Celestine A. Duncan1, Weed Management Services and Mark J. Renz, New Mexico State University
Hoary cress (Cardaria sp.) is also known as whitetop or little whitetop. It is a deep-rooted, creeping perennial mustard that spreads by seed and vegetative root growth. There are three species including lens-podded hoary cress (C. chalapensis), heart-podded hoary cress (C. draba); and globe-podded hoary cress (C. pubescens). Hoary cress is well adapted to moist sites including sub-irrigated and irrigated pastures and hay-fields, rangeland, and disturbed sites such as roadsides, railways, and ditch banks. It can also invade cropland including small grain and alfalfa fields. Hoary cress may reduce crop yields, displace native plants, and reduce biodiversity, wildlife habitat, and forage production. The weed contains glucosinolates that can be toxic to cattle (McInnis et al. 1993). Hoary cress begins growth early in spring from a rhizomatous root system and flowers by April or early May. Seeds are produced about a month after flowering.
Tags: Hoary Cress, Whitetop