and groundwater while phytoextraction aims to accumulate metals in the aerial part of the plants which makes it possible to reduce their quantity in the soil [4]. Many plants accumulate different levels of Se in their tissues, ranging from less than 50 mg/kg of dry matter for non-accumulators to 100-1000 mg/kg dry matter for hyper-accumulators [5]. Some members of the Brassicaceae family, such as Indian mustard (_Brassica juncea_ [PERSON]), and canola (_Brassica napus_ cv. [PERSON]), are known as phytoaccumulators, while some other members are known as Se volatilizers, such as cabbage (_Brassica oleracea_ var. capitata), broccoli (_Brassica oleracea_ var. botrytis cv. Green Valiant), cauliflower (_Brassica oleracea_ var. cauliflora), and Chinese mustards (_Brassica juncea_ Czern. L. and _B. campestris_ var. chinesis), next to rice (_Oryza sativa_ L.), hybrid poplars (_Populus tremula_ H alba L.), alfalfa (_Medicago sativa_ L.), and vetiver (_Vettieria zizanioides_ L.)) [6]. The mechanisms and soil parameters controlling Se availability and plant uptake are still not well understood [7]. Moreover, to increase the efficiency of soil bioremediation, phytostabilization has been effectively used to immobilize metalloids and govern their bioavailability and biotransformation in contaminated soils [8; 9]. Indeed, biochar increases soil pH and fertility; enhances water-holding capacity, nutrients, and microbial activity in the soil [10]; and increases agricultural yields by enhancing germination rate, root length, and plant growth. Hence, biochar reduces plant-available metalloids, and increases the microbial biomass that reduces the phytotoxicity of metalloids in soils, which consequently promotes revegetation. However, the efficiency of biochar's adsorption depends on its characteristics, mainly its surface properties, microporous structure, specific surface area with various functional groups, and high ion exchange capacity, which are influenced by the type of feedstock and the different pyro-gasification systems [11; 12; 13; 14; 15; 16]. Biochar can immobilize heavy metals in soil, and effectively reduce their concentration in the edible parts of plants [3]. Thus, phytoremediation and biochar were widely combined for available heavy metal immobilization (by biochar) and the removal of the remaining available fraction by phytoextraction. Selenium mobility in the soil depends on redox potential in soil and higher oxidation states [17]. Nevertheless, in the presence of biochar, Se may be reduced to a less mobile species due to interaction with oxygen-containing functional groups on the surface of biochar [18]. Furthermore, the extraction of Se by plant accumulators is improved by adsorbing competing nutrients with the biochar, favoring metal uptake by plants [19]. Indeed, biochar with positive charges can retain anionic metalloids such as selenite and selenate which are weakly adsorbed by the negatively charged soil particles [20]. To the best of our knowledge, no work was set to investigate the phytoremediation potential of the native plants of North America like _Phleun_ sp., a grass belonging to the Poaceae family, which has adapted to the cold climate of northern Quebec. These plants have a fast growth and development rate, high biomass, and tolerance to high Se levels. Due to the lack of previous research on finding a solution for Se remediation in a cold climate, this work aimed to test the potential of activated biochar in combination with phytoextraction in contaminated soil in a Nordic context. The specific objectives were as follows: (1) to assess the effect of pristine and activated biochar addition on Se mobility in soil; (2) to identify their effect on soil characteristics; (3) to investigate the effects of the addition of biochar materials on Se uptake from soil and the phytoextraction potential.