Page:Foods and their adulteration; origin, manufacture, and composition of food products; description of common adulterations, food standards, and national food laws and regulations (IA foodstheiradulte02wile).pdf/374

 come with frosts, makes the air heavier, so that it rolls down into the valleys, replacing the air on the hills with fresh portions unchilled and thus protecting the high ground from frost while the low ground is chilled below the freezing point. Everyone must have noticed, especially in the autumn at the time of the first frosts, that the vegetation in low lying land is usually killed before that on the adjacent hills. The peculiar susceptibility of the peach tree to the environment mentioned above has practically confined the culture of peaches to certain definite localities, as for instance to Michigan, Connecticut, Delaware, Maryland, Tennessee, and Georgia. The danger of late frosts of course does not attach to the peach tree grown in California and similarly situated localities. At the present time Georgia is probably the most important peach-growing state in the Union, both on account of the reasonable certainly of the crop and also because of the early date at which the peach can reach the markets of the large cities of the east and central portions of our country.

Many attempts have been made to protect the peach tree against the danger of premature blossoming and consequent exposure to the late frosts. In the cultivation of the trees it has been desirable to secure a variety which blooms as late in the spring as possible. The building of fires around a peach orchard in the spring when a frost is imminent has sometimes protected the orchard from disaster. This process is known as smudging. Another method of protecting the trees from the danger of late frosts is by whitewashing. The colors which absorb heat most readily are black and purple. White is one of the best protections by reason of its reflective power. A whitewashing of the branches of the trees and in fact of all the tree has been practiced with some success as retarding the early bloom of the buds. Elaborate studies of this method of treatment have been carried on by the Missouri station, and it has been developed that there is a considerable difference between the temperature of whitewashed and unwhitewashed peach twigs. The whitewash is therefore recommended as a means of retarding the development of the buds. The whitewashed trees bloom from a week to ten days later than those which are not thus treated. It is reasonably certain that by means of this kind or by cultivation a peach tree may be produced in any given locality which will put forth its buds from a week to ten days later than the normal period of blooming in that neighborhood. In regions where the winters are severe, the development of the tree in the early spring may also be prevented by placing straw round about it when the ground is frozen. The straw protects the frozen ground from rapid thawing and thus delays the development of the buds. The varieties of peach trees are legion, and it is useless to try to name them here. Some of the varieties most prized in Georgia are the Bishop, Champion, Crawford's Early, Chinese Free, Crimson Beauty, Crosby, etc.