## 1 Introduction  
Invasive alien plant species (IAPS) are non-native plants that are a consequence of human activities and cause problems on a worldwide scale [1, 2]. They significantly impact ecosystems from the local to landscape scale [3, 4, 5], and they also have a socio-economic influence on human well-being [6]. The costs associated with the control and containment of already established IAPS are very high [7, 8]. Prevention, increased awareness, and rapid responses are essential for avoiding further spread of these species [9]. Engaging citizens to help with early detection may be highly useful [5, 9]. In this case, ecologists and the community both work towards the same goal by obtaining information about the location of IAPS [5, 10]. At the same time, the citizens improve their ecological knowledge, increase their ecological awareness, and foster a sense of community affiliation [11, 12, 13]. The APPLAUSE project, an abbreviation for Alien Plant Species from Harmful to Useful with Citizens' Led Activities, explored the potential utilisation of invasive alien plant species in the creation of different products within a circular economy framework [14]. As part of this initiative, seven of these species were used in a trial about paper production, including varieties such as Japanese knotowed, giant goldenrod, and black locust [15]. Japanese knotowed (_Fallopia japonica_) is an extensively distributed invasive alien plant species (IAPS) found across Europe and North America [16]. It is recognisable by its abundant green foliage, dense yearly stems, and a rhizome crown located at the base of the plant [8; 17]. It is a fast-growing competitor that adapts its growth very well to different environmental conditions [8]. Despite being invasive, it can have a positive impact on ecosystems. The plant can also be used as a source of food, dyes [16; 17], or cellulose fibres. Giant goldenrod (_Solidago canadensis_) is widely spread in North America. From there, it was introduced to Europe and Asia. It has a high growth rate due to its ability to spread via rhizomes, production of a considerable number of wind-borne seeds that germinate on a wide range of different soils, and allebotathic interactions which inhibit the growth of seedlings of other species [18; 19; 20]. Black locust (_Robinia pseudoacacia_) is an invasive species in Europe which also originates from North America. Considered as one of the most commonly planted woody species, it is used as an ornamental tree, for the production of different types of timber, as firewood, as bees' nectar sources, and to control erosion [21; 22; 23]. It threatens natural habitats by reducing local biodiversity [24]. Some studies have reported [25; 26] about the adequate strength properties of papers made from different fast-growing annual plant species. It was determined that enhancing the fibre processing and paper-making procedures is essential for achieving optimal printability. This involves increasing whiteness through elemental chlorine-free (ECF) delignification [27] and reducing roughness, often achieved through calendering [28]. Additionally, paper coating further enhances print quality [29]. The aim of our research was hence to investigate the usability of paper with fibres from Japanese knotowed, giant goldenrod, and black locust which can serve as printing substrates. The inkjet printing technology is well adapted to current trends in digital printing that have gained importance in recent years. The main advantages of the inkjet technology are low costs and reliability [30]. Therefore, these printing technologies are widely used in the home environment as well as for printing documents intended for storage. When interpreting symbols into meaningful content, whether on paper or a screen, the ease of this process defines legibility [31]. Various studies emphasise the significance of legibility, which is essentially a facet of usability [32; 33; 34; 35]. Legibility is, to a certain extent, associated with the characteristics of the substrate.