Table 1. Schematic outline of the crop sequence arrangements sampled in the Säby long-term experiment near Uppsala, Sweden (R4–0009)²⁰.

Year	2011			2012			2013			2014
Time of year1	I	II	III	I	II	III	I	II	III	I	II
Wheat monocult.	W	W	W	W	W	W	W	W	W	W	W
CP Flax	W	W	F	F	F	W	W	W	R	R	R
CP Rapeseed	F	F	W	W	W	R	R	R	W	W	W
CP Ley	B	B	L2	L	L	L	L	L	W	W	W

Sampling of plant material was done only in wheat (W, bold dark letters). The light letters indicate the here not sampled crops of the crop sequences, including the preceding crops (C_P) flax (F), rapeseed (R), ley (L) and additionally also barley (B) in the C_P Ley sequence. Winter crops were sown in the autumn preceding the year in which they were harvested.

¹I Jan – Apr, II May – Aug, III Sep – Dec.

²Under-sown in barley (B).