Bromegrass Seed Midge Control
The bromegrass seed midge (Contarinia bromicola, Figure 1) is a common pest of smooth bromegrass (Bromus inermis) in Saskatchewan, reported to cause seed yield reductions up to 50% (Knowles 1973). Seed midge damage has not been reported in meadow bromegrass (Bromus riparius) in Saskatchewan but some seed growers have reported damage in hybrid bromegrass (Bromus riparius x Bromus inermis), which was developed from hybridizing smooth and meadow bromegrass.
Two generations of seed midge occur with the adult midge emerging when bromegrass panicles are emerging and again during flowering. Bromegrass seed midge larvae feed on developing flowers and seed and increase seed shattering which reduces seed yield (Neiman and Manglitz 1972). Midge larvae of the second generation that feed on developing seed go into diapause and some fall to the ground within shattered florets, re-emerging the following year as adults.