Overview:
Rhus aromatica Ait. var. illinoensis (Greene) Rehd., commonly known as Fragrant Sumac, is a native deciduous shrub that belongs to the Anacardiaceae family. It can be found in various states in the United States, including Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, Ohio, Wisconsin, and Wyoming.
Common Names:
Fragrant Sumac is also known by other common names, including Aromatic Sumac, Polecat Bush, Skunkbush Sumac, Lemon Sumac, and Squawbush.
Appearance:
The shrub typically grows up to 2-6 feet tall, with an equal spread, and prefers well-drained soils. Its leaves are trifoliate, coarsely toothed, and can vary in shape, ranging from oblong to oval. In the fall season, the leaves turn brilliant shades of red, orange, and yellow. The stems and branches of the plant are covered with fine hairs, and the bark is brownish-gray in color. The shrub also produces small yellow flowers and red berries during the summer months.
Uses:
Every part of the Fragrant Sumac has been historically used for various purposes. The leaves and fruit have been used for medicinal purposes, including for treating cold and fever symptoms, as well as for their astringent and diuretic properties. The plant is also used in landscaping and horticulture, as it is drought-tolerant, easy to grow, and provides a beautiful burst of color in the fall. Additionally, its berries are a source of food for various wildlife, including birds, deer, and bears.
Light Requirements
Rhus aromatica Ait. var. illinoensis prefers full sun but can tolerate partial shade. It requires at least 6 hours of direct sunlight to produce flowers and fruit. In shady conditions, its growth may be stunted, and leaf production can be reduced.
Temperature Requirements
This plant species is well adapted to the harsh conditions of the Midwest. It can tolerate a wide range of temperatures, including extreme heat and cold. The optimal temperature range for growth is between 60 and 85 degrees Fahrenheit, but it can tolerate temperatures below freezing. However, young plants may need protection from frost in the early stages of growth.
Soil Requirements
Rhus aromatica Ait. var. illinoensis prefers well-draining soil that is slightly acidic to neutral. It can tolerate poor soil conditions and drought but requires adequate moisture to thrive. Avoid planting this species in areas with standing water or where the soil is constantly wet. Adding organic matter such as compost to the soil can improve its water-holding capacity and nutrient content.
Cultivation
Rhus aromatica Ait. var. illinoensis (Greene) Rehd. is an understory shrub that can tolerate a variety of soil types and pH levels. It prefers well-draining soils and can be grown in full sun to partial shade. This plant is also tolerant of drought and can withstand occasional flooding. It is hardy in USDA zones 3-9.
Watering Needs
This plant requires moderate watering during its growing season, which is typically from late spring to early fall. Avoid overwatering as it may lead to root rot. During drought conditions, it is recommended to provide supplemental watering to ensure the plant's survival.
Fertilization
Rhus aromatica Ait. var. illinoensis (Greene) Rehd. typically does not require fertilization as it can fix nitrogen in the soil. However, if the plant appears to be struggling, a balanced slow-release fertilizer can be applied in the spring.
Pruning
Pruning of Rhus aromatica Ait. var. illinoensis (Greene) Rehd. is best done in late winter to early spring. This plant can be pruned to maintain a desired shape or to remove any damaged or diseased branches. It is important to wear gloves when pruning as the plant's sap can cause skin irritation.
Propagation of Rhus aromatica Ait. var. illinoensis (Greene) Rehd.
Rhus aromatica Ait. var. illinoensis (Greene) Rehd. can be propagated by several methods, including:
Seed Propagation
Propagation from seed is the most common method of reproducing Rhus aromatica Ait. var. illinoensis (Greene) Rehd. This method can be done either by sowing directly into the ground or in containers. The seeds should be planted in the fall before the first frost. Before sowing, the seeds should be stratified in a cold, moist place for several weeks to simulate winter conditions. Germination should occur in the spring.
Cuttings Propagation
Rhus aromatica Ait. var. illinoensis (Greene) Rehd. can be propagated by cuttings, but this method can be more difficult and not as successful as seed propagation. Cuttings should be taken in late spring and early summer when the plant is actively growing. The cuttings should be about 4-6 inches long with several nodes. The bottom 1-2 inches of the cutting should be stripped of leaves and dipped in rooting hormone. The cutting should be planted in a well-draining soil mixture and kept moist until roots develop.
Layering Propagation
Another propagation method for Rhus aromatica Ait. var. illinoensis (Greene) Rehd. is layering. This method involves bending a low-lying branch to the ground and covering it with soil. The branch should be wounded slightly before being covered to encourage root growth. The branch should be secured in place with a stake or rock. After several weeks, roots should develop, and the new plant can be separated from the mother plant and transplanted to a new location.
Disease and Pest Management for Rhus aromatica Ait. var. illinoensis
Rhus aromatica Ait. var. illinoensis, commonly known as the fragrant sumac, is a deciduous shrub that belongs to the Anacardiaceae family. It is native to North America and is often grown as an ornamental plant. However, like all plants, it is susceptible to diseases and pests that can cause havoc to its growth and ultimate survival.
Common Diseases
One of the most common diseases that affect the fragrant sumac is the leaf spot disease. This disease is caused by a variety of fungal pathogens, including Phyllosticta minima, Pestalotiopsis fungal sp, and Cryptocline cyclaminis, among others. The disease presents as a series of small, dark brown to black, circular spots on the leaves. The affected leaves eventually yellow, drop, and leave the plant looking sparse and unsightly.
Another common disease that affects the fragrant sumac is powdery mildew. This disease is caused by the fungal organism Erysiphe sp. and manifests as a whitish-grey powder on the leaves, stems, and flowers of the plant. The powdery mildew can cause a deformed and dwarfed growth.
Common Pests
The fragrant sumac is susceptible to attack by a variety of insect pests, including spider mites, lace bugs, and bagworms. Spider mites feed by sucking sap from the leaves, leading to a yellowing of the leaves and the appearance of unsightly webs. Lace bugs, on the other hand, cause a yellowed or stippled appearance on the leaves, and the leaves may fall off prematurely. Bagworms cause the skeletonization of the leaves and may lead to complete defoliation if left unchecked.
Ways to Manage Diseases and Pests
To manage leaf spot disease, remove and destroy all infected leaves as soon as you notice them. Avoid overhead watering to prevent the spread of spores. Applying fungicides may also be effective in controlling the disease. To manage powdery mildew, improve air circulation around the plant by pruning and spacing plants properly. Applying a fungicide may also be effective.
To manage insect pests, prune and dispose of infested plant parts as soon as you notice them. Applying insecticide may also be effective, but be sure to follow the manufacturer's instructions and use it as a last resort. Encourage the presence of natural predators, such as ladybugs, lacewings, and praying mantis, by planting their preferred food sources.
By taking proactive measures to manage diseases and pests, you can ensure that your fragrant sumac thrives and remains an attractive addition to your garden or landscape.
