effect of fertilization on the nitrogen, active phosphoric acid, and active potash of a Lake Charles clay loam
Fraps, G.S. | Fudge, J.F. | Reynolds, E.B.
A study was made of the effect of fertilizers added during a period of 8 years in varying quantities and proportions up to maximums of 640 pounds of nitrogen, 960 pounds of phosphoric acid, and 512 pounds of potash per acre, upon the quantities of nitrogen, active phosphoric acid, active potash, and pH of a Lake Charles clay loam at Angleton, Texas. Nitrogen, active potash, and pH were not significantly changed, either in the surface soil or subsoil. Active phosphoric acid in the surface soil was markedly increased, but the increases accounted for only about 20% of the phosphoric acid added. The active phosphoric acid in the subsoils was increased significantly only in the plat which had received 960 pounds of phosphoric acid, and then the increase amounted only to 7 p.p.m. There was thus no significant penetration of the added nutrients into the low layers of soil, although some of the nitrogen after nitrification may have been leached out of the zone of soil sampled.Show more [+] Less [-]