Plant of the Week: Grey birch

Grey birches give us so much to discuss! Ornamental gardeners may first point out the unique form and chevron-marked bark (both on display this season). Or perhaps they will focus on the foliage-glossy green leaves that move well in the wind and turn an attractive yellow in fall. The practical gardener will tell you that the tree is a highly adaptable, pioneer species, able to establish in poor soils where others cannot. Still others may mention the edible attributes of the tree, such as the fermented "birch beer" concocted from the birch sap. I recently tried a can of "birch water" after a hiking trip- I couldn't resist!

I'd like to comment on a specific feature of Betula populifolia that perfectly marries the art and science of horticulture. The tree is monoecious, meaning male and female flowers exist on the same specimen. Not only is this an interesting characteristic from a botany standpoint, but it adds another dimension of aesthetic interest, especially in winter. The flowering structures of birch trees are called catkins. At this point in the season, the grey birches exhibit both the immature male catkins, as well as the matured, seed head-like female fruiting structures. Right now, both are highly visible, hanging from the wiry twigs of the tree's bare branches. The immature male catkins are thin and curved, longer than the female parts. The matured female fruiting structures are actually from last year, and appear denser, shorter, and squatter than their male counterpoints are. Together, the two structures provide not only botanical interest, but also enhance the winter silhouette of the trees. I invite you to take a closer look at these contrasting structures next time you are in the park.

PLANTING TIP:
Betula populifolia provides year-round interest in the garden. I recommend planting in groups, rather than a lone specimen. Not only does the species prefer a colony, but a grouping is much more naturalistic and visually impactful. The tree is native to Eastern North America, recorded from Quebec in Canada to its southern limit in Shenandoah National Park. While it will establish in poor, disturbed soil sites, it is most at home in moist woodlands.

WHERE TO FIND THIS PLANT:
You can view our most striking stand of grey birches in the Gansevoort Woodland, between Gansevoort St. and West 13th St.

Our horticultural team counts on members and friends like you to help keep the High Line beautiful and thriving. Join our community of supporters who play an essential role in the High Line's most important gardening projects.


TD Bank is the Presenting Green Sponsor of the High Line.

Recent Posts
Plant of the Week: Gibraltar bushclover
view post
Gardening in the Sky: An Increasingly Rare Breed
view post