This bright and cheery yellow flower is solidago, commonly known as goldenrod, from the family Asteraceae.
The state flower of Kentucky, it is a native of North America, but became a popular garden flower in Europe. It was used in herbal remedies for kidney problems. Thomas Edison managed to produce rubber from the plants. Henry Ford gave him a Model T with tyres made from goldenrod rubber. However, the yield and quality were not good enough for commercial use.
Although the flowers sway wildly on a windy day (hence the blurry photos) they are insect pollinated not wind pollinated. As well as attracting a wide variety of bees they are also a food source for lepidoptera larvae.