Overview
Crataegus rotundata Sarg., commonly known as round-leaved thorn or cherokee thorn, is a small deciduous tree or shrub that belongs to the rose family.
Appearance
The round-leaved thorn is a small, compact, and slow-growing plant that can reach a height of up to 10 feet. The tree has an oval to rounded crown, and the branches form a dense structure. It has deeply lobed leaves that are round to oval in shape, with serrated edges, and glossy dark green color of a length between 1-2 inches. The plant produces small white or pinkish flowers in clusters from late spring through early summer. The tree bears small, red fruit that resembles miniaturized crab apples, which ripen in late summer and early autumn.
Origin and Habitat
The round-leaved thorn is native to the southeastern United States and can be found growing in woodlands and along streams, usually in acidic, moist soils. It can tolerate drought, limited soil nutrients, and urban pollution. It has been introduced as an ornamental plant in Europe and has been naturalized in several regions.
Uses
The round-leaved thorn has an extensive use in traditional medicine in the United States. The plant's bark, leaves, and fruits contain flavonoids, tannins, and other chemicals that have cardiovascular benefits, including lowering blood pressure and improving blood circulation. The fruit is also used in making jellies and jams. In gardening, the tree is used as a hedge or accent plant, providing a showy display of white flowers and red fruit. The wood is hard, strong, and durable and is used in making tool handles and furniture.
Light Requirements
Crataegus rotundata Sarg. prefers full sunlight for vigorous growth and establishment.
Temperature Requirements
Crataegus rotundata Sarg. is cold-hardy and can withstand freezing temperatures down to -50°F. However, it can also tolerate warm and humid weather conditions.
Soil Requirements
The plant requires well-draining soils such as sandy loam, loam, or clay loam soils. It can also grow in slightly alkaline to slightly acidic soils with a pH range of 6.0 to 7.5. The soil should be fertile and rich in organic matter.
Cultivation Methods
Crataegus rotundata Sarg., commonly known as round-leaved hawthorn, is a deciduous shrub that can grow up to 6 metres tall. It can tolerate a wide range of soils but prefers well-drained loamy soils.
It prefers full sun but can tolerate partial shade. The plant can be propagated through seed germination or by taking stem cuttings during the dormant season, which can then be rooted or grafted.
Watering Needs
Crataegus rotundata Sarg. likes regular watering but not waterlogged conditions. Newly planted hawthorn plants require more frequent watering until they have established deep roots, typically for the first 2-3 years. During periods of prolonged drought, it is important to water the plant deeply at least twice a month.
Fertilization
It is best to fertilize hawthorn plants once a year in late winter or early spring before new growth begins. The appropriate fertilizer for Crataegus rotundata Sarg. is a balanced slow-release fertilizer, with an N-P-K ratio of 10-10-10 or 16-12-12. A well-composted organic matter can also be added to help retain moisture and provide nutrients.
Pruning
Pruning is essential for shaping and maintaining healthy Crataegus rotundata Sarg. plants. It is best to prune the plant during its dormant season to prevent damage to new growth. Pruning should focus on removing dead, diseased, or damaged wood, as well as promoting air circulation by thinning out crowded or crossing branches.
Hawthorn plants should be pruned lightly in their first year to promote bushiness, and any crossing branches removed. Subsequent pruning can be done in late winter or early spring, and the objective should be to achieve symmetry and retain the plant's natural growth habit.
Propagation of Crataegus rotundata Sarg.
Crataegus rotundata Sarg. can be propagated through several methods:
Seed Propagation
The most common method of propagation for Crataegus rotundata Sarg. is through seeds. The seeds are sown in well-prepared beds during early spring. The seeds generally take about a month to germinate. Once the seeds have sprouted, they can be transplanted into individual containers or directly to the desired planting spot.
Vegetative Propagation
Crataegus rotundata Sarg. can also be propagated through vegetative methods. The most common methods are through cuttings and layering.
Cuttings: Hardwood cuttings are taken during winter. The cuttings should be about 6 to 8 inches long and should be taken from healthy, disease-free plants. These cuttings are then planted in a well-prepared bed in late winter or early spring. The cuttings require misting and well-drained soil for better establishment. Layering: Layering is another form of vegetative propagation that is commonly used for Crataegus rotundata Sarg. In this method, a low-lying branch is bent down to the ground and a small portion of the stem is exposed by removing the bark. This exposed portion is then covered with soil or mulch, which will encourage root formation. Once the roots have developed on the exposed portion, the branch can be cut off from the parent plant and transplanted elsewhere.
Regardless of the method used, the plants must be watered regularly for at least two to three years after planting to ensure proper establishment.
Disease and Pest Management for Crataegus Rotundata Sarg.
Crataegus rotundata Sarg., commonly known as the roundleaf hawthorn, is a resistant plant that is not usually affected by pest or disease issues. However, in certain conditions, some diseases and pests may appear and cause damage to the plant.
Common Diseases
Fire blight: This bacterial disease appears as dark brown or blackened branches with wilted leaves and flowers. It spreads quickly, and the infected branches should be pruned to prevent further contamination. To prevent fire blight, avoid overhead watering, maintain good air circulation, and remove dead or infected wood during the dormant season.
Rust: This fungal disease appears as small, yellow spots on the leaves and stems. As the disease progresses, the spots turn rust-colored, and the leaves may fall off. To manage rust, remove any infected leaves and stems and avoid overhead watering. Applying fungicides can also help prevent the spread of rust.
Leaf spots: These fungal diseases appear as circular brown or black spots on the leaves. They are caused by cool, wet weather, and can be prevented by ensuring good air circulation around the plant. Remove any infected leaves and stems promptly to prevent the spread of the disease.
Common Pests
Aphids: These sap-sucking insects appear as small, green or black bugs on the leaves and stems. They can be controlled by spraying the plant with a strong stream of water or applying insecticidal soap or oil. Natural predators such as ladybugs and lacewings can also help control aphids.
Spider mites: These tiny pests are difficult to see with the naked eye and cause damage by sucking the sap from the plant. Symptoms of spider mite infestations include yellowing or bronzing of the leaves and fine webbing on the plant. Spider mites can be treated by spraying the plant with insecticidal soap or oil.
Caterpillars: These pests eat the leaves and fruits of the plant, causing extensive damage. Handpicking caterpillars and applying Bacillus thuringiensis (Bt) can help control the infestation. Natural predators such as birds and parasitic wasps also help control caterpillars.
By being aware of these common pests and diseases and taking preventative measures to control them, gardeners can keep Crataegus rotundata Sarg. healthy and thriving.
