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Naturalisation risk and the vulnerability of many countries to future plant invasions is predicted to increase with human movement and climate change. Unfortunately, the geographical limitation on studies assessing unintentional human‐vectored dispersal (HVD) has hampered progress in understanding its importance, particularly its probability of introducing species that will become naturalised or invasive. The current paper used an explorative approach to determine if human clothing and vehicles disperse species with higher potential to become invasive globally. The study specifically relies on available database of unintentional human‐vectored seed dispersal and recent studies that considered the outcomes of plant species' interaction with humans around the world. The results indicate that human vehicles and clothing contribute to the spread of many extreme risk and most naturalised species of the world. For example, 55% of the 200 most naturalised species have been reported to be dispersed on vehicle while almost one ‐third (32%) have been reported to be dispersed on clothing. Also, of the 235 extreme risk species 41% have been reported to be dispersed on vehicles and 31% on clothing. The results indicate that graminoids, herbs and species with long‐term seed bank are more dispersed via HVD. Conservation managers and practitioners should consider the role of human‐vectored seed dispersal in the spread of invasive weeds, especially in popular and frequently visited areas. Individuals embracing responsible travel practices and adopting proactive measures and protocols to prevent the accidental transport of seeds can significantly enhance our conservation endeavours in our interconnected global ecosystem. [ABSTRACT FROM AUTHOR]

Human-mediated seed dispersal facilitates biological invasions, including the spread of noxious and/or naturalised alien plants in Australia--but which species are dispersed by such mechanisms and what traits do they share? Data were extracted from two reviews of seed dispersed from clothing/personal equipment (e.g. backpacks) and vehicles to assess the range and types of Australian weeds benefiting from these dispersal mechanisms. Across 33 studies, including 11 from Australia, 466 species of weeds in Australia were recorded, 375 from vehicles and 212 from clothing. Many noxious species (17%) and ten Weeds of National Significance were included. Species were predominantly forbs or graminoids with few shrubs or trees. Seeds from annuals were more frequent than expected on vehicles but perennials were more frequent on clothing. New studies will add species to this corpus, but the results already highlight the importance of strategies to minimise risks from such dispersal mechanisms to help reduce the homogenisation of floras, including those in Australia. [ABSTRACT FROM AUTHOR]

Humans can unintentionally disperse plant propagules (herein referred to as seeds) including weed seeds from clothing when hiking. There is limited experimental or observational information, however, about unintended human-mediated seed dispersal, particularly from different types of clothing. We experimentally assessed the probability of seed detaching from socks and trousers along a 5 km standardized route for eight common environmental weeds: B idens pilosa L., C hloris gayana Kunth., C onyza canadensis L., C ynodon dactylon L., D rymaria cordata ( L.) Willd. ex Schult., P oa annua L., P aspalum urvillei Steud. and S porobolus elongatus R. Br. Seed detachment varied among species on both types of clothing, but seeds more easily detached from trousers than socks. When different models were fitted to the data, a three-parameter generalized exponential model with curves provided the best fit. The curves were leptokurtic, with peak close to the seed source and a long flat tail, which indicates that most seeds dispersed from clothing fall close (within 5 m) to the point of attachment with only a small proportion of seeds dispersed over long distances. Combining attachment and detachment data for the same species, we estimated the actual numbers of seeds potentially dispersed over a hike of 5 km. The study indicates that most seeds are likely to be dispersed at the start of walks, although the actual number of seeds will vary depending on several factors such as the behaviour of the hiker and the amount of weed seeds present at the start of the walk. Those few seeds dispersed much further may, however, be more important in terms of plant invasions. Covering socks with gaiters and avoiding walking through weedy areas such as road edges and car parks before starting walks could minimize the risk of seeds attaching to clothing and hence being dispersed. [ABSTRACT FROM AUTHOR]

Weeds are a major threat to biodiversity including in areas of high conservation value. Unfortunately, people may be unintentionally introducing and dispersing weed seeds on their clothing when they visit these areas. To inform the management of these areas, we conducted a systematic quantitative literature review to determine the diversity and characteristics of species with seeds that can attach and be dispersed from clothing. Across 21 studies identified from systematic literature searches on this topic, seeds from 449 species have been recorded on clothing, more than double the diversity found in a previous review. Nearly all of them, 391 species, are listed weeds in one or more countries, with 58 classified as internationally-recognised environmental weeds. When our database was compared with weed lists from different countries and continents we found that clothing can carry the seeds of important regional weeds. A total of 287 of the species are listed as aliens in one or more countries in Europe, 156 are invasive species/noxious weeds in North America, 211 are naturalized alien plants in Australia, 97 are alien species in India, 33 are invasive species in China and 5 are declared weeds/invaders in South Africa. Seeds on the clothing of hikers can be carried to an average distance of 13 km, and where people travel in cars, trains, planes and boats, the seeds on their clothing can be carried much further. Factors that affect this type of seed dispersal include the type of clothing, the type of material the clothing is made from, the number and location of the seeds on plants, and seed traits such as adhesive and attachment structures. With increasing use of protected areas by tourists, including in remote regions, popular protected areas may be at great risk of biological invasions by weeds with seeds carried on clothing. [ABSTRACT FROM AUTHOR]