. American bee journal. Bee culture; Bees. 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 i
. American bee journal. Bee culture; Bees. 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
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Keywords: ., bo, bookcentury1800, bookdecade1860, booksubjectbees, bookyear1861
