482 



AMERICAN BEE JOURNAL 



December 



extends to the leaves and stems. Ker- 

 ner sowed the seed of summer savory, 

 in an experimental garden at a height 

 of 7,100 feet above sea level, in the 

 Tyrol, and the plants developed col- 

 oring matter in extraordinary abund- 

 ance, and not only the leaves but the 

 stems became a dark violet. 



Red coloration is due to a liquid 

 known as anthocyanin. When this 

 liquid is acid it is red, but when alka- 

 line, blue. A red rose may be changed 

 to a blue one by dipping it in a weak 

 alkali, and again turned back to red 

 by dipping it in a weak acid. Over- 

 ton has shown by many experiments 

 that the production of red coloring 

 depends on three factors: intense 

 light, low temperature, and a cell-sap 

 rich in sugar. Cut stems of lilies and 

 other land plants would not develop 

 red coloration, when placed in solu- 

 tion, until 2 per cent of an invert 

 sugar (grape sugar) was added. Red 

 coloring appeared then in great 

 abundance. The large amount of red 

 coloring in Alpine plants is conclu- 

 sive evidence that they produce more 

 sugar than lowland plants, and they 

 would, therefoie, be likely to secrete 

 more nectar. 



Since, therefore, according to evi- 

 dence supplied by many investigators, 

 plants secrete a gi'eater amount of 

 nectar at a high than at a low alti- 

 tude, and since this view is substan- 

 tiated by the presence of a large 

 amount of red coloring matter, fur- 

 ther discussion of this point seems 

 unnecessary. We may accept it as 

 proven that a high altitude, up to at 

 least 7,000 feet, is favorable to nec- 

 tar secretion. 



Latitude and Nectar Secretion 



Let us next consider whether a 

 high latitude is favorable to an in- 

 ci eased secretion of nectar. With 

 the exception of a rarified atmos- 

 phere essentially the same conditions 

 as to a large amount of light and low 

 temperature prevail in northern as in 

 Alpine regions. The many hours of 

 daylight permit the plant to manutac- 

 ture food for a much longer time 

 than further south. Expe -iments in 

 illuminating plants with electric 

 lights show that they do not require 

 a rest at night, and that with more 

 light they can be forced to do more 

 work. In the spring and early sum- 

 mer, and in late autumn, the nights 

 are colder than the days. This is 

 often also true of nights in mid- 

 summer. "The north," says Sladen, 

 "is particularly well adapted for bee- 

 keeping, as the warm days and cool 

 nights favor nectar secretion, while 

 the long working day increases the 

 crop. In favorable seasons 200 

 pounds of clover honey per colony is 

 common near Lake Temiskaming. At 

 Roberval, on Lake St. John, Quebec, 

 an average annual colony yield of 

 200 pounds is obtained from alsike 

 and white clover." (In MS.) In the 

 cr.se of no honey plant is the effect of 

 latitude so well shown as in white 

 clover. In Michigan, Wisconsin and 

 southeastern Minnesota it is a very 

 reliable honey plant. (See American 

 Honey Plants, p. 277). A beekeeper 

 in Fillmore County, Minnesota, writes 



that a complete failure of white clo- 

 ver has not been known in that local- 

 ity for 20 years. It is a much better 

 honey plant there than in either Illi- 

 nois or Iowa, where good crops of 

 honey are secured on an average only 

 about 2 years out of 3. Farther 

 south, white clover is a very unreli- 

 able source of honey, although it may 

 occasionally yield a large surplus. 

 Undoubtedly the goldenrods are far 

 better honey plants in Canada and 

 New England than farther south- 

 ward. The wild raspberry in Michi- 

 gan. Hutchinson says, never fails to 

 produce honey, and he has seen bees 

 working well upon it, when the 

 weather was so cool that clover would 

 not yield a drop of nectar. No plant 

 was known to him which yielded more 



Field goldenrod. A species which blooms early 

 and does not yield nectar freely 



honey in a season than great willow- 

 herb (Epilobium angustifolium) , in 



northern Michigan, but farther south, 

 in Tuscola County, where it was also 

 very abundant, it did not yield a 

 pound of honey. The northern cli- 

 mate, and perhaps soil, were required 

 to stimulate nectar secretion. For 

 four consecutive years a good crop 

 has been obtained at Melford, north- 

 ern Saskatchewan, mainly from 

 willow-herb. This plant will yield 

 nectar with a cold wind blowing from 

 the north that would stop all storing 

 from basswood and white clover. 

 Willows, blueberries, Labrador tea 

 and asters all yield well in the North. 

 High altitude is evidently favorable 

 to an increase in nectar secretion. 

 But the number of species of flowers 

 in Arctic lands is much less than in 

 Alpine regions; for example, 60 ge- 

 nera of plants are known in the Alps 

 which do not occur north of the Arc- 

 tic Circle. 



The Effect of Intense Light 

 Soils and rainfall are undoubtedly 

 important factors in determining nec- 



tar secretion, but as they are common 

 to the lowlands as well as to Alpine 

 districts; and to the tropics as well 

 as to noi-thern regions, they will not 

 be considered in this paper. It may 

 be well, however, in passing, to say 

 that according to Prof. Fernald, the 

 distribution of Alpine plants on the 

 mountains of New England and east- 

 ern Canada is determined by the com- 

 position of the soils, according as 

 they are derived from rocks contain- 

 ing potash, lime, or magnesia. Two 

 factors of great importance in both 

 mountainous and northern areas are 

 light intensity and low temperature, 

 and to these we shall confine our at- 

 tention. The secretion of nectar is 

 closely related to the amount of light 

 the plant receives. The force or en- 

 orgy required for the manufacture 

 of food material is furnished by sun- 

 light. It is the power which drives 

 the plant, just as the electric current 

 is the power which drives the motor. 

 Deprive the plant of light, and the 

 sugar reserves will soon be consumed 

 and nectar secretion will cease. Ke- 

 noyer placed buckwheat flowers under 

 both light and dark jars, and after 

 two days the amount of sugar in the 

 nectar of the flowers under the dark 

 jar began to decrease. After four 

 dpys approximately only one-fourth 

 as much sugar was secreted per 

 flower. He obtained, also, the same 

 results by covering the leaves of the 

 plant with black paper. The flowers 

 of cucumber, snapdragon and sage 

 all secreted less sugar in darkness. If, 

 however, the flowers were placed in 

 the dark, and the leaves remained in 

 the light, the amount of sugar in the 

 nectar did not decrease. The secre- 

 tion of nectar is thus dependent on 

 the food reserves made by the leaves. 

 Darwin observed that the extra-floral 

 nectaries of the common vetch (Vicia 

 sativa) ceased to secrete nectar when 

 the sun was hidden by clouds, and the 

 hive-bees left the field, but as soon as 

 the sun broke out again they returned 

 to the feast. (Cross and Self-Fertili- 

 zation, etc., p. 403). 



The force of the sun's rays on the 

 top of Mt. Blanc (15,752 feet) is 2S 

 times greater than at the level of 

 Paris. At an altitude of 8,510 feet 

 the chemical activity of the sun's rays 

 is 11 per cent gi-eater than at sea 

 level. The greater intensity of the 

 light drives the machinery of the 

 plant more rapidly and more food is 

 made. The first stable, or the main 

 product foi-med is a sugar. If during 

 the daytime more sugar is formed 

 than can be used, it is stored in the 

 cells as starch. During the night the 

 starch is again converted into sugar. 

 There is thus available more material 

 for the production of flowers and 

 nectar than in the plains. That Al- 

 pine plants contain a larger amount 

 of sugar is shown by the abundance 

 ot red coloration or anthocyanin they 

 produce. As already has been shown, 

 this is formed only in cells which have 

 a cell-sap rich in sugar. Too intense 

 light is injurious, and the role of red 

 coloring may be to absorb a part of 

 the sun's rays. Light is also a direct 

 stimulus to the growth of flowers. In 

 the giant cactus, where the flowers 



