14 
BULLETIN 883, IT. S. DEPARTMENT OF AGRICULTURE. 
slender-stemmed short-fiber types. For new breaking under semi- 
arid conditions the seed-flax varieties of the so-called Russian type 
are best adapted. Resistant varieties should not be held at a pre- 
mium under these conditions. 
Table IV. — Annual and average yields of fourteen varieties and strains of flax grown 
on plats at the Northern Great Plains Field Station, Mandan, N. Dak., during 1914, 
1915, and 1916. 
Variety. 
C.I. 
No. 
Yield per acre (bushelr). 
1914 i 
1915 2 
1916 2 
Average. 
Reserve 
Select Riga (N. Dak. No. 1214) 
Damont (N. Dak. No. 1215) 
Select Russian (N. Dak. N«r. 608) . . . 
Frontier ( N. Dak. No. 155) 
N. Dak. No. 1221 
N. Dak. Resistant No. 52 
Stepan (N. Dak. No. 1340) 
Fargo Common (N. Dak. No. 1133). 
Idaho Common 
N. Dak. Resistant No. 73 
Kazan (N. Dak. No. 1329) 
N. Dak. Resistant No. 114 
Frimost 
17.6±1.9 
17.6+0.4 
19.0±1.4 
15.6±0.5 
,15.4±1.2 
*16. 1+0.1 
15.0±0.3 
14.7±1.3 
13.9+0 
15.6+0.8 
14. 3 ±0.3 
12.3±1.4 
14.9-fc0.8 
14.4+0.1 
19.3±1.2 
19.3 + 1.3 
17.6±1.5 
20.3±1.8 
19.0±1.3 
16.7±1.4 
17.1 + 1.7 
16.9±1.1 
14.9±1.2 
13.4 + 1.3 
13.9*1.0 
13.5±0.9 
12.5+0.6 
9.8+1.3 
14.0±0.8 
17.0+1.4 
13.8±1.1 
16.9+1.0 
13.9±0.8 
16.8+1.0 
14.1±0.8 
16.7+1.2 
14.3±0.9 
16.2+1.1 
14.2±0.8 
15.7+0.9 
13.3-fc0.9 
15.1 + 1.1 
13.4+0.7 
15.0+1.1 
12.7±0.7 
13.8+0.8 
12.4+0.6 
13.8+1.0 
12.7+0.6 
13.0+0.7 
12.9+1.0 
12.9+1.1 
9.2+0.3 
12.2+0.7 
10.0+0.5 
11.4+0.8 
Average. 
15.5 
16.0 
14.8 
Variety. 
C.I. 
No. 
Yield of oil (per cent). 
Actual yield of oil per acre 
"(pounds). 
1914 
1915 
1916 
Aver- 
age. 
1914 
1915 
1916 
351.3 
383.7 
292.0 
346.9 
423.0 
293.8 
361.8 
333.1 
303.6 
288.3 
391.3 
313.9 
296.7 
400.5 
296.3 
322.8 
387.0 
288.3 
302.4 
341.6 
256. 2 
279.9 
344.5 
288. 9 
273.2 
298.0 
275.6 
296.2 
269.7 
258.3 
262.7 
283. 3 
237.5 
231.4 
303.6 
278.1 
277.4 
243.0 
177.7 
253. 5 
195.9 
192.4 
Aver- 
Reserve 
Select Riga (N. Dak. No. 1214) 
Damont (N. Dak. No. 1215) 
Select Russian (N. Dak. No. 608). . 
Frontier (N. Dak. No. 155) 
N. Dak. No. 1221 
N. Dak. Resistant No. 52. 
Stepan (N. Dak. No. 1340) 
Fargo Common (N. Dak. No. 1133) 
Idaho Common 
N. Dak. Resistant No. 73 
Kazan (N. Dak. No. 1329) 
N. Dak. Resistant No. 114 
Frimost 
35.64 
35.20 
34.00 
33.00 
34.40 
35.80 
36.00 
34.00 
35. 10 
33.90 
32.80 
33.60 
33.24 
31.44 
35.50 
39.14 
33.80 
34.42 
37. 64 
41.38 
35.67 
36.40 
35. 72 
35. 94 
36.40 
40.16 
34. 72 
35.70 
37.25 
37.75 
39.00 
39.75 
37.00 
36.25 
34.40 
38. 50 
38.75 
37.20 
33.40 
38. 50 
34.50 
34.35 
36.13 
37.36 
35.60 
35.72 
36.35 
37.81 
35.36 
36. 30 
36. 52 
35.68 
34.20 
37.42 
34.15 
33.83 
342.3 
354.6 
332.8 
331.2 
331.2 
332. 7 
300. 1 
304.4 
282.3 
274.7 
261.2 
271.0 
232.7 
213.9 
i Average yields from duplicated twentieth-acre plats. 
2 Average yields from fifty-fifth-acre plats replicated 5 times. 
If we compute the probable errors of the differences in these aver- 
age results and multiply them by 3, as is customarily done, we find 
that, of the fourteen varieties, C. I. Nos. 13 and 12 are the only two 
in the experiment which are significantly poorer in yield than C. I. 
No. 19, the highest yielding strain. Both of these, however, are 
significantly lower in yield than the six most productive varieties. 
Reserve (C. I. No. 19) proved its superiority under these condi- 
tions, as it has in numerous other experiments at other stations. 
Select Riga (C. I. No. 21), which has never been distributed commer- 
cially, gave practically the same results in the three years. With the 
