Contrasted growth response of hybrid larch (Larix × marschlinsii), jack pine (Pinus banksiana) and white spruce (Picea glauca) to wood ash application in northwestern Quebec, Canada

Abstract

Biogeosciences and Forestry Biogeosciences and ForestryContrasted growth response of hybrid larch (Larix × marschlinsii), jack pine (Pinus banksiana) and white spruce (Picea glauca) to wood ash application in northwestern Quebec, Canada Nicolas Bélanger (1) , Gustavo Palma Ponce (2) , Suzanne Brais (2) The use of wood ash as a soil amendment in afforestation and reforestation efforts is increasing. While most studies suggest benefits or neutral results on tree growth and survival, a few studies indicate adverse effects. Hybrid larch, jack pine and white spruce were studied at three northwestern Quebec plantation sites after they received wood ash at two application rates. Soil chemical properties, foliar nutrients and seedling growth and mortality were monitored over a period of eight years. The response of soil to ash application was mostly observed in the forest floor and was more pronounced in year 3 than year 8, likely due to the acidifying nature of the boreal soils studied. Jack pine growth increased linearly with wood ash application rates, white spruce growth showed an inconsistent and delayed positive response under the higher application rate, and hybrid larch growth and survival were either increased or decreased under the lower application rate depending of site but decreased at all sites under the higher application rate. The divergence in growth response between tree species underlines a trade-off between species with rapid acquisition of resources (e.g., pine, larch) to species that use more conservative strategies and store nutrients in their tissues for longer periods (e.g., spruce). In the case of hybrid larch, it accumulated larger amounts of Mn in its needles under the higher application rate and thus, the high bioavailability of Mn appears to have been detrimental to its survival and growth. Its higher sensitivity to Mn addition from ash is likely due to its highly acquisitive (nutrients) nature compared to other coniferous species as well as the initial levels of available Mn levels in the soil. The contrasted growth responses reported here under similar growing conditions highlight the importance of identifying suitable species, sites and application rates to maximize the benefits of wood ash amendments for future tree plantations in the boreal forest.

Forest soil biotic communities show few responses to wood ash applications at multiple sites across Canada

“…This indicates that these changes are likely temporary adaptations rather than persistent selective forces that would result in differences corresponding particular functional adaptations or species. The restriction of response to specific soil horizons at different sites, and lack of consistency of response is supported by similar results or lack of significant soil change, either chemical or biological, in other studies 6 , 13 , 19 , 22 , 49 .…”

“…Current guidelines and sufficient economic incentives may justify the use of ash as an amendment. There is interest in applying ash in commercial harvesting operations, but also in small-scale private land-management 13 . It may be worth investigating the time-frame and harvesting practices in which ash should be applied, as there may be different functional effects when ash is applied to older or less intensive harvesting systems compared to clearcut systems where regeneration is at an early stage.…”

“…These alterations have the potential to influence other soil taxa. Ash can contain toxic metals such as cadmium or manganese, and the application process can create physical disruption to soil surfaces and vegetation that may negatively affect soil communities and processes 12 , 13 . On the other hand, ash has been demonstrated to mitigate effects of pollutants, such as Cadmium and antibiotics, on fungal and bacterial community structure and growth 14 , 15 .…”

Wood ash amendments as a potential solution to widespread calcium decline in eastern Canadian forests

“…Jack pine (Pinus banksiana Lamb.) growth increased as ash application rates increased, whereas mixed results were seen in hybrid larch (Larix × marschlinsii), and growth response was delayed in white spruce (Picea glauca (Moench) Voss) during field trials in northwestern Quebec (Bélanger et al 2021). Thus, while species like jack pine may be well suited to treatment with wood ash, others like black spruce (Picea mariana Miller) may not be, as the latter exhibited a negative growth response to wood ash as application rates increased (Emilson et al 2019).…”

Prospects of cultivation of Jack pine (Pinus banksiana Lamb.) on sandy soils of natural–technogenic origin in Kyiv Polissia

“…Under such growing conditions, the survival and biometric indicators of Jack pine are negatively affected by the lack of nitrogen and organic matter in the rhizosphere (Farnden et al 2013). Improvement of survival (by 12-22%) and growth intensity is achieved by feeding pine seedlings with different doses of wood ash (Bélanger et al 2021).…”