FORAGE CROPS IN NORTHERN GREAT PLAINS. 



Ardmore, and Belle Fourche, and the lowest at Moccasin. Absolute 

 maximum temperatures of 110° F. have been recorded at Redfield, 

 Dickinson, Mandan, and Edgeley. The lowest temperature recorded 

 is —57° F. at Havre. At the other stations the absolute minimum 

 temperature ranges from —34° to —49° F. The average number of 

 days between killing frosts ranges from 106 at Dickinson, N. Dak., 

 to 137 at Belle Fourche. The shortest season, 47 days, is recorded 

 at Dickinson and the longest, 173 days, at Williston, N. Dak. The 

 average date of the last killing frost in spring occurs between May 8 

 and May 27, and the first in the fall between September 9 and Sep- 

 tember 27, thus giving a range of nearly four weeks in growing season 

 between stations. The latest killing frost in the spring is reported 

 as occurring on June 25, at Dickinson, and the earliest killing frost 

 in the autumn on August 9, at the same station. At all these sta- 

 tions there is a wide range between the shortest and longest growing 

 seasons reported. The average seasonal wind velocity ranges from 

 4.5 to 6.8 miles per hour. 



Table 7. — Summary of climatological data for all stations in the northern Great 

 Plains region from which forage-crop data are reported. 



[Data marked with a star (*) are from the records of the United States Weather Bureau, those marked 

 with a dagger ($) are from the records of the Biophysical Laboratory of the Bureau of Plant Industry, 

 and those marked with both these signs are from both these sources. Data marked with a double dag- 

 ger ($) are from North Dakota Experiment Station Bulletin 158, being taken in part from records made 

 at Fort Buford, Williston, and Williston substation in North Dakota. The seasonal data are for the 

 months of April to September, inclusive.] 



Stations. 



Alti- 

 tude. 



Precipitation. 



Aver- 

 age an- 

 nual. 



Aver- 

 age. 



Per- 

 cent- 



of an- 

 nual. 



Annual. 



High- 

 est. 



Low- 



Sea- 

 sonal 

 evap- 

 ora- 

 tion. 



Ratio of 

 seasonal 

 precipita- 

 tion to 

 seasonal 

 evapora- 

 tion. 



Seasonal tempera- 

 ture. 



Mean. 



Mean 

 maxi- 

 mum. 



Mean 

 mini- 

 mum. 



Redfield 



Havre 



Moccasin 



Dickinson 



Mandan 



Williston 



Hettinger 



Edgeley 



Sheridan 



Belle Fourche 

 Ardmore 



Feet. 

 1,295 

 2, 600 

 4,300 

 2,543 

 1,750 

 1,875 

 2,675 

 1,468 

 3,790 

 2,850 

 3,567 



Inches. 



*20. 33 



*tl3. 27 



♦$16. 52 



*15.41 



♦$17.04 



±14. 76 



♦14. 52 



♦17. 57 



*14. 43 



$15. 46 



fl6. 69 



Inches. 



♦15. 62 



*t9. 77 

 *fll.99 



♦12. 04 

 *tl2. 99 



$11.12 

 "*11.86 



*14. 51 

 ♦9.36 



fll. 74 



t!3. 25 



76.8 

 73.9 

 72.6 

 78.1 

 76.2 

 $75. 3 

 81.7 

 82.6 

 64.9 

 75.9 

 79.4 



Inches. 



*30. 76 



♦$25. 67 



*f23. 76 



*22. 74 



♦$30. 92 



$23. 25 



*22. 35 



*27. 45 



*22. 51 



$25. 89 



f30. 41 



Inches. 



*11.98 



*f6. 76 



♦$9. 90 



♦8.37 



♦$10. 31 



$7.37 



*7.37 



*10. 41 



♦7.98 



|6.64 



fl2. 78 



Inches. 



$35. 8 

 t33.4 

 f32.9 

 t34.8 

 $$33 

 t32.5 

 $29.2 

 |36.2 

 t36.7 

 f37.7 



1 to 4. 

 1 to 2. 8 

 1 to 2. 7 

 1 to 2. 7 

 1 to 3.0 

 lto2.7 

 1 to 2. 

 lto3.9 

 1 to 3.1 

 1 to 2. 8 



°F. 

 *61 



t58 

 $55 

 ♦58 

 *59 

 ♦58 

 *58 

 $58 

 ♦57 

 $61 

 $61 



°F. 



'/•'. 



$72 



$68 



*72.6 



*71.2 



*71 



$72 



$71 



*72 



$74 



$75 



$45 

 $41 

 *43 

 ♦47 

 ♦45 

 $44 

 $45 

 *43 

 t47 

 $47 



Stations. 



Absolute tem- 

 perature for 

 station. 



Maxi- 

 mum. 



Mini- 

 mum. 



Killing frost. 



Average date. 



Last in 

 spring. 



First in 

 autumn. 



Latest in 

 spring. 



Earliest 



in 

 autumn. 



Growing season. 



Aver- 



Short- 



Long- 



age. 



est. 



est. 



Days. 



Days. 



Days. 



♦136 



*83 



*172 



*$125 



*$83 



♦$152 



$125 



$83 



$150 



♦106 



4=47 



*155 



*$130 



♦$98 



*89 



*$170 



*124 



♦173 



*113 



♦92 



♦129 



*125 



*85 



♦143 



♦123 



♦100 



♦156 



$137 



$119 



$171 



$135 



$121 



$149 



Aver- 



sonal 

 wind 

 veloc- 

 ity per 

 hour. 



Redfield 



Havre 



Moccasin 



Dickinson 



Mandan 



Williston 



Hettinger 



Edgeley 



Sheridan 



Belle Fourche 

 Ardmore 



♦110 



*$108 



$103 



*110 



♦$110 



*$109 



♦$106 



tllO 



*105 



$109 



$103 



♦May 14 

 *$Mayl7 

 $May 18 

 ♦May 26 

 ♦$May 12 

 ♦May 17 

 ♦May 27 

 ♦May 18 

 ♦May 20 

 $May 12 

 -34 $May 8 



♦Sept. 27 

 ♦$Sept.l9 

 $Sept. 20 

 ♦Sept. 9 

 '$Sept.l9 

 ♦Sept. 18 

 ♦Sept. 17 

 ♦Sept. 20 

 ♦Sept. 20 

 $Sept. 26 

 $Sept. 20 



♦June 21 

 ♦$June 3 

 $June 2 

 ^June 25 

 ♦$June 7 

 ♦June 16 

 ♦June 16 

 ♦June 9 

 ♦June 6 

 $May 31 

 $May 20 



♦Sept. 9 

 ♦$Aug.25 

 tAug. 24 

 ^Aug. 9 1 

 ♦$Aug.23 

 ♦Sept. 3 

 ♦Aug. 28 

 ♦Aug. 20 

 ♦Aug. 25 

 $Sept. 14 

 $Sept. 8 



Miles. 



$5.4 

 "6.5 

 -6.7 



•6 

 $$6.8 

 $6.4 

 -6.6 



-4.5 

 $6.6 

 $5.3 



1 July 19 is given in one table. 



82537°— 24f 2 



