Carolina nightshade also known as horsenettle (Solanum carolinense) is a common perennial weed, native to the southern United States. It has conspicuous sharp spines on the leaves and stems and the leaves emit a potato odor when crushed. S. carolinense blossoms from May until September, with star-shaped clusters of flowers appearing thirty days after the plants emerge. It produces tiny green berries which look like miniature tomatoes. The berries turn yellow when ripe and become wrinkled after drying. Inside the fruit, a foul-smelling pulp surrounds numerous flat, round, yellow seeds 1/16 to 1/8 inch (1.5 to 3 mm) across. The average number of seeds per fruit is about 85, and one plant may produce as many as 100 fruits.
S. carolinense is poisonous to poultry in fresh or dried form, as it contains highly toxic alkaloids, the most meaningful being solanine. Solanine is a glycoalkaloid that affects the bird's central nervous system and gastrointestinal tract. Birds generally won't eat S. carolinense unless they have nothing else to eat.
- slow breathing
Systemic herbicides are effective against horsenettle and should be applied to mature plants in late summer or fall. After herbicide treatment, horsenettle should not be mowed for at least two weeks—the time required to translocate the chemicals into the roots. Similarly, fall herbicides should be applied at least two weeks before expected frost.
Mowing at thirty-day intervals. The best time for the first mowing is right after horsenettle has come into full bloom, about thirty days after shoot emergence Root reserves are at their lowest right after flowering, and forcing the plant to produce new top growth will further deplete its energy reserves. Continually cutting off the top growth during regular hay harvest will weaken the root system, making it more vulnerable to herbicides. Rotating an infested field into grass or clover hay for one year allows this combination of treatments.
- G Damerow The Chicken Health Handbook Storey Publishing (2015)
- Keeler, R. F.; Baker, d. C.; Gaffield, W. Teratogenic Solanum species and the responsible teratogens. Keeler RF, Tu TT (eds.) Handbook of natural toxins. (1991)
- Gaffield, W.; Keeler, R. F.; Baker, D. C. Solanum glycoalkaloids: Plant toxins possessing disparate physiologically active structural entities. Keeler RF, Tu TT (eds.) Handbook of natural toxins. (1991)
- Case, A. A. Nightshade poisoning. Southwestern Vet, 9 140-143 (1955)