Eastern Poison Oak

Rhus toxicodendron

Physical Characteristics

Rhus toxicodendron is a deciduous Shrub growing to 0.6 m (2ft) by 1 m (3ft 3in). See above for USDA hardiness. It is hardy to UK zone 7 and is not frost tender. It is in flower from May to June, and the seeds ripen from September to November. The species is dioecious (individual flowers are either male or female, but only one sex is to be found on any one plant so both male and female plants must be grown if seed is required). and is pollinated by Bees. The plant is not self-fertile. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils, prefers well-drained soil and can grow in nutritionally poor soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It cannot grow in the shade. It prefers dry or moist soil.

Distribution

South-eastern N. America - New Jersey to Delaware, south to Georgia, Alabama and Texas.

Habitats

Woodland Garden Sunny Edge; Dappled Shade; Cultivated Beds;

Edible Uses

Edible Parts: Oil Edible Uses: Oil None known

Medicinal Uses

Antirheumatic Homeopathy Irritant Narcotic Parasiticide Rubefacient Salve Stimulant Poison oak has occasionally been used medicinally, though it is an extremely poisonous plant and great caution should be exercised. Any herbal use should only be undertaken under the supervision of a qualified practitioner. See also the notes above on toxicity. A fluid extract of the fresh leaves is irritant, narcotic, rubefacient and stimulant[4]. It has been used with some success in the treatment of paralysis, obstinate herpatic eruptions, palsy and in various forms of chronic and obstinate eruptive diseases[4]. A mash of the leaves has been used to treat ringworm[213]. An external application has also been used in the treatment of herpes sores[213]. A poultice of the plant has been used to treat infectious sores on the lips[257]. The root has been used to make a poultice and salve in the treatment of chronic sores and swollen glands[257]. A homeopathic remedy is made from the fresh leaves[232]. These should be harvested of a night-time, during damp weather and before the plant flowers[232]. This remedy has a wide range of applications and is one of the main treatments for mumps[232], it is also used in a wide range of skin disorders[4].

Known Hazards

This plant contains toxic substances and skin contact with it can cause severe irritation to some people[11]. The sap is extremely poisonous[11]. The sap contains 3-N pentadecycatechnol. Many people are exceedingly sensitive to this, it causes a severe spreading dermatitis. The toxins only reach the skin if the plant tissues have been damaged, but even indirect contact can cause severe problems[200].