54 Richard H. Boerker 
loam, four in sand, and four in gravel. It is significant to note 
the large number of species in this table that germinate well in 
the gravel. 
On pages 52 and 53 are given the germination curves of Pinus 
ponderosa (S. D.), Pinus contorta, Pseudotsuga taxifolia (N. 
M.) and Pinus ponderosa (N. M.). These curves show that the 
gerinination usually begins earlier in the sand or gravel, that the 
curve rises more rapidly for these soils and that the germination 
per cent. is usually higher. 
Table IX gives the results for the Pacific coast species. Out 
of 9 species, two germinated first in the loam, the others ger- 
minated first in either the sand or gravel. Three had longest 
‘germination periods in the loam and six in either the sand or the 
gravel. Only one species, Libocedrus decurrens, showed the 
highest germination per cent. in the gravel, while six species 
germinated highest in the sand. 
On page 55 are given the germination curves of Pinus pon- 
derosa and Pinus jeffreyi both from California. These curves 
show substantially the same facts as those for the Rocky Moun- 
tain species. These curves show that Pinus ponderosa does not 
germinate so well on gravel as does Pinus jeffreyi a fact which is 
significant when it is remembered that the latter will. grow on 
much poorer soil than the former. 
TABLE IX 
Tue Errect or Soil Texture oN GERMINATION 
Pacific Coast Species 
Loam Sand Gravel 
Species gu ldo | daulUa ae duluoo 8 
ae ae rae mao | aie ae aie! liga =e 
ins. pondeyosan(Calits) eee eee 42 | 67 | 61.0] 20 | 82 | 68.0) 30 | 30 | 17.0 
UEC ICUS) J CHIL EN LER eRe aE ee te reer SN 7 | BBO AY KO) | SO] BO || GO|) TO-© 
Binuslanvvertvang ne eee 1) | SO a5 G2 uO |) OO) exo) | 8 | O.@ 
AWOTES. TOOTBYLED S060 6 285 ols bo ob be 44 | 52 | 18.0] 96 2 | 3.0) 50 | 48 5.0 
Libocedrus decurrensi,... 6.5 eno. 730) I 7 || OSLO, AS || GS acess! BS |) SB || aa, 
Sequoia washingtoniana........... LO) | cS 720), 16) 246.5!) 272 Te .0s5 
Wsuzasheierophylla ee eee | GS) ae | Oss Aad eel GO |B |) we 
IVE SHUTABSOS sg conn bse bene oaans 22 | 60 | 22.5) 18 | 64 | 31.0) 18 | 64 | 24.5 
IE OV CXHOCCUGENLOL IS a et eee — | — | — | — | — | — | mY] — J — 
Pseudoisuga taxtfolias. >... 4... 22-| 28 | 6.0] 38 | 44 | 5.0] 36! 48 | 6.0 
