Location: Application Technology ResearchTitle: Lime rate affects substrate pH and container-grown birch trees Author
Submitted to: Communications in Soil Science and Plant Analysis
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/15/2018
Publication Date: N/A
Interpretive Summary: Birch trees (Betula spp.) are reported to suffer from nutrient disorders due to high pH soils in urban landscapes. Little is known about how pH of soilless substrates used in nursery containers affect growth and development of birch trees during production. While substrate pH can easily be modified with incorporation of dolomitic lime, pH in containers can change over time due to acidic fertilizers or alkaline irrigation water. The objective of this research was to determine the influence of substrate pH on growth and development of birch trees in nursery containers. Substrate pH ranged from 4.8 to 7.3 throughout the experiment. Despite differences in substrate pH, there were only few and minor differences in plant appearance and no differences in plant growth. While there were measurable differences in nutrient concentrations in substrate leachates and foliar tissue, these differences were not substantial enough to affect the appearance or growth of birch trees. Based on this data, birch trees grown in a pine bark substrate can be grown over a wide range of substrate pH with little or no effect on their growth or nutrient status.
Technical Abstract: Nursery production of birch (Betula nigra L.) trees commonly occurs in containers using a soilless substrate such as pine bark or peatmoss. Birch trees have been reported to suffer pH-induced micronutrient deficiencies in landscapes, thus they are recommended to be planted in low-pH soils (< 6.5). Little research has addressed the influence of substrate pH on birch trees during container production. Therefore, the objective of this research was to determine if substrate pH influences birch tree growth and development. Birch (Betula nigra ‘NBMTF’) liners were transplanted into 11.4 L plastic nursery containers filled with an 80 pine bark : 20 sphagnum peatmoss (v:v) amended with either 0.6 kg.m-3 of elemental sulfur (S) or 0, 1.8, 3.5, or 7.1 kg.m-3 dolomitic lime (DL). Substrate pH ranged from 4.8 to 7.3 throughout the experiment. There were only few and minor differences in leaf chlorophyll content and no differences in plant growth. Differences in leachate and plant tissue nutrient concentration occurred for some elements, although these differences were not enough to affect plant growth. Container-grown birch trees can be grown over a wide range of substrate pH (4.8 to 7.3) with little or no effect on their growth.