Sometimes The leaves of the plant wither. What could be causing this? Perhaps your watering is not adjusted. Either the plant suffers from lack of moisture, or there is too much water. First, check the soil in the pot to determine the exact cause.
If the soil is dry to the touch and the earthen lump has shrunk and moved away from the walls of the pot, the pot seems light, then water the plant thoroughly. To soak the earthen lump, you need to water the plant by immersing it in water.
Flower pot immerse two-thirds in a container of water for about 30 minutes, so that the earthen ball is well saturated with water, and at the same time, so that the roots of the plant do not become soaked and suffocate. Watch this plant for a few days: do not place the pot in a bright sunlight and water regularly.
If the leaves are still wilting, the pot may not be retaining water. Look at the bottom of the pot - if there are very large holes there, then it is better to replace such a pot.
Due to excess moisture, root rot can develop very quickly. If the soil in the pot has been damp for a long time, it turns sour, the roots begin to suffocate without access to air, and the leaves wither. We start watering more, and only make things worse for the plants. In this case, you will need to transplant the plant into new soil and treat the roots with phytosporin, foundationazole or other fungicide. In order for the plant to quickly adapt after transplantation and quickly restore the root system, growth stimulants and root formation stimulants can be used.
Because too cold water for watering, cold drafts, fusarium may develop. For some unknown reason, the leaves begin to wither, then the whole plant dries out. Sometimes fungicide treatments can help. If you realize it too late, the plant cannot be restored and will have to be thrown away.
Due to a high dose of fertilizer, or the wrong fertilizer, you can burn the roots, and the leaves will first begin to wither, turn yellow and fly off.
If everything is fine with watering and fertilizing, then perhaps the leaves are withering due to pests. For example, from millipedes, nematodes, scale insects, whiteflies, scale insects. In this case, isolate the diseased plant and carry out several insecticide treatments with a break of a week. To make the treatments more effective, after spraying, place a large plastic bag on the plant for two hours. By doing this, you will not breathe in the evaporation from the drugs, and the plant will have longer contact with the active substance.
To the main diseases deciduous trees This includes root and stem rot, necrotic and cancerous diseases. Most hardwood diseases are caused by fungal pathogens. Less commonly, bacteria and viruses are pathogens. Let's look at the most common diseases of deciduous trees and the main methods of treating them.
Yellow heart rot
Black cancer
Another disease that can affect aspens is black cancer It most often affects trees older than twenty years. In sick plants, the crown begins to dry out, the risk of windbreak increases, and the decorative effect is lost. The disease begins with the formation of brown depressed spots on the trunks. Then they become swollen, and when pressed, a whitish liquid begins to flow out of them. At the same time, grayish-black fruiting bodies develop in the bark. Subsequently, oblong wounds from one and a half to two centimeters long appear in the lower or middle part of the trunk.
Gray spot - uh This fungal disease usually develops in the second half of summer. On the leaves, gray spotting appears in the form of gray spots with a dark border. irregular shape. Over time, dark brown sporulation pads begin to develop on them. The spots can merge and occupy the entire leaf blade. Such diseased leaves begin to fall off prematurely.
Ophstomosis of oak on linden
The disease is caused by the fungus Ophiostoma valachicum C. Georg. et Teod. As it progresses, the leaves turn yellow, the branches suddenly begin to wither and dry out, and dryness may be observed. Under the cover of the bark, wet lesions with the smell of rot develop. Sometimes the bark cracks and cancerous ulcers with raised edges form. Gradually the tree dies. The fungus tolerates winter well in infected trees.
Cytosporosis of linden
The disease is caused by the fungus Cytospora carphosperma Fr. As a rule, it occurs on trees that have been damaged by frost and on weakened plants. In this case, the tree bark begins to gradually dry out and then become covered with small gray-white tubercles. Young trees dry out very quickly. In adult plants, the bark of the skeletal branches peels off, then they dry out and the entire tree dies.
Thyrostromosis
The disease is caused by the fungus Thyrostroma compactum (Sacc). This is one of the most common diseases in young trees. In this disease, the bark of branches becomes covered with dark brown necrotic spots. After this, the bark dies and the branches dry out. Subsequently, the tree crown thins out. Flattened black warts are clearly visible on the bark.
Oak brown spot, oak powdery mildew .
The disease is caused by a fungus - Microsphaera alphitoides Griff. et Vaubl. It is characterized by the appearance of a dense white coating on the leaves. Gradually, the plaque darkens, and the leaves themselves dry out and acquire a brownish-brown color. Young leaves and shoots are especially often affected. This mushroom is frost-resistant.
Oak trunk rot
The number of tinder fungi that cause oak stem rot is very large. Any mechanical damage or frost damage promotes the proliferation of these fungi. Large, leathery fruiting bodies appear on the bark of trees. The affected wood has a different color depending on what type of tinder fungus the tree is infected with. Most often, this disease leads to drying out of the entire plant.
Maple powdery mildew
The disease is caused by a fungus - Uncinula aceris Sacc. Its characteristic feature is the appearance of a white cobwebby coating on the maple leaves. The leaves begin to acquire brownish-brown shades and gradually dry out. The tree's winter hardiness decreases, leaves fall prematurely, and shoots do not ripen.
Marginal necrosis of maple leaves
The disease is caused by a number of unfavorable factors. This may be a lack of moisture, especially in young maples; an insufficient amount nutrients in the soil; a large percentage of gas contamination, pollution environment; Central trunk rot caused by tinder fungi.
Stage cancer of maple.
The disease is caused by the fungus Nectria ditissima Tul., and Cylindrocarpon willkommii (Lind) Wr. With this disease, the maple bark begins to turn brown, then gradually dries out. In some places, pockets of exposed wood appear with an influx around the ulcer, which can increase in length more than a meter and go deeper. Pads of a whitish-cream color appear, gradually the wood of the maples dies and the tree dries out. Young maples die especially quickly.
Birch Cytosporosis
The disease is caused by a fungus - Cytospora horrida Sacc. Many dark gray tubercles appear on the bark of diseased trees. Gradually, the bark dies off, the branches dry out, and then the whole tree.
Nectria necrosis of birch bark
This disease is caused by a fungus - Nectria cinnabarina Fr. (Tode) Wint. It is characterized by the appearance on the bark of many spherical warts of orange-red color with a diameter of up to 2 mm. Gradually, the bark begins to die off, individual branches dry out, which leads to the death of the plant.
Birch trunk overflow or burl
The disease is characterized by the appearance of a spherical influx on the tree trunk. It occurs due to damage to plant tissue and has a rough surface. This disease is not infectious. Such influxes do not pose a danger to the life of the plant.
Mixed yellow-brown trunk rot, or birch tinder fungus
The disease is caused by a fungus - Piptoporus betulinus (Bull.) Karst. The first signs of damage to a tree by stem rot include dry sides of the trunks, as well as water shoots and hollows. Fruiting bodies appear on the trunk in the form of yellow-gray caps. The wood turns yellow-brown and becomes brittle. Rot can spread along the trunk to great heights. Gradually the infected tree dries out.
Graphiosis (Dutch disease)
One of the most dangerous elm diseases is Dutch elm disease (graphiosis). This vascular disease is caused by the fungus Ceratocystis ulmi (Buism). Mor.
Most often, above-ground organs are affected, but often the disease spreads to the roots. The fungus, starting to develop in the cambium layer, clogs the conducting vessels, as a result of which the tree dries out. The disease can occur in an acute form, in which case the tree can die within a year, or in a chronic form, in which case the disease lasts for several years. The main spreaders of Dutch disease are elm sapwood, elm bark beetle, gypsy moth caterpillars and Asian longhorned beetle.
There is another, not fully understood, disease of elms, which is characterized by drying out of its branches and wilting of the leaves. The disease is accompanied by the rapid death of branches, first the youngest, then the oldest. On dying branches, the leaves quickly wither and curl, but do not lose their green color. On cross sections of diseased shoots, areas of browned wood are observed. Some scientists believe that the cause of this disease is unfavorable climatic conditions, others suggest that this bacterial disease is caused by Micrococcus Ulmi Bruss, and still others believe that the cause of the disease is the Graphium fungus.
For prevention diseases almost all major deciduous trees recommended annually, preferably spring time spray plants with Bordeaux mixture, uproot and burn diseased trees and remove dry branches. It is also recommended to collect and destroy fall foliage. At the first signs of disease, spray the trees with appropriate preparations. If damage is detected on the bark, it must be cleaned and treated with a 5% solution of copper sulfate, and then covered with oil paint.
Each Living being, be it a plant or a pet, enters into an invisible connection with its inhabitants. Therefore, some of the flowers are not recommended to be kept in residential premises. Many of the window sill residents have medicinal properties. Indoor abutilone is designed to bring calm and peace to your home. Contemplation beautiful leaves and large flowers relieves stress. Where indoor maple grows, conflicts arise less often.
Nothing to do with maple wood indoor abutilone does not have. It was nicknamed maple for its similar shaped leaves. In fact, it is a malvaceae; its closest relative is the hollyhock, known to everyone. Coming from tropical countries, it is demanding on ambient temperature and lighting.
They love the plant for its long-lasting and abundant flowering. Even in unfavorable conditions, indoor maple blooms, but less. Regular flowering from April to November can become year-round if favorable conditions are created.
The plant responds well to garden or balcony maintenance in the warm season. At the same time, its stems become stronger, its leaves become coarser, and it is less populated by pests. One of the most important conditions The decorative effect of indoor abutilon is the formation of a bush by strong pruning.
The plant loves diffused light, as under the canopy of trees, but tolerates direct sunlight for no more than 2 hours a day. It doesn't have to be scorching midday light.
For planting you need fertile, light soil. It can be composed of equal parts:
You need to add crushed coal to the soil. You can take ready-made soil for seedlings of garden crops, but add perlite, sand, vermiculite and charcoal. Drainage is made of expanded clay, pebbles or crushed pine bark. The pot must match the size of the root system.
The air temperature in summer is up to 25 0, in winter the maximum is 15, but it is dangerous to keep at this temperature for a long time, root rot will appear. An air humidity of 60% is quite sufficient, but the plant creates the necessary microclimate around itself independently, without spraying. Watering indoor abutilon should be systematic. The lump of earth is always kept moist, without stagnation of water.
It should be noted that watering is carried out with soft water without residual chlorine; sometimes it is advisable to acidify it in order to maintain the soil pH below 7 units. Fertilizers are applied twice a month after heavy watering, only during the growing season. In winter, if the plant has gone dormant, only monitor the lump of earth, which should be moderately moist.
The plant loves showers and wiping the leaves with a damp cloth. It does not react at all to spraying; in summer, due to water droplets focused on the leaves, it can get burned.
The plant does not like frequent transplants and drafts. Indoor abutilon is sensitive to changing place of residence. At the same time, he gratefully accepts proper care and pleases with its rapid growth and flowering.
A beautiful flower attracts the attention of others. Only an experienced gardener can notice the first subtle signs that the plant is uncomfortable. Then an attentive owner will instantly find the cause and try to eliminate it. But every action, even a quick one, will produce results in 2 weeks. Therefore, when caring for a plant, you need to be patient. It would be good to keep a diary of fertilizing, inspections and treatments.
Clear signs of disaster will be:
All these troubles can arise for two reasons - the conditions of detention have changed and become unacceptable, the plant has been colonized by insect pests.
Most common cause there is a change in the color of the leaves. Let's look at the reasons in more detail. The leaf is green due to the formation of chlorophyll through photosynthesis. There are many complex components involved in the process. If abutilon leaves turn pale and yellow ,
the root cause may be lack of lighting. It is necessary to move the plant into the light, but gradually accustom it to the change, shading it at first. At the same time, it should be taken into account that direct sunlight can promote fading and remove the variegation of leaves.
The same sign of pallor of the leaves will be, which, settling on a tender leaf from below, very quickly multiplies in a cradle of barely visible cobwebs and sucks the juices from the plant. If you don't fight, the abutilon will lose its leaves. Insecticide Fitoverm with treatment once a week is the most suitable enzyme preparation in room conditions. Three treatments in a row, then monitoring the condition.
Drying leaf tips indicate a lack of moisture; you need to increase watering. Perhaps the air in the room is too dry, then you need to throw a damp cloth over the radiator, which will lower the temperature and increase the humidity.
With a draft and a sharp drop in temperature, abutilon inevitably loses its leaves. But this will also happen when the earth clod dries out or the plant floods. The roots should not bathe in stagnant water. Therefore, after watering, the water from the pan is drained an hour later. If in the light the leaves of abutilon curl up and turn yellow, the plant requires shading.
A signal of trouble with the root system will be drooping leaves in wet soil when the temperature has not changed. Yellowing of leaves and leaf fall indicate the time of root revision. However, if in winter time abutilon leaves turn yellow and fall off, branches are exposed, perhaps it is time for dormancy, it depends on the variety. A dormant bush is not fed or pruned until spring. 
As a rule, plants that are weakened or are under intensive care are poorly watered, not fertilized, or given a half dose of fertilizing. Removing from the pot and inspecting the roots is done last. The procedure is painful for the plant.
Yellowing of abutilon foliage is associated with many factors. One of them is lack of nutrition. The pattern on the leaves will tell you about the element that the plant lacks:
An indicator of iron deficiency will be the young upper leaves, in which the veins are green and the yellowness is spreading. If you do not help the plant, the next leaves will come out very pale. It is best to apply foliar fertilizing with Ferrovit.
Magnesium deficiency is indicated by scorched edges or chlorosis of older lower leaves. Magnesium is redistributed in the plant in favor of young leaves and buds. If you do not feed the plant with soluble magnesium salt, the leaves turn up and become curly, the edges dry out. Magnesium sulfate must be present in feeding mixtures.
Starvation caused by a lack of nitrogen fertilizer and sulfur look almost the same. General yellowing and shredding of leaves, weak growth of the bush or its absence indicates a lack of nutrition, especially since it indoor plant loves natural extracts from organic fertilizers.
To the question: abutilone does not grow, what should I do? – the answer lies in a complete analysis of the situation. If the root system is healthy, the lump of earth is sufficient for the development of the plant and the time of rest has not come, then it is necessary to feed the plant.
However, in each specific case, advice is required experienced florist, especially if the abutilon sheds buds, leaves and stands bare. It’s a good idea to know its variety when purchasing a flower, then you can read about its biological characteristics in reference literature.
Japanese maples are deciduous shrubs and trees that grace gardens, patios, decks and flower beds around the world. Red foliage looks attractive; the decorative appearance of plants with purple, orange, and maroon crowns is appreciated by professionals landscape design and amateur gardeners. (red) is a challenge to the author of the tired phrase “green spaces”. The unusual coloring of the graceful leaves appeared as a result of natural processes and the painstaking work of breeders.
The Japanese maple acquired its spectacular appearance thanks to its complex biochemical composition. From school, many people know about chlorophyll, which gives leaves green color. In addition to this pigment, plants contain carotenoids, their presence causes red, yellow and orange colors. Purple, brown, orange and foliage are due to the accumulation of anthocyanins in the cell sap. The beautifully shaped leaf blades can be painted in purple and carmine tones, in harmony with the gray tint of the bark. The crown of trees is usually round, found in the shape of an oval or a mushroom cap. The dissected leaves of red maples look like lace from a distance. Inflorescences, fruits, even bark patterns - the entire above-ground part looks very decorative. In autumn, the leaves acquire brighter shades and fall off in the winter. But the plant continues to delight the eye with the grace of its thin branches and unusual crown.
The plant belongs to the Sapindaceae family (lat. Sapindaceae), belongs to the Maple genus. Homeland - forests of Southeast Asia. The variety of small forms of Japanese maples is surprising; they have been created in the Land of the Rising Sun for centuries. Now in many countries, breeders are developing new cultivars of the popular ornamental plant. Varieties of maples belonging to three types look bright and elegant:
In summer, the golden foliage of the Shirasawa maple attracts attention in gardens and terraces; in autumn it turns bright orange. Dutch fan maple varieties are covered in glossy dark red leaves in the spring that change color to orange-red before falling. The openwork crown acquires bright shades in good sunlight or partial shade.
Compact in size, Red Fan Maple displays rich shades of purple, orange and pink. The homeland of this species is the forests of Japan, Eastern China and Korea. IN natural conditions trees reach a height of 8-10 m. The crown becomes round or mushroom-shaped with age. Young shoots of the plant are covered with colored skin. In spring, the leaves turn red; in the summer of some cultivars they turn green, and in the fall they turn purple. The flowers are collected in bright loose inflorescences. The shape of lionfish varies greatly among different varieties fan maple. The plant is heat-loving, demanding on soil fertility and moisture, but does not tolerate excess water. Temperatures below -15 °C lead to damage to the root system. The species is propagated by seeds, which can be sown immediately after collection. Common forms of palmate maple: pink-bordered, crimson, purple dissected and others.
Trees with red leaves look good alone in groups. When planting, the distance between plants should be left 1.5-3.5 m. For seedlings, prepare a planting hole 50-70 cm deep. In a wetland, you need to take care of good drainage (sand, crushed stone, construction waste). Red maple seedlings are placed in a hole with a loose layer at the bottom. Fill the planting hole halfway with water and cover it with substrate, which is mixed with full mineral fertilizer. There are new varieties that do not exceed 1.5 m in height and can grow in containers. Pots for planting should be ceramic or plastic Japanese style. Red maple prefers loose, humus-rich substrates and does not like waterlogging. Soil for containers is mixed with compost in a 1:1 ratio or prepared from equal parts of turf soil and peat, sand is added.
Red maples do not require radical pruning, but be sure to remove diseased and dead branches. In spring, care consists of replacing the top layer of compost with fresh compost, pre-enriched with fertilizers. The mixture is prepared from 40 g of urea, 30 g of superphosphate and 25 g of potassium salt. can be covered with mulch to retain moisture and protect against crusting. Watering in summer must be combined with fertilizing and loosening. Red maple tolerates lack of moisture, but loses its decorative properties. The watering regime must be adjusted depending on the climate of the area and weather conditions. Winter hardiness largely depends on the type, variety and age of plants. In autumn, the roots of young trees and bushes on the site should be insulated with dry leaves, and the containers should be brought indoors.
In autumn, cuttings (20 cm) are cut for vegetative propagation. They are dug in in the winter and rooted in containers or pots in the spring. Filling containers light soil, must be mixed with sand. In the spring, buds or cuttings of ornamental cultivars are grafted onto more winter-hardy and fast-growing varieties of the same species (or closely related ones). For seed propagation, lionfish are collected and sown in the soil in the fall. But it is better to create conditions for them that resemble stratification in nature, which occurs in winter at a temperature of about 3 °C. In the spring, the seeds are soaked before sowing, and when they hatch, they are sown in the garden to a depth of 4 cm. In the hot summer, the seedlings need to be shaded. Seedlings that have reached 50-80 cm can be transplanted to a permanent location.
Red maple is a hardy plant, but vulnerable to direct sun rays, drafts. Trees and bushes affected by unfavorable conditions may shed their leaves prematurely. Branches and roots are damaged by frost if the temperature drops below -15 ° C. Maples do not like open areas facing south. Ideal place for them - protected from the wind, with mosaic lighting. All cultivars are suitable for Asian-style gardens, patio landscaping and front gardens. The umbrella-shaped crown creates shade in seating corners and on garden paths, contrasts with the bright greenery of the evergreen hedge, plants typical of middle zone. Original shrubs and trees can be used in rocky gardens; they harmonize with dark coniferous species. Fast-growing varieties of palm and fan maples reach a height of 4-5 m. Perennial flowers that do not require good lighting can be planted under the crown of these red trees.
This group of diseases is most common on maple. Powdery mildew and spotting predominate; other types of diseases (deformation, blackhead, mosaic) are less common.
Depending on the biological characteristics of the pathogens, diseases appear during different periods of the growing season. This largely determines the degree of their harmfulness. Leaf diseases are most dangerous for young plants in nurseries.
With severe damage, mycelial plaques and spots completely cover the surface of the leaf blades. This leads to disruption of physiological processes, premature drying and falling of leaves. With repeated lesions, the decorative value of trees and their resistance to unfavorable environmental conditions are reduced.
Sources of infection in nurseries are fallen, diseased leaves, on which pathogens persist in the form of overwintering stages. In spring, sporulation forms on overwintered leaves and primary infection of the leaves occurs.
The causative agents are the fungi Erysiphe (=Uncinula bicornis) and E. tulasnei (=U. tulasnei). At the end of May - beginning of June, it appears on both sides of the leaves. white coating mycelium with conidial sporulation. Very quickly, the coating completely covers the entire surface of the leaf blades, giving them the appearance of being sprinkled with flour. Dry sunny weather promotes intensive formation and rapid spread of conidia.
In summer, several generations of conidia are formed, so massive repeated infections of leaves occur every 10–14 days. Conidia spread through the air to long distances, up to 100 m or more.
In the second half of summer, the fruiting bodies of the marsupial stage of pathogens - cleistothecia - are formed on the mycelium. They look like numerous small, initially yellowish, and later black, scattered or collected in groups of dots.
Cleistothecia overwinter on fallen, infected leaves or on the soil. In the spring of next year, ascospores ripen in them, causing primary infection of the leaves.
The causative agent is the fungus Septoria acerella. In the second half of summer, small round or angular white spots appear on the upper side of the leaves. In the center of the spots, conidial sporulation of the pathogen is formed - pycnidia, which look like small black dots located in close groups.
Are affected different types maple, mainly field maple (Acer campestre).
The causative agent is the fungus Mycocentrospora acerina (=Cercospora acerina). In the first half of summer, numerous small brown, dark brown or dark red spots appear on both sides of the leaves, often covering the entire surface of the leaf blades. Conidial sporulation of the fungus in the form of olive-colored tufts is formed not only on the spots, but also near them.
Different types of maple are affected, but more often - Norway maple (A. platanoides), false sycamore, or white sycamore (A. pseudoplatanus), field.
The causative agent is the fungus Phyllosticta minima (=Ph. acericola). In the second half of summer, round, red-brown spots with a dark border, up to 10 mm in diameter, appear on the upper side of the leaves. On the spots, conidial sporulation of the fungus is formed - pycnidia, which look like small black dots located around the circumference of the light part.
Different types of maple are affected, but more often - field, Tatarian, or black maple (A. tataricum), sugar maple (A. saccharum).
The causative agent is the fungus Phyllosticta platanoides. In the second half of summer, large pinkish spots with a vague dark brown border appear on both sides of the leaves. On the lower side of the spots, conidial sporulation is formed - pycnidia, visible in the form of a continuous layer of small black dots.
The causative agent is the fungus Rhytisma acerinum. In the first half of summer, large round yellowish spots appear on the leaves. Later, dense fungal tissue - stroma - develops on them. In this case, the spots become black, convex, shiny, 1–1.5 cm in diameter, with a yellow rim.
Initially, conidial sporulation develops in the stroma, causing infection of leaves in the summer. In autumn, fruiting bodies - apothecia - form in the stroma, overwintering on fallen leaves. In the spring of the following year, ascospores formed in apothecia produce primary infection of the leaves.
Different types of maple are affected.
The causative agent is the fungus Taphrina polyspora. In June, numerous angular brown or dark brown, almost black spots appear on both sides of the leaves, which later swell and wrinkle. On the upper side of the spots, marsupial sporulation of the fungus develops in the form yellow plaque. Numerous spots merge and cover almost the entire surface of the leaf blades. As a result, the affected leaves become severely deformed, turn black, dry out and fall off.
The ginnala maple is affected.
The causative agent is the fungus Fumago vagans. In summer, often in dry and hot weather on the upper side of the leaves a black, sooty, superficial, easily abraded or washed off coating of mycelium with conidial sporulation appears. With severe damage, the leaves are completely covered with plaque and acquire a characteristic dirty black color.
The causative agent is a saprotroph and feeds on the sugary secretions of aphids, coccids, psyllids and other sucking insects that live on the lower surface of leaves. At the same time, their secretions flow onto the leaves located below.
Pathogens: Arabic mosaic virus and Tomato black ring virus. Various types of maple are affected, including Norway maple, Ginnala, or river maple (A. ginnala). The disease manifests itself in uneven coloration of leaves, on which dark, light and yellowish-green spots appear. Often the leaf veins are shortened, the leaves are deformed, become wrinkled and curled.
Mosaic vectors are sucking insects, including aphids and whiteflies.
Of the diseases of this group in nurseries, the most common and dangerous are vascular wilt (wilt) and necrosis, which cause weakening and death of the maple tree in a relatively short period.
Sources of infection are diseased plants and cut affected branches, and the wilt pathogen can survive on plant debris in the soil.
Wilt and necrosis diseases, as a rule, affect plants weakened by the influence of unfavorable environmental factors (weather conditions, insect damage, industrial pollution, violation of plant care technology, etc.).
The causative agent is the fungus Verticillium dhaliae. The mycelium of the fungus develops in the vessels of trunks and branches and clogs them, preventing the flow of water and nutrients. External signs of wilt appear in the drying out of individual branches or the entire crown. At the same time, water shoots appear on the trunks, which also dry out. In some cases, the number and size of leaves in diseased trees decreases, and the crown becomes lacy.
A characteristic symptom of the disease is a change in the color of the wood, clearly visible on cross sections of trunks and branches. Affected wood becomes light greenish, greenish-black or olive color. In this case, stripes or streaks with a changed color initially appear, later turning into a solid color.
In the affected tissues, chlamydospores and their accumulations - microsclerotia - are formed on the mycelium, which can retain the ability to infect for several years. The spores infect trees through damage to trunks in the root collar area.
Several variants of the course of the disease are possible. In some cases, drying out begins with individual branches, gradually covering the entire crown, in others the tree is without external signs the lesions do not bloom in the spring, or suddenly dry out in the middle of summer. Very rarely the disease becomes chronic and sometimes ends with the tree recovering.
In all cases, the fungus causes partial or complete death of the roots. Dried trees can be easily pulled out of the ground.
Warm and humid weather promotes the development of the disease. Sources of infection are logging residues (infected bark and wood) and soil in which the pathogen persists in the form of microsclerotia and chlamydospores.
Various types of maple and some agricultural crops are affected, including beets, potatoes, and sunflowers.
The causative agent is the fungus Tubercularia vulgaris. Various types of maple are affected, but most often - Norway maple and false sycamore.
The fungus develops in the bark and often in the vessels of trunks and branches. In the latter case, in diseased trees, the leaves first wither, and later the branches die. In this case, the peripheral parts of the wood of the trunks and branches acquire a greenish color.
In the thickness of the affected bark, conidial sporulation of the pathogen is formed - round, reddish or bright pink smooth pads with a diameter of 0.5–2 mm and a height of up to 1.5 mm, which later become granular, brick-red or Brown. Sporulation often completely covers the affected trunks and branches, giving them a pink color.
The spores of the pathogen are spread by rainwater and insects. Conidia are formed throughout the year, but their germination and infection of trees is possible only during the growing season. Very rarely, the fungus develops a marsupial stage - Nectria cinnabarina, the spores of which also infect plants.
The causative agents are fungi from the genus (Cytospora). Different types of maple are affected.
Initially, local necrotic areas appear on the bark of trunks and branches, which develop and quickly ring thin trunks and branches. In thicker trunks and branches, wounds form at the site of necrosis within 2–3 years.
The affected bark may be darker or lighter than healthy bark; often its color does not change. In the thickness of the affected cortex, conidial sporulation of pathogens develops - numerous small dark conical tubercles (pycnidia), protruding from breaks in the periderm with white or grayish-white disc-shaped peaks.
In the spring, mature spores emerge from the pycnidia, solidifying in air in the form of drops, strands and spirals of red or orange color. Conidia are spread by rainwater and insects.
The causative agent is the fungus Diplodia atrata. Different types of maple are affected.
The color of the affected bark of trunks and branches remains almost unchanged. In the thickness of the bark of necrotic areas, conidial sporulation of the fungus - pycnidia - is formed. They look like numerous black tubercles protruding from transverse cracks in the bark. At the same time, the surface of the affected areas differs sharply from healthy ones; it is rough and black. Conidia are spread by rainwater, insects, and less commonly by air.
In the system of measures to combat maple diseases great importance has supervision over the emergence and spread of diseases. Surveillance is carried out during the period when the characteristic symptoms of diseases are most clearly manifested - from the moment of complete foliation until the end of summer. Such observations allow timely planning and implementation of protective measures.
To grow maple, it is necessary to choose areas that have not previously been occupied by beets, potatoes and sunflowers, since the soils under these crops can be a potential source of wilt.
It is very important to create optimal conditions for the growth and development of maple, which increase the plants’ resistance to wilt and necrosis diseases. Limiting the spread and development of necrotic diseases is greatly facilitated by pruning, removal and destruction of affected branches.
Trees infected with wilt must be removed, always with roots on which the pathogen can persist for several years.
To reduce the spread powdery mildew and spotting, it is necessary to destroy fallen leaves on which pathogens remain in the form of mycelium or fruiting bodies. In the fight against powdery mildew and leaf spots, the chemical method is quite effective, but its use is advisable only when these diseases are widespread.
During the growing season, the crowns are sprayed 2–3 times with protective fungicides that prevent the germination of pathogen spores and infection of leaves. Treatments should begin when the first signs of disease appear on the leaves (white powdery coating, spots of various shapes, colors, sizes). Repeated spraying, depending on weather conditions, is carried out at intervals of 1–2 weeks.
To destroy the wintering stages of powdery mildew and spot pathogens and reduce the level of primary maple infection, late autumn or spring spraying of fallen leaves with eradicating fungicides is carried out. Processing times and drug consumption rates should be strictly observed.
