Elm Bonsai: Production Methods and Cultivation and Care Knowledge

Growing Techniques Jan 1, 1970 0 views

Elm is distributed throughout China, and is generally transplanted during the dormant period in winter and spring, with the highest survival rate before bud break in February and March. Elm is a deciduous tree of the Ulmaceae family and Ulmus genus, with grayish-white or grayish-brown bark and elliptical to oblong leaves with irregular single serrations along the edges. There are many varieties.

Elm is distributed throughout China, and is generally transplanted during the dormant period in winter and spring, with the highest survival rate before bud break in February and March.

Elm is a deciduous tree of the Ulmaceae family and Ulmus genus, with grayish-white or grayish-brown bark and elliptical to oblong leaves with irregular single serrations along the edges. There are many varieties; those suitable for making bonsai are Chinese elm (Ulmus parvifolia), red elm and other varieties with small, dense leaves and gnarled, twisted roots and trunks.

Elm bonsai can be shaped either during the growing season or during the dormant period, but the bud-break period should be avoided to prevent excessive sap loss that would affect plant growth. The form can be worked into various styles of bonsai based on the basic shape of the stump, such as straight-trunk style, curved-trunk style, slanting-trunk style, withered-trunk style, waterside style, cascade style, and forest style. The canopy can use either the elegant, loosely branched natural style, or the rounded large-tree form, and can also be worked into a neat round-pad shape. The shaping method combines wiring and pruning: first use metal wire to coil out the basic form, then prune carefully.

After elm survives, it is robust in habit and easy to manage. The finished bonsai can be placed in a spot with ample light and good ventilation for care, keeping the pot soil moist but not waterlogged. In summer when the air is dry, spray a little water on the plant to increase air humidity and keep the leaves fresh in color. Apply a decomposed, dilute liquid fertilizer about once every 20 days. Elm bonsai has strong sprouting ability and grows quickly, so it must be pruned often, both to maintain the beauty of the tree shape and to increase the plant's light penetration. The best viewing period for elm bonsai is when new leaves have just grown out. If all the old leaves are removed in early to mid-August and water and fertilizer management is then strengthened, by mid-to-late September new leaves as tender green as spring will grow again, greatly enhancing the ornamental value. In winter, the whole pot can be buried outdoors in a wind-sheltered, sunny spot, or moved to a cold room to overwinter; the temperature should not be too high, otherwise the plant will not get sufficient dormancy, affecting the next year's growth. Repot once every 1 to 2 years in early spring, using sandy soil rich in humus, loose and breathable, and with good drainage.

Elm Bonsai Cultivation Methods: Elm Bonsai Care

Elm, especially old elm stumps grown in the wild, have undergone years of human chopping and hacking, or wind erosion and rain weathering, animal gnawing, etc., gradually forming many different and peculiar postures. Some have gnarled roots and are vigorous and ancient-looking; some turn decay into magic, with dead roots and new leaves, opening up a distinctive world of their own. They are excellent material for making bonsai. Here we offer our humble opinions on the production and care management of elm bonsai, for reference only.

First, stump selection must be strict. Choose small to medium-sized stumps as much as possible to facilitate balcony cultivation; the stump material must be fresh, and those that are decayed or have no fibrous roots should not be used. Newly dug old elm stumps should be planted in plain sandy soil or placed in clay pots to "nurture the stump," generally best done from late autumn to early spring (with the highest survival rate in the two or three months before bud break). Before planting, necessary pruning must first be done to the root system and branches; sticky sap often flows from the cuts (sap bleed), and if too much liquid seeps out, it will seriously affect the survival rate. The biggest shortcoming of all Ulmus varieties is that they easily bleed sap. If the stump material cannot effectively overcome this shortcoming before and after planting, then it is very difficult to ensure the stump's survival. For this, lacquer or wax can be applied to seal the cuts, or a layer of erythromycin ointment or sulfonamide ointment can be applied, then fine sandy soil sprinkled on. After the cuts are properly treated, do not pot them immediately; place them in a shady spot to air-dry for a few hours, letting the wounds naturally dry and form a protective film, which can greatly reduce the occurrence of sap bleed after potting. Elm likes dryness and fears moisture. After planting, press the soil firm; there is no need to water, only spray the branches with clean water 1 to 2 times a day, and after 3 to 4 days water thoroughly once. Afterward, water only when dry, and absolutely do not allow waterlogging.

Second, when shaping elm bonsai, based on the basic form of the old stump, use coiling, pruning and other means to create different styles of bonsai such as straight-trunk style, curved-trunk style, slanting-trunk style, waterside style, cascade style, wind-swept style, forest style, and root-on-rock style. Shaping can be done either during the dormant period after leaf fall or during the growing season, but the bud-break period must be avoided.

After the elm bonsai has taken shape, plant it in a purple clay pot before spring bud break, taking care to use loose, breathable, well-draining sandy soil rich in humus. It is best to mix yellow sand : pine needle soil : loess = 4:3:3; this soil is both breathable and water-retentive, and will not become waterlogged. Normally place it in a well-ventilated, well-lit spot for care, and keep the pot soil on the dry side. In summer when it is hot and dry, water can be sprinkled on the ground around the plant, but it is not advisable to spray water directly on the leaves, lest the leaves grow larger and lose their beauty. After a new stump survives, do not rush to fertilize; this is an important reason many people fail at nurturing stumps. Fertilizing should be done after autumn, and applying fully decomposed dilute liquid fertilizer is best.

Elm has strong sprouting ability and grows quickly, so it should be pruned often during the growing season, cutting away overly long and messy branches to maintain the beauty of the tree shape. The best viewing period for elm bonsai is when new leaves have just emerged. If all the leaves are removed in early to mid-August and fertilizer and water management is then strengthened, by late September new leaves will grow again, enhancing the ornamental value. In winter, move it to a bright, cool room, or bury the whole pot in the soil outdoors in a wind-sheltered, sunny spot, reducing watering so the plant can fully go dormant. During care, repot once every 2 to 3 years to keep the bonsai growing vigorously and full of life.

Chinese Elm

Chinese elm (Ulmus parvifolia) has a beautiful tree shape and an elegant posture, with mottled bark and fine, dense branches and leaves. It is very suitable for solitary planting or group planting in courtyards, or for pairing with pavilions and rockery. It can also be selected as a greening tree species for factory and mining areas. The Chinese elm wood is hard and can be used for industrial timber; the stem bark fiber is strong and tough and can be made into ropes and man-made fibers; the roots, bark, and young leaves used as medicine have the effects of reducing swelling, relieving pain, detoxifying and treating heat; applied externally, they treat burns and scalds from water and fire; the leaves can be made into a crude pesticide that can kill red spider mites.

Morphological Characteristics

Deciduous tree, or in winter the leaves turn yellow or red and persist until falling after the new leaves open the following year, up to 25 m tall, with DBH up to 1 m; crown broadly rounded, trunk base sometimes with buttress roots, bark gray or grayish-brown, splitting into irregular scaly thin flakes that peel off, revealing red-brown inner bark, nearly smooth, slightly uneven; current-year branches densely covered with short pubescence, dark brown; winter buds ovoid, red-brown, hairless. Leaves thick in texture, lanceolate-ovate or narrowly elliptical, rarely ovate or obovate, with unequal length and width on either side of the midrib, 1.7-8 (usually 2.5-5) cm long, 0.8-3 (usually 1-2) cm wide, apex acute or obtuse, base oblique, cuneate or rounded on one side; leaf surface dark green, glossy, hairless except for sparse pubescence in the sunken midrib, lateral veins sunken; leaf underside lighter in color, with short pubescence when young, later becoming hairless or with sparse hairs along the veins, or with tufts of hair in the vein axils; margin with blunt and neat single serrations from base to apex, rarely double serrations (as in the leaves of sprouting branches); lateral veins 10-15 per side, fine veins distinct on both surfaces; petiole 2-6 mm long, hairy only on the upper side. Flowers open in autumn, in 3-6 fascicles in the leaf axils or arranged in fascicled cymes; perianth cup-shaped in the upper part, tubular in the lower part; perianth segments 4, deeply cleft to the base or nearly the base of the cup-shaped perianth; pedicel very short, sparsely hairy. Samara elliptical or ovate-elliptical, 10-13 mm long, 6-8 mm wide, hairless except for the stigmatic surface at the apical notch; samara wing slightly thick, the stalk at the base about 2 mm long, the wings on both sides narrower than the nutlet portion; the nutlet portion located in the middle-upper part of the samara, its upper end close to the notch; perianth segments deciduous or remaining; fruit stalk shorter than the tubular perianth, 1-3 mm long, with sparse short hairs. Flowering and fruiting period August to October.

Growth Habits

Grows on plains, hills, mountain slopes and valleys. Light-demanding, drought-tolerant, able to grow on acidic, neutral and alkaline soils, but the most suitable habitat is neutral soil in a warm climate that is fertile and well-draining.

Geographical Distribution

Distributed in Hebei, Shandong, Jiangsu, Anhui, Zhejiang, Fujian, Taiwan, China, Jiangxi, Guangdong, Guangxi, Hunan, Hubei, Guizhou, Sichuan, Shaanxi, Henan and other provinces and regions. Also distributed in Japan and Korea.

Cultivation Management

Bonsai Production

(1) Material Collection and Propagation Measures

Artificial propagation: Chinese elm is usually propagated by seed. Seeds mature in October to November, when the fruit wings turn yellowish-brown; they should be collected in time, spread out to dry in the sun, the debris winnowed away, and stored dry in bags. Sow in March of the following spring, either by broadcasting or drilling. For drilling, the row spacing is 25 cm; choose a windless, sunny day for sowing, cover with fine soil just until the seeds are no longer visible, then cover with rice straw. Germination and emergence occur in about 30 days; uncover the straw in time and thin the seedlings appropriately. During the growing period, manage water and fertilizer well, weed and loosen the soil; the current-year seedlings can reach 30-40 cm tall. Young saplings have thin trunks, sparse branches, and relatively large leaves, so they are generally not suitable for making bonsai; it is better to cultivate them for several years, prune and shape them, and then pot them. In addition, Chinese elm can also be propagated by root cuttings to cultivate stump material, with relatively quick results; this is widely used in South China.

Wild collection: Chinese elm grows abundantly in the wilds and by the water in Jiangnan, and is even more common in limestone mountainous areas. One can select old tree stumps that have sprouted repeatedly after many years of cutting, especially elm stumps growing on barren slopes and poor land, by ditches, or in rock crevices in the wild; these grow slowly, are long-lived, and have been worked by natural wind and waves, with exposed roots, thick trunks, vigorous and twisted forms, slanting branches and leaves, small leaves, and an aged and quaint posture, making them the best. Collect before spring bud break, cut off unnecessary roots and branches, protect the secondary roots and fibrous roots, coat with mud slurry, and wrap with wet moss. After digging them back, choose a ventilated, well-lit place with loose, moist soil for deep burying and cultivation, called "nurturing the embryo." Wait until the root system develops and the new branches and leaves are luxuriant, then pot them and shape them. Using old stumps as bonsai material can shorten the bonsai production time, and the form is natural and quaint, unlike ordinary pieces, and they are easy to keep alive.

Cultivating wild old stumps collected from Chinese elm generally requires at least 2-3 years to take shape. Here we introduce a rapid cultivation method, especially suitable for bonsai growing. For Chinese elm stumps dug back in early spring, first plant them in clay pots for cultivation. After they survive, take care to remove unwanted buds at any time. Begin shaping from late April to early May. When the branches grow to 15-18 cm long, use fine metal wire for coiling and shaping, and pay attention to care management. When new shoots grow 4-6 leaves, pruning can be carried out, generally leaving only two leaves on each small branch, and then immediately apply a nitrogen fertilizer to encourage new shoots to sprout again. Repeat this pruning and fertilizing many times to make the leaves grow dense as quickly as possible. As the branches continuously thicken, the metal wire must be removed in time to prevent "wire bite." For branches not yet fixed in shape, they can be coiled again to secure their form. In this way, by September a Chinese elm stump bonsai can be preliminarily formed.

The key to this rapid shaping method is mainly to coil the branches while the xylem has not yet hardened, so production must be done with special care, and the thickness of the metal wire must also be chosen appropriately; when wrapping, it need not be pressed too tightly, to prevent bruising the delicate branches. In addition, the work of "nurturing the embryo" must also be done well, so as to achieve the goal of potting and making a bonsai in the same year the stump is dug.

(2) Potting Process

Pot selection: Chinese elm stump bonsai generally should use glazed ceramic pots, and purple clay pots may also be used. Pot shapes are diverse, determined by the tree shape, with rectangular pots being the most common. Plain and elegant colors are preferable.

Soil: It has no strict requirements for soil and has strong adaptability. For pot cultivation, loose and fertile garden soil or leaf mold is suitable; good breathability and water permeability are beneficial to root development and growth and help maintain the luxuriance of the old stump's branches.

Planting: Usually planted between February and March in spring before bud break, and also possible in autumn. When planting, prune the roots appropriately, cutting off overly long roots, and the plant can be raised appropriately. Chinese elm has a well-developed root system and is suitable for root-on-rock bonsai. Planting on rock is relatively difficult; generally one must choose stone material with relatively deep crevices (porous stone material can be artificially carved to create stone crevices), trim and arrange the tree roots, then embed them into the stone crevices, and use palm fiber to tie and bind the main thick roots to fix them. When rooting, be careful to avoid bruising the root system as much as possible, and moss can be used as padding. After rooting, smear wet river soil on the outside of the stone, then wrap it with moss, and then plant the tree roots together with the attached stone into the pot soil, and carefully care for 3-4 years. Once the root system embedded in the stone crevices has grown fully and filled the crevices, the binding can be removed; by then the root system and the stone have formed one body, and a Chinese elm root-on-rock bonsai is basically complete.

(3) Shaping Techniques

Processing: Chinese elm can be shaped by pruning and can also be processed in combination with coiling. Coiling can use palm fiber or metal wire. Because Chinese elm branches grow quickly, the coiling material should be removed in time to avoid "wire bite" that affects appearance. For old stumps collected in the wild, overly thick main trunks can be carved and reduced to reduce volume, match the side branches, and at the same time add an antique flavor. Chinese elm shaping is best done before spring bud break or during the plum rain season.

Tree shape: Chinese elm is highly plastic and suitable for processing into many kinds of tree shapes. Common ones include straight-trunk style, slanting-trunk style, lying-trunk style, cascade style, root-on-rock style, and combined planting style. The branches and leaves can be both coiled into pads and pruned into a natural-form canopy. Especially when creating root-on-rock Chinese elm bonsai, when conceiving the idea one can take a corner of the natural world, allowing a certain degree of exaggeration; to heighten the charm of a certain part, the tree can be placed above the rockery, with the tree as the main element and the stone as secondary, without being bound by the limitation of "a zhang of mountain, a chi of tree." The Lingnan school, Su school and Yang school in Chinese bonsai often use Chinese elm as the main tree species.

Care Management

Placement: Chinese elm should be placed in a spot with ample sunlight and good air circulation. In summer no shading is needed; in winter it can be placed outdoors, and to prevent the pot soil from freezing dry, the whole pot can be buried in the soil. Watering: Chinese elm likes moisture, and watering should be sufficient. In summer when temperatures are high and light is strong, water once in the morning and once in the evening, but do not let water accumulate in the pot. In autumn watering can be less; in winter, if the pot is buried in soil, there is no need to water.

Fertilizing: In winter apply farmyard manure or cake fertilizer once as a base fertilizer. From April to October (except during the plum rain season), apply a dilute organic fertilizer once every half month to maintain the nutrients needed for normal growth. Fertilizer should be mainly nitrogen and potassium.

Pruning: Chinese elm branches and leaves grow quickly; to maintain the bonsai shape, pruning should be done often. Generally when new bud branches extend to 5-6 cm, leave only 2-3 leaves and cut off the rest. To control growth, buds and shoot tips can also be pinched off at any time.

Repotting: Do it once every 2-3 years, best before spring bud break, and also possible in autumn. When repotting, remove about 1B2 of the old soil, prune some old roots, and fill with fertile, loose cultivation soil.

Pest control: Chinese elm has many pests, commonly including elm leaf beetles, scale insects, longhorn beetles, slug moths and bagworms. Spray 80% dichlorvos at 1500 times dilution for control; for longhorn beetles damaging the trunk, lime-sulfur mixture can be used to plug the insect holes.

Common Bonsai Disease Control

There are roughly two common and highly damaging diseases in the production of elm stump bonsai: root rot and branch witches' broom. Severe root rot directly causes stump death; witches' broom seriously affects the normal growth of the stump, making it difficult for branches to transition and take shape for many years, and in severe cases causes the stump body to shrink and the branches to lose form and be discarded. Root rot: The symptoms of elm stump root rot mainly appear during the growing season as leaves turning yellow and falling, branches gradually dying, and buds remaining dormant for a long time or stopping growth midway. When collecting wild elm stumps, great care must be taken to make the root cross-sections neat and not leave wounds, to prevent pathogen invasion. Elm stump bark is relatively thick and has more moisture; before temporary planting to nurture the stump, the root cross-sections must be properly dried, and a sterilizing solution can be applied to prevent root infection. When temporary planting, do not choose unclean soil with humus or unfermented matter. The soil should be sterilized. During stump nurturing, strictly control water and never let the roots be in an excessively moist or long-soaked state, as this easily promotes the growth of root rot fungi. When repotting, if black-brown decay is found in the root cortex, immediately scrape it clean with a sharp tool until fresh tissue is visible, and apply to the affected area a 25% wettable powder and carbendazim at a concentration of 1000 times dilution; after the solution air-dries, pot it. At the same time, necrotic roots should be cut off and burned, and care should be taken not to mix the scraped residue into the pot soil, to prevent reinfection. Only after the wounds heal and new roots are produced can fertilizer be applied, to enhance disease resistance. Witches' broom: Elm stump witches' broom mainly harms new shoots and leaves, showing symptoms such as clustered new shoots growing upright, diseased branches unfolding leaves early and small, and dense branching. The witches' broom pathogen overwinters as mycelium on the damaged shoots, and invades and causes damage when new shoots emerge the following year. In winter when pruning the elm stump, cut off the clustered shoots and burn them in a concentrated manner; before bud break in early spring, spray 5 degrees Be lime-sulfur mixture, with remarkable effect. Spraying can be done once a week during the growing season, and over five rounds it can eradicate witches' broom. During this period, besides avoiding rain, do not spray water on the branches and leaves; keep the leaf surface dry.

Landscape Value

Chinese elm has a slightly curved trunk, elegant mottled bark, gracefully drooping small branches, and leaves that turn red in autumn. It is a good ornamental tree and a greening tree species for factories and for greening around the four sides. It is often planted alone to form a scene and is suitable for planting by ponds and near pavilions, and can also be placed among rockery, except that it has relatively many pests and diseases. It has strong sprouting ability and is good material for making bonsai.

Its tree shape is beautiful, its posture elegant, its bark mottled, and its branches and leaves fine and dense, giving it high ornamental value. It is very suitable for solitary planting or group planting in courtyards or for pairing with pavilions, and it has good ornamental effects whether used as a shade tree, street tree, or made into bonsai. Because of its strong resistance, it can also be selected as a greening tree species for factory and mining areas.

Elm

Scientific name: Ulmus pumila Linn.
Family and genus: Ulmaceae, Ulmus.
Deciduous tree, native to the north, the tree can reach several meters tall: bark color ... has scale-like peeling, leaves elliptical, with serrated edges, dark green, leathery, and glossy. In March and April it produces small flowers; the fruit is flat and round, with membranous wings, called elm seeds, and can be eaten.
Elm has three types: large-leaf, medium-leaf and small-leaf. Among them, the large-leaf type is not welcome among bonsai creators because its leaves are large and thin, and its leaf color is inferior to the medium-leaf and small-leaf types, so it has been eliminated. The medium-leaf type grows faster than the small-leaf type, and the small-leaf type has higher ornamental value than the medium-leaf type, so both can coexist, to be selected by those who need them.
Elm is the most ideal tree species for creating Lingnan bonsai, and is one of the five famous trees in Lingnan bonsai (orange jasmine, Japanese bush cherry, Fujian tea, elm, and orange jasmine). It mainly has the following advantages.
① Fast growth speed (the fastest-growing of the five famous trees). Whether in the growth speed of the embryo material or in using the technique of trunk chopping and branch training for cultivation, this tree has a relatively fast speed.
② Small leaves, beautiful leaf shape, and lovely dark green leaf color, meeting the requirements for making bonsai.
③ Good callus formation and high plasticity; relatively large wounds can also heal. Using this characteristic, the tree embryo stump can be transformed. If it needs to be reduced, after chopping off a part it can also heal naturally; if it needs to be enlarged, the "striking" method and the "bark lifting" method can be used, using its callus proliferation tissue to become rugged nodules, which not only has a vigorous beauty but can also give the broad trunk part a sense of enlargement.
④ Branches are soft and not easily broken, which is favorable for shaping and coiling.
⑤ The root base is well developed and can be arbitrarily transformed using the callus principle to meet the requirements of various tree styles, and it is also ideal for creating the root-on-rock style.
⑥ High sprouting rate. Elm is the species with the highest sprouting rate among all tree species, with latent buds all over its body. During the bud-break period before the Start of Spring, buds will sprout on any trunk that has wounds. This makes it very convenient to choose and decide the positions of bonsai branches. If a branch is needed at a certain position, make a hole there until the xylem is visible, and later a bud will sprout there. After it grows into a branch, the wound will heal naturally and will not leave very obvious traces.
2. Habits and Care
Elm likes sunlight and is cold-tolerant; it needs both moist soil and good drainage, especially during transplanting, to prevent waterlogging and root rot.
Elm has strong sprouting ability. During the suitable season (around the Start of Spring), buds will sprout at any position with a wound. During the unsuitable season, the whole plant must be leafless (all leaves removed) for sprouting to achieve the ideal result. If single-branch pruning is carried out during the unsuitable season (while other branches still carry leaves), it will cause failure to sprout. Therefore, when shaping, once a certain branch has reached the required size, the method of early inhibition is mostly used (binding branches and leaves to limit photosynthesis) to limit the growth of this branch. Only when all the branches of the whole plant are in proportion are they all cut together, so that all branches of the whole plant sprout together, and thus each branch can grow in a balanced way.
When a certain branch is affected by disease and shrinks, the leaves of the whole tree can also be removed, which can prompt the diseased branch to sprout together with all the branches, resolving the disease of a single diseased branch.
Digging and transplanting elm should be carried out each year during the period from Minor Cold to Major Cold. Digging during this period, even if the root system of the elm suffers relatively great damage, the elm can still survive. The farther away from Major Cold, the lower the survival rate of transplant regeneration.
3. Propagation Methods
Elm has become a cultivated species in the south. There are two propagation methods. One is air layering (commonly known as ring-barking), which can be carried out throughout the year except during the dormant period. Air layering propagation can produce quite good shaped stems, but the stump base and root system are not as beautiful as stumps propagated from root cuttings, and they are mostly used as commercial bonsai. The second propagation method is root cutting. Take from each year during the period from Minor Cold to Major Cold
the root pieces cut off when digging elm stumps (regardless of size); cut or make each about 10 cm long, and plant them immediately in fully draining, breathable soil; after watering thoroughly to settle the roots (cover them in rainy weather), in about a month they will sprout and grow. With routine management, transplant and interplant the following year. For elm propagated from root cuttings, after several years the stump base is strong and rugged, with deep cracks, and the roots are gnarled and interlocked, able to create works with various artistic personalities.
4. Pest and Disease Management
Common pests of elm include red spider mites, elm oystershell scale, and cottony cushion scale. The damage symptom of red spider mites on elm is dull, dry leaf color; under transmitted sunlight the leaves can be seen eaten into a network pattern (the mites are so small they cannot be seen by the naked eye). This makes the damaged tree unable to sprout and grow for a long time. The damage symptom of elm oystershell scale is that the elm branches are covered with white filamentous material; the damaged branches become thin and dried, and if untreated over time, the whole branch will wither (for control methods refer to the pest control section). Next is sunscald: under strong sunlight exposure, elm bark is easily scorched, so measures must be taken to protect the sun-exposed bark and overcome this disease.
The biggest disease of elm bonsai is branch dieback. This disease mostly occurs after the elm has become a bonsai. A perfectly good bonsai, you watch it wither branch by branch, ruined as a scene; if it cannot be overcome in time, the loss is great.
① The main causes of branch dieback in elm (the same for Acacia confusa) are: elm is a tree, grows quickly in the ground, and has a very developed root system. After it is transplanted into a pot (especially a shallow bonsai pot after becoming a bonsai), the pot holds little soil, and the root system quickly fills the entire pot and intertwines into a "root nest." This "root nest" is tight, water can hardly penetrate inside, and the water poured merely overflows at the soil surface, creating water deficiency and fertilizer deficiency, causing the tree's vigor to gradually weaken. At the same time, after the work has taken shape, the branches are dense, nutrient consumption is large, and ventilation is poor, making the branches thin and weak with weak disease resistance, easily attracting pests. These adverse factors are the causes of branch dieback in elm. This disease first shows as delayed sprouting (normal growth should be buds maintaining a tender green sprouting state), followed by yellow leaves and defoliation due to water and fertilizer deficiency. The branches inside (with poor ventilation) first age and shrink back, gradually developing into disease of the whole plant. ② The way to solve branch dieback in elm (the same for Acacia confusa) is: pay close attention to the plant's growth state. If the above conditions are found, use a pick to probe the soil; once it is confirmed that water and fertilizer deficiency is caused by the tight "root nest," immediately take measures: use a pick to loosen the soil deep into the "root nest," so that water and fertilizer can effectively seep into the interior of the soil. At the same time, use foliar feeding and spray more water on the leaves
to alleviate the symptoms. When the dormant period is reached, immediately repot, cut away as much of the excess root system as possible, and replace with new soil; the disease will naturally improve. Experience has proven that elm bonsai should be repotted, root-pruned, and soil-changed once every year (during the period from Minor Cold to Major Cold) to ensure normal growth.

Planting method for raw elm stumps: * Apply glue to the cut ends, press firm with plain yellow mud, do not water. Place in a dark place. Water after 10 days. Shade. Mine has been planted for a full month and is growing luxuriant branches and leaves.

Sap flow must be prevented; the cuts must not contact water within one week.

* Cut all branches and leaves, prune all at once, plant in pure sand (semi-moist), do not water for the time being, place indoors in a cool place, spray water mist on the branches several times a day, and wait until buds sprout on the branches and only water if the pot is short of water, gradually moving from indoors to a shaded outdoor spot, then gradually to normal sunlight (avoiding noon), and after about a month or more, enter normal management as appropriate.

Elm is distributed throughout China, and is generally transplanted during the dormant period in winter and spring, with the highest survival rate before bud break in February and March. Before production, it should first be planted in sandy soil to "nurture the stock." Before planting, the branches and root system must be pruned; a sticky sap often flows from the wounds, and if too much of this sap seeps out, it will seriously affect the survival rate. Wax, lacquer, etc. can be applied to the cuts, or a layer of erythromycin ointment can be applied, then fine sandy soil sprinkled on to prevent the sap from flowing out. However, it must never be soaked in water, otherwise it will worsen the sap loss, causing the roots to rot and the plant to die. After planting, press the soil firm, but there is no need to water; instead, spray the trunk with clean water 1 to 2 times a day, and after 2 to 3 days water thoroughly once. Afterward, place the plant in a ventilated, well-lit place for care, watering only when dry and watering thoroughly when watering, and strictly forbid waterlogging of the soil. Elm bonsai can be shaped either during the growing season or during the dormant period, but the bud-break period should be avoided to prevent excessive sap loss that would affect plant growth. The form can be worked into various styles of bonsai based on the basic shape of the stump, such as straight-trunk style, curved-trunk style, slanting-trunk style, withered-trunk style, waterside style, cascade style, and forest style. The canopy can use either the elegant, loosely branched natural style, or the rounded large-tree form, and can also be worked into a neat round-pad shape. The shaping method combines wiring and pruning: first use metal wire to coil out the basic form, then prune carefully.

Apply erythromycin or seal with wax to the wound cross-sections, spray water on the leaves, and it is not too late to water after waiting a few more days. Otherwise, if the sap bleeds, it is very difficult to keep alive. Add plant ash to the cut roots; this can stop the sap. After planting, water after one week, add soil, then seal the soil with plastic sheeting and leave it alone. Around March 20 next spring it will sprout. (Transplanting has caused injury, so immunity is a bit weaker. Just put a plastic bag over the top. Remove it when the buds have 2-3 leaves, around mid-April; do not water before that.)

Pruning Methods for Elm Bonsai

Elm bonsai has become more and more popular in recent years. Because elm bonsai not only has ornamental value but can also help purify the air and reflect a high-quality lifestyle interest, people of different age groups have begun cultivating elm bonsai. The editor will introduce the pruning methods for elm bonsai; interested friends can study together.

Elm Bonsai

Most elm stumps are dug from the wild. You can choose ones with good shape and growth according to your own preferences; they can be staggered in height and layered, which is conducive to determining the later shaping. After all, most bonsai nowadays are grown as ornamental pieces. In addition to this, elm can also be cultivated by grafting and cuttings, with a high survival rate and easy survival.

The best time to transplant bonsai is spring or autumn. Before transplanting, a preliminary pruning of the elm's roots and leaves is needed, which is conducive to rapid root development. For the care of elm bonsai, elm likes sunlight but is also very cold-tolerant, and can be placed outdoors with good air circulation and ample sunlight. At the same time, the pot soil needs to be kept moist, and water can be appropriately sprayed into the soil. Generally water is not sprayed on the leaves, for fear that the leaves will grow too large and affect the overall shape of the elm bonsai. Direct watering would cause water to accumulate in the bonsai, which is not conducive to the elm's root growth. Bonsai generally chooses the Spring Equinox in spring to repot and loosen the soil, and repotting about once every three years is suitable. Fertilizing is once each year during the growing season. To prevent pests, some pesticide solution can also be sprayed. Winter is the most suitable time for pruning elm, because in winter all the leaves have fallen, leaving only clearly visible branches. For elm that needs pruning, you can prune according to the growth of the main trunk and branches plus the overall shape you want to achieve. Usually you can first prune away the excess branches that interfere with the tree's shape, and also prune poorly growing branches, dead branches, diseased branches, etc.