Light 





10,000 

 



1912 



Fair . . . 





1913 



Good .. 









1914 





Good 





1915 



Fair 













1 Number surviving in 1920, whose origin is credited to the seed crop indicated on the same line. 



