A new Phenological Garden at Armagh Observatory

See also: Nature's Calendar Ireland

Introduction

The phases of the annual cycles of certain flora and fauna have been known throughout history to be influenced by climate. Many diaries and garden records from past centuries, including those of Armagh Observatory, give dates of phenological events such as bud burst, first flowering and leaf fall as well as the return of migratory birds such as the cuckoo. This type of material can help to provide, not only proxy climate data for periods during which no instrumental records were kept, but also valuable knowledge of how our changing climate is affecting the natural world today.

In the mid-20th century, a series of phenological gardens were set up in Europe with the intention of employing observations of certain common species of plants as indicators of climate change. They used genetically identical material provided by a central coordinating laboratory in Germany. Four such gardens were established in Ireland at: Valentia Observatory, Co Kerry, The JFK Arboretum, Co Wexford, Johnstown Castle, Co Wexford, and the Botanic Gardens, Dublin. Only one or two such gardens were established in Great Britain at that time and none in Northern Ireland.

Why Armagh?

In order to relate the phenological data with climate change, it is essential that a nearby meteorological station exists which can provide information on local environmental variables such as precipitation, temperature, sunshine and humidity. Armagh Observatory, which has the longest (209 years) such climate record in Ireland and one of the longest in the UK, is a prime location for such a garden. The establishment of a garden in Armagh will provide a valuable addition to the current Irish network, and, in association with exhibits at the Observatory, Planetarium/Eartharium and AstroPark, will highlight the importance of climate change, how it has occurred throughout geological history and how it continues to affect our environment.

The Site

We have established a phenological garden in the north-west corner of the Observatory's estate, between the Stone Calendar in the AstroPark and the Observatory Bungalow. This will provide a gently sloping site, similar in many characteristics to the orchard covered drumlins of County Armagh. The site is exposed to the south and west and partially sheltered from the east. It has all the qualities required of a good site for a phenological garden in this area with more than adequate space for several specimens of each of the 15 IPG recommended species as well as other native plants.

The site lies to the west of the Stone Calendar, in the direction of several important vistas relevant to the AstroPark. These include the setting points on the horizon of the Sun at mid-winter solstice, mid- summer solstice and the equinoxes, and dramatic views of the RC and CoI Cathedrals on neighbouring hills in the City of Armagh. The lines of sight of these phenomena and buildings are to be left free of obstruction. Further dramatic views of the RC Cathedral from the Observatory Lane should also not be obscured. Figure 1 shows the position and direction of the important sight lines and where they cross the proposed site.

A grass path (shown in light green), 1-2m wide, will link the three planted blocks. It will connect to the tarmac path around the Stone Calendar, to the garden at the rear of the bungalow and to the car park. This will enable the meteorological observer to make a short detour through the phenological garden from his current daily walk between the met station where the readings are taken and the bungalow where they entered into computer. A second path (shown in brown) with a more moderate slope will be provided for handicapped visitors. The area between the plants and path will be established as a wild flower meadow with the sward cut only once or twice annually and the mown grass removed. No fertiliser or weedkiller will be used in the garden.

The species to be planted

A list of 15 species has been proposed by the IPG which includes a few species native to Ireland. In late March 2004 the IPG Central Coordinating Laboratory at the Humboldt University of Berlin provided clones of 13 species. These have been planted in the northwestern part of the garden. As it may be some time before we are able to obtain the full quota of suitable cloned specimens, we have also planted a selection of native species proposed by Trinity College Botany Department together with some taken from a longer list in the Woodland Trust's booklet "A guide to recording spring and autumn events in Nature's Calendar". The native specimens have been provided by Woodside Nursery, Ashford Co Wicklow and Future Forests, Co Cork

Collaboration with other groups in the Republic of Ireland and on the Continent

This project is being undertaken in association with Drs A.Donnelly and A Caffarra, and Prof. Mike Jones of the Department of Botany, Trinity College, Dublin who have an ongoing research project to study the environmental triggers of tree phenophases. Such studies could be of considerable value for the horticultural and agricultural industries in Ireland, North and South.

We are also indebted to Dr Eoin Moran and Jack O'Sullivan of the Valentia Observatory, Caherceveen, Co Kerry who first gave us the idea to initiate a garden in Armagh. The staff at Valentia Observatory have first hand practical experience of operating such a garden for several decades and have in the past given us help with the calibration of instruments at Armagh.

The data from the phenological garden in Armagh will be passed in a standard format to the central coordinating organisation in Ireland (to be based at the Valentia Observatory), to the Woodland Trust of the United Kingdom, and to the International Phenological Garden Data Centre at the Humbolt University, Berlin.

CJB
Armagh Observatory,
April 2004


Table 1.  Species supplied by the IPG Central Coordinating Laboratory, March 2004

IPG	Species			Common Name

111	Larix decidua		European Larch
122	Picea abies		Norway Spruce	
211	Betula pubesc.		Downy Birch
281	Tilia cordata		Small-leafd Lime	
311	Ribes alpinium		Alpine Currant	
323	Salix acutifolia	Pussy Willow	
324	Salix smithiana		Smiths  Willow	
326	Salix viminalis		Basket Willow	
331	Sambucus nigra		Elder		
411	Corylus avellana	Hazel	
421	Forsythia susp.		Forsythia
431	Syringa vulgaris	Lilac		

	
Table 2. Native Species included in the Pheonological Garden 

1.	Taxus baccata		Yew
2.	Quercus robur		Pedunculate Oak
3.	Ilex aquifolium		Holly
4.	Euonymus europaeus	Spindle
5.	Arbutus unedo		Strawberry Tree
6.	Fraxinus excelsior	Ash
7.	Prunus spinosa		Blackthorn
8.	Crataegus monogyna	Hawthorn
9.	Corylus avellana	Hazel
10.	Viburnum opulus		Guelder Rose
    
_____________________________________________________________________________

      List of Native Species planted at Armagh Observatory in 2004
      
    In order of list supplied by TCD Department of Botany, January 2004      
      
 
NS	English Name	Latin			Irish Grid X	Irish Grid Y 
      
1.	Yew		Taxus baccata		87713		45778          
						87712		45781

2.	Juniper		Juniperus communis	87727		45791
						87724		45791
						87724		45789

3.	Peduncul. Oak	Quercus robur		87708		45788

4.	Holly		Ilex aquifolium		87710		45775
						87707		45773

5.	Spindle		Euonymus europaeus	87729		45794
						87727		45798
	
6.	Strawberry Tr.	Arbutus unedo		87705		45779
						87707		45779

7.	Common Ash	Fraxinus excelsior	87704		45784
						87709		45785

8.	Elm		Ulmus glabra		87700		45796
						87706		45799
						
9. 	Blackthorn	Prunus spinosa		87715		45798
						87713		45792

10.	Hawthorn	Crataegus monognya	87716		45809
						87710		45808
						
11.	Buckthorn	Rhamnus cathartica	Not yet available

12.	Alder buckthorn	Frangula alnus		Not yet available	

13.	Hazel		Corylus avellana	87716		45804
						87712		45803

14. 	Gorse		Ulex europaeus		Not found

15.	Autumn Gorse	Ulex. galli		Not found

16.	Elder		Sambucus nigra		87721		45793

17.	Guelder Rose	Viburnum opulus		87717		45781

18.	Heather		Erica or calluna	Not found

19.	Dogwood		Cornus sanguinea	87720		45787
						87721		45783

20.	Bilberry	Vaccinium myrtillus	Not found

21.	Bog Myrtle	Myrica gale		87740		45801

	
Also:

	Rowan(?)				87744		45799

Last Revised: 2009 November 5th