Catkin

Definition

Hazel, oak and birch catkins are wind-pollinated and offer no nectar. Willow is the important exception: its catkins are insect-pollinated, and male willow catkins are among the most critical early pollen sources in the northern hemisphere. Female willows produce nectar and no pollen.

Plant records that discuss this

• Sweet chestnutAn exceptional pollen source — the catkins shed enormous quantities — and a good nectar source in the right weather. The pollen arrives at a useful moment for colonies building towards late summer.
• Goat willowThe single most important early-season pollen source across much of Europe. Its value is not in yielding honey but in what it makes possible six weeks later.
• HazelThe clearest illustration in the catalogue of why nectar and pollen are rated separately: hazel scores zero for one and top marks for the other, and it matters enormously.

Bee records that discuss this

• Vernal colletesA large spring plasterer bee that emerges in March for willow catkins and forms some of the most spectacular nesting aggregations in northern Europe — tens of thousands of burrows in a single dune slope, with clouds of males patrolling above them waiting for females to emerge.