By Meaghan Anderson
As corn and soybean are taken out of fields, some fields may reveal an unexpected mat of Asian copperleaf lurking below the canopy. As of this summer, we’ve identified Asian copperleaf (Acalypha australis) in crop fields in eight counties: Calhoun, Humboldt, Boone, Wright, Franklin, Hardin, Grundy, and Black Hawk. Early identification of this species is key to adopting effective management tactics to reduce its spread to other fields.
Asian copperleaf is in the spurge family but lacks the milky sap produced by many spurges. At maturity, the plant has alternate leaves that are 2-4 inches long, lanceolate to egg-shaped, with fine, blunt teeth and deep veins (Figure 1). Plants can reach heights of 2-3 ft., though may be smaller if under a crop canopy. Plants that receive more sunlight are highly branched, while those under the canopy have few branches (Figure 2).
This species is often found under the crop canopy at harvest time (Figure 3). As fall approaches, the upper leaves on plants may develop a reddish or coppery color (Figure 4). Unlike waterhemp, Asian copperleaf does not have long flowerheads/inflorescences at the tops of stems, instead producing flowers and seed primarily along stems.