Red root pig weed and A. palmeri Wats.
Description:
Three foot tall or more, pig weed has alternate, broad lance shaped leaves with toothed margins, apparent veins with the central vein becoming a long leaf stem. Leaves are often red on edges or underneath.
The central stem is much branched, becoming red or red striped as the season progresses with the red continuing into the root.
Flowers are light green, inconspicuous, scaly, spiny, and crammed, forming on short branches packed on the ends of the stems, and in leaf axils. Seeds are tiny shiny ovals.
An annual, it develops a substantial red tap root.
All parts whether fresh or dry may accumulate large quantities of Nitrate, mostly affecting pigs, cattle and sheep.
Symptoms:
Brownish pigment in pink skin, weakness, clumsy, trembling hind limbs, paralysis, abortion in pregnant animals.