58o 
Journal of Agricultural Research 
Vol. V, No. 13 
Lime has not given material gains with cotton in either test, owing 
undoubtedly to the physical condition of this land and the large amount 
of lime carried by the two soils. As a general rule, the minerals which 
carry lime in the Piedmont soils are more susceptible to chemical and 
physical decomposition than those found among the fields of the Atlantic 
Coastal Plain. 
Table V gives the average yield of cotton on Norfolk fine sandy loam 
at the Edgecombe Substation with seven years' fertilization. 
TabIv3 V.— Average yield of cotton on fields A and B with seven years' fertilization at 
the Edgecombe Substation 
Average yield of seed cotton 
per acre. 
Average in¬ 
Treatment. 
Field A (1903, 
1904,1906, and 
1908.) 
Field B (1905, 
1907, and 1909.) 
crease per acre 
due to fertilizer. 
Control. 
Pounds. 
I, 030 
1,215 
1,076 
Pounds . 
429 
^059 
873 
Pounds . 
Nitrogen and potash. 
376 
Phosphoric acid and potash... 
217 
Nitrogen, phosphoric acid, and potash... 
i> 193 
I, 022 
348 
Nitrogen and phosphoric acid. 
1, 108 
717 
167 
Lime. .. 
1, 061 
5 10 
62 
Lime, nitrogen, phosphoric acid, and potash. 
I, 024 
499 
Table V gives the results of fertilizer tests which are in marked con¬ 
trast to those obtained from the Cecil series of the Piedmont Plateau. 
Fertilizer mixtures carrying potash give the most marked yields; in 
fact, nitrogen and potash give greater returns than the three fertilizer 
constituents. 
Lime in connection with the three fertilizer elements has produced 
decided gains. The physical condition of this soil is surely as good as 
that of the Cecil sandy loam at Raleigh, and the amount carried by the 
soil is quite sufficient to furnish this constituent as a plant food for a 
number of years to come. The petrographic examination of the Norfolk 
soils gives epidote as the only lime-bearing mineral of any consequence. 
It would seem therefore that lime carried in this form is of doubtful value 
in performing its functions in the soil. 
The amount of potash here is. even greater than that found in the 
sandy loam at Raleigh, yet potash seems to be the limiting element on 
this field. Weathered orthoclase and microcline furnish practically all 
the potash supply of this soil, while biotite and muscovite micas are 
much more abundant in the Cecil series. 
Another interesting point brought out in these experiments is in 
regard to the phosphoric-acid content of the three fields. In the Edge- 
