Sugar maple decline and lessons learned about Allegheny Plateau soils and landscapes

Abstract

Insights for Managers • A long-term forest liming study showed the critical importance of base cations for sustaining sugar maple crown health, growth, and survival. • A topographic gradient study examined the distribution of base cations on the landscape in relation to sugar maple health and found that unglaciated summits, shoulders, and upper backslopes had the most crown dieback and mortality. • Foliar calcium and magnesium were lowest on the unglaciated upper landscape stands and, combined with two or more moderate to severe defoliations in the preceding 10 years, cause extensive sugar maple dieback and mortality. • Bedrock parent material and hydrologic flow paths were important factors that affected where sugar maple declined on unglaciated sites. • A 30-year retrospective study that used archived soils from four forested and undisturbed sites originally sampled in 1967 showed that changes in soil base cation status and acidity over 30 years was a predisposing stressor for sugar maple. • This multidisciplinary research produced a new understanding of the factors that led to the widespread sugar maple decline episode.

Strategies of tolerance reflected in two North American maple genomes

“…Throughout A. saccharum ’s native range, when calcium is deficient, additional nutrient imbalances, such as magnesium, phosphorus, potassium, and nitrogen deficiency, as well as high aluminum and manganese concentrations, climatic effects, and biotic stressors, such as defoliation, create compounding stress (Bal et al., 2015 ; Long et al., 2019 ). Samples from unamended plots show an increase in stress response perhaps reflective of calcium deficiency combined with external stressors.…”

50 years ofscience-management cooperation

“…This research received consistent funding from the National Pesticide Impact Program and its successors, a great deal of in-kind support from the ANF, and led to landmark publications , Trager et al 2013. Long et al (2019) describe the scientific advances associated with some of this research. Early tests of the role of site factors such as nutrition and moisture in the mid-20th century regeneration crisis did not show these as highly important causal factors.…”

Strategies of tolerance reflected in two North American maple genomes

“…saccharum requires nutrient-rich soils, and calcium is the common limiting element underlying maple decline. Increased acid deposition in regions of low base cation concentration limits calcium availability (Long et al, 2019;Schaberg et al, 2001Schaberg et al, , 2006Sullivan et al, 2013), but trees improve long-term with the addition of calcium (Moore & Ouimet, 2021). Additional nutrient imbalances, such as magnesium, phosphorus, and potassium and nitrogen deficiency, as well as high aluminum and manganese concentrations, climatic effects, and biotic stressors such as defoliation, are compounding factors, culminating in widespread decline that has been studied throughout most of A. saccharum's native range (Bal et al, 2015).…”

“…Throughout A. saccharum's native range, when calcium is deficient, additional nutrient imbalances, such as magnesium, phosphorus, potassium, and nitrogen deficiency, as well as high aluminum and manganese concentrations, climatic effects, and biotic stressors such as defoliation, create compounding stress (Bal et al, 2015;Long et al, 2019). Samples from unamended plots show an increase in stress response perhaps reflective of calcium deficiency combined with external stressors.…”

“…Studies from locations such as Vermont, the Adirondack Mountains, and the Allegheny Plateau, have linked foliar aluminum and calcium levels (Long et al, 2019;Oswald et al, 2018;Sullivan et al, 2013) and stem aluminum levels to branch dieback as seen in maple decline (Mohamed et al, 1997). At HBEF, previous studies examined physiological effects of aluminum with a multitissue study on mature A. saccharum.…”