(Des Moines, IA) -- A weed first spotted in an Iowa farm field years ago, has been found again. The Iowa Department of Agriculture is asking farmers to report any sightings of Asian copperleaf. It was first detected in a cornfield in Cedar Falls in 2016. Before that, the only documented infestation in North America was in New York City. The most recent sighting was in a Grundy County soybean field. Officials say it appears to have been there for several years before being identified. Both were spotted during harvest activity.
Asian copperleaf (Acalypha australis) is native to China, Australia, Japan, and other countries in the region. It is unknown how the plant was introduced to Iowa, but it is likely the two reported infestations are related. The plant is a threat to row crops in its native range.
Asian copperleaf is in the spurge family but lacks milky sap common in many spurges. It is an erect plant that can reach heights of 2-3 ft, but most plants found in Iowa were less than 18” in height. Leaves are 2-3” long, lanceolate with serrated (finely toothed) edges. The distinguishing characteristic of Asian copperleaf are the bracts located beneath the flowers. The bracts are circular to heart-shaped with a dentate margin. Virginia copperleaf and three-seeded mercury, two other Acalypha species present in Iowa with a similar growth habit, have deeply-lobed bracts. It is unlikely that anyone could confidently differentiate between these species prior to flowering. Asian copperleaf seems to emerge late in the season and remains under the crop canopy throughout the growing season.
Farmers are asked to report sightings to help determine how widespread the weed is across the state, and the risk it poses to Iowa crop production.
If you detect the plant, please contact the Iowa Department of Agriculture and Land Stewardship at 515-725-1470 or e-mail firstname.lastname@example.org.