Alfalfa. 
15 
LI' b0t i ® ln a show ca < se > exposed to a strong light and to all 
t e changes of temperature for five seasons in Colorado; when ten 
years old showed a germination of 72 per cent and when 16 years old 
a germmation of 63 per cent. The conditions under which thTs sam- 
ple has been preserved, especially during the first.six years, were less 
t A f b e f S r th e Preservation of its vitality than would ordinarily be 
t a e - S ° 1 th ' nl ? saf e to conclude that the limit for the vitality 
good, mature alfalfa seed exceeds 16 years. 
T ^e screenings, as will be seen by referring to the tables, stand in 
the same relative order of vitality that they did ten years ago. The 
deterioration, however, is very marked for all of them. The screen¬ 
ings jotted badly m 1896, worse in 1900 and still worse in 1906. 
L-i • dl? eXp f!^® ntS 1896 as man y as per cent of them rotted 
w i e m those of 1906 as high as.86 per cent of the same sample rotted. 
ave previously stated that bright, vigorous sprouts were des¬ 
troyed by coming m contact with the rotting seed and owing to this fact, 
1 doubt whether any plants would have survived, had the seed been 
used for actual planting. I endeavored to prevent the rotting bv 
wetting the upper piece of blotting paper with a solution of bichloride 
of mercury but when I stopped the rotting I practically stopped the 
sprouting. My solution was evidently too strong. I also made sepa¬ 
rate tests on samples No. 7, 8, 9 and 10 by first soaking them in pure 
water for two and a half hours and then for forty minutes in the bich¬ 
loride solution; this prevented the rotting but evidently injured the 
seed asi the results clearly show, of No. 7, 10 per cent, of No. 8,1 per 
cent of No. 9, 4 per cent and of No. 10, 3 per cent sprouted. Some 
of these sprouts were not strong but they were bright and healthy 
looking, they did not rot like the others. 
I call especial attention to sample No. 12 in the series of 1906 
because it shows how different lots of this seed may vary. This 
sample was obtained in 1905 as a sample of prime, fresh seed, but the 
best of the seeds were small. It required 288,267 of them to make a 
pound, whereas, of No. 9, first class screenings, it required 266,233 seeds 
to make a pound. Only 42 per cent of No. 12 were good, bright 
seed and only 10 per cent of the sample could be classed as 
good, bright, plump seed, and these 10 per cent were smaller, actu¬ 
ally weighed less, than the average seed of sample No. 1. The 
Ti,^ e L Cen ^ were small, green or brown and many of them shriveled, 
inis 58 per cent would have been removed by proper cleaning. The 
results of the sprouting experiments indicate this clearly for 79 per 
cent of No. 9 sprouted when the seed was three years old and only 
67.5 per cent of No. 12 sprouted when theseed was two years old. I may 
urt_ er remark that this sample, No.12, rotted badly showing that the 
rotting is due, as previously suggested, more largely to the sample 
than to its age. 
The Size and Length of Alfalfa Roots. —There is no subject on 
i/\# reater variet y of statements can be found than on this, 
lhe alfalfa root system as it develops in our soil is very simple as 
shown by the illustrations in Bui. No. 35. It consists of a tap root 
