On a warm afternoon in late July, walk the edge of almost any rough field, verge or railway bank and you will find a plant that the law of the land would call a weed. Common ragwort stands waist high, its flat-topped blaze of yellow flowers loud against the drying grass. Look closer and the flowers are busy: hoverflies, solitary bees, soldier beetles, the odd gatekeeper butterfly. And on the leaves, if you are lucky, a row of caterpillars in black and gold hoops, feeding shou

"Save the bees" may be one of most successful conservation slogan of our age. It is on tote bags and T-shirts, in supermarket campaigns and children's books, and it has done a great deal of good in waking people up to the plight of pollinators. But it carries a rather awkward problem. The bee that most people picture when they hear it, the honeybee in its wooden hive, is largely doing fine. In some places it is doing a little too well. And the bees that genuinely need saving

Dragonflies were mastering flight three hundred million years before the first bird. They hunt with incredible precision, live most of their lives unseen underwater, and one of them holds the record for the longest migration of any insect on earth. They are also a living verdict on the health of your water, and one of the very few wild wonders you can summon to your own patch by digging a simple pond with shallow margins and a few plants. A dragonfly hangs in the air at the e