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Trees And Change Of Temperature.

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From English Mechanic 17th December 1897

It looks as if we were gradually but surely passing to a lower general temperature in these latitudes. Observations does not, it is true, show that the mean temperature is lower than it was century ago; but the disappearance of many plants which formerly flourished on this island and in central Europe seems to indicate that such a change is in progress. A writer in La Semaine Horticole draws attention to certain changes which have occurred and are occurring in France at the present time, which favour the idea that the climate is becoming cooler. Many trees that formerly flourished in the north of France are no longer found there, and can only be met with in the extreme south, while several have disappeared entirely from the country. The lemon once so general and prevalent in Languedoc, no longer grows there and an orange tree cannot be found in Roussillon, where orange groves existed long ago. The Italian poplar so common and so pictersque in ancient French etchings, is now rarely found on French soil, and only in southern part of the Republic. France was of old fruit garden of Europe; but the change of temperature have greatly limited the number and variety of fruits which can be grown in that country and considerably restricted the area in which they flourished.

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From English Mechanic 17th December 1897

It looks as if we were gradually but surely passing to a lower general temperature in these latitudes. Observations does not, it is true, show that the mean temperature is lower than it was century ago; but the disappearance of many plants which formerly flourished on this island and in central Europe seems to indicate that such a change is in progress. A writer in La Semaine Horticole draws attention to certain changes which have occurred and are occurring in France at the present time, which favour the idea that the climate is becoming cooler. Many trees that formerly flourished in the north of France are no longer found there, and can only be met with in the extreme south, while several have disappeared entirely from the country. The lemon once so general and prevalent in Languedoc, no longer grows there and an orange tree cannot be found in Roussillon, where orange groves existed long ago. The Italian poplar so common and so pictersque in ancient French etchings, is now rarely found on French soil, and only in southern part of the Republic. France was of old fruit garden of Europe; but the change of temperature have greatly limited the number and variety of fruits which can be grown in that country and considerably restricted the area in which they flourished.

Interesting discussion, could this not simply be related to urbanisation and lack of re-plantation?

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Check the date: 1897, not 1997!

Yes there was urbanisation in 1897

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Plant hardiness zones do move but it's difficult for me to take that account of 1897 as being indicative of climate change based as it is, on only two species. Regardless of modern climate change, there is little overall difference between here and much of France, obviously there are smaller scale changes due to micro climate but as a general rule, they are very similar. Here is an up-to-date map of hardiness zones:

http://www.uk.gardenweb.com/forums/zones/hze.html

Oranges and Lemons have never been planted in large numbers as a productive crop in France, they have been tried (hence there may have been groves) but they haven't been successful. They are very sensitive to frost and sub-zero temperatures, it's not just the crop which is lost but the whole tree too if the frost is sharp enough. Historically in Europe they were grown in Spain, Portugal and Italy; efforts to introduce them to northern parts sparked the design and growth of purpose built buildings (Orangeries) which in turn led to the introduction of greenhouses.

http://lib.ucr.edu/agnic/webber/Vol1/Chapter1.htm

Styles and fashions in gardening throughout the ages has led to species being popular and widespread for periods of time, only for them to fall out of favour and almost disappear from the landscape. I suspect the decline of Italian Poplar owes much to this reason for it's decline in France, than anything else. In the mid to late 18th century a more natural landscape style was in favour, this spread throughout Europe and led to broader canopied trees being planted rather than columnar shapes more associated with formal, Italianate designs. The Poplar has a short lifespan, this would have led to a natural decline in the numbers being seen.

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Not in France, which has a larger surface area than the UK and much lower population density. Especially not in Languedoc and Roussillon, the places mentioned which are in the South of France (France is most urbanised in the North around Paris).

Urbanisation won't be a factor.

The Little Ice Age caused land use changes. Colder weather made it more difficult to grow Mediterranean fruit trees even in the South of France (presumably because of late frosts).

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The Little Ice Age caused land use changes. Colder weather made it more difficult to grow Mediterranean fruit trees even in the South of France (presumably because of late frosts).

When it comes to citrus fruits, it makes no difference what time of year a frost occurs, they're just not hardy. Most won't tolerate temperatures lower than 5c, with some the lowest is 13c.

http://www.rhs.org.uk/GROWYOUROWN/citrus.asp

Recent years have seen entire groves wiped out in the USA due to freezing, despite efforts including tenting with heaters beneath to prevent damage, and that's despite years of breeding to increase frost tolerance of species.

The little ice age is a known phenomena, I'm not disputing that but taking citrus trees and Lombardy Poplars as being a measure of that is not reliable or indicative. I spend my working life restoring and maintaining historic parklands, gardens and landscapes; fashions of the time dictated what was planted far, far more than climate.

Farming crops such as wheat yields in Europe and time of flowering of Cherry trees in China give much more valid information for this period.

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Land use changes have affected local climates. Forested valley slopes cleared for vineyard cultivation create frost hollows where once protected sun traps harboured orange groves. Which do you prefer, wine or marmalade?

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A report from 1897 may not be reliable but a retreat south is what you'd expect to happen to the Mediterranean tree line after a lengthy dip in temperature.

Since the article refers to "a century ago" we know that the intervening period had the Dalton Minimum. This had ended by the time the article was written (1790-1830), hence the writer could say the mean temperature (now) was not lower.

When the article says France was the "fruit garden of Europe" the phrase "of old" probably refers to the MWP rather than the 18th Century.

The Languedoc wine region in France has a history dating back to 400 BC. Unless it can be shown vast swathes of forest were felled in the 19th Century I suspect frost hollows don't provide the explanation.

Also, you might think if there was a very obvious cause, like urbanisation or Frenchmen chopping down the orange groves for firewood, that the article would have mentioned it.

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Land use changes have affected local climates. Forested valley slopes cleared for vineyard cultivation create frost hollows where once protected sun traps harboured orange groves. Which do you prefer, wine or marmalade?

I Spent some time last weekend in Dorking Surrey walking through a vineyard where the plants were laden with grapes and no rush by the staff to harvest them. Twenty years ago that was in the I'll Never see that category.

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But are you prepared to buy shares in English Wines Group?

Not without checking everything out not just weather possabilities

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