Korean or Manchurian cedar grows in Primorye, Amur Region and Khabarovsk Territory. Outside of Russia, it is distributed in northeastern China, in central Japan and Korea. Due to valuable timber, the culture is almost completely exterminated in China, and for the Amur region it is protected and listed in the Red Book.
How to tell a cedar pine from a cedar
In fact, Korean cedar is not a cedar at all. It doesn't even belong to the Cedrus genus. Its full botanical name is Korean Cedar Pine (Pinus koraiensis), and it belongs to the numerous and diverse genus Pine. Such confusion in the Russian language has arisen a long time ago, and it seems that no one is particularly confused.
Nuts of the Korean cedar (which, by the way, are not nuts in the botanical sense), unlike the seeds of the present, are edible and are a valuable food and medicinal product. Although Cedrus and Pinus belong to the same family - Pine, they have a lot of differences:
- Korean cedar grows in temperate and cold climates, but the real one is very thermophilic;
- in pine trees, the roots go deep into the ground, while cedars spread them in breadth and can be uprooted by a strong wind;
- the needles of the Korean cedar are long, can reach 20 cm, while the real needles grow up to a maximum of 5 cm;
- the needles of a real cedar are collected in bunches of 40 pieces, in the Korean - 5;
- the buds of these crops are very different from each other;
- the seeds of the cedar pine are edible, covered with a hard skin, which is why they really look like nuts, while in the cedar they are much smaller, with a thin shell, and, moreover, have a large wing.
There are other differences, but in order to learn about the culture, it is enough to look at the needles or cones.
There are four types of cedar pines:
- Dwarf plant.
All of them have edible nuts and are only distantly related to real cedar.
True cedar (Cedrus), in turn, includes three types:
Description of Korean cedar
Korean cedar pine is an evergreen coniferous tree up to 40 m high with a multi-peaked, low-hanging crown in the form of a wide cone. The ends of the open branches are raised upward, the bark is thick, smooth, dark gray or gray-brown. Young shoots are brownish with a reddish edge.
The average length of gray-green rigid needles with blunt ends is 7-15 cm, the maximum is 20 cm. Triangular needles are collected together in 5 pieces and live for 2-4 years.
In May, yellow or pale pink male microstrobilis located inside the crown bloom on Korean cedar. Female cones form at the tops of large branches. During flowering, they are beige or pale pink, after fertilization they turn green, at the end of summer they turn light brown and remain so until the next spring. At the beginning of the second vegetative season, the cones begin to grow actively and turn green again. After ripening, they turn beige or light brown.
The size of ripe cones of Korean cedar pine is up to 18 cm long (individual up to 23 cm), diameter is about 6-9 cm. The shape resembles an elongated egg with scales bent outward. The seeds, incorrectly called pine nuts, reach 1.8 cm in length with a maximum diameter of 1 cm.
Cones ripen in autumn, one and a half years after pollination. Some of them fall off, some remain hanging until spring. Fruiting begins at 25-30 years, the lifespan of the Korean cedar is up to 600 years.
Differences between Siberian and Korean cedar pine cones
Various sources devote regrettably little attention to the description of the cones of various cedar pines. In Russia, three types are widespread - Korean, Siberian and Stlanikovaya. And although they are very different from each other, amateurs can easily recognize only the last species - dwarf cedar. It is a small tree or shrub that bends branches to the ground and forms impenetrable thickets.
The other two pines are not only confused, but are often included in articles about Korean cedar, photography and description of Siberian. You need to distinguish them:
- Mature Korean pine cones are twice as large as those of Siberian pine.
- Seeds of Korean cedar reach a length of 18 mm, Siberian cedar - a maximum of 12 mm.
- During flowering, the cones of Korean cedar are beige, during ripening they are green. The Siberian has crimson and purple, respectively.
- Cones of Korean cedar ripen in October, Siberian - by August.
The difference between cones and seeds is easy to see in the photo of Korean cedar, Siberian and elfin.
Varieties of Korean cedar pine
Cedar pines look attractive, but they are too large for small areas. Therefore, selection is aimed not so much at breeding varieties with an original crown shape or bright needles, as at reducing the size of the tree.
Korean cedar Sulange
This is not a variety, but a variety of Korean cedar pine. A tree up to 40 m tall with a long (up to 20 cm) gray-green needles begins to bear fruit in the 15-20th year of life. The crown is dense, openwork. Soulange tolerates air pollution much better than the main species, which allows it to be grown in city parks. Fruiting is of great economic importance, starting 10 years earlier than that of ordinary Korean cedar.
Korean pine silver
Silveray is an ornamental variety with a pyramidal crown and long, slightly curved needles that have a silvery blue tint. By the age of ten, the tree reaches a growth of 250 cm, with a diameter of 120 cm, annually increasing by 25 cm.
The variety is distinguished by high frost resistance, picky about soil fertility and does not tolerate stagnant water at the roots.
Korean cedar Morris Blue
This variety was bred in Pennsylvania and is highly frost-resistant. Forms a dense conical crown with silvery-blue needles, collected in 5 pieces. During the season, the growth is 15-20 cm. An adult Korean cedar, Maurice Blue, grows up to 3.5 m with a crown width of 1.8 m.
The bark is gray and looks especially attractive in winter. It tolerates urban conditions poorly, requires a sunny location, does not tolerate stagnant water in the root area, but tolerates drought well. Lives up to 120 years.
Korean cedars of Russian selection
In the post-Soviet space, the Tomsk enterprise Siberian Academy of Trees and Shrubs has been engaged in the selection of Korean cedars for more than 20 years. They created the Blue Amur variety, which has blue needles and is 4 m tall.
In the Far East, breeder Alexander Simonenko is engaged in Korean cedar pine. In the Tomsk nursery, two dwarf early-growing fruitful varieties are currently being tested: Patriarch and Svyatoslav.
Unfortunately, it is almost impossible to buy Russian cultivars - they are bought up on the spot, preventing them from even reaching the age of two.
Growing Korean cedar from seeds
Before planting Korean cedar seeds, it should be noted that varieties reproduce only by grafting. Species tall plants, unsuitable for decorating a small area, will grow from their nuts. For planting Korean cedars in order to obtain a harvest, the seeds of positive, that is, the best, trees are better suited. To do this, choose the largest cones with large scales.
Sowing seeds in autumn
From late September to early November, Korean cedar pine seeds are sown without stratification. Germination rate will be 91%, while in spring planting it will be 76%. Previously, the seeds are soaked for 3-4 days in a 0.5% solution of potassium permanganate and sown on ridges in rows 10-15 cm apart from each other.
They are sealed to a depth of 3-4 cm and first mulched, and then covered with spruce branches. This will not only protect the soaked seeds from freezing in winter, but also save them from mice and birds. Sowing rate - 200 pieces per running meter - cedar pine seedlings are not afraid of thickening.
When sowing seeds of Korean cedar pine in the spring, it is imperative to carry out stratification. Ideally, this takes 80-90 days. The seeds are soaked for 3-4 days in a solution of citric acid and heteroauxin, placed in a box with wet sawdust or sand and left outside under the snow.
But what if the planting material was purchased in the spring? The seeds are soaked in warm water for 6-8 days, changing it every 2 days. Then it is stirred with washed sand and left at room temperature. Korean cedar seeds will hatch in about a month or more.
They are immediately placed in a refrigerator or transferred to a room with a temperature close to 0 ° C, where they are stored until planting in the ground.
Seeds that have been treated with low temperatures are sown on the ridges in late April or early May, just like in autumn.
Further care of seedlings
In the spring, in order to prevent the birds from pecking up the seedlings, the ridges are covered with a transparent film, they are removed only after the shell has fallen off. Cedar pines are picked very early, in a cotyledonous state, and even better before they open. Then the survival rate will be about 95%.
Important! In order to pick cedars at the “key” stage, you need a certain skill.
Before planting in a permanent place, seedlings are transplanted into schools several times. It is best to carry out the operation in the spring, but if necessary, you can also in the fall. First, three-year-old cedar pines are planted at a distance of 30-35 cm in rows spaced 1 m apart from each other.After 3-5 years, they are transferred to a new school, they are arranged according to the 1x1 m scheme.
All this time, cedars are moderately watered, fed and protected from the midday sun. Coniferous litter is added to the soil of the schools - this makes the seedlings grow faster.
Outdoor planting and care
When planting Korean cedar, there should be no special difficulties. It is important to choose a high-quality seedling and a place for it - adult pines do not tolerate movement well. To get a good harvest, at least two trees must grow nearby.
Important! A single Korean cedar will produce few cones, and they will be small and misshapen, often with empty nuts.
Selection and preparation of the landing site
Korean cedar prefers acidic, moderately fertile soils, rich in humus and permeable to water and air. They thrive on rocky soils, are resistant to high winds, and tolerate shading at a young age. Over time, pines become very light-requiring.
Korean cedars can grow in areas with a groundwater table of more than 1.5 m - their root system is powerful, deeply embedded in the ground, and does not tolerate being locked. When preparing a site, the roots of weeds are removed from the soil, stones, if any, are left.
The planting pit should be spacious enough - with a depth and diameter of about 1-1.5 m. To prepare the nutrient mixture, the top layer of soil is mixed with 3-5 buckets of leaf humus, sour peat and at least 20 liters of coniferous litter.
All these additives acidify the soil and make it loose, permeable to air and water. With a close standing of groundwater, the pit is made deeper and drainage is poured onto the bottom - gravel, broken red brick.
Preparation of planting material
It is best to immediately plant large-sized Korean cedar pine - ten-year-old trees above 80 cm.But they are quite expensive, and at least two copies are needed to get a harvest. Therefore, many gardeners are forced to buy small seedlings. Their only advantage over large-sized ones (except for the price) is the ease of planting.
Container plants are watered the day before being moved outdoors. Dug out seedlings should be bought with a large earthy clod, protected with damp burlap or foil. It is recommended to plant them as soon as possible.
Important! Pine trees with an open root system cannot be purchased.
Korean cedar pines, planted for decorative purposes, can be placed at a distance of 4 m from each other. To ensure good fruiting, the minimum gap between trees is 6-8 m.If space permits, it is better to increase the distance to 10-12 m.
Before planting Korean cedar pine, the previously dug planting hole is completely filled with water, after filling it with a fertile mixture by 1/3. When moisture is absorbed:
- Fertile soil is poured to the bottom so that the root collar is flush with the edge of the pit.
- A Korean cedar is placed in the center.
- The planting hole is gradually filled with a fertile mixture and rammed.
- Check and, if necessary, correct the position of the root collar.
- Korean cedar is watered abundantly.
- The trunk circle is mulched with sour peat or coniferous litter.
Watering and feeding
They attach great importance to feeding and watering cedar pine in the first 10 years of its life. Then fertilizers are replaced by mulching, and watering is carried out several times over the summer, if the weather is dry.
Care for a young plant must be careful. For top dressing, it is best to use special fertilizers for conifers. They are released for each season separately, observing the balance of substances necessary for the tree, and are used 3 times during the growing season. If it is not possible to use special feeding, they give the usual:
- in spring, after the snow melts - with a predominance of nitrogen;
- at the beginning of summer - a complete mineral complex;
- in the middle or end of August - phosphorus-potassium (no nitrogen).
Throughout the growing season, Korean cedar, like other conifers, is useful to give foliar feeding. For this, it is better to use chelate complexes and magnesium sulfate.
Watering of young cedar pines is carried out as the soil dries out. It is better to skip watering than to allow water to stagnate in the root area.
Pruning and shaping Korean cedar
Pruning is not included in the Korean cedar care complex. In early spring or autumn, only dry branches are removed. Formative pruning is not carried out at all.
Preparing for winter
For the winter, Korean cedars are sheltered only in the first year after planting. It is a hardy crop that tolerates temperature drop well. The seedlings are wrapped in white agrofibre or spandbond and secured with twine.
Korean cedar yield
Korean cedar pines grown from seeds begin to bear fruit 25-30 years after the emergence of seedlings, grafted - sometimes after several years. Under natural conditions, trees often give a crop only after 60 years.
Cones ripen at the end of October, the next year after pollination. Each contains from 100 to 160 seeds weighing 0.5-0.6 g, and the kernel is 35-40% of the weight of the "nut".
Korean cedar pine cones grow in groups, and only on the tops of trees, only a few can be located on the branches adjacent to the crown. On young specimens, the seeds are usually larger than on older ones.
Under favorable conditions, the Korean cedar enters the maximum fruiting by the age of 100-170. It lasts up to 350-450 years. Good harvests are harvested every 3-4 years, but the complete absence of fruits is almost never observed. In a good year, one adult tree gives up to 500 cones, that is, 25-40 kg of "nuts". Under natural conditions, the yield can range from 150 to 450 kg / ha.
The productivity of a cedar tree depends on the age of the trees and their location. The largest harvest is given by Korean pines, adjacent to hazel, maple, oak and linden, growing on the southern side of the lower part of the mountains.
Diseases and pests
Korean cedar, like all pines, is often affected by pests and sick. The most dangerous age for species plants is 30-40 years. Varieties require constant attention. Artificial plantations of cedar pine suffer from gas pollution and chlorosis.
The most dangerous disease is resin cancer, which is also called seryanka or blister rust.
Of the pests of Korean cedar pine, the following should be distinguished:
- pine shield;
- pine moth;
- hermes - pine aphid;
- pine scoop;
- sprouting pine silkworm.
When pests attack, trees are treated with insecticides, diseases are treated with fungicides. On large plantations, the processing of pine cedars is difficult.
Reviews of Korean cedar
Elena Vsevolodovna Kruchinina, 40 years old, Pavlov Posad
When my husband and I bought Korean cedars, we were very worried about whether they would grow with us. We took two-year-olds in containers, very small. The trees took root badly, then it turned out that it was better to take large ones, but they cost much more. I had to water with Megafol and constantly spray with epin. They have taken root, but they grow slowly - about 10 cm per year. Already 5 years have passed, and they are very small. True, they are no longer capricious. They overwinter quite calmly, we do not cover anything, only we mulch the trunk circle with fallen needles from the neighboring forest. It seems that they liked it with us, and no problems are foreseen.
Sergey Vladimirovich Kuznetsov, 63 years old, Gatchina
I have a large plot outside the city. I planted a dozen Korean cedars, but not for the purpose of obtaining nuts, but because, unlike ordinary pines, their lower part is not exposed. I wanted the site to look beautiful for a long time and immediately. Therefore, I took large-sized ones. The choice fell on the Korean cedar because it has the largest cones, I thought they would litter the area. 20 years have passed, the cedars have taken root well, they require little care, they winter without problems, they give a lot of cones, however, not every year. So now I am not only with beauty, but also with the harvest.
Korean cedar is a beautiful large tree that grows slowly, has a long life and gives tasty healthy seeds. In park culture, species are used; owners of small plots can plant varieties. For a tree, you need to choose the right place and surround it with minimal care in the first 10 years of life, then it practically does not cause trouble for the owners.