Amaranthus spinosus aka Spiny Amaranth and Amaranthus viridis aka Green Amaranth are both an annoying weed in the southeastern US. Both are called Pigweed.
My family have been trying to eradicate both from our gardens for 50 years that I know about. Green amaranth is just annoying, it sucks up water and nutrients from veggies that are far more nutritious. Both plants will reach 4ft in height.
Spiny amaranth does the same damage as green but has another far more hazardous trait. When I was a kid it was called “step light”. It has tiny thorns, those little nodule/bundles can be seen in the photo. As kids we’d go barefoot all summer even when working in the garden etc.
Those tiny thorns would easily embed themselves in our feet, extremely painful… causes us to “step light”. An adult would have to stop what they were doing, pull out a needle and magnifying glass to dig them out of our feet… The tiny thorns will also embed themselves in your hands if you accidentally grab the stalk.
You can see the seed heads of the plant in the foreground with the red stalks… Those seed heads are embedded with those tiny thorns…. Do you really want this in your garden?
I’d recommend being very careful about the species of amaranth seeds you buy.
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