1520 



ENCYCI.OPKOIA OK I'UACTICAT- I IDHTU'C l/Pli;!-: 



cycles of 3 years, then a longer one of 

 about 9 or 11 years, and still a greater 

 cycle of 30 to 35 years, the last being 

 more clearly pronounced; but no general 

 agreement has yet been reached regard- 

 ing them. 



Studies of the mean daily, mean 

 monthly, and mean annual temperatures, 

 while important in themselves, give us a 

 nearly unchangeable factor, and one not 

 particularly interesting or striliing in its 

 features. 



The factor that is the most important, 

 in my opinion, is the daily minimum tem- 

 perature, which is as a rule notliing more 

 than the lowest night temperature. The 

 night temperatures explain the interest- 

 ing cause why the crops do not grow and 

 why the season is delayed. The days may 

 be warm and bright, but vegetation as a 

 rule will not flourish as long as the nights 

 continue abnormally cold. 



To the above statement regarding the 

 importance of the daily minimum tem- 

 perature in its relation to plant growth 

 it mi.ght also be added that the duration 

 of the minimum temperature, if it is suf- 

 ficiently low to injure vegetation, is a 

 most important factor. If a critical tem- 

 perature continues for only a very short 

 time, as sometimes happens, little or no 

 damage may occur, while a longer period 

 of duration may produce disastrous re- 

 sults. 



Mr. Reeder further states: 



It appears from climatological data 

 * * * that the springs of the past 10 

 years experienced quite marked temper- 

 ature departures from the normal. The 

 most interesting as well as the most im- 

 portant question to be answered is. How 

 long will the cold period last? Unfortu- 

 nately our climatological data do not 

 cover a sufficient length of time to enable 

 us to work out the number of years to 

 each cycle. While the records show 

 periods of both mild and cold springs for 

 the 30 years, the change during the last 

 20 years from mild springs to unusually 

 cold springs is not only of marked inter- 

 est to the cllmatologist but bears rather 

 more serious import to the orchardists, 

 whose earnings have been affected, and 



wlio aic of course interested in the ques- 

 tion of whether mild springs will ever 

 come again. 



In connection with the article by 

 Reeder, data from several representative 

 points relating to spring frosts in Mis- 

 souri are presented which show that at 

 those points the average date of the last 

 killing frost in the spring during the 

 years 1901 to 1910 was 11 days later than 

 it was during the 10 years preceding 1901. 



Data of flic Arknus.as Portion of the 

 Kegion 



An examination of climatological data 

 from northwestern Arkansas during the 

 period 1901 to 1910 shows an advance in 

 the average date of last killing spring 

 frost at some points but not all. For in- 

 stance, the corresponding average date at 

 Fort Smith for the years 1901 to 1908 was 

 eight days earlier than for the period 

 1891 to 1900. The difference in variation 

 between frost dates at Forth Smith and 

 points farther north may be due to the 

 influence of the Boston mountains in pro- 

 tecting the portion of the Ozarks south 

 of them from the effects of the cold trans- 

 continental storms which occurred during 

 those years in their transit from west to 

 east. Moreover, many of the orchards in 

 northwestern Arkansas have relatively 

 high locations, with better atmospheric 

 drainage than those where the elevation 

 is the same or nearly the same as the 

 surrounding country. 



VarietiPS firown 



On account of the large number of va- 

 rieties grown in this section, discrimina- 

 tion is necessary in selecting sorts for 

 discussion. Space limitations forbid them 

 all ; but as far as possible the varieties 

 included consist (1) of the sorts which 

 are widely grown; (2) of those now 

 grown only to a limited extent but which 

 appear to be of such value as to warrant 

 more extensive recognition; and (3) cer- 

 tain fault.v varieties which are considered 

 likely to be planted without a full knowl- 

 edge of their tendencies. 



Ada Red 



This variety was originated about 1890 

 near Springtown, Arkansas, by Mr. A. G. 



