Changes in the color of apple and pear leaves occur for a number of reasons. Most often, the tree lacks nitrogen, other macroelements, moisture or light. Sometimes the plant is damaged root system or the disease develops. How to deal with yellowing leaves?

Often leaves fruit trees turn yellow throughout the summer. At first they become covered with small spots, wrinkle, and then fade and completely fall off. There may be several reasons for the color change:

lack of macronutrients and nutrients,
bacterial infections,
temperature changes,
activity of diseases and pests.

Let's consider each of possible problems separately and tell you about ways to eliminate it.

What causes leaves on apple and pear trees to turn yellow in June?

IN recent years apple and pear leaves begin to acquire “autumn” colors at the very beginning of summer. This may be due to one of the following reasons.

Heat. If you did not water the plant with enough water, it could disrupt the nutrition of the roots and foliage. Therefore, urgently increase the intensity of watering to at least once every three days.
Excess moisture. However, you should be careful with watering - if there is excess moisture, the root system becomes flooded (most often this happens on heavy soils). clay soil). In this case, the tree should be watered no more than once a week.
Sunburn. If you watered an apple or pear tree abundantly on a hot day and some of the water got on the leaves, this could lead to burns and yellowing. In this case, you can feed the tree with mullein infusion (dilute 1 cup of fertilizer in 10 liters of water) or spray the foliage with Zircon after sunset so as not to burn the leaves again.
Herbicide ingress. If you carried out massive pest and disease control in the spring, then some of the pesticides probably got on the leaves and caused them to die prematurely.
Moles. These small animals could dig under and damage part of the root system. If you see earthen mounds in your area, it means it’s time to get rid of the moles.

Spray herbicides carefully, as some of the substances fall on the leaves of fruit trees

Why do leaves turn yellow on young apple and pear trees?

It is especially disappointing to watch the leaves of young trees, which should delight you with fresh greenery and bright flowers, turn yellow. There may be several reasons for the “autumn mood” of apple and pear trees.

Deepening the roots. Perhaps, when planting, you planted the seedlings too deeply, and the root collar ended up 10-15 cm below the ground level. Such planting gradually weakens the tree, it develops poorly and bears little fruit. In this case, it is easier to uproot it and plant a new apple or pear tree.
Close location groundwater . Prolonged waterlogging also leads to oppression of the tree and the fact that the root system stops “breathing.” A so-called “gley horizon” is formed, in which iron and manganese compounds accumulate, which are toxic to most plants. You can try to transplant a tree with a large lump of earth to a new location.
Sulfur and iron deficiency. If not only the apple or pear tree turns yellow, but also other nearby plants, they may lack sulfur or iron. A deficiency of these microelements is observed with excessive application of ash or lime. Neutralize their effect with ammonium sulfate or nitrate.
Scab develops. If this disease occurs, the tree should be treated with Skor or Fitosporin 3-4 times per season in accordance with the instructions. After watering (3-4 buckets of water), feed the tree with nitroammophos (one matchbox per 10 liters of water) at the rate of 2-3 liters of solution per plant.

With magnesium deficiency, the edges of the leaves become dark purple in color.

Why do apple and pear leaves turn yellow and fall off?

Often the leaves not only turn yellow, but also fall off after some time, depriving the tree of food. Diseases and pests are usually to blame for this.

Chlorosis of apple and pear trees. This disease is caused by prolonged drought, flooding of the site, leaching of organic and mineral substances from the soil and its depletion. First of all, “nitrogen nutrition” should be strengthened. For example, feed the tree with ammonium sulfate or urea (35 g per 10 liters of water, apply 3-4 liters of the composition under the bush) . Azotobacterin is also used (2-3 bottles of the drug for one tree). Sometimes Antichlorosin (100-120 g per 10 liters of water) is used to treat the roots, or, if the pear is sick, they are sprayed on the leaves and shoots.
Tick attack. Browning and falling leaves can be caused by small mites (brown and red fruit mites). They feed on the sap of young leaves and are resistant to most pest control drugs. It is recommended to spray trees with acaricides (Neoron) and insectoacaricides (Karbofos, Karate).

With severe development of chlorosis, the root system dies

Why do the leaves of apple and pear trees turn yellow and dry out?

Sometimes during the summer the leaves of apple and pear trees turn pale and dry out, and then dot the ground with a continuous “dry carpet.” And this is not a sign of imminent autumn, but a consequence of one of the the following reasons.

Moniliosis. This disease is manifested not only by yellowing of leaves. As it develops, the entire tree looks as if it has been scorched by fire - twigs and other parts become dry and lifeless. Moniliosis usually appears 2-3 weeks after flowering, and its peak occurs in August. After flowering, the plant should be treated with any antifungal drug, a 1% solution of Bordeaux mixture or copper oxychloride (30-40 g per 10 liters of water).
Bad rootstock. Due to the incompatibility of grafted plants, moisture and nutrients do not reach the tree branches. In this case, practically nothing can be done; one can only hope that next time the vaccination procedure will be more successful.

With moniliosis, the leaves quickly change color from yellow to dark brown and soon die

What causes leaves on apple and pear trees to turn yellow and curl?

Apple and pear leaves are susceptible to many diseases and negative external factors. Therefore, if they begin to turn yellow and then curl, it means that the following problems may be the cause.

Lack of calcium. Young leaves lighten and curl upward, growing points die off, and the leaves soon fall off. If symptoms of calcium deficiency appear, you should check the acidity level of the soil and lime it if the pH level is exceeded (the normal level for most fruit trees is 6-7 pH). At normal level pH trees are fed with calcium sulfate.
Frostbreakers. When the root system freezes, oppression begins not only of it, but also of the trunk, branches, shoots, and leaves. The latter become small, turn yellow and curl. In this case, watering the trees with a solution of urea (500 g per 10 liters of water), as well as a mixture of mullein and clay, which is used to cover the wounds formed on the trunks under the influence of low temperatures, will help.

When frost damage occurs, the foliage may turn yellow closer to mid-summer and rapidly fall off.

Causes of yellowing leaves on seedlings

Even seemingly healthy seedlings can suddenly turn yellow. This may be due to low quality planting material or be caused by one of the following reasons, which appear after landing.

Nitrogen deficiency. In the early stages of growth and development, young trees suffer most acutely from nitrogen deficiency. Be sure to add humus (4-5 kg per 1 sq.m of tree trunk circle) and seal it to a depth of 35-40 cm.
Critical temperature changes. If you planted an apple or pear tree too early, or frosts occurred in winter after a thaw, young tree may freeze. To prevent this from happening, in the fall the trunk should be tied with insulating material - pine spruce branches, burlap, fabric.
Barrel damage. At the base, at the border of the trunk and the root system, the tree could be damaged by mice and other rodents. In this case, covering the wounds with thick clay mash (the damaged areas are cleaned down to healthy tissue, coated with clay mash and wrapped in cotton cloth) or grafting with a bridge can help. It is better to refuse to plant a partially damaged seedling, since the tree will still be sick and bear little fruit.

Sometimes the leaves are yellow right on the seedlings - it’s better not to buy such specimens

How to treat trees with yellowing leaves

A universal treatment for trees with yellowing leaves is Bordeaux mixture. To prepare it you need to mix 100 g copper sulfate, 100 g of lime and 10 liters of water. It should be sprayed once every 2 weeks.

Spraying the solution also helps. calcium chloride(25-30 g per 10 liters of water). If the leaves gradually become gray, and their edges turn brown, this indicates iron deficiency. In this case, use a solution iron sulfate(60-80 g per 10 liters of water). During bud break, budding, during the flowering period, as well as in July-August, a solution is used to control pests colloidal sulfur(100 g per 10 liters of water).

Now you know everything about the reasons for yellowing of leaves on apple and pear trees. Only your timely and quick actions, as well as correctly selected drugs and solutions, will help prevent serious diseases and save your suddenly yellowed trees.

Line UMK V.V. Pasechnik. Biology (5-9)

Biology

The world around us

Why do the leaves on trees turn yellow and fall off in the fall?

With the arrival of autumn appearance trees are changing. The dense green crowns are replaced by bright crimson-red “caps” of leaves, which then completely fall off. Why do green leaves change color and why do trees shed their leaves every year? Let's understand the details of tree life from a scientific point of view.

Leaves the color of summer

A special substance is responsible for the emerald foliage of any plant chlorophyll- a pigment that gives leaves a green color. It not only provides fresh herbal color, but also nourishes plants by participating in the formation of glucose and other nutrients.

This pigment is produced through the process of photosynthesis. Leaves absorb carbon and release oxygen. This happens in comfortable conditions- in the presence of heat and sun. In addition to oxygen, photosynthesis also produces the chlorophyll we know.

With the onset of the cold season, sunny days become shorter: the weather is no longer pleasant with warmth, and there is less light. Chlorophyll ceases to be actively produced and is replaced by other pigments.

Every Hunter Wants to Know

The autumn colors of the foliage are due to special pigment substances. Carotene is responsible for orange. This pigment can be found not only on the autumn crowns of trees, but also in ordinary carrots. Yellow leaves appear due to xanthophyll, and red leaves due to anthocyanin.

The conditions for the production of pigments are different. If chlorophyll needs a lot of heat and sun, then xanthophyll and carotene need enough heat and a little light. But to get a lot of purple leaves, you need cold weather and bright sun. Frost and plenty of light are the conditions for the appearance large quantity anthocyanin in foliage.

Proposed notebook - part educational complex to the textbook by A. A. Pleshakov, N. I. Sonin “Biology. Introduction to biology. 5th grade." Special signs mark tasks aimed at developing meta-subject skills (planning activities, identifying various features, comparing, classifying, establishing cause-and-effect relationships, converting information, etc.) and personal qualities students. The material in the notebook is arranged in the same sequence as in the textbook.

Yellow leaves swirl over the city

In autumn, trees at first delight us with bright colors, but as we get closer winter time They are starting to shed their leaves. Why and why does this happen?

With the arrival of the cold season, the soil begins to freeze. Trees stop receiving the required amount of moisture and nutrients. Life processes begin to stop, plants go into hibernation. In order not to waste energy on nutrition, plants are forced to get rid of excess load - and shed their leaves.

At the base of the petiole (the narrow part of the leaf, the place where the leaf blade is attached to the stem), a special separating cork layer is formed, blocking the “delivery” of nutrients from the tree. It becomes increasingly difficult for weakened leaves to stay on the branches and gradually they begin to fall off. As with the appearance of a multi-colored crown, so with the fall of leaves, all processes do not occur instantly. That is why at first we see a measured change in the colors of the foliage, and then the trees slowly get rid of their bright attire.

Leaf fall is a prerequisite for the existence of trees, helping them renew their foliage annually. With the arrival of spring, the trees again begin to receive required quantity water from the thawed soil and revive their lush crown.

But also among coniferous trees there are exceptions, for example, larch. It grows in harsh conditions and cannot evaporate moisture in winter. Therefore, like deciduous trees, also sheds its needles as winter approaches.

The generous summer has passed, autumn has arrived. Its calendar beginning is September 1, its astronomical beginning is on the day of the equinox, September 23, and in nature it, like spring, comes at different terms. We recommend that you read with your children, why leaves turn yellow and fall from trees in autumn. The information will be useful for both little curious people and adults 😉

Birch trees turn yellow first

The first harbingers of autumn are considered yellow leaves on the birches. The mixed forests of the northern and temperate zones are becoming unrecognizable. The monochromatic green summer color gives way to bright colors. The leaves of hornbeam, maple and birch are now light yellow, oak - brownish-yellow, cherry, rowan, barberry - crimson, aspen - orange, and euonymus - purple.

Each tree is charming on its own, and their combination is fabulously beautiful. Not only trees are painted, but also shrubs and grasses. In the forest, their bright outfit is less conspicuous, but in treeless places, the shaggy, motley carpets delight with their multicolored colors.

Reasons for autumn colors

It is known that the green color of a leaf depends on the green pigment - chlorophyll. But chlorophyll is not the only pigment in leaf cells. In the leaves and yellow, orange pigments- xanthophyll, carotene. By autumn, chlorophyll is destroyed; other pigments previously masked by it appear in all their glory, anthocyanin pigments develop, coloring the leaves in reddish and purple tones.

Leaf fall, leaf fall, yellow leaves are flying...

The wonderful decoration of the trees is short-lived. The leaves begin to fall; This process is absolutely necessary. And here's why. Leaves evaporate moisture, and in winter water does not flow from the roots to the tree crowns. If the leaves had remained on the tree, it would have dried up. In addition, leaves weighed down with snow would bend and break branches, which sometimes happens during early autumn snowfalls. Over the summer, a lot of mineral salts that the plant does not need accumulate in the leaves. When leaves fall, the plant gets rid of them. Finally, fallen leaves provide fertilizer.

But why leaves held on to the branches so tightly trees in summer it's so easy fall in autumn?

Even before the leaves change color, their nutrients move to the branches, trunk, and roots. At the same time, a layer of special thin-walled cells appears at the base of the leaf petiole, a kind of partition between the branch and the leaf petiole. The cells of this layer have smooth walls, and the connection between them is easily broken. At the beginning of leaf fall, the leaf remains on the branches only thanks to vascular bundles. This connection is fragile. It is enough for a heavy dew to fall, a breeze to blow, and the leaf comes off.

After the leaves fall, a deep peace comes to the trees. Different plants have different durations. In poplar, lilac, bird cherry it ends by December, in oak, birch and linden it continues until February. Branches cut from a tree during dormancy usually do not bloom in water.

Autumn is a capricious golden beauty!

Wonderful golden autumn! She is sad and beautiful even in a time of decline. “Sad time, charm of the eyes!”

Here is an autumn meadow. It has become wider, more spacious. Here and there yellow tansy, blue chicory inflorescences, wild pansies. And in October you can collect a modest bouquet.

And how good is the autumn dew! In autumn there are a lot of cobwebs, sometimes they form entire walls between bushes and tall grasses. The web behind the dew drops is not visible, and the drops seem to hang in the air.

Autumn white crispy mornings are amazing. Quiet. Everything is covered with frost, like shiny powdered sugar. Everything in nature breathes freshness, purity, and vigor.

Autumn has its own unique scent. The forest smells of mushrooms, and in the garden, even after harvesting apples, their smell lingers for a long time.

There is so much beauty in the naked forest! Leaves rustle underfoot. They know no peace - they tremble, spin around the ground, and, caught by the wind, rush in its stream.

Late autumn is capricious. It brings bright warm days less and less often. More and more often she quietly cries with small drops of rain. Sometimes silent rain suddenly gives way to a storm. An angry wind stirs up the leaden clouds, tears the last leaves from the trees, bends the grass to the ground. But he's not scary. Trees willingly give up the leaves they do not need, and grasses have long sent out their seeds. Animals are not afraid of cold winds either: they have prepared for winter.

And winter is already conducting reconnaissance. It's time for winter. Suddenly snow falls. Once it covers the earth, twice... Each time it is more abundant. And it stays there longer and longer. Finally the frost stopped the rivers. Autumn is over. Winter has arrived!

Greetings, my dear researchers!

Today on discussion new project, the material on which can be useful to you for your next presentation in the lesson “The World Around You”. Why do leaves turn yellow in autumn? This question is often interesting for children, especially when they are walking along park path, raking fallen leaves with his foot. But really, why?

Lesson plan:

What artist paints leaves?

In the summer, the green canopy of trees lives through a process called photosynthesis. Have you heard of this one?

I think it’s no secret even for preschoolers that leaves absorb carbon and process it using the energy of the sun into organic substances that they feed on, releasing oxygen back. This magic inside a tree leaf occurs only under comfortable conditions: warmth and sunlight are important for it. What is responsible for paints?

How do pigment neighbors live in leaves?

I see the question in my eyes: “Why, if all the pigments live together, are there no yellow and orange leaves in the summer, but no green leaves in the fall?”

The thing is that active chlorophyll, with its large amount in warm time masks other dyes, they are simply not visible. With the onset of autumn, when there is little sun and daylight, the green artist begins to be produced less and less, no longer being replenished in such quantities as in the summer. That's when other shades begin to shine through.

That’s why very often, at the very beginning of autumn, the leaves on the tree are not all colored at once, but are painted in a bizarre pattern, when green veins still remain on the yellow or orange background.

Every day closer to winter, the existing chlorophyll is destroyed, new chlorophyll is not replenished due to the lack of conditions for photosynthesis. The veins of the leaves, through which nutrients flow, are closed with a dense plug of cells, reducing the amount of sap in the plant.

Here it is: golden autumn is in full swing, green leaves can no longer be found on the tree! Moreover, the faster the cold sets in, the sooner the tree “turns off” photosynthesis. A colorful carpet appears under your feet, it’s time to collect a colorful autumn herbarium or make a couple of crafts from autumn gifts.

Why do trees shed leaves?

Yellow leaves are circling over the city,

With a quiet rustling they fall at our feet...

Indeed, they would stand all winter long, delighting us with their bright beauty. But no! Leaves begin to fall at our feet, heralding the change of season. Why?

With the arrival of cold weather, the soil begins to freeze, and the trees no longer have enough moisture and minerals. Life processes gradually fade out, all plants go into hibernation. How can you sleep if every leaf needs to be fed? We have to save on food by getting rid of unnecessary consumers, which is why trees shed their leaves before winter.

At the place where the leaf petiole is attached, a special cork layer is formed, which blocks the flow of nutrients from the tree. The leaves hold on weaker and weaker every day and gradually fall off. As when changing color, they do not all leave the tree at once. Some will linger longer, fluttering in the wind, some will fall among the first, lining golden paths.

Therefore, leaf fall is a condition for the continuation of the life of a tree, necessary so that with the arrival of spring we can once again enjoy young green leaves.

This is how briefly we found the answer to the question posed today. To make the report interesting, I propose a puzzle on an autumn theme. Catch it! And I say goodbye to you until we meet again on projects.

“On a stream, pockmarked and motley,

Poem - “Before the Rain”

Evgenia Klimkovich.

Have you ever wondered why autumn is golden? Why do leaves turn yellow in the first place? Let's try to figure out this issue and tell you.

Pigments are responsible for the color of any plant. For example, the red color of an apple is due to anthocyanin, the green color of a cactus is due to chlorophyll, and the orange color of carrots is due to carotene. The yellow color comes from xanthophyll. Anthocyanin, carotene and xanthophyll are carotenoids. They give color to the leaves.

But how does this happen? Why do they appear in the leaves in the fall? After all, in the summer we see green tree crowns.

It turns out that the whole problem is chlorophyll. The amount of carotenoids does not increase, but chlorophyll decreases. With the onset of cool weather, trees switch to energy saving mode.

In summer, when there is a lot of sun, green leaves filled with chlorophyll absorb light and convert it into something useful for the plant. chemical processes. Photosynthesis occurs. As you can imagine, in the fall the daylight hours become significantly shorter. But the leaves have chlorophyll, and they really want the sun. And there is not enough of it. At such moments, the crown “sits on the neck”, sits on the neck of the tree and begins to draw out all the useful substances from it. Then the tree decides: that’s it, hair, I can’t afford you! I won't give you magnesium. Because of this, the leaves fall off. And the tree trunk calmly survives the cold, and then acquires a crown again.

But before that, due to the reduction in the amount of chlorophyll in them, they will turn yellow. After all, carotenoids will predominate.

By the way, it is interesting that those leaves that have fallen and turned brown no longer contain any pigment at all.

However, why, for example, does the Christmas tree not turn yellow and shed its leaves? In fact, conifers shed needles, but not in such quantities. In addition, it’s all about the peculiarities of the structure of the needles. Each needle is encased in a protective wax sheath. There is also more than enough chlorophyll there. But the area of the needles less area leaves, so the trees survive the cold quite calmly.

Yes, such interesting chemical processes are happening around us. But we don't always notice it.

Did you know about this feature of trees? Tell us in the comments!