Tapping of Maple Resource in VT: NASS estimates ~57,000 ha tapped in VT and according to FIA, VT has ~1.28 million ha of productive, accessible maple-beech-birch forest type, which is primarily composed of maple dominated cover types, indicating that less than 5% of the potential maple resource in VT is tapped. Below is a map of those maple dominated cover types in the state and the sugarbushes from our study.
Map of FIA maple resource and study parcels: FIA data in this map comes from: Riley, K.L., I.C. Grenfell, M.A. Finney, and J.D. Shaw. 2021. TreeMap 2016: A tree-level model of the forests of the coterminous United States circa 2016. Forest Service Research Data Archive, Fort Collins, CO.
Basal area: Small production sugarbushes have the highest basal area, however those for Medium and Large production are also high relative to silvicultural standards. The stocking guidelines represented below are based on a mean stand diameter of 11” (28cm), which is the average for the dataset.
Proportion of property in sugarbush: Large production parcels tapped a higher proportion of their total properties than small
Taps per sugarbush hectare/acre: The density of taps did not vary significantly across production classes, with an overall average of 54 taps per sugarbush acre.
Species composition: Small production sugarbushes had a higher proportion of sugar maple in their overstories
Management Activities: Forest management plans lay out the scheduled activities for the 10 years following writing of the plan. Dividing scheduled management activities for sugarbushes into four categories: stand tending activities (e.g., crop tree release, firewood thinning), regeneration activities (e.g., single tree and group selection, irregular shelterwood), no activity, and non-native invasive species (NNIS) treatment, Large production sugarbushes had significantly more no activity scheduled than Small or Medium, though all had relatively high amounts of no activity scheduled for the next 10 years relative to their stocking
Engagement with Certification
Certification by production class: Large production parcels were more likely than Small to be organic certified, though no significant differences between production classes and engagement with bird-friendly certification were observed
Meeting species diversity standards: The UVA program standards, VOF standards, and BFM standards all require sugarbushes to have no more than 75% of their overstory in sugar maple. Sugarbushes that do not meet these requirements may still be enrolled with a plan to enhance species diversity over time. Sugarbushes with organic or BFM & organic certifications were significantly more likely to comply with this standard than those with no additional certification. We also found sugarbushes with BFM & organic certification to have higher amounts of red maple in their overstories while sugarbushes with no additional certifications had higher amounts of sugar maple