Field Guide 
Weed Management Horse-Nettle
Horse-Nettle (Solanum carolinense L.)
Crop Impacts: Hay and pastures
About Horsenettle:
Horsenettle is a perennial broadleaf plant that reproduces via the germination of seeds and by their underground rhizomes system. It can be found throughout North America and produces poisonous berries.
Family: Nightshade or Potato Family (Solanaceae)
Horse-nettle Scouting and Prevention:
Horsenettle has an erect stem that stands about 60 to 100 cm tall with a few branches that are covered with tiny hairs at the top of the plant. All branches and stems are sharp, hard and have 5 mm long spikes. The leaves on the Horsenettle alternate one another and have 2 to 5 shallow to deep lobed or sharp-points on each side of the leaf. These leaves are covered with small hairs and more spikes that go up the underside of the main vein. Horsenettle also produces white to pale purple flowers with yellow anthers that bloom between July and autumn. They can be found at the upper parts of the plant on the sides and ends of the branches. The berries Horse-nettle produces are originally green and turn yellow as the plant matures.
Common locations
- - Sandy soil
- - Grain fields
- - Pastures
Horsenettle Control:
Cultural Control
The best way to culturally control Horsenettle is by mowing it every 30 days during the warmer months. The best time to mow this weed is as soon as it blooms, which is about 30 days after the shoot of the plant starts to show. Continually cutting off the regrowth during harvest season will start to weaken the roots, making them vulnerable to the application of herbicides.
Chemical Control
In the fall after the interval mowing, treat re-growth with systemic herbicides. Systemic herbicide applied to mature Horsenettle in the late summer to fall is the most effective form of treatment. After the chemical treatment, the grass cannot be mowed for a minimum of 2 weeks to make sure the herbicide goes all the way through the weed. If you apply herbicide during the fall it must be applied 2 weeks before the first frost. A few herbicides that have been known to take control of Horsenettle: Chaparral, Grazon P+D, GrazonNext, Milestone, Surmount.
Latin / Alternative Horsenettle names:
- - Solanum carolinense L.,
- - Morelle de la Caroline
- - Ortie de la Caroline
Additional Horsenettle Resources
http://www.omafra.gov.on.ca/english/crops/facts/ontweeds/horse_nettle.htm
http://www.thehorse.com/articles/26137/weed-of-the-month-horsenettle