This investigation was carried out at two locations of sulaimani region were Qlyasan and Kanipanka during the winter season of 2017-2018 to study the response of some narbon vetch lines to different harvesting stages for forage yield and its components under rainfed condition, experimental design was split plot with RCBD arrangement in three replications, six lines of narbon vetch were allotted in main plots, and subplots consists of different harvesting stages were (beginning of flowering, 50% flowering and full flowering). Mean comparisons was carried out according to least significant differences (LSD) test at 0.05 significant levels. The results indicated that the effect of varieties on forage yield and its components was significant for dry forage yield, dry matter%, fresh leaf%, fresh stem% and dry leaf%, Maximum values were exhibited by line 2 and line 5 respectively in Qlyasan location. But, in Kanipanka location, line 5 and line 1 gave maximum values respectively, while in the average of both locations, the highest value of dry matter% obtained by line 1. Line 5 recorded the biggest value of fresh and dry leaf%, while line 2 gave maximum fresh stem% in Qlyasan location. But in Kanipanka location, line 3, 2 and 1 had the maximum values of these traits frequently. Considering the average of both locations, line 3, 2 and 5 had the highest percent of fresh leaf, fresh stem and dry leaf respectively. The effect of harvesting stages on all forage yield and its components was significant, harvesting at full flowering stage gave maximum values of fresh, dry forage yield and dry matter% for Qlyasan, Kanipanka and their averages. Regarding fresh leaf%, fresh leaves per stem ratio, dry leaf% and dry leaves per stem ratio, the harvesting stage at the beginning of
flowering exhibited the highest values for Qlyasan, Kanipanka and their averages. But maximum value of fresh stem and dry stem% were obtained by harvesting at full flowering stage in Qlyasan, Kanipanka and the averages of both locations. Regarding the effect of locations on all forage yield and its components, Qlyasan location predominated Kanipanka location for most traits except fresh and dry forage yield traits which was found significant in kanipanka location in compare to Qlyasan location.