also known as nightshades include over 70 different species of flowering plants. These plants contain a large variety of different toxic alkaloids.
Nightshades range from weedy shrubs to small trees. The flowers are five-lobed and are white or purple flowers which form fleshy green berries or fruits which turn yellow or black once matured. The leaves or alternate or opposite, hairy or smooth, and some have prominent spines.
Most horses will not eat nightshade plants unless they are very hungry with no other feed source present. It can however often be found in baled hay, which increases the chances of horses consuming it. Nightshades are still toxic, even in dried form. Nightshades cause gastrointestional tract problems and can affect the horse's central nervous system.
Toxicity is highest in green berries, followed by red or black berries, leaves, stems and roots. It is estimated that one to ten pounds of ingested plant material is fatal for horses.