Can field botany be effectively taught as a distance course? Experiences and reflections from the COVID-19 pandemic.

The COVID-19 pandemic that started in 2020 forced a rapid change in university teaching, with large numbers of courses switching to distance learning with very little time for preparation. Courses involving many practical elements and field excursions required particular care if students were to fulfil planned learning outcomes. Here, we present our experiences in teaching field botany in 2020 and 2021. Using a range of methods and tools to introduce students to the subject, promote self-learning and reflection and give rapid and regular feedback, we were able to produce a course that allowed students to achieve the intended learning outcomes and that obtained similarly positive student evaluations to previous years. The course and its outcomes were further improved in 2021. We describe how we structured field botany as a distance course in order that we could give the best possible learning experience for the students. Finally, we reflect on how digital tools can aid teaching such subjects in the future, in a world where public knowledge of natural history is declining.

The seed dimorphism of Spergularia marina in relation to dispersal by wind and water.

The seeds of the halophyte Spergularia marina differ both within and between individuals in that they either possess or lack a membranaceous border. This paper presents a morphological study of the length, weight and area of the seed types, and their dispersal characteristics under experimental conditions of wind and water dispersal. The winged seeds are shown to be larger both by length and by weight. Their rate of descent increases with wing loading. If the wing is lacking, however, the rate of descent increases with weight only. The distance of dispersal is equal for both seed types except at low wind speeds, when the winged seeds disperse farther. If the seed wing is removed, the excised seeds have shorter dispersal distances. When dispersed by water, a difference in the distance seeds are dispersed can only be detected in the presence of vegetation. The winged seeds are more frequently trapped in the vegetation as compared to the unwinged seeds. The hypothesis that the seed dimorphism is an adaptation for differential dispersal distances is discussed.