General Treatment For Peaches
( Originally Published Early 1900's )
Inspect for scale insects, the same as for apple, and spray with strong lime-sulphur wash the same as directed for apple trees.
If this spraying is made, it will also prevent the leaf-curl disease. If the lime-sulphur spraying is not required, a spraying must be made to prevent the leaf curl which is often especially serious on Elbertas. For this spraying, use Bordeaux mixture or the copper sulphate solution (2 pounds of copper sulphate dissolved in fifty gallons of water). It is very important that this spraying be made before the buds swell. If made after that time, it will not be successful in preventing the leaf curl.
If the fruit in your orchard is commonly affected with the rot and the scab (the small black specks usually on the upperside) and the curculio ("the insect that stings the fruit")—and most of the peach orchards in Michigan are affected with all of these—make sprayings as follows:
JUST AFTER THE BLOSSOMS DROP AND MOST OF THE "SHUCKS" HAVE FALLEN OFF, spray with poison, using 2 pounds of arsenate of lead in every 50 gallons of water.
(See under arsenate of lead page 164.)
Never use any arsenical other than arsenate of lead, on peach.
Two WEEKS AFTER THE PREVIOUS SPRAYING, another must be made.
This time use the self-boiled lime-sulphur and to every 50 gallons add 2 pounds of arsenate of lead. The dilute lime-sulphur has not been generally satisfactory on peaches. Even when very dilute some burning of the foilage has resulted.
ABOUT ONE MONTH BEFORE THE FRUIT RIPENS, spray again and the same as directed above.
In orchards where the curculio is not present or not serious, the spraying recommended "Just after the blossoms fall" can be omitted.
Self-boiled lime-sulphur settles rapidly, so keep well agitated and do not add the arsenate of lead until just before spraying. Use fine nozzles and give the trees a uniform coating of a mist-like spray.
PEACH TREE BORER. Dig out by hand early in spring or late in fall at points where gumming shows. Sterilize knife with carbolic acid to prevent spreading crown gall which may be present.
"PEACH YELLOWS" AND "LITTLE PEACH."
These two diseases are extremely infectious and very difficult to positively identify. Their causes are unknown and the only method of control is destruction of the tree—fruit, root and branch—as soon as discovered. It is especially important that diseased trees should not be allowed to blossom as it is believed the disease is spread by insects at that time. Both old and young trees of all varieties of peaches and probably all varieties of Japanese plums are susceptible to the two diseases. Both diseases may be present in a tree at the same time.
PEACH YELLOWS. The first symptoms in a young tree, previous to bearing, are indicated by the leaves of one or two limbs turning from a rich dark green to a "yellowish green or reddish rusty green" color; this is accompanied by a rolling of the leaves from their edges. These leaves ripen and fall earlier than normal leaves. The fruit buds are larger and more mature in appearance and in the spring will invariably bloom earlier than healthy buds. In some instances, the symptoms are not confined to one or two branches, but many of the leaves in the center of the tree turn yellowish or light green, roll slightly from their edges and droop considerably. These latter symptoms are often present in cases of "Little Peach."
Upon bearing trees, there may be any one or all of the following symptoms: the fruit may ripen prematurely—one to three weeks—upon one or two branches or over the entire tree. The fruit may have numerous red spots on the surface, the spots sometimes extending in red streaks partially or wholly through the flesh to the pit. Often the flesh, about the pit, is full of radiating streaks of red. The surface of the fruit may be smooth or considerably roughened and the flesh more or less stringy and very insipid. The leaves may be yellowish pale or reddish rusty green in color, usually rolling and drooping, In advanced stages, numerous finely branched shoots bearing many slender sickly leaves, appear on the trunk or main limbs and sometimes in the extremities of the branches. Finally the tree dies.
Winter injury to the bark of the trunk or main limbs, mechanical in-jury by mice, rabbits, peach borers, cultivators, etc., or a serious lack of moisture or nitrogen in the soil may discolor the foliage and cause premature ripening of fruit and should not be mistaken for "Yellows."
LITTLE PEACH. In "Little Peach," characteristic symptoms are : the leaves of a part or the whole of the tree have a bunched appearance, and are shorter, and broader than normal leaves. They are usually yellowish-green in color with the veins appearing dilated and darker than the intervening tissue. The fruit is usually under size and ripens from a week to two weeks late. The flesh is more or less stringy, watery and very insipid while the pit is usually very small. One or all symptoms may be present -and unless they can be positively attributed to some other cause, the tree should be condemned, pulled out and burned.