Q: This weed grows in a semi-shaded, wooded area in my backyard, reaching 12 inches or more in height. The root system forms a rather shallow mat off the main tap root. It has pale purple flowers. The fruit is a globe approximately 1/2-inch in diameter, and has light green and dark green streaks, similar to the pattern on a watermelon. Needles are on the stems of the plant, the leaf stems and the larger veins of the leaves, both top and bottom.
I am not real keen on the plant but the needles are the killer. They will punch through a thick leather glove and let you know they are there.
A: If I am not mistaken, this plant caused me to say my first curse word as a youngster. Carolina horsenettle, Solanum carolinense, infested my family’s pastures and I loved to run barefoot through the grass. As you’ve noted, sharp spines occur throughout the plant.
As I discovered when I was younger, even the seedlings have sharp needles. I’d limp home to have my dad remove the spines with tweezers.
Horsenettle is a perennial plant, coming up from the roots each year. The most permanent solution is to shove a trowel under it and heave the whole thing out of the dirt. Carefully pick it up and pitch it in the trash. Herbicides like glyphosate (Roundup, etc) and 2,4-D (Weed B Gon, etc) will kill the top but it takes a couple of applications to obliterate the plant for good.
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