As a conservation biologist, forester, and maple syrup producer, the Bird-Friendly Maple Project represents a perfect alignment of passions and professions. This initiative beautifully bridges the worlds of bird conservation and the maple community, and for my family’s maple operation, joining was a natural and rewarding decision. This article will explore what the project signifies to me and how it has influenced the management of my own sugarbush.
For many, Vermont is synonymous with maple syrup, producing nearly half of the U.S. output. However, fewer realize that the same forests that sustain the maple industry also serve as crucial nesting grounds for a remarkable diversity of bird species. Recognizing this synergy, the Bird-Friendly Maple Project was established in 2015 through a collaborative effort between Audubon, the Vermont Maple Sugar Maker’s Association, and the Vermont Department of Forests, Parks, and Recreation. The project aims to integrate and promote these two vital aspects of Vermont’s forests. It’s important to state upfront that, in my opinion, all sugarbushes inherently benefit birds. Tapping maple trees helps preserve forests, which is paramount given that habitat loss is a significant threat to bird populations. However, the specific management practices within a sugarbush can elevate it from merely being “okay” to becoming high-quality nesting habitat where birds can successfully raise their young. For me and the over 50 other producers statewide who have committed to bird-conscious sugarbush management, this participation also brings a distinct marketing advantage. Unique labeling, signage, and promotional materials allow us to inform our customers about our intentional efforts to conserve birds and their habitats while producing exceptional maple syrup.
Understanding Avian Habitat Needs in Sugarbushes
As a child, my drawings of trees invariably featured a bird’s nest perched at the very top. In reality, birds utilize various forest strata for nesting and foraging. Different species can be found nesting and seeking insects at all levels of the forest, from the ground to the upper canopy, with the majority occupying the middle layers. To support a diverse array of bird species, it’s essential to maintain a variety of tree sizes within your sugarbush.
The understory, the first six feet of the ground, is often characterized by dense patches of seedlings, saplings, and shrubs. This layer provides critical habitat for birds such as the Black-throated Blue Warbler. In my sugarbush, American beech dominates the understory, interspersed with scattered striped maple and red spruce. From a broader forest health perspective, incorporating other plant species would be beneficial, and this is a key objective of my forest management plan.
The midstory, spanning a height range of 6 to 30 feet, is formed by larger saplings, smaller pole-sized trees, and the lower branches of larger trees. This habitat feature is well-established in much of my sugarbush, making it an ideal nesting location for species like the Wood Thrush and Red-eyed Vireo, whose songs I frequently hear. However, the continued prevalence of American beech in this layer raises concerns about the future diversity of tree species.
When establishing and managing a maple sugarbush, the abundance of sugar and red maple is a logical consideration, as a forest with only 10-20% maple is unlikely to be considered a prime sugarbush. My sugarbush currently comprises about 37% sugar and red maple, with the remainder being a mix of associated hardwoods such as American beech, white ash, yellow birch, aspen, red oak, and basswood, along with some eastern hemlock. While this composition might not be the first choice for all sugarbush operators, for me, it’s nearly ideal (aside from the beech dominance!). This diverse tree species composition supports a richer bird community and a healthier overall forest. I believe the long-term health and integrity of the forest outweigh any potential sacrifice in near-term sap production. My management plan focuses on fostering tree species diversity, including promoting the growth of red spruce in the understory and eastern hemlock in the midstory and upper canopy. The presence of softwoods is particularly important, attracting species like the Blue-headed Vireo and Blackburnian Warbler, which associate strongly with conifers. Yellow birch and red oak further enhance insect diversity, a vital food source for nesting birds.
Last week, while surveying my woods, I encountered several fallen trees that had disrupted the lateral lines of my tubing system. While initially frustrating due to the added work, this event also highlighted the value of coarse woody material on the ground, an important habitat element for Ruffed Grouse. Before these trees fell, standing dead trees, or snags, provided essential nesting and foraging opportunities for cavity-nesting birds like Pileated Woodpeckers. Although snags and falling branches can sometimes obstruct my tubing system, it’s a valuable reminder that I am operating within a dynamic forest ecosystem, and my management should work in harmony with its natural processes.
Silvicultural Practices for Avian Well-being
Achieving optimal bird habitat and sap yields requires deliberate and active forest management, including appropriate silvicultural treatments. I am currently updating my 10-year forest management plan with a focus on integrating bird habitat goals with sap production. Based on forest inventory data, I will be implementing treatments derived from “Silviculture with Birds in Mind,” a guide developed through another Audubon and Vermont Department of Forests, Parks, and Recreation partnership.
A common silvicultural practice in sugarbushes is crop-tree release (CTR), which involves identifying desirable “crop” trees (typically maples) and harvesting surrounding trees that impede their growth. This enhances the crop trees’ development, leading to increased sap production. I will be employing a variation of CTR that includes canopy gap formation. My crop trees will include maples as well as other species with high habitat value, such as red oak and yellow birch. Additionally, I will create circular canopy gaps, ranging from 30 to 75 feet in diameter, between crop trees. Within these gaps, all poor-quality stems greater than one inch in diameter at breast height (DBH) will be removed. The purpose of these gaps is to stimulate understory growth, thereby enhancing habitat structure. This approach may also involve removing diseased or damaged maples, which is a beneficial outcome for overall forest health. This integrated silvicultural treatment offers a triple win: increased sap production, improved habitat structure, and enhanced forest health.
Broader Benefits Beyond Bird Conservation
As a conservation organization, Audubon Vermont is dedicated to protecting birds and their essential habitats. The Bird-Friendly Maple Project directly contributes to this mission while also supporting a vibrant forest economy. Healthy forests, managed with birds in mind, offer numerous co-benefits, including increased resilience to climate change, enhanced carbon storage, a buffer against invasive insects, and improved water quality. The Bird-Friendly Maple initiative not only promotes Vermont’s esteemed maple industry but also highlights the excellent forest stewardship practices associated with it. It engages consumers in conservation efforts by encouraging support for maple producers who intentionally integrate bird and habitat considerations into their sugarbush management. In today’s world, conservation is a collective endeavor.
I extend an invitation to both maple producers and enthusiasts to join the Bird-Friendly Maple Project. It offers a truly “sweet deal” for everyone involved.
For further information, please visit https://vt.audubon.org/maple or contact Audubon Vermont at 802-434-3068.
