Useful information

Oak: growing, propagation, pruning

Attitude to soil conditions

English oak, marsh and toothed oak are demanding on the mineral and organic richness of the soil. English oak grows best on normally moist, deep gray forest loams and on alluvial soils in the floodplains of large rivers; worse - on strongly podzol soils. With acidic humus, formed mainly with the participation of spruce, the oak dies, yielding to the domination of the latter.

English oak

Large anthered oak grows well on dry, fresh, fertile soils. The reaction of the medium varies from slightly acidic to alkaline. Poorly tolerates even the slightest salinity and shading.

Marsh oak prefers moist soils, as it naturally grows on deep, moist soils of river banks and swamps.

The oak is red and is characterized by undemanding soil fertility. The tree can withstand an acidic environment and should not be planted on calcareous or highly moist soils.

Mongolian oak reaches its best development on fresh, deep and fertile soils. But it can grow on soils of a wide range of fertility, including poor stony ones. On swampy and constantly waterlogged soils with high acidity, as well as in systematically flooded floodplains of rivers, oak does not grow.

Reproduction and cultivation

Reproduction of oak is possible by rooting of green cuttings, the result of which depends on the age of the mother plants. Cuttings from adult plants practically do not take root, from young ones quite successfully. For example, cuttings taken from annual plants rooted by 70-90%, while from biennial plants - by 30-70%.

Rooting is influenced by the timing of cuttings. Cuttings of annual seedlings rooted well from the first decade of June to the third decade of July inclusive (rooting 60-95%). For 15-year-old plants, the best period for propagation by cuttings was May; when cuttings were cut in the second half of July, the cuttings did not take root. Heteroauxin at a concentration of 100 mg / l has proven itself as a rooting stimulator.

Mongolian and English oak root (12%) when treated with 0.01% and 0.05% indole butyric acid (IMA) solution. In the Gartvis oak, 22% rooted, in the red oak —30% of summer cuttings treated with a 0.05% IMC solution.

Red oak, acorn

Oaks reproduce well by planting freshly harvested acorns. September and October are considered the beginning of collection, and for some species even November. Acorns collected and sown in August have a low germination rate.

Acorns are sown immediately after harvesting in the fall, avoiding drying out. Within 10 days, germination decreases to 50%, and after 20 days it is completely lost. The seeding depth of large acorns is 8 cm, of small ones - 5 cm. When sowing in September, if the autumn is dry, the acorns should be watered. To protect against damage by rodents, the ridges are covered with spruce branches.

If it is not possible to sow acorns in the fall, then they must be dried to a moisture content of 60%. A well-dried acorn should be as dry as possible, but the cupule should not come off. If this happens, the acorns are dry. It is better to store them until spring in a basement with moderate ventilation. For storage in the basement, acorns are placed in a box in layers: the first is 10 cm thick sand, the second is 2 cm acorns, the third is 2 cm sand. The second and third layers can be alternated 5 times. The moisture content of the sand should be about 60%, and the temperature should be 2-5 ° C.

A small batch of acorns can be stored in the refrigerator in a bag with small breathing holes. The optimum storage temperature is 2-3 ° C. Storing them in an airtight or tightly closed container can lead to the death of acorns. Periodically, once every 10 days, it is advisable to take them out and examine them. If mold appears, then the acorns must be washed, dried and put back in the refrigerator.

For winter storage, you can also bury acorns in the soil in the fall to a depth of at least 20 cm, covering the top with a sheet of waterproof material, leaving a layer of air between this sheet and the acorns and providing protection from mice. No special preparation of stored acorns is required prior to sowing in the spring.

Scalloped oak

After good storage in winter with spring sowing, mass shoots appear in about a month. During germination, the acorn shell cracks at the top, the cotyledons remain underground, and a white root appears outward. In two weeks, it reaches a length of about 10 cm, only after that the stem is thrown out. In the first year, oak seedlings reach 10-15 cm in height. With a long summer, they often give a second growth in the second half of it, and then they reach 20-30 cm in height. In the first year, oak seedlings form a taproot that goes deep into the soil up to 40-60 cm. In the future, it is very difficult to transplant seedlings without damaging the root. Therefore, to give the oak a fibrous root system in seedlings when they reach a height of 8-10 cm, the root is cut with a shovel. In the future, oak is grown in the first, second and often in the third school.

In the I nursery school, a tree trunk is first formed within 4-5 years. At this time, conditions are created for the growth of the central conductor (leader), directing the main nutrients into it with the help of various scraps. The emerging shoots, competing with the leader in terms of growth force in length or thickness, are cut into a ring. For the growth of the leader in thickness along the diameter, thickening shoots are used. They develop on the stem along the entire length of the planned stem. Thickening shoots are obtained by pinching in mid-May of the lateral branches formed on the trunk when their length reaches 20 cm. Thickening shoots 10 cm long are left. Thickening shoots are kept on the trunk until it reaches a standard size. After that, the shoots are cut out. In oak, the trunk thickens quickly, especially in the lower part, therefore, a small number of thickening shoots are left near the tree, mainly in the upper part of the trunk. First, the thickening shoots are removed from the lower third of the stem, the next year - from the middle part of the stem, and the rest - in the third year. In the second school, the crown is formed. To lay the crown, measure the height of the trunk, count 5-7 buds, cut the leader shoot above the counted bud. The next year, before the start of the growing season, the growths that have developed from the left buds are also cut off by 5-7 buds, outer with respect to the axis of the trunk. The growth located above the trunk is cut one internode higher than the one below. Such pruning helps to obtain an evenly developed crown. From the buds remaining on the skeletal branches of the first order, branches of the second order develop. The oak is grown in nurseries until the age of 20 and is planted with a tree about 8 m tall with a well-formed crown.

Pruning

The oak has monopodial branching. This means that the main stem grows at its top until the end of the plant's life, possessing unlimited apical growth, which dominates the growth of lateral shoots.

All types of oak trees form a powerful straight trunk (sometimes several), which continues to grow throughout the life of the tree. Timely pruning of oak branches, which is carried out every 2-3 years, allows to limit the growth of the crown. The formation of the above-ground part of the tree provides for various methods of pruning oak branches.

Removal of the apical bud slows down the height of the trunk. Pinching of the shoot (removal of the top), shortening of the shoot or branch, cutting of the branch or shoot is also carried out. Cutting only the growth over the entire crown promotes branching and excessive thickening. When pruning shoots, the length of the cut off part depends on their growth rate. When you remove part of the growth and whole branches, the crown turns out to be openwork and even lets a certain amount of sunlight pass through.

The optimal period when you can prune the oak is the end of winter and early spring. Removing branches in winter is possible if the outside temperature does not drop below -5 ° C. At a lower air temperature, freezing of the areas of bark and wood adjacent to the cut is possible. Pruning a tree in summer must be done with care; you cannot cut many branches at this time of the year.

When carrying out sanitary pruning, first of all, diseased, drying out, mechanically damaged and growing inside the crown of the tree branches are cut out (from mid-February to mid-April and in the second half of summer, when the growth of shoots is completely completed).

Photo by the author