What to do when Sorbaria sorbifolia gets pests? 2 pests and 2 diseases and how to control them

When people grow Sorbaria sorbifolia, the last thing they want to encounter is pests and diseases. Such problems are extremely harmful to Sorbaria sorbifolia. They not only greatly affect its ornamental value, but if left untreated for a long time, they can also cause the plant to wither and die. So what should be done when Sorbaria sorbifolia gets pests? How should pest and disease control for Sorbaria sorbifolia be carried out? Below, the editor will help everyone understand.

I. What to do when Sorbaria sorbifolia gets pests

To know what to do when Sorbaria sorbifolia gets pests, we first need to know what kind of pest it is, so we can deal with it in a targeted way, because the treatment methods for each pest and disease are different. The specific details are introduced in the pest and disease control section for Sorbaria sorbifolia below. Let us take a look.

II. Pest and disease control for Sorbaria sorbifolia

Pests

1. Scarab beetles

Scarab beetles are soil-dwelling pests and are a relatively common type among the pests and diseases of Sorbaria sorbifolia. These pests mainly feed on the main roots and stems of Sorbaria sorbifolia, gradually eating away at the base of the plant, causing the plant to become incomplete and die.

Control method: When dealing with this pest, we can spray the soil with a 1000-fold solution of 40% omethoate. After spraying, loosen the surface soil so the solution can penetrate better. This pesticide kills scarab beetles on contact.

2. Planthoppers

Among the pests and diseases of Sorbaria sorbifolia, planthoppers are an extremely harmful pest. They mainly feed on the sap inside the plant, gradually sucking it out, causing the plant to lose a large amount of nutrients, leading to shriveling and cracking, and finally causing the plant to gradually wither and die.

Control method: This pest has an extremely strong reproductive capacity, so it must be dealt with promptly. Generally, we can use a 1000-fold solution of 90% trichlorfon to directly spray and kill it.

Diseases

1. Leaf spot disease

This is a relatively common disease among the pests and diseases of Sorbaria sorbifolia. When it occurs, many brown spots appear on the leaves, and many mold-like substances also appear on the underside of the leaves. As time goes on, it gradually spreads, finally causing the plant to wither and die.

Control method: When controlling leaf spot disease, we can use a 500-800-fold dilution of 50% thiophanate to spray Sorbaria sorbifolia. Generally, spray once every 10-15 days, and after 2-4 times it can basically recover.

2. Powdery mildew

Powdery mildew is a disease caused by fungi. When this disease occurs, many powdery white mold spots appear on Sorbaria sorbifolia. This phenomenon seriously affects photosynthesis in Sorbaria sorbifolia, gradually causing leaf drop and plant withering. This shows the harmfulness of powdery mildew among the pests and diseases of Sorbaria sorbifolia.

Control method: When controlling powdery mildew, we can use an 800-1000-fold solution of 50% amobam to spray Sorbaria sorbifolia. Generally, spray once every 7-10 days, and after 2-3 times it can recover.

Sorbaria sorbifolia (L.) A. Br. Sorbaria sorbifolia profile: how to grow Sorbaria sorbifolia / how to propagate Sorbaria sorbifolia

How to grow a Sorbaria sorbifolia bonsai: cultivation methods for Sorbaria sorbifolia

Sorbaria sorbifolia is native to northern Asia. It is a shrub-type, deciduous broadleaf shrub plant. It likes sunlight and also has strong shade tolerance. It is cold-resistant, moisture-resistant, and drought-resistant. Sorbaria sorbifolia is mostly planted as a single plant in gardens and courtyards. Below is an introduction to how to grow a Sorbaria sorbifolia bonsai and a detailed introduction to cultivation methods for Sorbaria sorbifolia.

Introduction to Sorbaria sorbifolia

Sorbaria sorbifolia is native to northern Asia and is distributed in places such as Hebei, Gansu, Shandong, Shanxi, Inner Mongolia, and Jiangsu in China. It is a shrub-type, deciduous broadleaf shrub plant. It likes sunlight and also has strong shade tolerance. It is cold-resistant, moisture-resistant, and drought-resistant. It is not demanding about soil and can grow normally in ordinary soil, while growing more vigorously in moist, fertile soil. It grows quickly, has strong suckering ability, and tolerates pruning.

Sorbaria sorbifolia belongs to the genus Sorbaria in the Rosaceae family. It got this name because its flowers are dense and snow-white when it blooms. It is also called “snow willow” because its leaves resemble willow leaves and its flowers are white like snow. Sorbaria sorbifolia is mostly planted as a single plant in gardens and courtyards. Generally, no fertilization is needed, but it must be watered frequently. Especially during droughts in spring and summer, the soil must be kept moist.

Before winter, water thoroughly with winter water. In high-cold regions, it should be protected for overwintering. Other management is relatively extensive. Sorbaria sorbifolia has a full plant clump and elegant branches and leaves. Its value lies in producing elegant white flowers in midsummer when flowers are scarce, and its flowering period is very long. In particular, it has a killing or inhibiting effect on many harmful bacteria and is suitable for planting in various garden green spaces. Especially because of its shade tolerance, it is a flowering shrub species for greening the shaded north side of high-rise buildings and various structures in northern cities.

I. Morphological characteristics

Sorbaria sorbifolia is a shrub up to 2 m tall, with spreading branches; branchlets cylindrical, slightly flexuous, glabrous or slightly pubescent, green when young, dark reddish brown or dark yellowish brown when old; winter buds ovoid, apex rounded-obtuse, glabrous or apex slightly pubescent, purplish brown, with several alternate exposed scales.

Pinnate compound leaves, leaflets 11-17, including petiole 13-23 cm long, 10-13 cm wide, leaf rachis slightly pubescent; leaflets opposite, 2-2.5 cm apart, lanceolate to ovate-lanceolate, 5-7 cm long, 1.8-2.5 cm wide, apex acuminate, rarely caudate, base subrounded or broadly cuneate, rarely oblique, margin sharply doubly serrate, both surfaces glabrous or nearly so, pinnate reticulate veins, with 12-16 pairs of lateral veins, conspicuous abaxially; petiolules absent or nearly so; stipules herbaceous, ovate-lanceolate to triangular-lanceolate, apex acuminate to acute, margin irregularly serrate or entire, 8-13 mm long, 5-8 mm wide, slightly pubescent outside.

Terminal large dense panicle, branches nearly erect, 10-20 cm long, 5-12 cm in diameter; peduncle and pedicels covered with stellate hairs or pubescence, gradually falling off in fruit stage, nearly glabrous; bracts ovate-lanceolate to linear-lanceolate, 5-10 mm long, 3-5 mm wide, apex long acuminate, margin entire or with shallow teeth, both surfaces slightly pubescent, gradually falling off in fruit stage; pedicels 5-8 mm long; flowers 10-12 mm in diameter; calyx tube campanulate, base slightly pubescent on the outside; sepals triangular-ovate, apex obtuse or acute, sepals about as long as the calyx tube; petals oblong or obovate, 5-7 mm long, 3-5 mm wide, white; stamens 40-50, about 1.5-2 times as long as the petals, inserted on the edge of the disc; carpels 5, glabrous or slightly pubescent.

Follicles oblong, with a terminal curved style, about 3 mm long, fruit stalk erect; sepals persistent, reflexed, rarely spreading. Flowering period July-August, fruiting period September.

II. Ecological Habits

Sorbaria sorbifolia is cold-resistant, tolerant of partial shade, and tolerant of pruning. It grows well in well-drained sandy loam. It grows fast and suckers easily, making it a good summer flowering plant.

Most plants in the Rosaceae family are sun-loving, and Sorbaria sorbifolia is no exception. It likes sunlight and tolerates a certain degree of waterlogged and moist environments, but should not be waterlogged for long periods. It is not demanding about soil and tolerates a certain degree of salinity and alkalinity, making it suitable for growing in the Shanghai area.

Propagation Methods of Sorbaria sorbifolia

Propagation of Sorbaria sorbifolia is mainly by division, and can also be done by sowing. However, because the seeds are very small, the sowing method is mostly not used. Division propagation is generally carried out before bud break in spring or after leaf fall in autumn. Dig out the suckering seedlings clustered at the base of the plant together with their roots, take 3-5 plants as a clump, and replant them separately.

When planting, apply 2 shovelfuls of compost in the hole as base fertilizer, and water thoroughly after planting. Afterward, water about once a week until established. Clumps over 5 years old can grow into a very large crown width; in early spring before budding, dig away the soil around the old clump, then cut each root sucker seedling away from the parent plant one by one, dig them out, and move them to a nursery for cultivation. After 1 year they can become seedlings ready to leave the nursery. For large-scale propagation of seedlings, the sowing method can be used. Store the seeds dry and sow in spring the following year.

1. Division Propagation

During its growth, Sorbaria sorbifolia has the characteristic of easily sprouting root suckers, and division propagation can be carried out in early spring in March and April. Select robust plants free of pests and diseases and with many tillers as mother plants.

The method is: dig away the soil around the roots of a mother plant over 5 years old, insert a knife from the middle of the gap, and separate the tillers from the mother plant; each clump can be divided into 5 to 7 plants. The separated root sucker seedlings must have complete roots; if the lateral roots of the root sucker seedlings are fine and numerous, some should be properly cut off when planting. This propagation method has a high survival rate, forms quickly with fast results, and is relatively simple to manage, but the number propagated is limited. After division, water thoroughly, move the plants to a slightly shaded place, and after one week gradually place them in sunlight for normal care.

2. Cutting Propagation

This method is suitable for large-scale propagation and can be carried out all year round, but cuttings root fastest and have a high survival rate in March and October. For the cutting soil, generally use 5 parts garden soil, 4 parts humus soil, and 1 part sand, mix them and make trenches and beds for open-field cuttings. For the cuttings, choose current-year or biennial mature branches from robust plants, cut them into 15-20 cm lengths, and keep 4-5 buds or leaves. When inserting, insert 2/3 of the cutting into the soil, leaving only the top one or two buds or leaves above the soil surface. The cut end of the cutting should be flat, cut into a horseshoe shape, inserted immediately after cutting, press down the soil at the base of the cutting, and water thoroughly once. After that, spray water 1-2 times a day and keep the soil moist regularly. After 20 days, reduce the frequency of spraying to prevent excessive moisture from causing branch rot. After about 1 month, they can root and be transplanted.

3. Layering Propagation

In March and April, bend the branches on the outer edge of the mother plant directly into the soil; the part pressed into the soil can also be ring-barked or nicked to promote rapid rooting. After new roots grow, separate them from the mother plant and transplant during the spring or autumn tree-planting season.

Cultivation Methods of Sorbaria sorbifolia

Sorbaria sorbifolia has strong adaptability and does not require much fertilizer. Apart from newly planted plants needing a small amount of base fertilizer, no further fertilizer is needed afterward, but watering is required. Generally, water thoroughly 2-3 times from bud break to flowering, and water 2-3 times from the beginning of autumn to before frost, including 1 anti-freezing watering. In summer, water according to drought conditions; when there is a lot of rain, there is no need to water. After the flowers fade, the inflorescences turn yellow and dry, affecting the appearance, so the spent inflorescences should be cut off to keep the plant clean and tidy and to avoid the spent inflorescences competing with the plant for nutrients and water. After autumn or in early spring, diseased and pest-infested branches and old, weak branches should also be cut off; annual branches can be heavily pruned to promote branch renewal and abundant flowers and lush leaves.

① It is not demanding about soil, but it grows better and blooms more abundantly when cultivated in deep, fertile sandy loam.

② It does not require much fertilizer. When first cultivated, sufficient base fertilizer should be applied to meet its growth requirements, and generally no additional topdressing is needed. Afterward, combined with winter management, applying base fertilizer once every 1-2 years is sufficient.

③ Water promptly during spring droughts; during summer and autumn droughts, water thoroughly to keep the soil from drying out; before winter, water once with anti-freezing water.

④ After flowering, promptly prune away remaining flower branches, diseased and pest-infested branches, and old, weak branches to keep the plant shape tidy, avoid nutrient consumption, and promote robust growth with abundant flowers and lush leaves.

How to Grow Sorbaria sorbifolia Bonsai

The care of Sorbaria sorbifolia bonsai mainly involves details such as temperature, watering, and potting soil. The maintenance of bonsai Sorbaria sorbifolia is not as extensive as field planting; you must always pay attention to whether the potting soil needs watering, and also prune the branches and leaves regularly, so that the advantages of the Sorbaria sorbifolia bonsai can be displayed.

I. Seedling Raising Methods

1. Cuttings

Cutting propagation of Sorbaria sorbifolia is best carried out after leaf fall in autumn. The seedbed can be chosen in a sunny, wind-sheltered place; after deep plowing, break up the soil finely and level it. After the seedbed is made, fill the seedbed with 70 cm of sterilized plain sandy soil. When cutting, select robust branches grown in the current year, each section about 12-15 cm long, spray water after inserting,

cover with plastic film, and keep the substrate moist and the seedbed temperature stable: Sorbaria sorbifolia has strong regeneration ability, a high survival rate after cutting, and rapid growth and development. It begins to sprout in early spring the following year, and by autumn it can be potted.

2. Division

For Sorbaria sorbifolia plants, generally after 3-5 years of cultivation, they must be cut and divided for replanting, and the time is best in September-October. When dividing, dig up the Sorbaria sorbifolia with a soil ball, remove excess attached soil, and expose all the roots. Then, according to the gaps between the roots of the plant, use a sharp knife to cut them into several clumps, smear the cuts with sulfur powder, and properly prune away excess stems, branches, and long roots. And according to the needs of greening and beautification, carry out single-plant cultivation. After planting, water thoroughly, then water once more every week, generally 3 times in a row, and Sorbaria sorbifolia will survive.

II. Cultivation Methods

1. Potting Soil

For potting soil, it is best to choose loam with good permeability, strong drainage, and relatively fertile soil. Apply organic fertilizer once in late autumn and early winter, and apply phosphorus and potassium fertilizer once before flowering. Water moderately at ordinary times to keep the potting soil moist; it must not be overly wet for a long time, and even less should it be waterlogged. Potted plants should be placed in direct sunlight as much as possible. Low-temperature dormancy in winter is a physiological need, so they must not be placed in a greenhouse, lest it affect the next year's growth and flowering. Place them in an open, wind-sheltered, sunny spot, or bury the pot with soil, and they can overwinter safely. Prune every year after leaf fall until before the next year's budding, cutting off diseased and damaged branches, dry and dead branches, and the thin and weak among overly dense branches. Shorten overly long branches to maintain a good plant shape, ventilation, and light transmission, which is beneficial for flowering.

2. Temperature and Light

When cultivating Sorbaria sorbifolia, note that it likes a warm, humid environment and sunlight. Adult plants can also tolerate cold and partial shade. For seedlings from autumn cuttings, by the following summer, it is exactly the period of growth for young shoots and leaves. The grower should, according to the position of the seedbed, pay attention to building a shade shed to avoid direct strong sunlight, so that scattered light is sufficient. For flowering and fruiting plants, sunlight should be increased to make photosynthesis vigorous and promote vigorous plant growth.

The most suitable temperature for Sorbaria sorbifolia growth is 18°C-32°C. If the temperature is suitable, light is sufficient, and reasonable water and fertilizer management is matched, Sorbaria sorbifolia can enter a luxuriant growth period, and on the crown, pearl-like flower buds bloom brilliantly. Sorbaria sorbifolia is cold-resistant, and no cold protection measures are needed in winter; generally it can overwinter in the open field.

3. Fertilization

Sorbaria sorbifolia does not require much fertilizer. When first cultivated, sufficient base fertilizer should be applied to meet its growth requirements, and generally no additional topdressing is needed. Afterward, combined with winter management, applying base fertilizer once every 1-2 years is sufficient.

4. Pruning

After the flowers of Sorbaria sorbifolia fade, the inflorescences turn yellow and dry, affecting the appearance, so the spent inflorescences should be cut off to keep the plant clean and tidy and to avoid the spent inflorescences competing with the plant for nutrients and water. After autumn or in early spring, diseased and pest-infested branches and old, weak branches should also be cut off; annual branches can be heavily pruned to promote branch renewal and abundant flowers and lush leaves.

5. Watering

Water promptly during spring droughts; during summer and autumn droughts, water thoroughly to keep the soil from drying out; before winter, water once with anti-freezing water.

Pest and Disease Control of Sorbaria sorbifolia

After the plants have grown, pest and disease control work should be carried out promptly, and early control should be achieved to promote healthy plant growth. The main diseases of Sorbaria sorbifolia are: leaf spot, powdery mildew, and brown spot. The main pests to prevent and control are: scarab beetles, and leafhoppers such as the spotted leafhopper.

1. Leaf Spot

When the disease occurs, round or irregular brown spots appear on the leaves, and sparse brown mold-like substances grow on the spots on the underside of the leaves.

Control method: spray a 500-800 times diluted solution of 50% thiophanate.

2. Powdery Mildew

When the disease occurs, white or grayish-white flour-like substances appear on the leaves. In severe cases, young tips curl, leaves become uneven, and they fall early. Flowers are small and do not open, and the flower form is deformed, curled, and withered.

Control methods:

(1) In late autumn, remove diseased and residual plants to reduce sources of the pathogen;

(2) Pay attention to ventilation, reduce air humidity, strengthen light, apply more phosphorus and potassium fertilizer, and enhance resistance;

(3) After the disease occurs, promptly cut off the affected parts, or pull out diseased plants and burn them;

(4) Spray chemicals. During the dormant period, spray an equal-amount 1% Bordeaux mixture; in the early stage of the disease, spray 70% thiophanate-methyl 800 times solution or 50% amobam 800-1000 times solution.

3. Brown Spot

Sorbaria sorbifolia brown spot mainly damages leaves. At first, brown round to irregular lesions are scattered on the leaf surface, with darker edges and a clear boundary with healthy tissue. Later, sparse small dark brown to blackish-brown mold spots, namely the pathogen fruiting bodies, grow on the underside of the leaves. The pathogen overwinters as mycelium or conidia on affected leaves, and the following year produces conidia that spread to neighboring plants by wind and rain. It generally occurs easily when the tree is weak or ventilation is poor.

Control methods

(1) From July-September, spray 65% zineb wettable powder 600 times solution or 70% mancozeb wettable powder 500 times solution, 25% benomyl emulsifiable concentrate, or 12% copper green emulsifiable oil 600 times solution

(2) Strengthen management and improve disease resistance.

(3) In late autumn and early winter, collect diseased leaves and burn them centrally to reduce the source of inoculum the following year.

4. Scarab Beetles

Small green flower scarab beetles and others bite and eat leaves, flower buds, and flowers, causing leaves to become incomplete.

Control methods:

(1) Taking advantage of the adults' death-feigning behavior, shake the branches in the early morning or evening to capture and kill them;

(2) During the adult occurrence period, spray 40% omethoate 1000 times solution, or 50% malathion 1000 times solution.

(3) Taking advantage of the adults' habit of entering the soil, scatter 2.5% phosmet powder around the plants, then loosen the surface soil so that the adults contact the chemical and die of poisoning.

5. Spotted Leafhopper

Adults and nymphs often gather on the underside of tender leaves to pierce and suck sap. Affected leaves show symptoms such as perforation, rupture, curling, or thickening depending on leaf age.

Control methods:

(1) In winter, cut off overly dense branches and dead branches and burn them to reduce pest sources;

(2) During the peak occurrence period of adults, use insect nets to capture and kill them;

(3) During the damage period of nymphs and adults, spray 90% trichlorfon 1000 times solution, or 40% dimethoate emulsifiable concentrate 1200 times solution to kill them.