The Birdsfoot Trefoil on our green roofs is finally in flower. I first noticed it on the shed, but it's now flowering next to the Kidney Vetch on our main green roof. I can also see tiny Birdsfoot Trefoil plants in our developing meadow areas, where they've struggled on through cold and drought. Birdsfoot Trefoil is one of my all time favourite plants. The common name we chose to use knows all sorts of different variations of apostrophe and hyphen; the Latin is Lotus corniculatus. Its flowers are supposed to look like a bird's foot. Hmm! There's also a Greater Birdsfoot Trefoil, more a marsh plant than meadow, and a narrow leaved Birdsfoot Trefoil. As a non-botanist I have to say, gentle reader, I would struggle to spot the difference. Anyway, I know the Birdsfoot Trefoil on the roof is Common. It's a legume (which makes it a favourite with bumblebees in particular); think of it as a retiring native yellow sweet pea. It's also a larval foodplant for surprising number of butterflies too. Although it's typically found in wildflower meadows, Birdsfoot Trefoil's sweet nature (a low and compact habit) and relatively long flowering period makes it perfect for gardens, and we always try to include it in wildflower seed packets for gardeners. As a green roof plant Birdsfoot Trefoil seems ideal, tolerating dry conditions and the wind. I don't just like Birdsfoot Trefoil because it's useful and attractive, but that it's useful and attractive under our noses, largely unnoticed. It's one of those humble common plants we don't properly look at and appreciate.