Can there be a better walk to the swimming baths? Trunks rolled in towel, I set off down Green Lane, an old cart track running from our village to its market town of Thirsk. The wide verges were blooming with spring. Stitchwort wove white lace in the grass; forget-me-nots seemed to draw down the cloudless sky; the first crimson clover was opening. But it was the crosswort that kept bringing me to a halt. With its small, cross-shaped leaves, and tiny, soft-yellow flowers, individual crosswort plants would be easy to miss; fortunately they grow in colonies.