36 CIRCULAR 863, U. S. DEPARTMENT OF AGRICULTURE 



remaining on the surface after 8 or 9 years' growth in a seed- 

 producing stand. During warm moist weather conditions, the 

 leaf litter closely in contact with the soil decays to form a valuable 

 source of organic material for soil improvement purposes. Sericea 

 "manures" the land as it grows. 



The existence the year around of the protective surface mat of 

 leaf litter in perennial stands of sericea is of prime significance 

 to the soil conservationist. Once the layer of leaf litter has 

 been formed, there is scant possibility that sheet erosion can 

 occur. Similarly, runoff is greatly retarded as clear rainwater 

 filters down rapidly through the surface mulch and is quickly 

 absorbed. The woody stem residue, left on the field after com- 

 bine harvesting sericea seed, makes good mulch material for 

 road banks, galled spots, gardens and for composting. Conse- 

 quently, sericea has vast potentialities as both a protective and 

 soil improving conservation cover crop for beneficial use on 

 millions of eroded acres of open land, especially in the hilly 

 sections of the Southeast. 



SOIL IMPROVEMENT WITH SERICEA 



Sericea is a deep-rooted legume and under suitable conditions 

 the roots are well nodulated. The badly eroded soils throughout 

 the lespedeza area are very deficient in organic matter. In 1943, 

 at the Southern Piedmont Conservation Experiment Station, 14 

 experimental plots in sericea on Class III land contained 0.827 

 percent of organic matter. The same land still in sericea 6 years 

 later, contained 1.251 percent, an increase of 51 percent in con- 

 tent of organic matter. On the poorer Class IV land, the com- 

 parable figures for soil organic matter were 0.853 and 1.174 per- 

 cent, respectively, an increase of 37.5 percent. The nitrogen 

 content of the soils showed a corresponding increase. Two or 

 more cuttings for hay were taken each year from these plots of 

 sericea. 



An experiment designed to evaluate sericea as a soil improving 

 crop has been conducted at the West Tennessee Agricultural 

 Experiment Station at Jackson, Tenn. (22). One range of plots 

 on Lintonia silt loam soil was seeded to sericea in 1930. A hay 

 and a seed crop was usually harvested from the area each year. Be- 

 ginning in 1933, and each year thereafter through 1943, two plots 

 were plowed up and planted to corn. Corn was continued each 

 year on these plots. Table 8 shows the average yield of corn in 

 bushels per acre for the first through the eleventh year after 

 sericea. The average yield of unfertilized corn from a nearby 

 range for the same period was 17.5 bushels per acre with a 

 seasonal variation from 8.6 to 27.2 bushels. The data show 

 average corn yields of 70.3 bushels the first year after sericea. 



14 Gosdin, Gittis W., The Nitrogen Content, Carbon-Nitrogen Ratio, and 

 Organic Matter Content of Acid Soil as Influenced by Different Cropping 

 Systems on Classes II, III, and IV Land. (Unpublished Ms. Thesis, Univ. of 

 Ga., Agronomy Dept.) 1949. 



