Every piece of the natural world is important, playing a role in supporting other pieces and keeping the whole shebang stable and resilient. But some species seem to do more than their share.
A good example would be the Eastern red cedar, Juniperus virginiana. This familiar tree occurs in most of the U.S. east of the Great Plains, with its current range extending into limited portions of Southern Canada. Its native range appears to have been somewhat more restricted; this is a species that has benefited from planting by humans for various purposes. But this is a versatile species, occurring across an unusually wide range of latitudes and growing happily in an exceptional diversity of habitats and soil types, from wetland edge to near-desert.
A locally common tree on Martha’s Vineyard, Eastern red cedar is a potent colonizer of open habitats. Given enough time, it is eventually shaded out by taller oaks. But its seeds, readily dispersed in bird droppings, can take root nearly anywhere, and if your goal is to keep a patch of open habitat open, you could easily come to resent the zeal with which this small tree reproduces.
Eastern red cedar is easily recognized by its fibrous bark, short, tight needles, and in fall and winter, its bluish, berrylike cones, usually frosted with waxy gray scaling. Tastes vary, but I find this tree to be an attractive one, often growing with an erect, flame-shaped habit. Forty feet tall is very large for this modestly sized species, but its rapid growth rate can keep it ahead of competitors for many years.
Red cedar first got onto my radar in the early 1990s, as my interest in butterflies started to intensify. This tree is the usual larval host plant of one of our region’s most beautiful and interesting butterflies, the juniper hairstreak. The association is a close one: It is unusual to find the butterfly more than a few yards from a cedar, and the classic way to find this hairstreak is to grab the tip of a cedar branch and yank. Male hairstreaks, if present, will be perched at the ends of twigs, and will burst into swirling flight when you shake the tree. A chance to see this gorgeous green butterfly is well worth the itch of dislodged cedar needles falling inside your shirt.
I’m not aware of much else that feeds on the needles of red cedar, which are tough and scaly and surely require some specialization of your innards to digest successfully. But the berrylike fruits are a seriously popular food source for wildlife. Robins, flickers, cardinals, orioles, blue jays, and the aptly named cedar waxwings are among the birds I commonly see feeding on red cedar. At this time of year, an astute birder will not leave a fruit-laden cedar unexamined.
Perhaps surprisingly, cedar cones appear to be an important food source for flies, as well. It’s not entirely clear to me whether flies feed on the waxy coatings of the fruits, on the juice of the fruits themselves, or on both. But feed they do, and for the many species of blowflies and hover flies that remain active this late in the season, cedar fruits look to me to be among the most important natural food sources.
The structure of red cedar, both the dense foliage of the overall tree and the finely scaled composition of the needles, also represents a resource for wildlife. Many smaller birds, notably chipping and field sparrows, favor red cedar for nesting, presumably because the opaque foliage and prickly needles offer concealment and protection from avian predators.
And vast numbers of tiny insects find shelter among the needles of this important tree. On the next mild, sunny day, shake a cedar branch and watch how many tiny bugs take flight: winter crane flies, midges, and moths. Augmenting these adults are countless larval or pupating insects, often undetectable to obtuse human vision, but easily found and winkled out by the sharp eyes and needlelike beaks of kinglets, wrens, and chickadees.
And while the season for finding them is now past, I cannot avoid mentioning the association between red cedar and the jumping bush cricket (Hapithus saltator). For reasons known only to the insect itself, Hapithus prefers conifers, and also prefers to hang out on branches just a few feet off the ground. These dual preferences lead inevitably to the lower limbs of bushy red cedars.
It’s not really my department, but the human uses of red cedar merit mention. The dense foliage, fast growth, and bulletproof constitution of this species make it a useful landscaping plant. And the rot-resistant, aromatic characteristics of red cedarwood make it suitable for uses ranging from exterior shingling to the lining of drawers for bedding or clothing storage.
It’s easy to take common, hugely successful species for granted. But it is often these common organisms that keep the natural world ticking. And especially when winter reduces the options available to wildlife, Eastern red cedar stands out as a critical resource.
