Gorse can be found in bloom in every month of the year, even in the depths of winter. I don't know how many of these flowers produce seed without bumblebees and honeybees to pollinate them but I do know, from experiments I did years ago, that their pollen is viable and capable of germinating at low temperatures, close to freezing. So it may be that, with some violent buffeting from winter winds, some pollen is shaken onto stigmas and they do produce some seed.
If they do, then they may avoid seed predation by the gorse weevil Exapion ulicis, which hibernates through winter. This little beetle emerges from hibernation in spring and lays eggs on the ovary, where its grubs feed on the developing seed through the summer. They pupate as the pod ripens and adults often hatch in the pods, only to be thrown out along with any remaining seeds when the pods burst open on warm summer days.
When the autumn weather is wet some of the seed pods do not develop walls that are brittle enough to split open, so the weevils die, trapped inside. I took some old, undehisced pods home and opened a few to see if there were any dead weevils inside, and found a few live ones.
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