Plant ID Portfolio - some final notes

The posts with the "plant id' label constitute my Plant Portfolio for the Plant Identification and Classification module on year one of my BSc of horticulture studies at ITB.

This turned out to be quite an undertaking, as I checked the RHS A-Z Encyclopedia of Garden Plants for each one of the plants - as well as my 1998 copy of Hillier's for all trees and shrubs (see Bibliography). The final descriptions and cultivation notes are based on those, and my lecture notes.

The sizes are as listed on the Encyclopedia and refer to mature plants - though it's well worth keeping in mind that in many parts of Ireland the growing conditions are sufficiently better for the ultimate size of many plants to be remarkably larger from the one listed, even in an "average" location.

I've also included additional notes on various topics for a smattering of plants, mostly out of my own interest.


Observations and reflection:

While the required 120+ plants only scrape the bloom of the surface of the continuously growing number of garden plants in cultivation, I've noticed that I'm already able to identify the vast majority of the shrubs and hedges I see anywhere I go. This, however, says a lot more about the variety of plants people go for (and/or garden centres sell!) than my abilities or knowledge level.

In any case, it's already obvious that there's nigh unlimited scope for educating the plant purchasing public to broaden their tastes. Perhaps the impending and encroaching climate change will help there, making consumers more open to new solutions.

I think the blog approach was probably the right one. The process was slower than I expected (all that leafing through books turned out to consume a lot of time!), and I did learn a lot as I went along. I haven't yet fully utilised all the features the medium offers; I haven't, for example, linked to external pages with more information for most plants. On the other hand, adding material in the future will be easy - as well as finding all this information! It won't languish at the bottom of a bookshelf but can be accessed from anywhere.

Plant ID - Bibliography

Bibliography

Beazley, M. (2002) The Royal Horticultural Society Essential Gardening Techniques. London: Octopus Publishing Group Limited.

Brickell, C. ed. (1996) The Royal Horticultural Society A-Z Encyclopedia of Garden Plants. London: Dorling Kindersley Limited.

Brickell, C. ed. (2006) The Royal Horticultural Society Gardeners’ Encyclopedia of Plants & Flowers. 4th Ed., London: Dorling Kindersley Limited.

Flora Europaea Search Results (2011) [online] Edinburgh, Royal Botanic Garden Edinburgh. Available from: http://rbg-web2.rbge.org.uk/cgi-bin/nph-readbtree.pl/feout?FAMILY_XREF=&GENUS_XREF=Primula+&SPECIES_XREF=vulgaris&TAXON_NAME_XREF=&RANK= [Accessed: 26th Nov 2012].

Grounds, R. (1998) The Plantfinder’s Guide to Ornamental Grasses. Newton Abbot, Devon, England: David & Charles Publishers.

Hessayon, D. (1983) The Tree & Shrub Expert. Waltham Cross, England: pbi Publications.

Hillier, J and Coombes, A. eds (2004) The Hillier Manual of Trees & Shrubs. Newton Abbot, Devon, England: David & Charles Publishers.

Hillier Nurseries (1998) The Hillier Manual of Trees & Shrubs Pocket Edition. Newton Abbot, Devon, England: David & Charles Publishers.

Hughes, G. ed. (1996)  A Step-by-Step Guide to Creating a Kitchen Garden. Godalming, Surrey, England: Colour Library Books Ltd.

Key, H. (1997) Ivies - A Wisley Handbook. London: Cassell Educational Limited.

Lipanovich, M. ed. (2002) Landscaping with Ornamental Grasses. Menlo Park, California: Sunset Books Corporation.

Plants (2012) [online] London, The Royal Horticultural Society. Available from: http://www.rhs.org.uk/Plants. [Accessed multiple times].


NB: This bibliography does not include the resources linked to from the individual posts.

Additional images for Plant ID

Choisya ternata blooming in a park in Glasnevin.

My plant ID test nemesis, Elaeagnus x ebbingei.

The delightful autumn colour of a
 Cotoneaster horizontalis.

Aucuba japonica

Prunus laurocerasus 'Otto Luyken' does not
look like its "big brother" P. laurocerasus.

Prunus laurocerasus 'Otto Luyken' in park, badly
maintained and poorly (note chlorotic leaves).

Stipa tenuissima 'Pony Tails'
(source)

Fatsia japonica in bloom at Dublin Zoo

Fatsia japonica

Viburnum tinus 'Eve Price' in bloom
in December.

I wanted to make a whole separate post on trees, but ended up spending my afternoon worm wrangling instead. Here's a picture of the avenue length of the North Circular Road, with the vista carefully aimed at the Wellington Monument in the distance. This is the kind of thing I worry about replacing - will the future city horticulturists follow the footsteps of their Victorian forebears when the time comes, or just give up?

The trees are probably Platanus x acerifolia.

And finally another tree not included in our lists, but one I particularly like: Garrya elliptica:

It stays relatively small and isn't particularly demanding, making it a perfect plant for modern urban and Celtic Tiger housing estate gardens.

...which reminds me that I'm also fond of the smaller Sorbus spp. and vars, especially those in the Aucuparia section [Hillier 1998] with their delicate-looking pinnate leaves and variety of berry colours. Something like Sorbus vilmorinii is definitely on my "one day when" list.

Plant ID Week 8: Winter twig identification

The very last Plant ID session was on winter twig identification. When identifying trees and shrubs not in leaf, one has to rely on other features for identification, such as the colour, texture, size and positioning of buds, bark colour, twig shape and structure and so on. Once you know what to look at, twigs that looked very similar will resolve to look quite distinctive.

The Woodland Trust have an excellent twig identification sheet which can be downloaded from here. It covers all our twigs barring Malus sylvestris, and the below images are from there (clicking on an image lets you view it in full size).

(Field maple (Acer campestre) isn't on our list)

Note catkins on alder (Alnus glutinosa)
and hazel (Corylus avellana).

Note difference in hawthorn (Crataegus monogyna)
 and blackthorn (Prunus spinosa) bark texture.

Here's our full list of winter twigs, with identification information:

Malus sylvestris twigs. Note the abruptly finishing shoots.
(Source)

Tilia x europaea bud detail. Note the mitten-like shape.

Aesculus hippocastanum twig detail showing
the horseshoe shaped leaf scar.

Reflection:
There are a large number of online winter twig identification keys of various quality and usability. If choosing to use one, you should first of all check where in the world it applies to - a North American key would be of limited use in Ireland. Additionally in the horticultural trade we're not limited to native and naturalised trees, but will also need be able to distinguish any number of deciduous shrubs around the year. Here experience will be the best teacher.

One last thing to keep in mind is to not just look at the tips of twigs when identifying a deciduous specimen: the shape and general habit of the tree can be as important an identifying feature. For example, I'm reasonably sure these are Carpinus betulus 'Fastigiata', the upright elm, a popular modern street tree, just by their shape.

Plant ID Week 1: Weeds

The very first full Plant ID practical session was on weeds. Here are some images, with links to a plethora of information from Garden Organic at the UK.

Ranunculus repens, creeping buttercup.
More information here.

Red deadnettle information here, coltsfoot here.
 P. major here.

Poa annua, more on which herewith.

A Sonchus sp and Senecio jacobea,
 the common ragwort.

Stinging nettle, Urtica dioica.

Broad-leaved dock, Rumex obtusifolius. The other common
dock is the curled dock, R. crispus.
Dock seeds can survive in soil for 50 years. Fifty. Years.

Pineappleweed, Matricaria discoidea. Does
indeed sort of smell of pineapple.

Not chickweed (Stellaria media). Knotweed, Polygonum sp.

Information here.

Spear thistle, detail.

The common mouse-ear, Cerastium fontanum

My "favourite", hah, weed is now couch grass, Elymus repens. I used to consider the creeping buttercup ("sprinting buttercup", my mother-in-law says) my nemesis, but have since acquired a garden half of which was completely overrun by couch. I don't expect ever to win that war, but have so far managed to not lose the battles...

Here it is, in all its unassuming glory:

(source)

Looks deceptively meek, doesn't it. Come spring, it'll EAT GLYPHOSATE.

Plant ID Week 2, pt. 2

Second part of the first batch of plants to learn.

Viburnum opulus - guelder rose

(Source)

A large deciduous shrub with white flowers followed by bright red berries. Leaves turn red in the autumn and take their time to fall.
Size: 5x4 m

Cultivation notes:
Shrub; plant November to March, mulch well, water in drought.

Corylus avellana - hazel

Leaves and nuts.
(Source)

C. avellana 'Contorta'.
Note the typical green buds midst of winter.

A small, many-stemmed native tree used for coppicing and nuts. Can give a good autumn colour in a sheltered spot. Yellow "Lamb's tails" catkins in late winter or early spring.
Size: 5x5 m

Cultivation notes:
Tree; plant in a hole 1.5 times the size of the root ball, incorporate organic matter, support and mulch well. Keep well watered until established.

Ilex aquifolium - holly

(Source)

An evergreen native tree with very distinctive shiny foliage. Makes an excellent slow-growing hedge, also in coastal areas, but will grow to an impressive tree if given the chance.
*RHS award of garden merit
Size: up to 25x8 m


Cultivation notes:
Tree; plant in a hole 1.5 times the size of the root ball, incorporate organic matter, support and mulch well. Keep well watered until established.
The holly is dioecious and most cultivars are either male of female. In order for a female plant to produce fruit, it must be pollinated by a male one, which you must have relatively close by (I. aquifolium 'J. C. van Tol' is self pollinating and as such suitable for a small garden).


Betula pendula - silver or common birch

(Source)

A native tree with a high wildlife value and typically yellow autumn colour. Makes for a good pioneer plant, also in light shade, and is thus much-used in new apartment blocks' courtyards.

*RHS award of garden merit
Size: up to 25x10 m


Cultivation notes:
Tree; plant in a hole 1.5 times the size of the root ball, incorporate organic matter, support and mulch well. Keep well watered until established.
Personal note: I got married in a grove of birch trees. :)

Sorbus aucuparia - mountain ash

(Source)

(Source)

A compact tree with spring flowers and ferny foliage, which turns various shades of red in the autumn. The autumn bunches of red berries are much liked by a number of garden birds.
Size: up to 15x7 m

Cultivation notes:
Tree; plant in a hole 1.5 times the size of the root ball, incorporate organic matter, support and mulch well. Keep well watered until established.

Personal note: the rowan is the only significantly flowering and fruit-bearing tree in Northern Finland, and so particularly special.
Observation: S. aucuparia is a wonderful tree, but currently rather overused as a street tree.

Ulex europaeus - gorse, furze

(Source)

A viciously spiny shrub with yellow, almond-scented flowers. Does very well on exposed seaside locations.
Size: up to 2.5 x 2 m

Cultivation notes:
Shrub; plant November to March, mulch well, water in drought.
Plant in poor soil in full sun;  can become leggy in rich soil.

Alnus glutinosa - common or black alder

(Source)

(Source)

A very hardy native tree with pear-shaped glossy leaves that stay on late into the winter. Produces catkins amongst the first trees in the spring (with very allergenic pollen).
Size:25x10 m

Cultivation notes:
Tree; plant in a hole 1.5 times the size of the root ball, incorporate organic matter, support and mulch well. Keep well watered until established.


Prunus insititia - wild damson

(Source)

A thorny native tree with edible fruit. White blossom in the spring
Size: 5x5m

Cultivation notes:
Tree; plant in a hole 1.5 times the size of the root ball, incorporate organic matter, support and mulch well. Keep well watered until established.
Note: not included in Brickell (1996) either as P. insititia or P. domestica ssp. insititia.
Historical note: This forebear of modern plums has been enjoyed since antiquity. Quoth Wikipedia:

"The name damson derives from the Latin prunum damascenum, "plum of Damascus". Damsons were first cultivated in antiquity in the area around the ancient city of Damascus, capital of modern-day Syria, and were introduced into England by the Romans. Remnants of damsons are often found during archaeological digs of ancient Roman camps across England, and ancient writings describe the use of damson skins in the manufacture of purple dye. Prugne damaschine figure in the long list of comestibles enjoyed by the Milanese given by Bonvesin de la Riva in his Marvels of Milan (1288)."

Tilia x europaea - European lime

(Source)

A very popular park and street tree often used for pleaching. Foliage turns yellow in the autumn.

Size: 35x15 m

Cultivation notes:

Tree; plant in a hole 1.5 times the size of the root ball, incorporate organic matter, support and mulch well. Keep well watered until established.

A row of lime trees in December, showing the pleasing
red of younger shoots.

Plant ID Week 2, pt. 1

The first session, second last to post. I've rather belatedly realised that it makes more sense to divide the sets to two, if not three, to make it easier to utilise the search function. So here goes - with very little original photography.

~~

Rosa canina - dog rose, wild rose 

Image source and further information: RHS Plant Selector

A native thorny and vigorous shrub with pink or white flowers and red hips. Most useful as hedging or in wildlife gardens and hedgerows.
Size: 2.5-4 x 1.5-2.5 m

Cultivation notes:
Shrub; Plant November to March, mulch well, water in drought. Manages all aspects and exposed sites.

Acer pseudoplatanus - sycamore

(Source)

A long-naturalised large tree, widely used in landscaping and parklands as it manages exposed locations well. A traditional hedgerow component.
Size: 30x25 m

Cultivation notes:
Trees; plant in a hole 1.5 times the size of the root ball, incorporate organic matter, support and mulch well. Keep well watered until established.
Will grow vigorously in almost any soil, to the point of weediness and is considered an invasive species in parts of North America.

Fraxinus excelsior - ash

Note the distinctive black buds.
(Source)

(Source)

A vigorous native tree, widely used in parklands and exposed locations. The most common tree in Irish hedgerows [source]. Particularly valuable for timber.
*RHS award of garden merit
Size: 30x20 m
Cultivation notes:
Another potentially weedy tree.
Trees; plant in a hole 1.5 times the size of the root ball, incorporate organic matter, support and mulch well. Keep well watered until established.


Rosa rugosa - hedging rose

(Source)

A fiercely prickly deciduous shrub with strongly-perfumed flowers, large hips and colourful foliage in the autumn. Will form dense thickets and is excellent for thorny hedging.
Size: 1-2.5 x 1-2.5 m


Cultivation notes:
Shrub; Plant November to March, mulch well, water in drought. Manages all aspects and exposed sites. Can be invasive.


Hedera helix - ivy

Climbing H. helix

Bushy adult H. helix

Adult form. Note leaf shape and immature berries.

An evergreen native climber which, when mature, provides wildlife with pollen early in the spring and berried in the winter.
Height: 10 m

Cultivation notes:
Prefers limy soil. Green-leaved vars will grow up shaded walls, but variegated forms will need more light.
Botanical note: Ivy grows in two forms. The climbing or trailing juvenile form with the typical leaf shape, and the mature or adult form (see images). An adult ivy becomes bushy and top heavy, starts producing flowers and berries every year, and will no longer climb. The adult form takes over once the ivy has climbed high enough to have lots of light and an open aspect - or has just run out of support. Regular pruning will keep an ivy in the juvenile climber form.

Quercus robur - English or pedunculate oak

Note the way leaves have no stems.

The quintessential native tree of the British Isles. Used as a specimen tree, in parklands and for timber.
*RHS award of garden merit
Size: 35x25 m

Cultivation notes:
Trees; plant in a hole 1.5 times the size of the root ball, incorporate organic matter, support and mulch well. Keep well watered until established.
Relatively slow-growing and very long-lived.
Taxonomical notes: can most easily be identified from Q. petraea by its sessile leaves and pedunculate acorns. There's a bewildering array of oak species in cultivation as this image from the RHS Encyclopedia of Garden Plants demonstrates.

Source: Brickell, 1996 p. 855.

Quercus petraea  - sessile oak

Note the stems on the dead January leaves.

The other native oak; landscape uses as Q. robur, but suits maritime situations better.

*RHS award of garden merit
Size: 30x25 m



Cultivation notes:
Trees; plant in a hole 1.5 times the size of the root ball, incorporate organic matter, support and mulch well. Keep well watered until established.
Taxonomical note: can most easily be identified from Q. robur by its long-stalked leaves and stalkless acorns.


Symphoricarpos albus laevigatus - snowberry

(Source)

A dense, deciduous shrub producing an abundance of large, white glistening berries for the autumn. An excellent hedging plant that is ideal for poor soils or shady, dark corners. Also good for shelter or game cover.
Size: 2x2 m


Cultivation notes:
Shrub; Plant November to March, mulch well, water in drought.



Prunus spinosa - blackthorn, sloe

(Source)

A native hedgerow shrub or small tree that carries spring blossom on bare branches in spring time. Autumn sloes can be used in preserves or flavoring gin.
Size: 5x4 m

Cultivation notes:
Plant either as a shrub or like a tree as per the general cultivation guidelines, depending on size.





Crataegus monogyna - hawthorn

(Source)

Hawthorn tree in full bloom.
(Source)

Another thorny native of the hedgerows. Produces spring blossom once in leaf and red haws in the autumn. Used extensively for hedging, but can grow into a sizable tree.
Size: 10x8 m

Cultivation notes:
As Prunus spinosa.