You need to stop reading this and go outside right now. Find the nearest hazel or filbert hedge, and break off one of the clusters of nuts.
|Hazelnut in the husk|
If you don't break of this cluster, the squirrels will in a matter of days, so don't feel too guilty. Of course, don't do anything that will get you in trouble, either!
The cluster of hazelnuts in their cases will be jade green and frilly, a group of lacey collars enclosing green or tan seeds. Put a thumb on the tannest nut, and try to move it. If it roles free from the husk, it's ripe enough to eat, though perhaps not for long-term storage. If not, it doesn't matter for what you are going to do. Peel back the husk instead.
|Insert nose here|
I have no idea why hazelnut husks smell so wonderful. Maybe to help attract squirrels? Though they consume many nuts, squirrels greatly benefit the few that survive. By dragging them off and burying them, squirrels serve as the distribution system for the seeds, allowing them to grow far from the tree. That is idle speculation, though. Seriously I have no clue. But seriously, they smell great.
|A good nut|