Ground cover species selection to manage common ragweed (Ambrosia artemisiifolia L.) in roadside edge of highway
Bae, J., Byun, C., Watson, A.K., Benoit, D.L. (2015). Ground cover species selection to manage common ragweed (Ambrosia artemisiifolia L.) in roadside edge of highway. Plant Ecology, [online] 216(2), 263-271. http://dx.doi.org/10.1007/s11258-014-0433-9
In southern Quebec, Canada, Trifolium species are commonly used as supplement ground cover along roadside of major roads to assist turf recruitment. They often fail to establish particularly near roadside edges. The noxious weed, Ambrosia artemisiifolia, exploits the empty niches. Based on an assumption that heavy metal stress mainly drives plant species shift, we conducted a field experiment to test the emergence of four species near roadside edges along a metal gradient. The test species included a clover ground cover (Trifolium arvense), two candidate ground covers (Lotus corniculatus and Coronilla varia), and the weed (A. artemisiifolia). Two hundred wet-cold stratified seeds of each species were sown in plots (20 × 30 cm), assigned separately for one of four species treatments, replicated three times. We measured final emergence percentage and soil metal contents and analyzed their correlations. T. arvense emergence was negatively correlated with Zn, Pb, and Cu. In contrast, A. artemisiifolia emergence was positively correlated with Zn, Pb, and Cu. The experiment supports the hypothesis that A. artemisiifolia colonization along roadside edges may be attributing to its greater tolerance for Zn, Pb, and Cu than T. arvense. In evaluating the two legume candidates, L. corniculatus was positively correlated with Zn, Pb, and Cu like A. artemisiifolia, while C. varia emergence did not have significant relationship with Pb and Cu. The current finding implies that L. corniculatus can be a good candidate because of its emergence performance and its tolerance to heavy metal, similarly to that of A. artemisiifolia.