ALFALFA ROOT STUDIES. 
11 
The analyses showed a high percentage of lime, especially at a 
depth of 1 to 5 feet. The surface foot is a fairly open black silty clay 
loam. At a depth of 1 to 4 feet it consists of a high percentage of 
fine soil particles and is fairly compact. A silty loam of a soft, shaly 
nature occurs at a depth of 4 to 5 feet. From 5 to 10 feet the soil is 
a clay that is apparently easily penetrated by alfalfa roots. 
Investigations indicate that the type of root growth is pretty defi- 
nitely determined during the first few months, and for this reason 
a summary of temperature and precipitation records is presented as 
indicating in a general way the moisture available to the plant 
(Table 4). 
Table 4.- 
Summary of precipitation and temperature record.* 
N. Dak., from April, 1916, to March, 1917. 
at Red field, 
(trowing season, 1916. 
Items of comparison. 
Apr. May. June. July. Aug 
Fall conditions, 
1916. 
Sept. Oct. Nov 
Winter conditions, 
1916-17. 
Dec. Jan. Feb. Mar 
Total precipitation, inches.. 1.11 
Departure from normal, 
inches —.65 
Average temperature, °F... 43 
Departure from normal 
5.13 
+2.22 
55.6 
-1.7 
3.56 
+.82 
62.4 
-3.2 
2.01 
-.95 
78.8 
+8.5 
5.19 
+1.97 
70 
1.42 
-.45 
58.2 
0.55 
-.8 
43-8 
3 
2.13 
0.4+1.75 
30. 
r;- 
+2.09 
5 
+ .3; 
4 
-8.4 
2.25 
+ 1.6 
23.9 
Total precipitation, inches. . 
Departure from normal, 
inches 
17.00 
+3.41 
1.97 
-1.65 
7.55 
+5.81 
These data show that the season was favorable for alfalfa growth. 
There was an abundance of rainfall and cool weather in early spring 
and as late as early July. Drought then became gradually more 
pronounced, and unusually high temperatures prevailed until the 
middle of August, when rains occurred, resulting in late summer 
and fall growth. It would appear that conditions were favorable 
for a well-established root system in early spring an< 
during the 
summer. 
DIFFICULTIES ENCOUNTERED IN GETTING COMPARABLE DATA. 
The chief difficulty encountered in obtaining comparable data on 
root systems in old fields of the less hardy alfalfa varieties and 
strains under the more severe environmental conditions is in making 
proper allowance for the doubtless accentuated growth of the sur- 
viving plants. The more susceptible plants having been winter- 
killed, the data obtained are from the more hardy individuals that 
have been given more room, permitting a greater root growth. In 
these studies at Redfield it was recognized that this thinning of 
stands and its effect on root growth was a factor that must be taken 
