09/05/2025
Toxic Plants of Central Oregon
Second Installment
Kayla Jensen, DVM
Bittersweet Nightshade & Hairy Nightshade
Identification:
Bittersweet Nightshade: Vine or shrub usually 3-6 ft tall, small 5-petal purple flowers, berries grow on the plant and range from green to red based on ripeness (about the size of a blueberry).
Hairy Nightshade: bushier plant that grow to about 3ft tall, small 5-petal white flowers, conspicuous “fuzz” cover leaves and stems, green to dark brown shiny berries depending on ripeness
Location: Found in thickets, pond or irrigation margins, low woods, fence lines, or roadsides.
Toxicity Concern: Low, the plant is bitter and animals will avoid it unless there are no other grasses to graze or it is dried and contaminating hay. All parts of the plant are toxic, but the level of toxicity is variable between plants based on environment and season. Usually they are more toxic in the autumn. Animals rarely consume enough of the plant to become intoxicated.
Toxin: Atropine is the toxin found in nightshades and has several reversible effects on the central nervous system.
Signs: Fever, high heart rate, dark-colored gums, salivation, dilated pupils, tremors, colic, abnormal movements or behaviors, or sometimes death.
Treatment: Supportive care is often necessary. If it is known that the horse ingested nightshade, an antidote called neostigmine may be given. However, definitive diagnosis of intoxication is rarely able to be made. Fortunately, most animals recover.
Prognosis: Fair to Good. Supportive care may be necessary, but most animals recover in 1-2 days.
W**d Control Strategies: Hand-pull the w**ds ensuring you get the roots. Recheck the contaminated area after several months and hand-pull any of the young plants remaining.