By means of cutting, the size of the fruit can be effectively regulated. Winter or spring pruning reduces the number of flowers per tree, and therefore fruit, thanks to which each of them grows. The positive effect of cutting on the size of fruit is visible mainly in the years of abundant harvesting of trees. If the yield is sparse, even on uncut trees the fruit is large. Usually, as the trees age, the fruit becomes smaller and smaller. This phenomenon is commonly referred to as fruit reduction. Intensive pruning prevents fruit crumbling of apple varieties such as: Inflancka Olive, Melba, Wealthy, Spartan, Jonathan; pear of the varieties Faworytka and Konferencja; Hungarian Wangenheim plum variety.
The easiest way to improve the size of the fruit is by shortening and removing small berry branches. Good results are obtained when cutting old shoots, and leaving the younger, especially those, which are embedded in two-year increments (table). Cutting out old shoots and leaving young shoots effectively counteracts the small size of blackcurrant fruits. One of the purposes of cutting is to improve the color of the fruit. In older apple orchards it is impossible to get pretty pruning without pruning, ruddy apples.
Only young, apple trees that are several years old do not require pruning to improve the color of the apples, on the contrary, the prettiest apples grow on trees that are not cut. If the crowns of young trees are not cut, their twigs are then long, flabby, covered almost exclusively with shoots. Crowns are loose, making, that the sun's rays penetrate easily inside them. The small volume of the crowns at this age also facilitates the penetration of sunlight into all the twigs. Thanks to this, apples have a beautiful blush. Some ways of cutting, including, for example, shortening the shoots, may worsen the color of apples on young trees. Shortening the shoots results in a compact crown with stiff limbs and numerous intensively growing shoots, which prevent the penetration of sunlight into the crown. The apples are then less colored than on uncut trees.
Table. Effect of two ways of pruning old Wealthy apples on the amount of fruit above diameter 7 Cm (according to I. Łaźniewska and A.. Mica)
| Percentage of fruit with a diameter above 7 Cm | ||
| Year | moderate
x-raying heart |
x-raying and shortening
fine shoots |
| 1960 | 16 | 63 |
| 1961 | 64 | 81 |
| 1962 | 64 | 84 |
| 1963 | 30 | 50 |
| 1964 | 15 | 59 |
| 1965 | 16 | 16 |
Table. The relationship between the sun exposure of the crown and the color of apples of the Mclntosh variety in a row orchard (according to T. Jacyna)
| Crown height from the ground in cm | Percent | ||
| of the learner
lights solar |
jabtek
intensively red |
apples without blush | |
| 200-300 | 63,0 | 45,8 | 0,0 |
| 100-200 | 40,0 | 23,2 | 6,2 |
| 0-100 | 33,8 | 9,5 | 10,3 |
The observations presented above refer to young trees, aged from 1 into 6 lat. The situation is different in older trees.
If the apple tree is grafted on a vigorously growing rootstock or even on a semi-dwarf rootstock, then after six years it has a crown in diameter 3-4 meters, and also its height comes to 3 meters. Since then, the sun's rays can hardly penetrate inside. The lower and middle branches suffer from a lack of light. The lack of light prevents the formation of pretty apples (table).
In our climatic conditions, the twigs should be at least 50% sunlight, so that the blush can form on the apples. In parts of the crown, where, due to shading, the light reaches less than 50% of the light, the apples have only traces of a blush, and there, where the light reaches less than 30 ° / n, the fruit is not only green, but also uncultivated. Measurements of insolation in fruiting orchards show, that many trees do not have the conditions for the development of pretty apples.
The sunlight inside the crowns of old trees and the color of apples can be effectively improved by appropriate pruning. It involves loosening the crown, limiting its size and correcting its shape. Loosening should be cutting thick branches, and even branches. Cutting small shoots in old trees has a positive effect on the size of the fruit, but it does not improve the blush. The acceptable size of the crowns depends on the spacing of trees in the orchard. In old orchards, which are planted at 10X10 spacing, 8X8 or 8X6m crown diameter may vary from 6 into 8 m without fear of mutual shading of trees and the resulting negative effects. In intensive orchards, where the distances are from 6X4 to 4X3 m, you have to be very careful that the crowns are within the limits of 4 into 3 m in diameter.
Excessive height of trees can cause poor coloration of apples. In old orchards trees should not be taller than 3-4 m, and in intensive low-growing orchards - 2.5-3 m. In rowed orchards, the height of the walls should not be greater than 0,7 the width of the rows; the proportion between the height and the thickness of the lane walls should be kept. At the height 3 m, the thickness should not exceed 1,5 m.