1019] FIELD CROPS. 531 



tection against erosion from the high spring tides and winter storms. The 

 plant is said to give considerable promise for the future. 



Climatic control of the morphology and physiology of beets, H. K. Shaw 

 {Sugar [GMcag&\, 19 (1917), Nos. 10, pp. 387-391, figs. 10; 11, pp. 431-434, figs. 

 10; 12, pp. 479-486, figs. 27; 20 (1918), Nos. 1, pp. 23-27, figs. 3; 2, pp. 68-70, 

 figs. 8; 3, pp. 109-112, figs. 2; 4, pp. 150-154, figs. 4).— Observations by the 

 author during several years' work in breeding sugar beets are said to have re- 

 vealed numeroUs apparent vagaries In their morphological development, many 

 of which proved detrimental to the production of seed. 



A strong correlation between climatic conditions and morphological develop- 

 ment was noted and was seemingly substantiated by available data. Extensive 

 experimental work was planned to test the effect of environmental factors 

 upon the morphology and physiology of beets, with special reference to climate, 

 especially temperature and moisture. Field experiments were begun at Ogden, 

 Utah, In 1012, in winch 4 series of plats were planted at successive intervals of 

 .ili.Mit 8 weeks, so that the earlier stages in the development of the crown bud 

 rudiments might be exposed to progressively higher temperature conditions 

 with all their accompanying meterological factors. 



Different methods of planting were also adopted In order to modify the effects 

 of these factors and their relations to the bud development. In the first row 

 of each series the crowns of the mother beets were covered with soil to protect 

 them from late frosts and to protect the young buds from the intense heat and 

 actinism of the midday sun in semiarid regions. In the second row the devel- 

 oped buds were removed to insure the activity of the hitherto dormant bud 

 rudiments. The crowns of the beets in the third and fourth rows were exposed 

 to afford comparisons with those iu the first and second rows, respectively. 

 The effect of shade was ascertained by placing a canopy over certain portions 

 of the beets. An additional series was made up of selected beets from which all 

 visible buds and leaves were removed after robust rosettes of leaves had formed 

 un their crowns, thus leaving only bud rudiments that otherwise would have 

 remained dormant, but which, due to the stimulus of relatively high mean tem- 

 peratures of both air and soil and of a well-developed root system, were aroused 

 into active growth. The meteorological apparatus employed is fully described. 



During 1013 experiments were conducted at Jerome, Idaho, with beets placed 

 in cold storage to induce a rest period, siloed beets at Ogden being used as con- 

 trols. Additional tests with siloed beets were made at Brooklyu,-N. Y. f In 1916 

 and 1917. 



The methods of procedure of all the experimental work are enumerated in 

 detail, the meteorological and other data are recorded in tabular form, and the 

 results are discussed at some length. 



" The experiments described have shown a close correlation between climatic 

 conditions and the morphological development of beets, whether wild or in 

 cultivation. It would appear that climatic factors operating on the growing 

 point of the bud rudiments of beets, according as they cause a prolonged re- 

 straint of the physiological operations of those growing points or a stimulation, 

 determine the bud rudiments either reproductively or vegetatively. Any inter- 

 mediate stage between normal reproductivity and complete vegetativeness may 

 be induced, according to the degree and duration of the restraint. It would also 

 appear that other factors inducing a similar restraint of the activities of the 

 growing point will produce identical results. Among such factors are drought, 

 lack ofnutriment, and inhibitory pathological or physiological conditions. 



"Based upon these data, the following hypothesis is advanced: A relatively 

 prolonged period of restrained growth in the growing points of bud rudiments 



