The effects of weed management systems on density (A) and dry mass (B) of weeds in the black cumin field in two cropping years. The values represent the means of 2017 and 2018. WF: weed free plot; WI: weed infest plot; HCt1: H. vulgare living mulch, mowing after black cumin establishment; HCt2: H. vulgare living mulch, mowing before the black cumin flowering stage. TCt1; T. alexandrinum living mulch, mowing after black cumin establishment; TCt2: T. alexandrinum living mulch, mowing before the black cumin flowering stage.