KEPRODUCTIOE' OF WESTERIST YELLOW PUsTE. 



33 



Soil No. 28. 



desckiption of soil. 



Reddish-clay loam to clay surface soil 6 to 15 inches, coasisting mainly of 

 colluvial wash resting either upon the bedrock or upon a very thin layer of 

 stiff, red, residual clay. Soil texture and structure very similar to soil 20, 

 but soil layer is less in thickness. Smaller percentage of gravel, surface slightly 

 more compact, and not as well aerated as soil 9. 



RELATION TO YELLOW-PINE GROWTH. 



Percentage of germination and survival may not be as high as on more 

 stony and gravelly soils, but increment may be fair. The downward develop- 

 ment of roots is limited to shallow depths. 



PLOT 3b. 



The soils of this plot belong in the upper part of the Coloradan Soil Zone, to 

 the Tusayan types, and in geologic classification to the basalt group. The mineral 

 bases of the soil divisions of the plots are from the same rock source and 

 probably essentially the same in chemical character and also the same in 

 physical character of the soil profile as in Plot 3a. There is a slightly larger 

 proportional area of extremely stony soils, 12 and 6, and a somewhat smaller 

 area of nearly stone-free soils. 



Table 10. — Seedtitiff soil survey. 



And=^ Andropogon scoparius, Ann^Annuals, 'Bl^BlepJiarotieuron triclwlepis, C^Ceano- 

 thus fendleri, 'ET=Erigeron divergens, W=F€stuca arisonica, Lot=Lofu-s wriglvtii, 

 Lup=i>!<iPWMS httlii, 'M^=MuMen'bergia montana, 'Paxi.= Paiiicnim sp., Sit=>S'#anto7i 

 molle and S. irevifoliunv, Vic=Ficto americana. 



1. Sample plot 3a (August-September, 1920). 



Plot.i 



H8 



H9 



HIO 



0.28 acre. 



K8 



LI 



L8 



L9 , 



0.4 acre. 



A5. 

 B2. 

 C5.. 

 H6. 

 J4.. 



Vegetation in order of abun- 

 dance. 



Soil No. 12, roc1<: outcrop: 



And, C.M, Lot 



M, And, Lot, C, F 



And, Lot, C, Pan, M.. 



Total-... 

 Per acre . 



Soil No. 24, stony clay: 



M,Lot,r 



M,r 



Lot,M,r 



F,M, Vic 



Total.... 

 Per acre . 



Soil No. 9, gravelly clay: 



F, M, Lup , 



M, Bl, F, Vic. Lup.. 



F, Sit, Lup, Ann 



M,F,B1 



M, Bl, Vie, F........ 



Num- 

 ber of 

 seed- 

 lings .2 



343 



Plot.i 



K 10 



K4 



0.7 acre. 



Dl. 



El. 

 E5. 



C3 



F6 



H4 



H5 



15 



0.5 acre. 



Vegetation in order of abun- 

 dance . 



Soil No. 9, gravelly clay — Con. 



M,Bl,Vic,F 



F,M,Bl,Lup 



Total.... 

 Per acre. 



Soil No. 20, fine clay: 



F, Lup, M, Vic 



I Seedlings 

 mainly in 

 brush or old 

 road. 



Total.... 

 Per acre - 



Soil No. 28, shallow clay: 



M, F, Vie, sparse 



F, Lup, Vic 



F,M,Bl,Sit 



F (nearly pure), M, Lup. 

 F (nearly pure), M, Vic.. 



TotaL... 

 Per acre. 



Num- 

 ber Of 

 seed- 

 lings .a 



96 

 1.37 



1 AU plots contain 0.1 acre, excepting H 8, which is 0.08 acre. 



* Only seedlings over 2 years old counted. Nearly aU are 4 years or over. 



90i°— 23 3 



