8 CIRCULAR 137, U. S. DEPARTMENT OF AGRICULTURE 
TABLE 3.-—Chemical analyses of crotalaria grown at the Florida Agricultural 
Experiment Station, Gainesville, Fla. : 
Carbo- 
Species Water Ash Fat Protein hydrate 
Fiber 
Per cent | Per cent | Per cent | Per cent | Per cent | Per cent 
@ERTIS APA TI OC TAS 1S ote oe per ere 9.15 4. 73 4. 02 21. 38 41. 87 18. 85 
Os pectalbbilis 72 Soe ve eee ee ee 9. 70 6. 40 3. 48 15. 00 49. 62 15. 80 
1 The plants were 2 feet high when cut for analysis. 
In studies by W. A. Leukel and reported by Stokes (7/4), young 
plants were found high in percentage of hydrolyzable carbohydrates 
and exceptionally high in total nitrogen. As the plants grew older 
the proportion of cellulose and lignin increased. 
It is evident that these facts must be given consideration in deter- 
mining the stage of development and amount of plant growth best 
suited to meet the needs of the crop to be fertilized or benefited. 
As stated by Leukel, Barnette, and Hester (7) : 
If a rapid accumulation of nitrates is desired, as in the case of vegetable 
crops, then the crotalaria plant should be incorporated with the soil in its 
early growth stages. If, on the other hand, a retarded accumulation of nitrates 
is desired, so that the crop or tree may make use of the nitrogen in the spring 
months, the plant should be in an advanced stage of growth and dry before it 
is incorporated with the soil. 
LONGEVITY AND HARD SEED 
Crotalaria seed in storage under favorable conditions has a long 
period of viability. Seed of several species 10 years old has been 
germinated, and it is probable that the seeds of other species have a 
similar life period. Under field conditions viable seed may remain 
in the ground for at least one season before germinating. This 
delay in germination is made possible by the presence of seed that 
has an outer seed coat impervious to moisture. Whether or not 
this seed will remain in the soil more than one season has not been 
determined, but it seems probable that such is the case. Viable seed 
that does not germinate promptly is commonly referred to as hard 
seed. In Table 4 is given the percentage of germination and hard 
seed in several species of Crotalaria. The seed referred to as scari- 
fied was placed on an emery board and rubbed for a few seconds with 
sandpaper. 
TABLE 4.—Germination and hard seed in Crotalaria species as shown by a 
10-day germination test 
Germination Hard seed 
Accession No. Name N 
: ot scar- : Not scar- 
Searified ified Searified ified 
Per cent | Per cent | Per cent | Per cent 
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See 36969seaee 35 She ane erieeen a @Sretusass sees = ee 38 0 52 98 
SeePeel 16406222 a. 2s. See Sie C@ispectabilis= = = 45 8 43 80 
Bi @ el 584325222 eto baa eer O@Nstriatancww ose eae 50 18 25 €2 
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