Exploding seed pods?!? Flowers in the winter?! Many species have evolved unusual strategies for reproduction, and this month’s target species is no exception. Witch Hazel (Hamemelis virginiana) is a small tree of the eastern forest understory that is easy to miss. It’s small and unassuming, but closer inspection reveals an array of fascinating adaptations that make it unique among our woodland species. Join Steve and Bill as they hunt for this wonder of the woods and share what they learned about it. This episode, they are joined by friend and author Gerry Rising, who recently published Birds and Bird Watching-100 Brief Essays. This month’s episode was recorded at the Reinstein Woods Nature Preserve & Environmental Education Center in Depew, NY.
The Cutting Room Floor:
1. We talked about how <1% of the flowers actually become fruit and why that may have evolved, but you didn't hear that the sheer number of flowers may also be a strategy for attracting pollinators in a season with very few.
2. After Gerry left, Bill and Steve went back to take some pictures and we found some flowers! Witch-hazel flowers have 2 fused carpels (the female parts) terminating in a branching style (think the letter "Y"). This flower also has 4 tall inward leaning stamens (the male parts) alternating with 4 short staminoida (sterile stamens) shiny with nectar. The flower is set up this way because insects will brush up against the stamens and styles to get to the nectar on the staninoida. By doing this, the insect (probably a fungus gnat, Bradysia spp.) deposits foreign pollen on the styles and picks up new pollen from the stamens for future flower visits.
Photo credit: backwaterbotanics.wordpress.com
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