THE OZARKS 



1519 



The more important climatic factors 



limiting profitable fruit production may 



be stated as follows: 



The temperature factor. — (1) Excessively 

 low during the dormant period, causing 

 injury to fruit trees or buds; (2) ex- 

 cessively high during the dormant 

 period, causing buds to swell and be- 

 come tender, making them susceptible 

 to injury later even by seasonable tem- 

 peratures; (3) excessively low during 

 the blossoming period, resulting in de- 

 structive frosts, or sometimes in pre- 

 venting the pollen from germinating, 

 thus making it impossible for the fruit 

 to set; (4) destructive freezes subse- 

 quent to the setting of the fruit; (5) 

 probably in some instances excessively 

 high temperatures during the blossom- 

 ing period, causing interference with 

 the proper setting of the fruit. 



The moisture factor. — (1) Excessive rains 

 during the blossoming period, which 

 may wash away the pollen; (2) rains 

 or continuously damp, cloudy weather, 

 which prevent the pollen grains from 

 being properly freed for dissemination; 

 (3) rains that prevent the activity of 

 insects which bring about the cross- 

 pollination which is necessary with 

 some fruits: (4) excessive droughts, 

 which injure trees or buds; (5) occa- 

 sional precipitation in such excess as 

 to affect the healthfulness of the trees. 



The loind factor. — (1) So strong and con- 

 tinuous during the blossoming period 

 as to prevent the activity of insects 

 upon which pollinization often depends; 

 (2) causing damage to trees or fruit at 

 some period during growth; (3) in its 

 relation to the evaporation of moisture 

 and the serious results which may 

 follow, especially during protracted 

 droughts. 



The relative amounts of sunshine and 

 cloudiness and the intensity of the Sun- 

 shine are also potent factors in their 

 influence upon the behavior of varie- 

 ties. 



Data of the Missonri Portion of tlio 

 Regrion 



Mr. George Reeder, section director of 

 the United States Weather Bureau, sta- 



tioned at Columbia, Mo., has contributed 

 a valuable digest of some of the climato- 

 logical data from several points in Mis- 

 souri, from which the following quota- 

 tion is made:* 



Notwithstanding the supposition that 

 orchards may be more liable to injury 

 from late spring frost at the present time 

 because in many cases almost the entire 

 orchard blossoms at the same time, or to 

 the improved strain of fruit now grown 

 [the latter statement is much in doubt, 

 many authorities claiming that improved 

 fruit is no more sensitive to cold than the 

 varieties grown 30 years ago], the fact 

 remains that the springs of the last 10 

 years, and particularly the last five years, 

 averaged colder than those of the pre- 

 ceding 10 or 15 years, and this statement 

 is well supported by climatological data. 

 * * * in apparent substantiation of 

 the popular idea that "our climate has 

 changed." I would, however, earnestly 

 caution the reader not to be too hasty in 

 the conclusion * * * that the climate 

 of Missouri is undergoing a permanent 

 change. Meteorologists of the world gen- 

 erally agree, and the world's climatolog- 

 ical records show, that the climate is 

 practically unchangeable; that is to say, 

 permanent climatic changes are notice- 

 able, probably, only in geological units of 

 time. On the other hand, the records also 

 indicate that while weather may change 

 from day to day or from hour to hour, 

 there are certain changes that move in 

 cycles or oscillations, having uncertain 

 units of time. The cause of these cycles 

 or oscillations is not definitely known, but 

 it has been pointed out by one or two 

 authorities that the wet and cool periods 

 and the dry and warm periods on the 

 earth appear to correspond somewhat 

 with the periods of maximum and mini- 

 mum sun spots, which in turn are thought 

 to be due to changes in the sun's photo- 

 sphere. A few students of the subject 

 claim that these weather changes go in 



• Keeder. George. "Are the spiinprs colder 

 now?" Monthly Weather Review, vol. 38. No. 

 12, December, 1010. d. 18.34. See also "Late 

 spring frosts in relation to the fruit crop 

 of Missouri." in the Fourth Annual Report 

 ffiftv-thlrd meeting) of the State Board of 

 ITortlculture of Missouri. 1911, pp. lin-l.^l. 



