scholarly journals Winter Protection of Tree Ferns at the Royal Botanic Garden Edinburgh

2007 ◽  
pp. 141-154
Author(s):  
Andrew Ensoll ◽  
Louise Galloway ◽  
Alastair Wardlaw
Keyword(s):  
Air Temperature ◽  
Royal Botanic Garden ◽  
Botanic Garden ◽  
Tree Fern ◽  
Additional Specimen ◽  
Air Temperatures ◽  
Tree Ferns ◽  
Insulation Effect ◽  
Maximum Temperatures ◽  
Heated Glass

Ten plants of six species of tree fern were trialled for frost hardiness during the winter of 2005/06 when they were planted outdoors in the ground of an interior courtyard at the Royal Botanic Garden Edinburgh. The species were Culcita macrocarpa, Cyathea dealbata, Cyathea dregei,Cyathea smithii, Dicksonia antarctica and Thyrsopteris elegans. An additional specimen of C. dregei was planted in the main garden. The apex region of each tree fern was fitted with an electric thermometer probe to record weekly minimum and maximum temperatures. These were compared with the air temperatures of the courtyard. For thermal insulation, the trunks and crowns of the three Cyathea species were encased in straw. The prostrate rhizomes of C. macrocarpa and T. elegans were covered respectively with leaf litter, straw and a polystyrene tile. As comparators, three trunked specimens of D. antarctica were given no winter wrapping, since previous experience had shown it to be unnecessary. All ten plants survived the winter of 2005/06 which was colder than average, and put out new growth the following spring. Fronds of D. antarctica and C. macrocarpa stayed green; the fronds of the other species were withered by the coldest exposures when the air temperature reached 4.7°C.Compared with the main botanic garden, the courtyard provided a relatively mild microclimate. It was on average 2.5 °C warmer than the air temperature measured in the screen of the main garden weather station, and 7.7°C warmer than the ‘grass’ temperature in the main garden, which went down to –13°C at its lowest. All tree fern apices registered sub-zero temperatures, the range in different plants being from –0.3 to –3.4°C. The apex regions did not get as cold as the surrounding air temperature, which ranged between 0.5 and 2.3°C. The three D. antarctica (without added insulation) had minimum apical temperatures in the same range as the species that were wrapped for the winter. The insulation effect in the apex regions was also shown by the weekly maximum temperatures, which on average were lower than those of the courtyard air maxima.In conclusion, the combination of the locally favourable microclimate of the courtyard, plus appropriate trunk and crown insulation provided for some species, allowed the planting outdoors, of tree ferns normally grown in Edinburgh under heated glass.

scholarly journals Tree Fern Apical Temperatures at the Royal Botanic Garden Edinburgh

2005 ◽  
pp. 17-26
Author(s):  
Alastair Wardlaw ◽  
Louise Galloway ◽  
Andrew Ensoll
Keyword(s):  
Freezing Point ◽  
Ground Level ◽  
Royal Botanic Garden ◽  
Maximum Temperature ◽  
Weather Station ◽  
Botanic Garden ◽  
Tree Fern ◽  
The North ◽  
Thermal Insulating ◽  
Tree Ferns

Tree ferns are difficult to maintain out of doors in the British Isles except in western localities, where winter temperatures are moderated by the North Atlantic Drift, or in places where buildings provide a clement microclimate. The present study of tree-fern apical temperatures during winter was carried out on five trunked specimens of Dicksonia antarctica that had been grown satisfactorily out of doors for several years, while planted in the ground of a courtyard at the Royal Botanic Garden Edinburgh (RBGE). The plants were never wrapped or otherwise protected with thermal insulation during the winter months. An electric thermometer was inserted into the apical cleft of each plant in November 2003, and weekly readings of minimum and maximum temperature taken until April 2004. The ambient temperature of the air in the courtyard was similarly recorded and compared with the screen and grass temperatures at the RBGE weather station in the main botanic garden. The lowest grass and screen temperatures were respectively -11.2°C and -7.1°C, whereas the lowest courtyard and fern-apical temperatures were respectively -3.2°C and -0.8°C. Thus in the coldest period of that winter there was over 10°C difference in temperature between ground level in the main garden and a tree fern apical cleft in the sheltered courtyard. The tree ferns were not noticeably damaged by exposure of the apical cleft region to just below freezing point on a few occasions and the fronds stayed green. The five individual plants differed considerably in trunk height, diameter and volume. Regression analysis revealed that there was a significantly increasing thermal-insulating effect in the apical cleft associated with larger trunk diameters and volumes. The RBGE weather station temperatures during the winter of 2003-4 were unexceptional when compared with records from the previous 19 years. Thus the data from 2003-4 may be taken as representing a typical recent winter for this Edinburgh location. This study highlights the benefits of having detailed temperature measurements when assessing the winter-protective capabilities of a particular micro—environment for a semi-hardy species such as D. antarctica.

scholarly journals Analyses of the Zagreb Grič observatory air temperatures indices for the period 1881 to 2017

2018 ◽  
pp. 67-85 ◽  
Author(s):  
Ognjen Bonacci ◽  
Tanja Roje Bonacci
Keyword(s):  
Time Series ◽  
Air Temperature ◽  
Partial Sums ◽  
Daily Maximum ◽  
Absolute Maximum ◽  
Absolute Minimum ◽  
Air Temperatures ◽  
Temperature Regimes ◽  
Urban Heat ◽  
Maximum Temperatures

The paper studies time series of characteristic (minimum, mean, and maximum) daily, monthly, and yearly air temperatures measured at the Zagreb Grič Observatory in the period from 1 Jan. 1881 to 31 Dec. 2017. The following five air temperatures indices (ATI) are analysed: (1) absolute minimum yearly, monthly, and daily; (2) mean yearly, monthly, and daily minimum; (3) average mean yearly, monthly, and daily; (4) mean yearly, monthly, and daily maximum; (5) absolute maximum yearly, monthly, and daily. Methods of Rescaled Adjusted Partial Sums (RAPS), regression and correlation analyses, F-tests, and t-tests are used in order to describe changes in air temperature regimes over 137 years. Using the RAPS method the five analysed yearly ATI time series durations of 137 years were divided into two sub-periods. The analyses made in this paper showed that warming of minimum air temperatures started in 1970, mean air temperatures in 1988, and maximum air temperatures in 1998. Results of t-tests show an extreme statistically significant jump in the average air-temperature values in the second (recent time) sub-periods. Results of the t-tests of monthly temperatures show statistically significant differences between practically all five pairs (except in two cases) of analysed monthly ATI subseries for the period from January to August. From September to December the differences for most of pairs (except in six cases) of the analysed monthly ATI subseries are not statistically significant. It can be concluded that the urban heat island influenced the increase in recent temperatures more strongly than global warming. It seems that urbanisation firstly and chiefly influenced the minimum temperatures, as well as that Zagreb’s urbanisation had a bigger impact on minimum temperatures than on maximums. Increasing trend in time series of maximum temperatures started 20 years later.

Isaac Bayley Balfour, Sphagnum moss, and the Great War (1914–1918)

2015 ◽  
Vol 42 (1) ◽  
pp. 1-9 ◽  
Author(s):  
P. G. Ayres
Keyword(s):  
United States ◽  
Academic Career ◽  
The United States ◽  
Royal Botanic Garden ◽  
Wound Dressings ◽  
Sphagnum Moss ◽  
Botanic Garden ◽  
Working Model ◽  
Sphagnum Bog ◽  
The Great War

Isaac Bayley Balfour was a systematist specializing in Sino-Himalayan plants. He enjoyed a long and exceptionally distinguished academic career yet he was knighted, in 1920, “for services in connection with the war”. Together with an Edinburgh surgeon, Charles Cathcart, he had discovered in 1914 something well known to German doctors; dried Sphagnum (bog moss) makes highly absorptive, antiseptic wound dressings. Balfour directed the expertise and resources of the Royal Botanic Garden, Edinburgh (of which he was Keeper), towards the identification of the most useful Sphagnum species in Britain and the production of leaflets telling collectors where to find the moss in Scotland. By 1918 over one million such dressings were used by British hospitals each month. Cathcart's Edinburgh organisation, which received moss before making it into dressings, proved a working model soon adopted in Ireland, and later in both Canada and the United States.

On the dynamics of distribution of the American White Butterfly, Hyphantria cunea Drury, 1973 (Lepidoptera, Arctiidae), in Ukraine regarding the annual minimal air temperatures

2018 ◽  
Vol 14 (1) ◽  
pp. 44-57
Author(s):  
S. N. Shumov
Keyword(s):  
Air Temperature ◽  
Annual Reports ◽  
Complete Elimination ◽  
Hyphantria Cunea ◽  
White American ◽  
Gis Technologies ◽  
Data Analyses ◽  
Air Temperatures ◽  
Negative Temperatures

The spatial analysis of distribution and quantity of Hyphantria cunea Drury, 1973 across Ukraine since 1952 till 2016 regarding the values of annual absolute temperatures of ground air is performed using the Gis-technologies. The long-term pest dissemination data (Annual reports…, 1951–1985; Surveys of the distribution of quarantine pests ..., 1986–2017) and meteorological information (Meteorological Yearbooks of air temperature the surface layer of the atmosphere in Ukraine for the period 1951-2016; Branch State of the Hydrometeorological Service at the Central Geophysical Observatory of the Ministry for Emergencies) were used in the present research. The values of boundary negative temperatures of winter diapause of Hyphantria cunea, that unable the development of species’ subsequent generation, are received. Data analyses suggests almost complete elimination of winter diapausing individuals of White American Butterfly (especially pupae) under the air temperature of −32°С. Because of arising questions on the time of action of absolute minimal air temperatures, it is necessary to ascertain the boundary negative temperatures of winter diapause for White American Butterfly. It is also necessary to perform the more detailed research of a corresponding biological material with application to the freezing technics, giving temperature up to −50°С, with the subsequent analysis of the received results by the punched-analysis.

Data Capture Project at the Royal Botanic Garden Edinburgh

2009 ◽  
pp. 77-82
Author(s):  
Natacha Frachon ◽  
Martin Gardner ◽  
David Rae
Keyword(s):  
Genetic Resources ◽  
Research Community ◽  
Royal Botanic Garden ◽  
Data Capture ◽  
Plant Biodiversity ◽  
Botanic Gardens ◽  
Botanic Garden ◽  
The World ◽  
Plant Collections ◽  
Field Notes

Botanic gardens, with their large holdings of living plants collected from around the world, are important guardians of plant biodiversity, but acquiring and curating these genetic resources is enormously expensive. For these reasons it is crucial that botanic gardens document and curate their collections in order to gain the greatest benefit from the plants in their care. Great priority is given to making detailed field notes and the process of documentation is often continued during the plants formative years when being propagated. However, for the large majority of plants this process often stops once the material is planted in its final garden location. The Data Capture Project at the Royal Botanic Garden Edinburgh is an attempt to document specific aspects of the plant collections so that the information captured can be of use to the research community even after the plants have died.

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