First I've seen in flower and it's 5 petalled again.
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According to Francis Rose's The Wild Flower Key, the bedstraw family can have either 4 or 5 lobes on the corolla and doesn't give a specific 4 or 5 lobes for either cleavers or heath bedstraw. I have to admit, I've never really looked closely at the flowers of bedstraws before - I have always seen the whorls of leaves, then looked at prickles on leaves and considered habitat. Looking at the leaves under a x 10 handlens shows why this plant is so successful at clinging on to anything that passes it!
I've probably not paid great attention to it before but when I have looked at the flowers I've always "seen" four petals. This year I'm suddenly seeing 5 petals on these (and the tormentil I posted recently). Maybe the shape of 5 catches my attention more than the shape of 4 at the moment.
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