Bärbel Gerowitt

1 INTRODUCTION The biodiversity of weeds on conventionally cultivated fields has decreased over the last decades.1-4 Preserving and promoting weed diversity is desirable because weeds provide regulating ecosystem services in the agro-ecosystem.5 In conventional farming, herbicides play a key role in controlling weeds.

1. Introduction Considered one of the world’s worst weeds [1,2], the creeping perennial species Cirsium arvense (L.) Scop (Creeping thistle) grows in spatially distinct patches of varying sizes [3]. Commonly, C. arvense field infestations are patchy, with dense thistle stands alternating with areas free of thistles [4,5]. The clonal root system of creeping thistles facilitates survival and spatial spread in arable fields through vegetative sprouting.