Hazel Catkins, the wind pollinated male flower of the Hazel tree. In fact there are 240 flowers on each dangly stem. I can attest to how much pollen they produce because I accidentally bashed a branch recently. I was covered in a cloud of yellow dust.

 Hazels have both male and female flowers (which are tiny) but the tree cannot pollinate itself so the pollen must alight on another Hazel. The female flower looks like a bud with a red tassel, just about visible to the right of the Catkins seen here: