Red trees

The impact of climate change and summer heat on tree nurseries was discussed recently at the Teagasc Nursery Stock Seminar and in some trade publications. 

By late summer in Ireland, it was clear that tree nurseries had not seen expected increases in tree girth and in particular crown development. Not all stock was as badly hit and soil with higher clay and organic matter content would have done better.

Bavarian horticulture and viticulture institute LWG has been looking at trees and climate change for 15 years. Their research project Stadtgrun 2021 has been growing an extensive range trees, 400 + species and varieties, in two sites in the country representing two dry and challenging climates. Klaus Korber of VLB reviews the findings from their research sites in Taspo the German horticulture magazine “Betula pendula, the native birch is increasingly reaching its limits and was almost completely empty of leaves at some locations in August”. Information of trees that performed badly in heat in Germany original (German) English translation.

Taspo also carried a report of the increased cost of trees because of the heat and drought of summer 2018. The high summer heat had a significant and varied impact on growth. Increased costs of irrigation have had to be passed on to the customer.

UK Barcharm trees sales director Keith Sacre has been concerned to see the lack of diversity in many cities urban forests. His recent presentation at the nursery stock seminar highlight areas such as climate change, pest and disease and quality of roots on longevity.
Teagasc began a small trial in Kildalton College three years ago. So far about 50 less common tree species and varieties have been planted to assess suitability to climate and soil type. The trial will be extended to Ashtown also and will be one to watch over the coming years.