RHUs

Rhus is a genus of flowering plants in the cashew family, Anacardiaceae, commonly known as sumacs. The genus comprises several dozen species of deciduous shrubs and small trees native to Asia, Africa, Europe, and the Americas. Rhus species range from spreading groundcovers to tall, bushy forms, and some have spiny branches.

Leaves are typically pinnate with 9–31 leaflets, margins serrate, and often scented when crushed. In late summer to fall, many species produce dense inflorescences of small flowers, followed by clusters of red to purplish drupes that attract birds. Fruit ripening and bright foliage give many Rhus species ornamental value, particularly Rhus typhina (staghorn sumac) and Rhus glabra (smooth sumac).

A notable edible species is Rhus coriaria, the Sicilian sumac, whose dried berry fruits are ground into a tart red spice used in Middle Eastern and Mediterranean cuisines. Some species are grown or escape cultivation for landscaping due to drought tolerance and rapid growth.

Ecology and cultivation: Rhus is adaptable to a range of well-drained soils and sunny locations. Birds disperse the berries. In horticulture, sumacs are valued for autumn foliage color and hardiness, though some forms can be aggressive outside their native range.

Toxicology and taxonomy: As with many members of the Anacardiaceae, handling plant sap from certain species may cause skin irritation in sensitive individuals. The genus has undergone taxonomic changes, with some species formerly placed in Rhus now assigned to Toxicodendron. Rhus coriaria remains the principal culinary sumac.