To investigate the effects of intercropping ratios and cutting periods on forage production performance in a rapeseed-oat mixed cropping system， this trial measured and analyzed forage yield and quality indicators across nine mixing ratios and three cutting periods for the rapeseed （‘Qingyou No. 21’）-oat （‘Lena’） system. Results indicated that dry hay yields at the late rapeseed flowering stage （A₂） and the rapeseed pod milk stage （A₃） were significantly higher than at the peak rapeseed flowering stage （A₁） （P<0.05）. The relative feed value at A₃ was significantly higher than at A₁ and A₂ （P<0.05）. At A₃， the 5∶5 rapeseed-oat mixture （A₃R₅O₅） exhibited the highest land equivalent ratio of 2.21. TOPSIS multi-criteria decision analysis indicated that during A₃， the 7∶3 rapeseed-oat mixture （A₃R₇O₃） achieved the highest fit index of 0.75. This treatment exhibited comparatively high hay yield （454.16 kg‧hm^-2） and land equivalent （2.16）， with lower acid-detergent fiber （69.19%） and neutral-detergent fiber （38.64%） content. This constitutes an agronomic practice suitable for promotion within the study area.

Intercropping ratio  /  Mowing period  /  Mixed cultivation of rape and oat  /  Biomass  /  Forage quality  /  Interspecies competition