Posted: Wednesday 21st June 2017 by 30DaysWild2017
Five birch trees one just showing bud burst on the summer solstice
We might be sweltering, plants might be wilting, but those late sharp frosts left their mark. Global warming is about weather change, not just temperatures.
It’s the summer solstice and the temperatures are high. We are told the warmest day for 41 years. So our thoughts naturally turn to global warming. Insects are superfast today, their metabolism boosted by the heat; dragonflies and butterflies are zooming about. Never stopping, impossible to photograph. As I tried in vain to follow an Emperor Dragonfly my attention came to rest upon a group of five Birch trees that I had planted two years ago. One of the trees looks dead.
The dead looking one is in fact alive, with proof provided by very recent bud burst. The tree had come into leaf and provided a show of beautiful catkins in early spring. But then zap; we had a couple of late sharp frosts. The leaves and catkins shrivelled and that is how they have stayed. I kept checking that the tree was still alive, but no new growth has been visible until right now. Those couple of late frosts caught a lot of plants out, quite a few fruit trees failed to get pollinated with the result that there will be few apples and pears for me to pick in the autumn.
What has that late frost and the high temperatures of today in common? It is, of course, climate change. While the average temperature of the world increases year-on-year (last year was globally the warmest on record) the patterns of weather are also changing. It is not a surprise. Climate scientists warned us about it long ago. More energy in the climate system means more perturbations, more extremes, less predictability, the breaking down of seasonal patterns.
The Woodland Trust’s Nature’s Calendar recording scheme has been stacking
up evidence that seasonal patterns are breaking down in terms of when spring’s wildlife events occur. Yes, nature’s events are coming earlier, but we are now starting to see real disruption in the patterns, as evidenced by those late frosts. These changes clearly have long term effects. I wonder whether my birch tree will in fact put on any growth this year. I wonder how this event in its life will show up in its tree ring pattern. Will here just be a line for 2017, not a ring showing growth?
Can we do anything about it? For a start heed all the advice about reducing your consumption of energy based upon fossil fuels. An equally important way is to help conservation organisations put into practice that mantra, “Bigger, better, more joined up”.
“Bigger” areas for nature are more resilient to perturbations. Within a group of trees of the same species there will be diversity in when they grow and how they grow. So, with luck, whatever the scenario of change in weather patterns, natural selection will have something to work on and ensure that some plants survive if others do perish. I had five birch trees and only one was hit by that late frost, the others showed later bud burst and missed being frosted. But what if this had been my only birch tree?
“Better” means making sure that there is a full network of interacting plants and animals. This means that biodiversity is maximised so that species can find different resources should any particular one fail.
“More joined up” means ensuring that wildlife and ecological processes can function across and between a range of habitats. These are routes of land, dedicated to wildlife, that run through the landscape. We need to join rivers to woodlands, marshes to rivers, meadows to hedges, predators to prey, and so on. In effect the more main habitat types that are joined together in a string of “reserves” the more likely a landscape will be able to accommodate climate change and changes in weather patterns.
Graham Martin, Chair of the Worcestershire Wildlife Trust, opinions are my own not those of the Trust. graham@worcestershirewildlifetrust.org, @GrahamMartin99