Pigweed is the common name for Amaranthus retroflexus.
It is an annual herb with an erect form (there is also a prostrate form), sometimes reaching approximately 10 feet (3m) in height.
Leaves higher on the stem can be around 6 inches (15cm) in length and have a lance like shape, while those lower down the stem have an oval or diamond shape.
Additional Information About Pigweed
It is native to tropical America and is now one of the most common pasture weeds in the United States, thriving in any disturbed soil. It derives its name from traditionally being used as fodder for pigs and for its tendency to thrive in disturbed soil where pigs are pastured.
The weed is now also commonly found Asia, Africa and Europe and is used as a food source for animals and as a vegetable for humans.
Pigweed As A Human Food Source
No species of Amaranthus is known to be poisonous, but like many leafy vegetables, the leaves can contain high levels of oxalic acid when raw. When grown in nitrate-rich soils, the leaves may also contain high levels of nitrates which requires discarding the water used for boiling the leaves.
It has a long cultural history of medicinal and culinary use amongst Native American groups and can be ubiquitously found in Mexican markets as Quelite quintonil.
The seeds from Amaranthus are edible and are used raw or cooked, and can be ground into flour for baking into bread, used as a thickener or as hot cereal.
What To Do With Pigweed In The Garden
Pull it out, pick some of the young top leaves off and treat them like you would spinach. If you have some chickens, throw it to them as they love it.