From the life of our deciduous trees and shrubs in early spring - spring and autumn in the life of plants. Walk "The first leaves on the trees The appearance of leaves on the trees in spring
When the days become shorter, and the sun no longer generously shares its warmth with the earth, one of the most beautiful seasons of the year comes - autumn. She, like a mysterious sorceress, changes the world around and fills it with rich and unusual colors. Most notably, these miracles occur with plants and shrubs. They are among the first to respond to weather changes and the onset of autumn. They have three whole months ahead of them to prepare for winter and part with their main decorations - leaves. However, at first, the trees will certainly please everyone around with their play of colors and the frenzy of colors, and the fallen leaves will carefully cover the earth with their veil and protect its smallest inhabitants from severe frosts.
Autumn changes with trees and shrubs, the causes of these phenomena
In autumn, one of the most important changes in the life of trees and shrubs occurs: a change in the color of the foliage and leaf fall. Each of these phenomena helps them prepare for winter and survive such a harsh season.
For deciduous trees and shrubs, one of the main problems in the winter season is the lack of moisture, so in autumn everything useful material begin to accumulate in the roots and core, and the leaves fall off. Leaf fall helps not only to increase moisture reserves, but also to save them. The fact is that the leaves evaporate the liquid very strongly, which is very wasteful in winter. Coniferous trees, in turn, can afford to show off with needles in the cold season, since the evaporation of liquid from them is very slow.
Another reason for leaf fall is the high risk for branches to be broken under the pressure of a snow cap. If fluffy snow fell not only on the branches themselves, but also on their leaves, they would not withstand such a heavy burden.
In addition, many harmful substances accumulate in the leaves over time, which can only be eliminated during leaf fall.
One of the recently uncovered mysteries is the fact that deciduous trees placed in a warm environment, and therefore not in need of preparation for cold weather, also shed their leaves. This suggests that leaf fall is associated not so much with the change of seasons and preparation for winter, but is an important part of life cycle trees and shrubs.
Why do leaves change color in autumn?
With the onset of autumn, trees and shrubs decide to change the emerald color of their leaves to brighter and more unusual colors. At the same time, each tree has its own set of pigments - "paints". These changes are due to the fact that the leaves contain a special substance, chlorophyll, which converts light into nutrients and gives the foliage a green color. When a tree or shrub begins to store moisture, and it no longer reaches the emerald leaves, and the sunny day becomes much shorter, chlorophyll begins to break down into other pigments, which give the autumn world crimson and golden tones.
The brightness of autumn colors depends on the weather conditions. If the weather is sunny and relatively warm, then the autumn leaves will be bright and variegated, and if it rains often, then brown or dull yellow.
How the leaves of different trees and shrubs change color in autumn
Autumn owes its riot of colors and their unearthly beauty to the fact that the foliage of all trees has different combinations of colors and shades. The most common purple color of the leaves. Maple and aspen can boast of crimson color. These trees are very beautiful in autumn.
Birch leaves become light yellow, and oak, ash, linden, hornbeam and hazel - brownish yellow.
Hazel (hazel)
Poplar quickly sheds its foliage, it is just beginning to gain yellowness and has already fallen.
Shrubs also delight with the variety and brightness of colors. Their foliage turns yellow, purple or red. Grape leaves (grape - shrub) acquire a unique dark purple color.
The leaves of barberry and cherry stand out against the general background with a crimson-red tint.
Barberry
From yellow to red, rowan leaves can be in autumn.
The leaves of the viburnum turn red along with the berries.
Euonymus dresses in purple clothes.
Red and purple shades of foliage determines the pigment anthocyanin. An interesting fact is that it is completely absent in the composition of the leaves and can only be formed under the influence of cold. This means that the colder the days, the more crimson the surrounding leafy world will be.
However, there are plants that, not only in autumn, but also in winter, retain their foliage and remain green. Thanks to such trees and shrubs, the winter landscape comes to life, and many animals and birds find their home in them. In the northern regions, such trees include trees: pine, spruce and cedar. To the south, the number of such plants is even greater. Among them, trees and shrubs are distinguished: juniper, myrtle, thuja, barberry, cypress, boxwood, mountain laurel, abelia.
Evergreen tree - spruce
Some deciduous shrubs also do not part with their emerald clothes. These include cranberries and cranberries. In the Far East there is an interesting wild rosemary plant, the leaves of which do not change color in autumn, but curl up into a tube in autumn and fall off.
Why do the leaves fall, but there are no needles?
Leaves play an important role in the life of trees and shrubs. They help create and store nutrients, as well as accumulate mineral components. However, in winter, when there is an acute shortage of light, and, therefore, nutrition, the leaves only increase the consumption of useful components and cause excessive evaporation of moisture.
Coniferous plants, which most often grow in areas with a rather harsh climate, are in great need of nutrition, so they do not shed their needles that act as leaves. The needles are perfectly adapted to the cold. The needles contain a lot of chlorophyll pigment, which converts nutrients from light. In addition, they have a small area, which significantly reduces the evaporation from their surface of much-needed moisture in winter. From the cold, the needles are protected by a special wax coating, and thanks to the substance they contain, they do not freeze even in severe frosts. The air that the needles capture creates a kind of insulating layer around the tree.
The only coniferous plant that leaves its needles for the winter is larch. It appeared in ancient times, when summers were very hot and winters were incredibly frosty. This feature of the climate led to the fact that the larch began to shed its needles and it was not necessary to protect them from the cold.
Leaf fall, as a seasonal phenomenon, occurs for each plant at its own specific time. It depends on the type of tree, its age and climate.
First of all, poplar and oak part with their leaves, then the time of mountain ash comes. The apple tree is one of the last to shed its leaves, and even in winter, it may still have a few leaves.
Poplar leaf fall begins at the end of September, and by mid-October it completely ends. Young trees retain their foliage longer and turn yellow later.
Oak begins to lose its leaves in early September and completely loses its crown in a month. If frosts begin earlier, then leaf fall occurs much faster. Along with oak leaves, acorns also begin to crumble.
Mountain ash begins its leaf fall in early October and continues to delight with its pink leaves until November 1. It is believed that after the mountain ash parted with the last leaves, dank chilly days begin.
The leaves on the apple tree begin to turn golden by September 20. By the end of this month, leaf fall begins. The last leaves fall from the apple tree in the second half of October.
Evergreens and shrubs do not lose their foliage even with the onset of cold weather, as ordinary hardwoods do. Permanent leaf cover allows them to survive any weather conditions and retain the maximum supply of nutrients. Of course, such trees and shrubs renew their leaves, but this process occurs gradually and almost imperceptibly.
Evergreens do not shed all their leaves at once for several reasons. Firstly, then they do not have to spend large reserves of nutrients and energy to grow young leaves in the spring, and secondly, their constant presence ensures uninterrupted nutrition of the trunk and roots. Most often, evergreen trees and shrubs grow in areas with a mild and warm climate, where the weather is warm even in winter, however, they are also found in harsh climatic conditions. These plants are most common in tropical rainforests.
Evergreens such as cypresses, spruces, eucalyptus, some types of evergreen oaks, rhodendron can be found in a wide area from harsh Siberia to the forests of South America.
One of the most beautiful evergreens is the blue fan palm, which is native to California.
The Mediterranean oleander shrub is distinguished by an unusual appearance and a height of more than 3 meters.
Another evergreen shrub is the jasmine gardenia. Her homeland is China.
Autumn is one of the most beautiful and colorful seasons. Flashes of purple and golden leaves, preparing to cover the ground with a multi-colored carpet, coniferous trees piercing the first snow with their thin needles and evergreens, always pleasing to the eye, make the autumn world even more delightful and unforgettable. Nature is gradually preparing for winter and does not even suspect how fascinating these preparations are to the eye.
The tree that opens the flowering season is alder. Its inflorescences are inconspicuous, but nevertheless, during the period of mass flowering, they will certainly attract attention if we pass somewhere along the bank of a stream or near a ravine at this time, where alders are usually found. Even from a distance you can see the reddish tint of the tree crown. Coming closer, we will see a large number of drooping earrings, which, with the slightest tapping on the trunk or a breath of wind, will throw out whole clouds of yellow dust. In addition to these earrings, we will also find numerous black knobs on the alder. While the catkins are the male alder buds, these buds are last year's female buds that are still hanging on the tree and fall off only by early summer.
Almost simultaneously with the alder in early spring, when snowdrifts still lie in the depths of the forest, the hazel, or hazel, a common and well-known shrub in our forests, blooms on the edge, on the sun-baked slopes. However, hazel is popular only in autumn, when its fruits ripen; in the spring no one pays attention to him, especially when he stands in a leafless state. Meanwhile, just at this time, he is perhaps the most interesting in a biological sense. Hazel blossom is taken by some phenologists as the beginning of the third period of spring, which at this time finally comes into its own.
First flowering shrub 
Almost simultaneously with alder in early spring, when snowdrifts still lie in the depths of the forest, hazel, or hazel, a common and well-known shrub in our forests, blooms on the edge, on the sun-baked slopes. However, hazel is popular only in autumn, when its fruits ripen; in the spring no one pays attention to him, especially when he stands in a leafless state. Meanwhile, just at this time, he is perhaps the most interesting in a biological sense. Hazel blossom is taken by some phenologists as the beginning of the third period of spring, which at this time finally comes into its own. At this time, warm sunny days are usually already set, the snow melts quickly and awakening flora every day becomes more and more noticeable. If the birch and maple, with the beginning of their sap flow, seemed to catch the first glimpses of the coming spring, then the modest flowers of the hazel mark its complete reversal, the final victory over winter.
Early flowering of hazel, as well as alder, is possible only thanks to the advance preparation of its inflorescences. Throughout the winter, on its branches, we observe male earrings, in which there are fully formed flowers. They endure thirty-degree frosts, but as soon as they begin their development, they already become much more sensitive to lower temperatures and during the flowering period they often suffer from frost. The structure of male hazel earrings at first glance resembles the already familiar alder earrings.
The development of a flower earring in spring occurs with exceptional speed. As soon as the sun warms and the temperature rises, the earrings begin to crack, and the stem on which the flowers sit stretches and grows almost before our eyes. So, for example, on a cut branch of a hazel in a humid chamber, the stem of a male earring elongated by as much as 3 cm in a day. The rate of anther cracking is closely dependent on the degree of air humidity. In a humid atmosphere, the opening of the anthers is delayed for several days, but if the earring is moved to a dry place, it occurs in half an hour. This circumstance is of great importance in the life of the plant. It allows him, as it were, to wait out rainy weather and postpone flowering until a more favorable time. However, in rainy weather, the already opened gaps of the anthers have the ability to close again. It also significantly reduces waste of pollen. The amount of pollen released by hazel trees during the flowering period is enormous. One earring of it gives about 4 million pollen grains, and if we assume that there will be at least a hundred such earrings on an average bush, but in fact much more, then one can imagine what a colossal amount of tiny dust particles is carried in the air in spring in our forests. Let us now turn to the female hazel flowers. Unlike males, they are hidden in the kidney in winter and become noticeable only in spring, when purple tassels of stigmas appear from the scales.
Does the intense red color of the stigmas have any biological significance? Many probably paid attention to the fact that young leaves developing from buds in spring, or sprouts of herbaceous perennials are bright red in color. It is clearly visible on large sprouts of horse sorrel or on young leaves of maple, cherry or oak. This red color is due to the presence in plant tissues of a special pigment - anthocyanin, dissolved in cell sap. We will dwell on it in more detail in the chapter on leaf fall, and now we will point out that anthocyanin is currently ascribed the role of an additional trap from the wind. By absorbing the green and blue rays of the spectrum, it contributes to an increase in the temperature in the cells, which in the cool spring time has great importance. It is believed that the intense pink color of the stigmas of hazel, as well as the purple color of the female alder inflorescences, thus accelerates the germination of pollen on the stigmas, which occurs more vigorously under conditions of elevated temperature.
When buds are laid at the hazel
Deployment of leaves in hazel occurs much later than its flowering. Only after the male earrings have dusted off, darken, dry up and begin to fall off the branches, the buds begin to bloom, covering the shrub with a delicate green haze. Why do leaf buds open much later than female flower buds or male catkins? Why is the development of our shrub proceeding with such a regular sequence, first opening its huge flowers, and then dressing in its green attire? It can be assumed that in hazel, as in most of our other trees and shrubs that bloom before leafing out, the development of flower and the development of vegetative buds are different stages, the onset of which requires different temperature conditions. The deployment of vegetative buds requires much more heat than the development of flower buds. Hazel buds, having begun their development, subsequently bloom extremely quickly, since all the necessary parts have been laid in them since the previous year. This bud formation takes place much earlier than is usually imagined, and already in the middle of summer, in most of our trees and shrubs, fully formed buds can always be found on young shoots. So, for example, on May 25, buds consisting of 6-10 scales were observed on young growing shoots of hazel. On June 10, there were already 12-14 scales on these buds, but leaf primordia were not yet noticeable among them. They appeared in the buds in early July, first in the amount of one or two, and by August 11 the next 2-3 leaves had developed.
It is remarkable that already at that time in the axils of these tiny leaves, under strong magnification, small buds of two to four scales could be found. These bud primordia must therefore overwinter twice before they begin their development. This is how long the hazel buds go through before they become noticeable or we pay attention to them!
What are kidney scales 
In most plants, for example, in willow, hawthorn, wild rose, etc., in adult leaves, we can distinguish three main parts - the leaf blade, which serves for light nutrition of plants, the petiole, which supports the leaf blade and attaches it to the stem, and, finally, stipules. Stipules usually look like two small leaves located at the base of the leaf petiole, and their purpose is not always clear at first glance. However, the significant role that they play in plant life becomes clear in the spring, when the buds on the trees begin to develop. It turns out that in hazel, as in most of our trees and shrubs, the bud scales, which play such a significant role in the life of plants in winter, are nothing more than stipules, which in the bud significantly outstrip their corresponding leaves in their development. At the hazel, the stipules fall off, having fulfilled their purpose, immediately after the shoot develops, and in the summer it is no longer possible to find them on the shoots. In linden, this fall of stipules at the time of leafing out is so noticeable that in linden forests in spring all the soil under the trees is strewn with pinkish or slightly greenish bud scales. In other trees, stipules persist throughout the life of the plant. They turn green and take part in assimilation. However, one should not think that in all our trees and shrubs the kidney scales are formed by stipules. The currant is completely devoid of stipules, and in its buds the scales are expanded leaf petioles. In horse chestnut, bud scales are modified leaf blades. This is not difficult to verify at the moment of blooming of its large buds, where you can easily observe all the transitions between bud scales and true leaves. We now know what the bud scales of the hazel are. Let's see how they are arranged. There is one interesting detail here. If we make a transverse section through the kidney scale and look at it under a microscope, we will find a special cavity inside. This cavity is filled with air, which is known to be a very poor conductor of heat. As a result, the protective role of scales increases, which protect delicate leaf primordia from sudden temperature fluctuations.
After the shoot of the hazel finishes its development - flowering, deployment of growth buds, growth of shoots and the laying of new buds, we will not notice further significant changes. Nevertheless, important processes of seed maturation in fertilized ovaries and the deposition of reserve substances in leaf buds and flower male catkins take place in summer, which ensures their development next spring.
Seed ripening in hazel is extremely slow. Despite the fact that this shrub blooms extremely early, its fruits fully ripen only by September. In this it differs sharply from our other trees and shrubs, the fruiting period of which is much shorter. It is especially curious that the period of fruit ripening in willow and aspen usually does not exceed a month, while in hazel it averages four months. It is difficult to say what these features of the fruiting of various plants are connected with, however, in the future we will partially return to this issue.
Our willows in early spring
In early spring among our wind pollinated trees and bushes, hung with modest, nondescript catkins, flowering bushes of willows attract attention from afar. At this time, against the gray, still transparent background of the forest, bright yellow willow inflorescences stand out sharply, densely covered with sticky pollen and emitting a delicate and pleasant aroma. However, long before flowering, many willows, especially red willow, become quite noticeable due to their graceful fluffy inflorescences, known as "lambs". The sudden appearance of these "lambs" in the middle of winter, in January or February, is one of the most curious phenomena in the life of our spring nature. However, before getting acquainted with the vital characteristics of willows, it should be noted that we have a large number of species. In total, in the flora of the USSR, there are currently about 170 species of willows, and in the Moscow region alone, their number reaches 40. With such a variety of species, willows have the ability to give hybrids with each other, and often double and triple. At present, even five and six hybrids are known, which are extremely difficult to understand. We will have in mind only some of the most famous and common willows among those that bloom in early spring before the leaves bloom. This includes the well-known red willow, or red willow (Salix purpurea), common in the south of the European part of the USSR, reaching in the north to the southern border of the Moscow region and introduced into culture; goat willow, or bred willow (Salix caprea), ubiquitous in forests, and ash willow (S. cinerea), growing in damp places in most of the USSR. Other willows that are widespread in our country, such as the white willow (Salix alba) or the brittle willow (Salix fragilis), growing along the banks of ponds and near dwellings in the form of large weeping trees, bloom much later, simultaneously with the development of young leaves.
When willow flower buds awaken from their winter sleep 
The dormant period of our early willows lasts until mid-January. Until this time, their kidneys are densely scaled and do not show any noticeable changes. However, starting from the end of January, flower buds begin to show undoubted signs of incipient development. The caps crack at the very base and, not being able to embrace the swelling flower earring, gradually move towards its top or to the side, and then completely fall off. However, this process proceeds at an extremely slow pace and usually ends completely only by the second half of March.
The dropping of caps in our early willows is an extremely interesting phenomenon. In February, there are the lowest temperatures, twenty-degree frosts often crack and the soil freezes on maximum depth. Nevertheless, the swelling of flower catkins undoubtedly indicates the beginning of the development of plants, their exit from winter stupor. The life of our trees in winter has not yet been studied enough, but there is reason to believe that during periods of thaw and on warm sunny days, sap flow begins in individual branches of willows. In them, the transformation of spare substances takes place and they move to the kidneys from various parts of the crown and trunk.
Let us now follow further the development of flower catkins in the willow. Having thrown off their caps, they look like elegant, fluffy white balls, similar from a distance to small tufts of cotton wool. What do their numerous hairs represent? It is best to answer this question at the time of flowering willow. At this time, it is easy to see that willow inflorescences are of two varieties: both male and female, and they are located on different bushes in such a way that on one bush there are only male earrings, and on the other - female.
Male willow flowers are built very simply. They are devoid of perianth and are covered with only one scale in the axil, in which there are usually two (some willows have more) stamens. The scales are usually two-colored: yellowish-green below, blackish above. The upper part of the scale is covered with long numerous hairs, which give the unflowered earring a characteristic fluffy appearance. The significance of these hairs in the life of the plant is quite clear. Dressing the buds like a fur coat, they give them the opportunity to endure low temperatures and its sharp fluctuations without any harm at a time when the caps covering them fall off. Female flowers of willows have a similar structure, except that instead of stamens there is an oblong ovary thickened downwards, resembling a bottle in shape. This ovary at the top passes into a style with a bifid stigma, the sticky surface of which catches the pollen that falls on it. In addition to scales, stamens and pistils, male and female willow flowers have special nectaries at the base of the covering scales that secrete sweet juice-nectar. Willows, unlike most of our other early-flowering trees and shrubs, are pollinated with the help of insects, which are attracted, on the one hand, by fragrant nectar, and on the other, by a large amount of pollen, densely sticking to flower earrings during the flowering period.
Such a simple structure of flowers in our willows, devoid of any trace of perianth, somehow does not fit with their method of pollination; in addition, all the rest, by the way, more ancient representatives of the willow family - various poplars and aspens - are typical wind-pollinated plants. Therefore, it is now believed that willows are secondarily adapted for pollination with the help of insects, and this adaptation could have arisen in relatively recent times. This is indicated, among other things, by the large number of species of insects that visit willow flowers, reaching up to eighty. Among them we will meet bumblebees, ordinary and earthen bees, butterflies and some flies. This diverse range of pollinators indicates that willows do not have a particular specialization in this direction, while the flowers of most other entomophilous plants are strictly adapted to a particular species or group of insects. We will explore some of these devices in the next chapter.
It is also interesting to note that at present there is reason to believe that the ancestors of our willows had bisexual flowers, as indicated by the not so rare appearance of special freaks in the goat willow in the form of flowers that have both a pistil and a stamen. It is possible that the transition to dioecy gave willows a number of advantages in terms of protection against self-pollination. However, all this still remains in the area of the most remote assumptions.
Seasons are seasons that differ in weather and temperature. They change with the annual cycle. Plants and animals adapt perfectly to these seasonal changes.
It is never very cold or very hot in the tropics, there are only two seasons: one is wet and rainy, the other is dry. At the equator (on the imaginary midline) it is hot and humid throughout the year.
In temperate zones (outside the lines of the tropics) there is spring, summer, autumn and winter.
Generally, the closer to the North or South Pole, the cooler the summer and the colder the winter.
For three spring months, nature has time to change beyond recognition. In March, she is just beginning to wake up from hibernation. The spring warmth is not enough to make the snow and ice blocks melt, but the air gradually warms up, preparing all living things for a gradual awakening, the first cumulus clouds appear, which are still very high.
Astronomers consider the beginning of spring to be March 21-22 - the moment of the vernal equinox, when the day is equal to the night, and the end - June 21-22 - the longest days of the year.
For naturalists, spring begins with the arrival of rooks (March 19 on average) and the movement of sap near the Norway maple (March 25).
This season is conditionally divided into three periods: early spring- before the snow melts in the fields (until mid-April), middle spring - before bird cherry blooms (until mid-May) and late spring - before apple and lilac trees bloom (until early June).
Phenomena in inanimate nature.
In the second half of March, the days noticeably lengthen, the nights decrease; the sun rises higher and higher at noon above the horizon, its rays fall more directly on the earth and warm it more strongly. The snow becomes loose, begins to melt, and on open places thaws are formed.
In the second half of March, the first cumulus clouds appear.
They are very beautiful, they look like snow-white, dome-shaped masses with even bases. Clouds usually arise in the morning or at noon due to the heating of the air adjacent to the earth; towards evening, when the ascending currents weaken, they begin to disappear, to melt.
In the first half of April come off the ground snow; streams formed during its melting run down to reservoirs.
Ice drift usually begins in mid-April. Shortly before this, rims appear near the shore - narrow strips of water. Under the influence of water and the sun, cracks form in the ice, it breaks up and starts to move. Ice floes, crowding and pushing, rush down the river, hitting the banks and piles of bridges. In the middle of the river, ice floes move faster than near the banks. They melt along the way. The river is freed from the ice cover, overflows its banks and overflows. The flood begins.
Usually in early May there is the first thunderstorm.
At this time and later, a sudden cold snap often occurs with frosts, from which plants suffer greatly, especially fruit and berry plants.
Spring awakening of trees. Soon after the appearance of thawed trees, trees wake up: they begin to flow sap. This phenomenon is revealed if the bark is pierced with a thick needle: a sweet transparent liquid flows out of the raki; in air, it oxidizes and acquires a reddish color.
Extraction of juice causes great harm to trees.
Sap flow is a complex physiological process. The roots begin to actively absorb water from the thawing soil, it dissolves the plant's winter nutrient reserves and moves in the form of a solution along the trunk and branches to the buds.
Swelling and bud break.
Top 16 primroses among shrubs and trees
Ten days after the start of sap flow, swelling of the buds becomes noticeable, in which rudimentary shoots are located under the protective bud scales.
Trees and shrubs, pollinated by the wind, bloom before they are covered with leaves, or at the very beginning of their deployment.
Alder and hazel are the first to bloom in the second half of April, and willow is among those pollinated by insects. Willow buds are densely tightened with brown scales that look like caps.
Having dropped them, the buds look like fluffy balls, consisting of hairs that protect the flowers from sharp fluctuations in temperature and rain.
In April, most of the trees are still bare, but the integumentary scales of the swollen buds are already moving apart, and the tailbones of the leaves are showing from them.
The appearance of leaves. The young leaves of some trees are covered with a sticky fragrant substance, while others have a fluff that protects them from the cold.
Gentle and transparent at this time is the light green outfit of the trees.
At the end of April, bird cherry and birch buds bloom; in the first half of May - buds of maple, yellow acacia, apple and pear, and then - oak and linden.
In late spring, in the second half of May, the real flowering of spring begins. Bird cherry blossoms, at the same time - blackcurrant, a little later - wild strawberries and fruit trees, lilac, mountain ash and most herbaceous plants.
In the last days of May, the fruits of aspen and willow ripen.
The petals of apple and lilac flowers fall off - spring ends, summer begins.
Biology Spring phenomena in plant life
Spring is the time for the awakening of nature. According to the calendar, spring begins on March 1. In nature, spring comes into its own with the beginning of sap flow in trees, earlier in the south, and later on March 1 in the north.
The spring movement of juices near trees and shrubs is the first sign of spring. It comes after the soil thaws and water from the roots begins to flow into all organs of the plant. At that time leaves not yet.
Water accumulating in cells stems of plants, dissolves stored in them organic matter. These solutions move to the swollen and blooming kidneys. Already at the beginning of March, earlier than in other trees, the spring sap flow begins in the Norway maple, a little later in the birch.
The second sign of spring is the flowering of wind-pollinated trees and shrubs.
The gray alder blooms first in the middle zone of the European part of the USSR. Its flowers are inconspicuous, but the blossoming earrings of staminate flowers are clearly visible. 123
. One has only to touch an alder branch with catkins, as the wind picks up a whole cloud of yellow pollen. 
Pistillate alder flowers are collected in small grayish-green inflorescences. Next to them, dry, blackened cones of last year's inflorescences are usually clearly visible.
Almost simultaneously with the alder, the hazel, which you met in the fall, blooms.
Hazel staminate flowers develop in inflorescences - complex catkins, and reddish stigmas of pistillate flowers protrude from generative (flower) buds.
Early flowering of alder, hazel and other wind-pollinated plants- good adaptation to life in the forest.
Bare leafless branches do not impede pollination. Pollen, picked up by the wind, is freely transferred from one plant to another.
Flowering coltsfoot is also a sign of the coming spring. This perennial herbaceous plant grows in open, sunlit places, on railway embankments, river banks, steep slopes and cliffs.
As soon as the snow melts, its scaly stems already appear - flower stalks with bright yellow inflorescences, similar to dandelion inflorescences 124
. The large leaves of the coltsfoot grow after its fluffy fruitlets have ripened and scattered. 
The coltsfoot received its unusual name for the originality of the leaves. Their underside is covered with white, soft, like felt, hairs, and the upper side of the leaves is smooth and cold.
The coltsfoot blooms in early spring, before the leaves bloom, perhaps because its thick, long rhizomes have accumulated reserves of nutrients deposited in the summer of last year.
Feeding on these reserves, flower plants grow shoots and fruits are produced.
The third sign of spring is the flowering of perennial herbaceous plants of the deciduous forest. In the districts middle lane they bloom almost simultaneously with the coltsfoot. The first to bloom in the forest are the noble liverwort with azure flowers and the medicinal lungwort, then the oak and buttercup anemones 125 , Corydalis 119 , spring chistyak 126 , spring primrose 127 .
Flowering shrubs in spring
All of them are photophilous and bloom under the canopy of the forest, when there are no foliage on the trees and shrubs yet.
In the life of some early-flowering herbaceous plants of the forest, their growth under snow is very interesting. Plants such as the blueberry, or snowdrop, grow even in winter under the snow.
In the spring, many of them come out from under the snow with green leaves and with buds formed last fall.
Οʜᴎ often bloom before the snow melts 128 . That is why these plants are called snowdrops.
Plants that bloom in early spring always attract attention because they are beautiful and because after a long winter they are the first flowering plants. Unfortunately, they are often collected, making up large bouquets. Often they destroy entire plants, pulling them out with roots. Plants with flower-bearing shoots torn off do not produce fruits and seeds.
This makes it difficult for them to reproduce. Many of the plants have become very rare, for example, noble liverwort, sleep-grass. They cannot be allowed to disappear completely. We must take care of the preservation of plants, not tear them in order to throw them away in a day, not damage wild plants and actively protect nature.
Protection of Nature and rational use natural resources of the country are legalized by the Constitution of Russia, i.e.
e. obligatory for all citizens of our country.
Trees and shrubs pollinated by insects bloom later, after the leaves bloom. If you observe the course of spring from year to year, you will be able to establish the sequence of spring development of plants.
In the middle zone of the European part of the USSR, usually 8 days after the flowering of the coltsfoot, lungwort begins to bloom, after 21 days - dandelion and willow-willow.
The pear blossoms on the 29th day, the yellow acacia on the 30th, and the linden on the 75th day after the start of flowering of the coltsfoot.
Every year the spring phenomena come in strict order. For example, lungwort always blooms later than coltsfoot, but before dandelion.
Observations of spring phenomena in the life of plants help to establish the best dates for agricultural work and to prepare for them in a timely manner.
For example, it is known: in the regions of the middle lane best harvest cucumbers are obtained by sowing their seeds during the flowering of lilac and yellow acacia, and the best crop of turnips and beets is obtained by sowing them during the flowering of aspen.
Knowing how many days after the coltsfoot blooms lilacs bloom, it is easy to set the time for sowing cucumbers and prepare for it.
Spring. Spring months. Spring phenomena of nature. Spring weather signs.
Answer left Guest
Signs of spring in inanimate nature:
1) The main sign of spring in inanimate nature is that the sun rises much higher above the horizon than in winter.
2) It shines brighter and warms more and more every day.
The days are getting longer.
3) The most noticeable sign of the onset of spring in inanimate nature is the melting of snow.
4) The ice starts to melt. Ice starts on the rivers.
5) It is very dangerous to walk on melted ice. You can not start games on the river during the ice drift.
6) When rivers and lakes overflow with water from melted snow, water fills meadows, forests, fields along the river.
This is called a flood.
7) The soil thaws from the spring heat. It accumulates a lot of moisture. This moisture is very necessary for plants.
8) It rains in spring, not snow. Not far from the first thunderstorm.
Signs of spring in wildlife:
a) in the life of birds with the advent of spring: migratory birds return, build nests, lay eggs, hatch chicks
Such changes have become possible because many birds feed on insects. And with the advent of spring, insects crawl out of their hiding places.
The birds got more food. The ice on the rivers and lakes has melted, so waterfowl are returning
b) in the life of animals: Animals shed - they change their winter coats for summer ones. Bears, badgers, hedgehogs, chipmunks wake up from winter sleep.
Many animals have cubs in the spring.
c) Buds swell on deciduous trees and shrubs; earrings, silvery lambs, flowers appear, then leaves appear. Coniferous trees change the color of the bark, needles.
The ground is covered with young grass, many plants begin to bloom. Usually, early-flowering herbaceous plants are called snowdrops.
if everything is short:
The sun is higher than in winter. The days got longer. It got warmer outside. The sky in spring is blue and high.
The clouds are white and light. Snow and ice are melting. On the rivers ice drift, flood. In the spring, in different months, it snows, then it rains. In May, the first thunderstorm rumbles. The soil thaws, buds appear on the trees, and then sticky leaves. Primroses bloom. Insects appear. The migratory birds are returning. Forest animals breed offspring.
- familiarization with the change in trees and shrubs, with the change in buds.
Lesson progress:
I. Organization of attention.
Updating what has already been learned.
- What are the mushrooms that we meet in the forest consist of?
What is the name of the underground part of the fungus?
- Do you need a fly agaric?
Who is it useful for?
- What mushrooms can not be collected?
What should be done to avoid damage to the mycelium?
- Is it possible to collect old mushrooms?
But someone important
On a white leg.
He is wearing a red hat
The hat has polka dots.
Learning new.
1. Communication of the topic and purpose of the lesson.
It is impossible to imagine our nature without the white-trunk beauty of the birch. How many fairy tales, poems, songs have been composed about her? It is interesting that birch is the only tree in Russia with white bark that lives
birch 100 - 120 years old. Yes, people love birch, but how often do they not take care of it. Losing in the spring through the fault of man a considerable part of the juice, birch
If you inflict wounds on her for several years in a row, she can
die completely. Remember that the sugar contained in the juice is needed to feed the tree!
The movement of sap from trees and shrubs is a sign of their spring
awakening.
Another sign is the flowering of some trees and shrubs. Of the trees, the alder is the first to bloom. It is easy to recognize it in winter and spring by the black bumps on the branches. In the spring, earrings appear on the alder.
Which trees wake up first in spring? Urgently give 100 points
Earrings are many small flowers gathered together.
Willow blooms early in spring. Bees and bumblebees curl around its flowers. They come here for sweet nectar.
Of the shrubs, hazel and wolf's bast are the first to bloom. On hazel, as well as on alder, earrings are visible. And the wolf's bast is a poisonous plant.
All these plants are early flowering. They bloom before blooming
Birch blooms later, when the leaves on it are already beginning to bloom.
Even later, the bird cherry blossoms.
Swelling of buds and blooming of leaves is a sign of spring
awakening trees and shrubs.
Guys, interesting changes occur in the spring with conifers.
The larch is fully dressed with new needles. But coniferous plants never bloom.
Rules of friends of nature: do not damage the bark of trees, do not cut on
her letters.
Do not collect birch sap. Take care of the trees! Do not break branches of flowering trees and shrubs. Without flowers, there will be no fruits!
IV. Fizminutka.
V. Practical work.
- Unravel the ball. (Circle around)
- Writing straight lines with a rounding at the bottom.
- Shade the tree.
(The material is taken from the book Psychological and Pedagogical Support for the Life of a Child in the Conditions of Preschool Education (Part II)) - N.
In the spring, parents are usually visited by the desire to make young naturalists out of children. All the temptations are there: the birds are chirping, the grass is earing, everything is blooming. Spring is the best time to explore. the world, as they say, in kind, and not through the screen.
However, before giving a child the joy of watching sprouts, ask yourself honestly, but do you yourself know how to distinguish a bird cherry leaf from a currant leaf? Not? Then let's practice.
Bird cherry leaves are wide and thin, such are shade-loving plants. The upper part of the leaf is matte, slightly wrinkled, and Bottom part bluish. There is a pointed tip and jagged edges, if you look closely you can see brown-red glands.
Plants with fleshy leaves, with hairs or very narrow leaves, like those of sea buckthorn, resist better high temperatures and loss of water.
By the way, the scientific name of sea buckthorn is translated from Greek as “shine for horses” - the skin of animals that fed on the leaves of the plant acquired a satin sheen.
"Toothy" currant leaves are not to be confused with others. They appear in late April - early May. At black currant each tooth of the leaf also ends with a white tip, so to speak, with a “claw”, and the leaf itself is rich green in color. By the way, few people know that currant leaves contain more vitamin C than the berries themselves.
Now is the time to watch how life is born in the garden after a long winter: how the buds on the trees appear, and then the leaves bloom from them. Explain why each tree or bush in your area has different leaves.
When the field research is over, you can generalize. Describe how environmental conditions change the shape of the leaf and the plant as a whole. For example, in a dry and sunny place, the leaves grow small and hard, for example, like an apricot.
Hello, friends!
Today we are waiting for a new issue of the biological finger theater with a question from why Arina and Katerina Lazarev, who was sent by their mother Tatyana, author of the blog "Together with Mom". The girls have already come to the rubric, and today we will deal with the botanical issue: Why do flowers appear on trees first and then leaves?
The elephant is already ringing the bell.
Chapter 1
Elephant: I declare a new representation of BioTOP open.
kaffir raven: BioTOP! Biotope! Hearing the case of pollination.
meerkat: We will fight the dust? I have just the right tail. If you rub it with a plastic comb and fluff it, dust easily collects on it. Like iron to a magnet.
Elephant: We will deal with the matter of dust another time. And now we will talk about pollen and its transfer from flower to flower.
meerkat (grumbled): Then the name "pollination" is inaccurate, it should have been called "pollination".
Dragonfly(rolls her eyes dreamily): How opportune that we will deal with pollination today! After all, my candidate, a great specialist in this problem, is flying to us. And what a glamorous pink color he has!
Galapagos Albatross: Not the tiny hummingbirds you're talking about, Dragonfly?
Dragonfly: Sometimes they are called "northern hummingbirds". But these are not birds.
A pink bullet flashed through the air. Something whistled past Owl's ear.
Owl(goggling eyes): Fathers! Shoot! Get down!
Everyone lay down in the grass, peering ahead. Nothing happened. But then an unfamiliar voice came from behind.
Voice: And what's in there? Are you looking for something interesting?
The mudskipper jumped in surprise. And the Elephant slowly turned back, her eyes converged to the bridge of her nose. There was a small bright pink spot in front of the trunk.
Dragonfly: Meet! This is my deputy! Hawk hawk.
Hawk hawk: Wine hawk. At your service!
Owl: Well, you have chosen a candidate for yourself, Dragonfly! Moth hawk - that's what the people call a drunkard. Not only is a drunkard, but also wine!
Kaffir Raven: Where was your head, Dragonfly, when we invited a candidate with bad habits to our team?
Elephant: What do you say in your defense, Wine hawk?
wine hawk(sang piercingly):
THE SONG OF THE WINE HAWK
(
I'm called the wine hawk,
But I only swear to you
What about deep drunkards,
As a class I do not belong!
I'm indifferent to braga
There is no truth in wine!
No cravings for beer
Alcohol is not for me.
I feed on nectar
Among the night flowers -
Their fragrant charms
Ready to surrender.
On vine leaves
I start life.
In honor of these wine berries,
Call me my friends!
Once a greedy clerk,
Suddenly regretted the ink:
He is the name "grape"
Reduced to "wine".
Fell victim to the bureaucrat
My noble family
Let's say guys
Boycott in vain!
Kaffir Raven: Wow, what a harmful clerk got caught!
Dragonfly: You see! He was slandered. The wine hawker is not a drunkard at all. He is the largest specialist in antecology!
mudskipper Q: What kind of science is this? Antenna?
orangutan: If my memory serves me, this is the science of flowering and pollination. After all, "anthos" is translated from Latin as "flower".
Wine hawker: Quite right, dear Orangutan!
Octopus: Then, you will definitely be able to say why trees first have leaves, and then flowers.
Chapter 2
Orangutan: I always wondered how the flowers manage to grow ahead of the leaves? After all, in order for flowers to appear, sugar must accumulate. And sugar, just, the leaves produce.
wine hawk: Flowering before leaves is obtained in those plants that have a supply of sugar.It takes a lot of sugar to produce pollen.In trees, such a reserve is in the branches.At a birch, for example.
meerkat(licking): Is that why birch sap is so sweet?
wine hawk: Absolutely right! In winter, the leaves of the trees fall. But before that, they give the branches all the sugar they have produced. Trees stand with bare branches, tall. They bloom in the spring when there are no or very few pollinators. Trees do not count on their help, but turn to the wind as a carrier of pollen. Therefore, the flowers of spring trees are very economical - odorless and nectar, small and inconspicuous, collected in earrings.
meerkat (mentally, hanging the birch with earrings): Something I did not notice on the birch earrings.
orangutan (noticing the expression on the face of the Meerkat): Earrings are not jewelry, but inflorescences that sway in the wind near birch, poplar, alder, aspen, hazel.
wine hawk: Yes, they are a bit like fluffy caterpillars.
orangutan (quickly glancing at another expression on Meerkat's squeamish face): Our Meerkat has a very vivid imagination.
Owl: You, Wine Hawk Moth, would be better off showing the Meerkat what these catkin inflorescences of yours actually look like. And then, he imagined caterpillars in earrings.
meerkat(looked suspiciously at Owl): Here and there. Earrings separately - caterpillars separately.
wine hawk(smiling): We can see such earrings only in spring, but I have photos.
The wine hawk showed photos of the inflorescence of the catkin.
Meerkat: Indeed, caterpillars! I have a riddle! Remember last time we learned
MYSTERY ABOUT INFLOWERING EARRING
(
On the birch: oh-oh-oh!
Who hung upside down?
These are caterpillars in a row,
Bent legs,
And swing, hang,
Scattering crumbs.
Dragonfly Q: Why do they have such a similar shape?
Wine hawker: It is very convenient for the pollen to spill out at the slightest breeze. After all, pollination in spring trees with catkins most often occurs with air currents.
Orangutan: Plants that are pollinated by the wind are called anemophilous.
Owl: Well, what kind of anthropoid are you! Simply put, wind pollinated plants.
Dragonfly: But, you are all talking about pollen. Does this mean that all the flowers in the earring are boys? After all, pollen is male cells.
wine hawk: Your assumption is correct, dear Dragonfly. Earrings are a convenient form for male inflorescences. And there is a lot of pollen in them.
Owl: You won't understand these trees. As soon as the snow melts, they are already blooming. Wait until it warms up.
wine hawk: But when it gets warmer, leaves will appear.
Owl: So what? Let them appear. What do they interfere with?
wine hawk Q: Let's do an experiment! Then we'll find out.
Chapter 3
Materials: Dark paper, white gouache or white corrector, adhesive tape, scissors, a plate of flour, tree branches, paper leaves, clothespins.
Attention! Experiment outside, or in the bathroom, as there will be flour everywhere.
1. On dark paper, draw white outlines of birch trees. Pay attention to the shape of the branches hanging down. Such branches sway better in the wind. Make two copies.
2. On the birch branches, stick pieces of adhesive tape, sticky side up. You can use double-sided tape, or roll one-sided into a ring. These pieces of adhesive tape will symbolize female birch flowers with pistils on which pollen should fall. Let's put one of the copies vertically, leaning against a support.
3 . Insert tree branches into clothespins or press down with a pebble. We put them at a distance of 50 cm in front of the picture with adhesive tape. These are our trees from which pollen will fly.
4. Put 1 teaspoon of flour on a plate. Flour will be our pollen. Let's bring the plate to the trees and forcefully blow on the flour, causing it to scatter in the direction of the painted grove.
5. Consider tape. Has flour stuck to it? How dusty is the background?
6. Cut out leaves from paper and use tape to attach them to the branches.
7. Let's replace the background grove with the second instance. Let's repeat the experiment with flour.
8. Compare results. And draw your own conclusions.
wine hawk: Right! You need to spend tens of times more pollen for pollination to occur. And there is not enough sugar for that.
orangutan: Those flowers that had time to open before the leaves appeared were more likely to produce seeds. Therefore, the trees bloom before the leaves appear.
meerkat: And now I understand why birches grow in whole groves! To make pollination easier.
Wine hawker: Wonderful observation! Well done! Wind pollinated plants grow in groups. And the pollen from the earrings begins to crumble at a certain time. For example, in the morning. This improves pollination efficiency and conserves pollen.
Dragonfly: And snowdrops are in a hurry to bloom until the leaves appear on the trees?
Wine hawker: That's right, dear Dragonfly. Snowdrops in the forest bloom as long as the light falls under the trees. Leaves will appear, create a shadow.
Octopus: But the wind blows wherever it pleases. Will self-pollination occur? After all, the seeds then turn out to be weak, unable to germinate?
Chapter 4
Orangutan:Self-pollination is an undesirable thing for a plant. Although there are some plants that self-pollinate normally. For example, peas. Another hoof. Self-pollination is a necessary measure.
wine hawk: Plants found interesting solutions to prevent self-pollination. They divided bisexual flowers into male and female.
meerkat: What is it like?
Wine hawker:
ABOUT MALE AND FEMALE FLOWERS
(
If a flower, people
There are pistil and stamens
He will be bisexual
Please take this into account!
If there are only stamens,
At the head - dust grains of dust.
We have such a flower
It's called male.
If the pistil is lonely -
We call the flower feminine.
wine hawk: Right! Or the flowers are separated by space. For example, female flowers grow on one tree, and male flowers on another. Like poplar, willow, nettle, date palm.
meerkat: Ah... So that's why my potted palm doesn't give dates! She can't pollinate.
Wine hawker: On date palm plantations, female plants are even grafted with twigs with male flowers.
mudskipper: That would be appreciated by the Angler! After all, people did what deep-sea anglers do. They have a small male, sticks to a huge female, and they grow together so as not to look for each other in the dark. So a man grafts a small twig of a male palm tree onto a huge female one.
Meerkat: This is how I need to do it! To grow a branch on my palm tree. Does the wind also pollinate the palm tree?
wine hawk: Wind, wind.
Owl: There is something wrong with you! I have seen more than once how bees and bumblebees collected pollen from spring trees! And you say that the wind pollinates them! Lies! Bees pollinate them!
Wine hawker: Dear Owl, the main thing for plants is that pollen gets on the pistil, and how this happens is a secondary issue. Often plants combine several methods. And let's, in order to resolve our dispute, we will ask the bee itself.
Chapter 5
Owl: Dear bee! Can I have you for a minute!
Bee: Hello!
Owl: I saw how you take pollen from trees in spring. So, bees partially pollinate birch, poplar, aspen?
Bee: Probably not. They have some strange pollen. Small, smooth, dry. No taste in it, no aroma. Dust particles slide off us, and do not stick. What a difference, dandelion pollen! Large, fragrant. It sticks easily into balls. You will fill full baskets with legs with it, and you will also bring it to the hive on a body.
Owl: But willow then, do you pollinate?
Bee: We pollinate the willow. She has tasty and sticky pollen. She sticks to us well.
Owl: Then why do you collect dry and tasteless pollen?
Bee: So, we take it, because there is nothing else. That's when the willow blooms, we switch to it. And so - on bezrybe and poplar fish.
Orangutan: In the spring, even starving spiders eat pollen that has fallen into the network.
Mud Jumper: Why do you need pollen, Bee? Don't bees collect nectar for honey?
Bee: We also take pollen. From pollen we make bread for children - perga. Without such bread, they will die.Most best flowers those that have nectar and pollen! They are noticeable from afar both in appearance and aroma. They give both honey and perga for the bees.
mudskipper (speaking to the orangutan): And what are these flowers called correctly?
orangutan:Entomophilous.
Owl: And in a simple way - insect infested.
Bee: I have no time to chat with you! I flew.
Chapter 6
The bee flew away, and from somewhere in the grass a voice was heard:
mudskipper (bouncing): Oh, talking wire!
SONG OF THE DODDLE
(
I consider the leaves to be a flaw,
I hate green.
And I won't be photosynthesising
I get myself lunch!
I am not a green peasant.
Stronghold of the aristocracy!
Let me in the hot sun
The green rabble is working!
I'm proud of my roots
They rise above the earth
And become a thin princess
Outshine the plants!
Orangutan:Dear Dodder, I'm afraid you have no place in our clearing.
Elephant: Care to explain your words, Orangutan? Why are you oppressing the lady?
Dodder(squirming): I protest! I will complain! Give me a complaint book!
Albatross flew away with Dodder in its beak.
Elephant: Here is the insidious person Dodder! But, Kaffir Raven, write down a valuable thought. We should start a book of complaints and suggestions. We must not be separated from the people!
Wine hawker: Have you tried mango? Now, if you strengthen its specific bad smell, you get the smell of bats. After all, mangoes are pollinated by flying dogs, and they also distribute the fruits.
meerkat (rolling eyes thoughtfully): Flying dogs....
Owl(looking at Meerkat's face): Bat dogs are big bats.
meerkat: Dogs?
Owl (waving a wing at Meerkat): It will be necessary to pay attention to the mango. Mouse is good.
mudskipper: What are the names of flowers pollinated by bats?
orangutan: Chiropterophilic.
Owl: You will break your tongue. Chiroptero...
Wine hawker: In the 18th century, there lived a talented scientist Erasmus Darwin, who wrote an amazing botanical poem "The Love of Flowers", it is just about the secrets of flowers and their pollination.
Owl: Is he a relative of the same Darwin who wrote about evolution?
Wine hawker: Erasmus Darwin is his grandfather. And I have in store, written in his style.
The wine hawker began to recite poetry, but not everyone understood high poetry. And the Meerkat listened to the images with such an expression on his face that the Elephant was worried about his vivid imagination. As soon as the poems ended, Meerkat rushed off to look at the pollen of flowers under a microscope, hoping to see ships and horses in it.
Owl: Now try to separate the knights from the pollen for the Meerkat.
Dragonfly: How much we learned today that everything is messed up!
Kaffir Raven: No problem! I wrote everything down! I know how to sort out all the signs of pollination of flowers. Let's play one very interesting game "POLLINATION".
Elephant: Let's play! Let's play! I declare the show closed!
Botanical game "POLLINATION"
Rules of the game: The game is designed for 2-5 players. It is possible to increase the number of players by duplicating fields with signs of pollination.
1.
Print out the fields. If necessary, print the fields with characteristics.
2
. Glue three cubes with signs for pollination in flowers. Or glue the names of the features on the edge of a plastic or wood cube.
3
. Distribute one board with the traits per player: "Wind Pollination", "Water Pollination", "Insect Pollination", "Bird Pollination", "Bat Pollination".
4.
Throw three dice at the same time, and if the sign on the edge coincides with the sign on the player's field, the cell next to it is closed with a flower chip.
5
. The player's task is to collect all the signs for the plant as quickly as possible.
PS: On the "wind pollinated" field, to equalize the chances, you need to collect only 5 signs out of 7.
DOWNLOAD THE GAME "POllination" FROM THE BLOG "MAGIC OF BIOLOGY" FOR FREE.
Here is another question solved in the BioTOP finger biological theater. Arina and Katya, I present the second certificate of honorary whys. Many thanks to Tatyana for the active support of the rubric. If you have any questions, please write them to the mail, or in the comments.
If you liked it, tell your friends about the Biology Magic blog. This is the best thank you for me. Let there be more people who are not indifferent to wildlife.
