68 



BULLETIN 1039, U. S. DEPABTME:N'T OF AGEICULTUEE. 



less, while the 15-poimcl rate yielded an average of 2.5 bushels per 

 acre less than the 30-pound rate. The best rate of seeding for irri- 

 gated flax on a clean, well-prepared seed bed apparently is about 

 30 pounds per acre, but under less favorable conditions more seed 

 might be desirable. 



DATE-OF-SEEDING EXPERIMENTS. 



Damont flax was grown in date-of-seeding experiments from 1916 

 to 1919, inclusive. Because of seasonal irregularities, especially 

 spring rains, it was not possible to sow the flax on the exact dates 

 planned. Seedings were made on three dates in 1916 and on five 

 dates during each of the other three years. The experiment usually 

 was conducted in duplicate. Good yields were obtained each year. 

 The yields are shown in Table LII. 



Table LII. — Yields of Damont flax grown in date-of-seeding experiments on ir- 

 rigated land on the Belle Fourche Experiment Farm, 1916' to 1919, inclusive. 







Yields per acre (bushel 



s). 



Date seeded. 



1916 



1917 



1918 



1919 



Average.' 





1916 to 

 1919 



1917 to 

 1919 



Aprill5to23 



8.4 





23.7 

 24.9 

 23.2 

 20.4 

 14.6 



13.4 

 13.0 

 12.5 

 12.1 

 12.1 







May 1 to 8 



16.9 

 12.3 

 14.2 

 10.7 

 6.3 





IS. 3 



May 15 to 26 



11.6 

 12.5 



14.9 



14.8 



16.0 



June 1 to 10 



15.6 



June 15 to 20 



12.5 



June 30 





















The highest yield was produced by the latest date of seeding in 

 1916, the earliest date in 1917 and 1919, and the second earliest date 

 in 1918. The results are somewhat inconclusive, but in general early 

 seeding is somewhat more favorable for flax. The highest average 

 yield for the 3-year period from 1917 to 1919, inclusive, Avas obtained 

 from the seeding of May 1 to 8. The later dates of seeding produced 

 progressively lower yields. Fair yields of flax from late seeding 

 may be obtained in some years. The seeding of June 30, in 1917, 

 was fully matured, but yielded only 5.3 bushels per acre. The flax 

 was damaged considerably in irrigating, however. When possible, 

 flax probably should be sown on irrigated land at Newell not later 

 than the first week in May. 



LATE IRRIGATION EXPERIMENT. 



Irrigation of flax after it is in full bloom has been supposed to be 

 detrimental, as it causes a renewed or second blooming and delays 

 the maturity of the seed. In 1916, a single twentieth-acre plat of 



