Leaf fall - seasonal update: oak, mountain ash, poplar, apple tree. When does leaf fall end for birch, linden, maple When does leaf fall end for other trees

Birches are deciduous plants, every year they shed their leaves in order to acquire fresh green “clothes” again in the spring. When does birch leaf fall end? This is often asked by students. Our material will help you understand this and learn a lot interesting facts about this seasonal event.

What is leaf fall?

The term, so familiar to everyone, refers to the biological process during which the leaves of trees, which have lost chlorophyll, are separated from the stems and fall to the ground. This process is characterized by the following features:

• In autumn, the trees take on a variety of colorful colors, from yellow and orange to crimson and crimson red. This happens because before the leaves fall, chlorophyll, the pigment that gives them green color.
• The leaves acquire the ability to easily separate from the branch even with a slight gust of wind due to the formation of a special separating layer that breaks the connection between the leaf and its stem.
• Due to this seasonal phenomenon, the trees are freed from those harmful substances that have accumulated in the leaves during the season of active growth.
• With the help of leaf fall, plants are protected from excessive loss of moisture, which is extracted from the soil in harsh weather. winter time becomes very difficult.

We have considered the main signs of the most important seasonal change in the life of trees. Now let's get acquainted with when the leaf fall near the birch ends, and also when it begins.

Birch

Early autumn is characterized by still warm weather conditions, the thermometer often has a positive value, however, precipitation in the form of drizzle and hoarfrost can fall. The trees begin to turn yellow, playing in the rays of the already dim sun with stunningly beautiful colors. In the first week of September, the thin-stemmed tree begins to lose its foliage.

The average duration of leaf fall depends on weather conditions and can be from 15 to 20 days. The answer to the question of in what month the birch leaf fall ended can be given as follows: September ( last days this month) or October (its first half).

Process Features

Birch is one of the first trees to lose foliage, along with aspens, maples, lindens. Considering when the birch leaf fall ends, it should be noted that by the end of October these beautiful trees standing completely naked. The fall of the leaves of the plant begins on September 15, completion - by about October 5, but it is impossible to name a more exact date - it all depends on natural conditions each specific year. The main activity of the process begins after the first frosts, which, as a rule, fall on the last days of September (from about the 28th).

Folk omens

We examined when the leaf fall near the birch ends. Why do people need this knowledge? First of all, observing nature is interesting in itself. However, there are also several folk signs, which were used by our distant ancestors to predict the weather. Some of them are interesting in their own way:

• If the leaves fall from birch and oak simultaneously and evenly, it is worth waiting for a mild winter.
• harsh winter expected if oaks and birches become bare in different time.
• The leaves turned yellow, but did not fall off by the time - there will be frosts.
• The leaves on the white-stemmed tree did not fall in the first week of October - the snow will fall late this year.
• The leaf fall is “according to the scenario”, the tree sheds its foliage in time - we should expect a long thaw at the end of January.

Unfortunately, it is impossible to accurately answer the question of what date the leaf fall of birches ends, however, everyone can determine the approximate time frame: the process of leaf fall of a traditional Russian tree ends by the end of September or the beginning (less often - the second half) October.

This happens because, in addition to chlorophyll, there are other coloring substances in the leaves. It is especially abundant at the end of September and the first decade of October. In what period does the leaf fall of linden and birch begin and end?

With the onset of September, the trees gradually begin to change the summer emerald green color of the leaves to autumn yellow. By mid-September, birch leaves become ocher-gold and gradually begin to fall off.

For many trees, leaf fall is uneven, that is, it happens at different times. For example, after the first severe frost, leaf fall begins in linden and maples. By this time, the birch had already dropped most of the leaves.

It is difficult to unequivocally answer the question when the time of leaf fall ends. It is noticed that first poplar leaves are lost, then oaks and mountain ash. Dropping leaves from trees serves another purpose - the crown under the snow cover has a significant weight. The branches of trees, especially young ones, are not able to withstand such a load. Thanks to the process of photosynthesis, a large amount of harmful substances accumulate in the leaves by the beginning of autumn, which, with the onset of leaf fall, are removed along with fallen leaves.

Poplar During the period of leaf fall, adult poplar trees lose a third of their leaves in the period from September 15 to 20, in the first ten days of October, up to 10% of foliage remains in the poplar crown. Young poplars remain green longer than old trees, they turn yellow later and shed their leaves. Oak Oak leaves fall off in the first half of September, after about 30 days the trees completely lose their leaves.

Oak leaves immediately acquire a brown color, along with the leaves, ripe acorns fall from the tree. Rowan Autumn rowan seems to be painted with watercolors, its leaves do not turn yellow, but acquire pink coloration, the process of leaf fall begins around the beginning of October, and ends by November 1.

The fall of apple trees begins in the third decade of September and ends in the second half of October. Birch is a genus of deciduous shrubs and trees of the Birch family, which is distributed in almost the entire Northern Hemisphere. Birch is better known to us as a tree up to 45 meters high and with a girth of up to one and a half meters.

Yes, many of us dislike this time of year because of the constant rain and sleet, but without a doubt - early autumn very beautiful due to the changing color of the trees. For example, the same birch begins to change color around the 20th of August, although this, of course, also depends on the weather.

However, we repeat, it all depends on the weather in the region. If, for some reason, the weather has changed so much that the temperature drops from the usual +20°C to -5°C, then the leaf fall begins almost immediately with the first frost. The remains of the leaves, which can remain on the trees even in the case of active leaf fall, usually fall off after the third or fourth hard frost, and this applies to most trees.

Trees at the time of leaf fall

Reprinting of materials and their use in any form, including in electronic media, is possible only with a back active link to our site, which is not closed from indexing by search engines. handsome autumn forest when the fall begins. Forest glades dressed in yellow colors, a river valleys- in wine red and pink shades. In the second half of September, poplars are also multi-colored: some of them become lemon yellow, others almost orange, some golden yellow.

By the end of September, even this strong, mighty tree obeys the general laws of nature - it becomes straw-yellow. True, poplar and birch shed their leaves long before the general cold snap. In aspen, leaf fall ends 5-6 days earlier than in birch. By September 15-20, old poplars are bare by a third, and by October 10, no more than 10-12% of the leaves remain on the trees.

Features of leaf fall

The leaf fall of different trees is uneven and sometimes lasts for several weeks. Here are a few aspens, elms, elms, ash and apple trees standing almost naked, and not so far from them - trees of the same age, but with rustling foliage still almost completely preserved.

September - the first signs of the coming autumn are already visible on the trees. The birch is the first to play in the autumn rays of the still warm sun with the yellowness of the leaves, the crowns of the trees are covered with the first noticeable gilding. On August 23, 2016, along the roads in the suburbs of St. Petersburg (specifically Oselki, Leskolovo, Ekaterinovka), I observed crimson maples in their entirety and in separate branches.

Apparently it's a combination of moisture, heat and daylight hours. The summer was very rainy and moderately warm. And by the middle of the month, the forests are bare. In the Leningrad, Pskov and Novgorod regions, the end of leaf fall of birch and mountain ash is observed on average on October 14. In October, the little warblers, warblers, shrikes, and corncrakes fly away from us. In the first days of the month, there is (on average) a mass passage of geese in the Tver and Yaroslavl regions.

Their mass departure is observed in the Tver region on October 18, in the Moscow region - on October 6, in the Vladimir and Oryol regions - on October 8-9. The departure of starlings ends, as a rule, in the last decade of the month. The mallard flies behind the starlings. Some birds stay with us for the winter. And not only rooks winter in our cities.

The beginning of autumn - 29 days: from August 26 to September 24. Leaf fall at the birch begins around the first half of September and lasts for another 20 days, that is, this tree completely falls off by the end of September-mid-October.

A common tree in Russia, it has beautiful curly leaves with five sharp ends. The tree is very picturesque, especially noticeable in autumn, when the foliage takes on many shades of golden and red. And when the leaves fall, it is so nice to collect bright autumn bouquets from them.

In this article we will talk about the maple itself, about its features and types, as well as about when the maple leaf fall begins and ends, on what conditions the timing of this depends. natural phenomenon.

Why does a tree need leaf fall?

With the onset of the first signs of a cold snap in the tree trunk, the delivery of nutrients through the stem vessels slows down. It is in the root system that these substances are stored, and each leaf of a tree is a small laboratory for their production. From the incoming water with minerals dissolved in it, under the action of photosynthesis (that is, with the help of sunlight), the cells of a green leaf produce everything necessary for the life of a plant.

But now the sun and heat are getting smaller, the days are getting shorter, and the tree, as if realizing that winter will come soon with cloudy days and frosts, it is accepted to store the necessary substances at the root. During the preparation of the plant for winter dormancy, the leaves change color and fly around. This is how the fall begins.

special maple

Maple - in many ways unique tree. It is frost-resistant, one of the first to “wake up” in spring, and easily tolerate drought in summer. It is avoided by insect pests common to other trees, rodents and moose do not like young foliage and bark because of the bitter taste. That is why maple leaves often remain intact until autumn, without flaws and wormholes.

Mushroom lovers know that it is useless to look for them under this tree.

Bees actively fly to the flowering maple. They like to feast on winged maple seeds and squirrel flowers, field mice and some birds such as bullfinches and nuthatches. The seeds, by the way, only ripen late autumn when the maple ends falling leaves, and fall to the snow-covered ground.

Maples look great in parks and gardens - they have a light, thanks to long petioles, fluttering crown with curly leaves, beautiful wood color and bright autumn foliage colors.

From some types of maple (sugar, black, red, holly), when the trunk is cut in the spring, maple sap is obtained, which is then boiled down to syrup. Maple syrup has a special taste. It is often used as an additive to confectionery.

Maple species

Maple is widely distributed throughout the earth, mainly in the Northern Hemisphere. There are 20 species of maples growing in Russia. The most famous of them are: holly (or plane-shaped), Tatar, white, field.

Holly has five leaf lobes. From three to five ends of a field maple leaf.

On the Far East there is a Japanese maple. He has seven-, nine-pointed leaves and a bizarre bend in the trunk. This species is listed in the Red Book.

Individual specimens of maples, for example, white maple, can reach a height of 40 meters, while the usual height of Norway maple is 28-30 meters. There are shrubby maples, in which individual trunks can be ten meters high.

Maple leaf fall dates

Maple, as mentioned above, easily tolerates cold. Active leaf drop begins after the first frost, and this is the average on September 27th. By this time everything Maple leaves are already painted in autumn colors.

In October, it is time for strong leaf fall for most trees. It is impossible to say exactly when the leaf fall of the maple ends, but usually by the middle or end of the month the tree loses its foliage.

It is clear that the average date is inaccurate. Because if you live in southern regions, the end of the leaf fall of the maple may shift for a month or more - and the leaf fall will end only by mid-November. But if in the north - on the contrary, the first frosts can descend in these parts even at the end of August.

Another time when the leaf fall of the maple ends depends on the particular winter. It happens that autumn is protracted, not cold, frosts come later than usual, and the leaf fall comes and ends later.

Much depends on the conditions in which the tree grows. For example, in open and flooded or wetlands, a tree loses leaves faster than in a dense forest.

It is interesting that trees growing near street lamps shed their leaves later - after all, the daylight hours for them are increased.

Also, the period of leaf shedding depends on the age of the plant. How younger tree, the later it loses leaves.

In order to know exactly what kind of “routine” plants and animals live in your area, you need to observe changes in wildlife. It's educational and interesting.

Mountain ash, viburnum, thickets of hawthorn blaze with flames. And some apple trees stand like bonfires: these are the latest, the last apples in the garden - Welsey, Pepin saffron, Lobo, Spartan, Rossoshansky striped apples filled with raspberry-red fire. The trees were bent under the weight of the harvest. The weather is still warm. She had kept the leaves active for the last few weeks before a bitter October wind and cold rain they cover the damp earth.

For all the time of their short life, not one of them slept even an hour, assimilating the sun's rays, carbon dioxide, mineral salts, producing nutrients and sending them to the still ripening shoots, fruits, spears, twigs, flower buds, roots - to where they are still required to complete growth, to be deposited in reserve.
The above-ground part of the tree at this time is more and more deeply covered by a state of rest. By introducing humus, compost, manure, even just by mulching the soil, you can significantly extend their active work, since these measures help to keep the heat in the root-inhabited soil layer longer and thereby increase the accumulation of nutrients.

Little of, fruit trees and shrubs can be specially prepared for the winter. In order for them to meet it prepared, it is important to cultivate the soil in the aisles and on the near-stem circles (strips) in a timely manner, apply fertilizers, carry out water-charging irrigation, taking into account the future, and the fact that autumn drought is not uncommon even in the forest belt.

A significant role is played by the work of those leaves that remain on trees and bushes until late autumn and provide all living tissues both in the aerial part and in the roots with plastic substances that are deposited in reserve and increase the resistance of trees and shrubs to all sorts of adversities. And it’s very good when they stay longer on the tree, although it happens that this serves as an indicator of the incomplete ripening of shoots and buds: the timing of leaf fall does not coincide over the years and depends more on the course of the weather than on our efforts, but still high agricultural technology contributes to more long activity of leaves.

For a long time and in different areas of the country, it has been noticed that in early varieties, preparation for winter dormancy is completed faster, they also move on to shedding leaves earlier. Care also affects them.
The leaf, ready to leave the branch, acquires a color characteristic of the variety, a separating layer appears at the base of its petiole. This place will then quickly grow impenetrable cork layer. Lentils on shoots also hide behind similar "shutters".

The buds, laid in the axils of the leaves on the shoots in the middle of summer, stop growing long before the leaf fall. Inhibitors released by the apical bud of the shoot and leaves slow it down more and more and, finally, stop it completely. All varieties horticultural crops differ significantly in the need for cold in order to resume vegetation. Usually it is expressed as the sum of hours of autumn and winter temperatures not exceeding 7 degrees.

However, complete, or, as they say, absolute, organic peace still cannot be considered. Some researchers have observed changes in growth points and generative buds even in the middle of the dormant period. What are the most characteristic signs for this? In the cells of the growth cones and adjacent tissues, the viscosity of the protoplasm increases greatly, it often moves away from the cell walls, and the connection between individual protoplasts becomes very limited. Lipoids accumulate on their surface, sharply weakening the ability of the cytoplasm to swell, and the nucleus loses its usual round shape and is not clearly distinguished from the protoplasm. By the end of the dormant period, they dissolve, and the connection between the protoplasts is restored, their vital functions and capabilities expand. And already in late December - early January, the buds acquire the ability to awaken, grow, bloom leaves and flowers. And by transferring the branch of the apple tree into the room, putting it in a vase of water, you can be sure of this in a few days - it will bloom.

Under the influence of cold, enzymes also begin to act differently in tissues and growth points: they transfer reserve substances from insoluble forms to soluble ones, for example, starch into sugar, which is why, by the beginning of winter, a lot of sugars and fats accumulate in the cells, protecting living tissue from the harmful effects of frost - their winter hardiness increases markedly. All life processes in them are aimed at increasing the resistance of tissues against adverse conditions.

Flower buds usually enter winter already with the rudiments of sepals, petals, stamens, and also pistils. This completes the first, summer-autumn stage of their development, although the change in their requirements for nutritional conditions, for the concentration of cell sap, as studies have shown, occurs much earlier, as early as late summer - early autumn. And the signs of change here are not external morphological changes in the cones of growth - they are not difficult to establish by looking at the longitudinal section of the kidney through a strong magnifying glass - but internal qualitative changes in the cells. Under favorable conditions, they pass 20-25 days before the appearance visible changes in the cone of growth and the beginning of the formation of flower organs in it.
The further development of flower buds proceeds normally only on the basis of qualitative changes characteristic of the second stage of their development, which requires a good saturation of the cells with water. But since they usually have such a condition only in spring, the flowers begin to actively develop only after the spring awakening of the buds. In autumn, their growth is more and more inhibited by the relatively high concentration of cell sap in the growth cones, and then by increasingly severe cold. Therefore, instead of 25-30 days (under favorable conditions), this period lasts five to six months or longer.

It has long been noted that for the normal development of flower buds, for example, in plums, at least two months of relative “cold” are needed. Further studies showed that some kind of qualitative "jump", a turning point in the formation of flowers, for which low temperature, No. That is, in itself, as an obligatory factor in development, it is not required for them, but if the kidneys have already entered a period of rest, then they need exposure to cold to restore normal vital activity.
But the roots of trees and shrubs continue to work very actively almost everywhere in late autumn, especially if the near-trunk circles and aisles of the garden were well mulched: the cold then penetrates slowly into the depths of the soil. At 5-10 degrees of heat, they feel good, absorb and accumulate nutrients in their tissues, since there is almost always enough moisture in the soil at this time. It is good to add at least a small amount of wood ash, mineral fertilizers, humus to the trunk circles, if this has not been done before.

To disinfect the garden, it is useful to spray them with a 4% solution of urea (400 grams per 10 liters of water). It is better to rake the fallen leaves without such treatment, and not only under apple trees, pears, plums, but also under birches, lindens, willows, mountain ash growing near the house, and sprinkle the soil with a stronger 7% urea solution. First of all, such processing should be carried out under dwarf apple trees - they are more vulnerable than others, as well as in the aisles of strawberries and strawberries, under young and newly planted trees, and the soil should be harrowed.

Long before cold. cloudy, changeable late fall in middle lane. Having laid bare the garden, she only in some places on the tops of the shoots of the most heat-loving late varieties still left browned leaves that did not have time to fully bloom. The garden brightened and emptied.

The frost resistance of plants is a changing property. It develops throughout the growing season, but especially strongly - at the end of summer and autumn. Its first stage is the weakening and cessation of growth processes, the transition to a state of rest. The second is the beginning of hardening.

By the time of leaf fall, the tissues and organs of plants are filled with starch, which hydrolyzes (splits) when the temperature drops. The resulting sugar, as well as fats, are consumed in winter. are changing physical properties protoplasm, and growth is completely inhibited. After such preparation, the slow increase in frost does not threaten the plant.
So, winter hardiness is determined not only by the properties of growing tissues, but also by the course of metabolism, which ensures the processes of vegetation and the transition of the plant to a new physiological state, which gives the tissues the ability to endure low temperatures.

AT last years in the middle zone of steel, it is widely grown varieties of a high-intensity type, very whimsical and demanding on the conditions of agricultural technology. Some of them are imported from places with a milder climate or from abroad. Their frost resistance, as tests have shown, is noticeably lower than that of old Russian varieties. And this cannot be ignored.
Some varieties, painfully enduring severe frosts, often freeze slightly and suffer in relatively mild winters, but with sharp drops in temperature after thaws. That's why essential feature varieties can be considered its ability to maintain high frost resistance after thaws. Studies have shown that the bark and cambium of trees of old Central Russian varieties are more resistant to frost after thaws than those of foreign and new breeding varieties. However, it should be noted that the varieties Wellsey, Mayak, Vityaz, Voskhod turned out to be more stable than others. Trees of the varieties Lobo, Vityaz and Mantet are not inferior to Pepin saffron in terms of frost resistance, but their regenerative ability is different: in Lobo it is good, in Vityaz and Mantet it is weak.

But no matter how successful the hardening of horticultural crops is, even in the fall, when the rainy season ends, in the second half of November it is very useful to inspect all the trees and bushes, establish damaged places, clean them of dirt and litter, cover them with garden pitch, put them under the branches "winter" chatals in order to protect them from breaking after heavy snowfalls. It is also important to remove from the trellis in a timely manner, lay on the ground and shelter from the cold climbing plants - actinidia, lemongrass, grapes, blackberries, climbing and other roses. Until the raspberry shoots are frozen and brittle, they are carefully bent along the rows to the ground and fixed in such a position that by the time severe frosts they were completely covered in snow. With the help of slats and pegs, it is advisable to press and “spread” bushes of gooseberries, golden currants, mock oranges and other shrubs that do not have a sufficiently high winter hardiness in the middle lane below the ground. After the first snowfalls, it is useful to cover them with snow in the same way as young trees of apple trees, pears, cherries, plums. And in the conditions of the Urals and Siberia, all Stlans require shelter with snow, which is called "with a head." In the snowy, air-filled "openwork" mass, the plant does not experience sharp temperature fluctuations that reduce its frost resistance.

In late autumn and early winter, the ground, where there is no snow cover or it is very thin, can freeze strongly and deeply, which leads to damage to the root system of trees. To prevent this, the trunk circles are insulated with mulch, and after the first snowfall they are covered with snow.