Taxonomic name: Euryops multifidus (Thunb.) DC.
Synonyms: Othonna multifida Thunb.
Common names: euryops, hawk's eye, sweet resinbush
Organism type: shrub
Euryops multifidus commonly known as sweet resin bush, is a medium-sized shrub. When the shrub blooms in late winter to early spring, hundreds of small, yellow, daisy-like inflorescences nearly hide the bright-green foliage. It is found in semi-arid grasslands and can readily establish in the midst of vigorous existing grassland vegetation. E. multifidus's spread causes dramatic changes in native ecosystems. As the plants grow and spread, they exclude nearly all species of native grasses and shrubs, forming a monoculture. There is little available information regarding the management of this species, but the USDA Forest Service is currently researching methods of control.
Euryops multifidus is described as a medium-sized shrub (usually less than 0.9m tall). It has small leaves (2.5cm long), each leaf is divided into three to five narrow lobes, which look like the tracks of tiny turkeys. The shrub is usually in leaf throughout the winter and spring, and sheds its leaves during dry seasons. E. multifidus belongs to the sunflower family (Asteracae). When the shrub blooms in late winter to early spring, hundreds of small, yellow, daisy-like inflorescences nearly hide the bright-green foliage. The name 'sweet resinbush' comes from the sweet, but disagreeable odor of the flowers and the drops of resin exuded by the woody stems (USDA-Forest Service, Undated).
Euryops multifidus grows on hillsides and mesas in the semiarid grasslands (Van Auken, 2000). Seedlings of E. multifidus readily establish in the midst of vigorous existing grassland vegetation (USDA-Forest Service, Undated).
Euryops multifidus is not eaten by domestic or native herbivores. It grows on hillsides and mesas in the semiarid grasslands, and native grasses and woody plants have disappeared from areas where it is found (Van Auken, 2000). The USDA-Forest Service (Undated) states that, "E. multifidus's spread causes dramatic changes in native ecosystems. As the plants grow and spread, they exclude nearly all species of native grasses and shrubs, forming a monoculture. Once established, the populations persist because young plants readily grow beneath canopies of older plants." The authors go on to state that, "E. multifidus is becoming an environmental bulldozer, slowly and inexorably killing off all other vegetation-food for both wildlife and livestock-as it expands its territory."
Native range: Africa (USDA-GRIN, 2003)
Known introduced range: North America (USDA-NRCS, 2002)
Introduction pathways to new locations
Landscape/fauna "improvement": The USDA-Forest Service (UNDATED) states that E. multifidus was introduced into the United States in the 1930s by USDA researchers and the Civilian Conservation Corps, in an effort to re-vegetate rangelands that was based on an erroneous observation that this species was readily eaten by livestock.
Local dispersal methods
On animals: Schalau (2001) reports that, "Fruits are covered with fine "hairs" that allow them to cling to animal fur and clothing. This creates a great potential for seed transport and establishment of new populations."
Integrated management: Littlefield (2002) reports that, plant biologists at the Santa Rita Experimental Range in southeastern Arizona, are researching various eradication and management techniques. Control methods include mechanical removal along with application of an herbicide, followed by careful monitoring for new sweet resin bush plants and hopefully, reestablishment of native plants."
Schalau (2001) states that, "In 1999, the Forest Service tried to burn the E. multifidus population. The burn was not successful due to the lack of fuels to carry the fire. The proposed action for 2000 is to use an Integrated Vegetation Management (IVM) approach. IVM uses a variety of techniques to increase control success. Mowing would be used to reduce plant size. Mowing would be followed by hand spraying of herbicide and hand digging. Mowing would also stress the plants and reduce the quantity of herbicide required to kill the plants. The herbicides they propose using would have negligible effects on non-target plants and animals."
Euryops multifidus flowers produce an abundant seed crop by April or May. The seeds form in star-like clusters of about ten fruits. Most of the seeds drop to the ground around the parent plant, seedlings are found near and around established plants. Fruit are covered with fine "hair" that allow them to cling to animal fur and clothing. This creates a great potential for seed transport and establishment of new populations (Schalau, 2001).
Reviewed by: Larry Howery, Range Management Specialist, School of Natural Resources The University of Arizona Tucson USA
Compiled by: National Biological Information Infrastructure (NBII) & IUCN/SSC Invasive Species Specialist Group (ISSG)
Last Modified: Thursday, 14 April 2005