Forage Seed Response to Copper Fertilization

In June 2013, 0.22 lb/ac of foliar EDTA chelated copper was applied at the flag leaf to established timothy (3 locations) and hybrid bromegrass (1 location) on replicated miniplots in the Choiceland, Nipawin, and White Fox SK regions. At Site 1 (field with a history of copper fertilizer application) seed yield of timothy did not increase when copper was applied. At two other sites copper fertilization increased seed yield of timothy by 20 and 29 per cent. At Site 4 seed yield of hybrid bromegrass increased by 30 per cent. The three sites where copper increased the yield had no known history of copper application. Statistical analyses of individual sites did not reveal significant differences; however a combined analysis of the three sites with no known history of copper fertilization indicated that the copper response was significant.

These results suggest that low seed yield with forage grasses may reflect copper deficiencies. Forage seed growers who suspect copper deficiencies should consider applying copper to test strips in their fields to verify both the presence and magnitude of responses.

Based on 9.5 per cent EDTA chelated copper priced at $9/L, the cost of 0.22 lb/ac would be about $9.50/ac. With typical yields of 250 lb/ac for hybrid bromegrass and 300 lb/ac for timothy, the resulting yield increases in three of these sites provided positive economic returns.

These results show that application of foliar EDTA chelated copper at relatively low rates can be effective at correcting deficiencies. Applying foliar copper to miniplots and comparing yield to adjacent untreated areas is an effective way of identifying where copper applications may be economic.

SFSDC wishes to acknowledge the efforts and expertise of Stu Brandt, Dr. Sukhdev Malhi and the Northeast Agriculture Research Foundation as well as Clayton Myhre, Pickseed Canada in carrying out this project. To look at the full research project report, please click on Research on the website menu and look under Past Research for “Forage Seed Response to Copper Fertilization”.