Amaranthus bouchonii Thell. (Franse amarant) en A. hybridus L. (Groene amarant) in Nederland

Amaranthus bouchonii Thell. was first recorded in the Netherlands in 1947. Since then it has been found in some ports and industrial areas, and in 1983 it naturalised along the river Waal. Its indehiscent fruits differ distinctly from those of A. hybridus L. which are dehiscent. Minor, but constant differences occur in the length of the tepals and the bracteoles. Amaranthus hybridus was first found in the Netherlands in 1829. Now it occurs in the southern part of the country as a rather common alien in dynamic areas: ports, industrial areas, arable fields, rubish tips and river banks. The Dutch collections of A. hybridus s.l. are, though variable, homogeneous in plant colour, size, seed colour, and shape of styles. In particular, we found the length of the largest bracteole useless in separating taxa. Amaranthus hybridus applies to these collections.