Featured Research

from universities, journals, and other organizations

Extreme Autumn Temperatures Cause Unseasonable Flowering In The Netherlands

Date:
December 22, 2006
Source:
Wageningen University
Summary:
Observers in the Netherlands reported that more than 240 wild plant species were flowering in December, along with more than 200 cultivated species. According to biologist Arnold van Vliet of Wageningen University, this unseasonable flowering is being caused by extremely high autumn temperatures. The mean autumn temperature in 2006 was 13.6C, which is 3.4C above the long-term average. It was even 1.6C warmer than in 2005, which was previously the warmest autumn since 1706, when records were first kept. It is very likely that other European countries also experienced unseasonable flowering due to the high temperatures.

An analysis of the observations revealed that over 240 wild plant species were observed to be flowering during the first 15 days of December.
Credit: Image courtesy of Wageningen University

Observers in the Netherlands reported that more than 240 wild plant species were flowering in December, along with more than 200 cultivated species. According to biologist Arnold van Vliet of Wageningen University, this unseasonable flowering is being caused by extremely high autumn temperatures.

The mean autumn temperature in 2006 was 13.6C, which is 3.4C above the long-term average. It was even 1.6C warmer than in 2005, which was previously the warmest autumn since 1706, when records were first kept. It is very likely that other European countries also experienced unseasonable flowering due to the high temperatures. This information emerged from a unique, large-scale observation campaign conducted by volunteers during the first 15 days of the month.

The flowering observation campaign was coordinated by the Dutch phenological network Natuurkalender (Nature's Calendar), which comprises organisations such as Wageningen University, the FLORON Foundation and the popular nature and wildlife radio programme Vroege Vogels (Early Birds). After the radio programme requested its listeners to make observations of plants in flower on the 10th of December, nearly 2000 observations were submitted by 280 volunteers via the Nature's Calendar website.

The aim of the observation campaign was to determine the effects of the extreme weather conditions in the Netherlands during the second half of 2006. This year included not only the warmest July and September on record, but also the wettest August. Temperatures were far above normal: 3.7C higher in September, 3.3C higher in October and 3C higher in November. The first 17 days of December were even more extreme, registering 4.2C above normal. For the entire autumn the average temperature was 3.4C above the long-term average and even 1.6C warmer than the autumn of 2005, which was previously the warmest on record in the Netherlands.

An analysis of the observations revealed that over 240 wild plant species were observed to be flowering during the first 15 days of December. Examples of such species include Cow parsley, Sweet violet and Evening star. According to scientists at Wageningen University, only 2% of these plants normally flower in the winter, while 27% end their main flowering period in autumn and 56% before October. In addition, the observers reported that more than 200 garden plants were flowering in December.

According to this data, the unusually high temperatures are clearly lengthening the growing season. Leaf colouring and leaf fall of species like Oak and Beech occurred two to three weeks later than the average during the first half of the 20th century. For species such as Hazel, the flowering season began at least one month earlier than normal. Some Rhododendron varieties and Japanese Cherry also flowered at the beginning of December, while they previously flowered at the end of January or February. A complete overview of all the wild plants observed can be found at: www.natuurkalender.nl.

Van Vliet warns that the ecological consequences of the extreme temperatures and the longer growing season remain largely unknown. Next year will be an important year for ecologists to identify the impacts on plants and animals. The high temperatures in 2006 are likely to increase the numbers of warmth-loving species even further, a trend which has been observed for some time.


Story Source:

The above story is based on materials provided by Wageningen University. Note: Materials may be edited for content and length.


Cite This Page:

Wageningen University. "Extreme Autumn Temperatures Cause Unseasonable Flowering In The Netherlands." ScienceDaily. ScienceDaily, 22 December 2006. <www.sciencedaily.com/releases/2006/12/061221232129.htm>.
Wageningen University. (2006, December 22). Extreme Autumn Temperatures Cause Unseasonable Flowering In The Netherlands. ScienceDaily. Retrieved July 23, 2014 from www.sciencedaily.com/releases/2006/12/061221232129.htm
Wageningen University. "Extreme Autumn Temperatures Cause Unseasonable Flowering In The Netherlands." ScienceDaily. www.sciencedaily.com/releases/2006/12/061221232129.htm (accessed July 23, 2014).

Share This




More Plants & Animals News

Wednesday, July 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Michigan Plant's Goal: Flower and Die

Michigan Plant's Goal: Flower and Die

AP (July 22, 2014) An 80-year-old agave plant, which is blooming for the first and only time at a University of Michigan conservatory, will die when it's done (July 22) Video provided by AP
Powered by NewsLook.com
San Diego Zoo Welcomes New, Rare Rhino Calf

San Diego Zoo Welcomes New, Rare Rhino Calf

Reuters - US Online Video (July 21, 2014) An endangered black rhino baby is the newest resident at the San Diego Zoo. Sasha Salama reports. Video provided by Reuters
Powered by NewsLook.com
Shark Sightings a Big Catch for Cape Tourism

Shark Sightings a Big Catch for Cape Tourism

AP (July 21, 2014) A rise in shark sightings along the shores of Chatham, Massachusetts is driving a surge of eager vacationers to the beach town looking to catch a glimpse of a great white. (July 21) Video provided by AP
Powered by NewsLook.com
$23.6 Billion Awarded To Widow In Smoking Lawsuit

$23.6 Billion Awarded To Widow In Smoking Lawsuit

Newsy (July 20, 2014) Cynthia Robinson claims R.J. Reynolds Tobacco Company hid the health and addiction risks of its products, leading to the death of her husband in 1996. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins