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Meteorological data for stations where irrigation was not used—('ontinued.
Meteorological data for stations at which irrigation was practiced.
a Data for March to September.
GENERAL SUMMARIES OF DATA,
Table of general averages of agricultural and analytical data for the five years, 1900-1904.
General averages of meteorological data (May to October) for the five years, 1900–1904.
STATIONS WHERE IRRIGATION WAS NOT USED.
71.6 62.9 53.7
11.9 21.5 21.9 21.1 20.8 18. S 25.0 19.8 20.0
90 83 57 56 71 18 107 63
64.7 60.4 61.2 59.6
STATIONS WHERE IRRIGATION WAS PRACTICED.
78.7 73.8 63.8
a Three years' data.
It is not advisable to discuss each of the tables of the summary separately, as the purpose of the investigation will be realized by the study of the table of averages. The agricultural data show some very curious results. It is seen that in the five years the yields per acre at Washington, Blacksburg, Madison, Ithaca, Ames, Agricultural College, and Geneva are fairly satisfactory, being in each case over 12 tons. Two of the stations, namely, Lexington and Lafayette, show a yield of approximately half a crop only, and Raleigh, from which only two years' data were obtained, shows practically a complete failure of the crop, and is therefore excluded from the summary. Moreover, it must be remembered that the tonnage figures have been estimated in all cases upon the weights of beets from very small areas, and thus it is evident that these results may not be strictly accurate. It is, nevertheless, true that these data show with a considerable degree of accuracy the comparative yields at the various stations.
The practical failure of the crop at Raleigh appears to have been due more to the uneven distribution of the rainfall than to
other source, in so far as the meteorological data throw any light upon the subject. In so far as the possibility of producing a large crop is concerned, there is no reason to believe that the station at Raleigh would necessarily occupy such an inferior position.
PERCENTAGE OF SUGAR IN THE BEET.
These are by far the most important of the agricultural data collected, since the special object of the investigation was to consider the effect of the environment upon the content of sugar alone, and not upon the general composition of the beet. The stations are arranged in the table of general averages in accordance with the percentage of sugar, the lowest being placed first. First, attention should be called to the well-known fact that a phenomenally small yield or small-sized beets tends to increase in an abnormal way the percentage of sugar in the beet. The beet being a plant which by long continued selection and cultivation has formed a habit of producing sugar, tends to exercise that habit even under the most adverse circumstances. The habit of sugar forming, therefore, may be said to be a ruling passion in the beet, strong even in poverty, and the actual storage room of the small beet being limited, it is only natural to find it more fully stocked with the sugar produced. This point must be fully considered in comparing the sugar content of the beets produced at Lexington and Lafayette with those from the other stations. It is perfectly reasonable to suppose that had the crops at these stations been normal the percentage of sugar would have been greatly reduced. Any slight displacement, therefore, in the natural order in which the stations would have appeared (considering temperature and sugar content) does not in any way interfere with the general proposition which has been established throughout this long series of observations, viz, that temperature, or, in other words, latitude, is the most potent element of the environment in the production of a beet rich in sugar.
Again, Geneva, which not only produced the largest crop next to Madison, but also the richest beets, should, under normal conditions, have occupied the position held in the table by Ithaca, considering their relative temperatures and altitudes, but not their latitudes. Although Geneva is about 35 miles farther north, by reason of its lower altitude the average temperature for the five years is higher at Geneva than at Ithaca. Many modifying circumstances, which influence to a greater or less degree the effect of the temperature upon sugar production, have been active in the general problem, and are discussed under the following caption. These modifications, however, are of so slight a nature as not to decrease the value of the general conclusions.
The average temperature is given in the general table, both for the whole period of six months and for the three most important growing months—June, July, and August. There is a very marked relation between the average temperature and the sugar content of the beet, although, as has already been mentioned, there are some variations from the general rule, the several factors of the environment interacting on each other so as to modify these general relations. It is seen that, although Lexington is farther south than Washington, and thus would naturally have a considerably higher temperature, it is about 942 feet higher, and this altitude has a tendency to diminish the temperature. It must be remembered, however, that Washington, by reason of its propinquity to the sea, has a climate which is modified to a greater or less extent by the influence of the ocean, whereas Lexington has practically an intracontinental climate, being removed from all bodies of water, not even having the modifying influences of a river. This accident of situation is one of the circumstances explaining the slightly higher temperature of the Lexington station, and the fact that only half a crop was produced also tends to place the beets grown at Lexington in the relation to the Washington crop that theory would predict, despite the slight difference in percentage of sugar in the beet of one-tenth per cent in favor of the Washington crop.
The most conspicuous departure from the general rule is shown in the data from Ithaca. The mean temperature at Ithaca is less than at any other of the collaborating stations, being 0.2° F. less than at Agricultural College, Mich., and 1.9° less than at Geneva, only 35 miles north. The inferiority of the beets grown at Ithaca is due to some cause which does not clearly appear in the agricultural and meteorological data. Numerous modifying conditions may, however, be suggested. The inferior size of the beet grown at Ithaca, the small crop, and the markedly low purity are to be kept in mind, as well as the inferiority in sugar content. The comments of Mr. J. W. Gilmore, of the Ithaca Station, made in response to a letter from the Bureau of Chemistry calling attention to the peculiar relations apparently existing between the beets grown at Ithaca and at Geneva, are of general interest and are submitted in part as follows:
Your letter of recent date regarding the factors which influence the quality of sugar beets here in Ithaca has been received and I have given the matter considerable attention, inasmuch as I have been much interested in the points which you bring out. I have observed for some time that better sugar beets were grown north of us, both at the north end of Cayuga Lake and also between Cayuga and Seneca lakes in the vicinity of Geneva, than in the vicinity of Ithaca. I refer both to the sugar content and purity as well as to the tonnage. While I have never studied this matter in detail, yet I believe the following factors are influential in bringing about such conditions:
In the first place, the soil at the north end of Cayuga Lake and in the vicinity of Geneva seems to be better adapted physically for sugar beets than it is here. Several years ago, when the Binghamton sugar factory was in operation, a number of contracts for sugar beets were let in this locality and they proved to be practically unprofitable, while the beets have been grown for the factory successfully in the neighborhood of Union Springs and farther north. I think the physical condition of the soil of this locality and north of us is quite an important factor in the development of better beets in the vicinity of Geneva.
In the second place, I believe there is more sunshine during the growing season in the vicinity of Geneva than there is here in Ithaca. The lack of sunshine here is very noticeable throughout the entire year, but especially in the winter time. It may be, too, that Geneva is far enough north to enable them to have sunshine during a longer daylight period while the beets are growing than at Ithaca.