Thursday, 13 March 2014

Week 43: Blackthorn (‘Prunus spinosa’)

Blackthorn was @SpeciesofUK from 9th to 22nd December, 2013.

The blackthorn is a small deciduous tree native to the UK and indeed most of Europe.[1] It is known for its blue-black fruits called ‘sloes.’

Blackthorn can be found growing both naturally and in planted hedges.

Blackthorn is perhaps best known as an excellent hedging plant. It provides a tough, thorny, animal-proof boundary that can cope with most soils.[2]

Blackthorn Hedge
[Flickr Creative Commons © Sorbus sapiens]

An even stronger blackthorn hedge can be made by 'pleaching,' interweaving living and dead branches.

Pleaching Blackthorn
[Flickr Creative Commons © CaptainOates]

As well as being used in hedges, blackthorn is a natively-growing UK plant and it occurs naturally in scrub, copses and woodlands.[3]

Blackthorn is spiny, but pretty!

The dark brown bark of blackthorn is smooth, but its twigs form perpendicular shoots, which develop into thorns. It's also densely branched, making it nigh-on impenetrable.[4]

Thorny Blackthorn
[Flickr Creative Commons © the incredible how]

A Blackthorn Thorn
[Flickr Creative Commons © John Tann]

Mature blackthorn trees can grow to a height of around six or seven metres and can live for up to a hundred years.[5]

A Tall-growing Blackthorn
[Flickr Creative Commons © Tio Noi]

Blackthorn leaves are slightly wrinkled, oval, toothed, pointed at the tip and tapered at the base.[6]

Blackthorn Leaf in Autumn
[Flickr Creative Commons © anemoneprojectors]

Blackthorn is hermaphroditic, meaning both male and female reproductive parts are found in one flower.[7] The flowers are white and appear on short stalks before the leaves in March or April, singularly or in pairs.[8]

Blackthorn Flower
[Flickr Creative Commons © --Tico--]

The blossom is most spectacular in years where a false spring is followed by a very cold snap. These are called ‘blackthorn winters’.[9]

Blackthorn Blossoms
[Flickr Creative Commons © .Bambo.]

But the loveliest thing about blackthorn is its fruit.

Once pollinated by insects, blackthorn flowers develop into blue-black fruits measuring 1.5cm across. These are the famous 'sloes.'[10]

Sloes
[Flickr Creative Commons © Alexandre Dulaunoy]

Sloes are used for wine making and preserves and, most commonly, flavouring sloe gin.[11] Sloe gin is a red liqueur flavoured with sloes which has a high sugar content. It originates in the UK![12]
It’s best to use ripe sloes, traditionally picked after the first frost (late October to early November).[13]  A half bottle of sloes is mixed with half their weight again in sugar and the bottle filled with gin, before being left for two months and then strained.[14]

Sloe Gin
[Flickr Creative Commons © Denni Schnapp]

In addition to flavouring gin, sloes are used in jellies, conserves and syrups, and have various uses in folk medicine.[15]
The flowers of blackthorn are also edible, while the leaves have been dried and used as a substitute for tea.[16]

It's possible to confuse blackthorn with hawthorn.

Both plants are from the Rosaceae 'rose' family, and they are both very thorny. However there are several key differences.[17]

1. Blackthorn has oval, tapered leaves, whereas hawthorn has distinctive small, lobed leaves.[18]

Hawthorn Leaves
[Flickr Creative Commons © nz_willowherb]

2. Blackthorn thorns are noticeably longer than hawthorn, and the plant is more messy-looking and dense overall.[19]

3. Blackthorn flowers appear before the leaves, whereas hawthorn flowers appear after.[20]

4. The fruits are completely different. Haws from hawthorn are red, and sloes from blackthorn are blue.[21]
Blackthorn hedgerows provide a great habitat to many other species.

Because blackthorn flowers quite early, it provides a valuable source of nectar and pollen for bees in spring.[22]

Blackthorn foliage is a food plant for the caterpillars of moths such as the lackey, magpie, common emerald, small swallow-tailed and yellow-tailed.[23] Moths also take advantage of the blossoms as a source of nectar.

Small Quaker Moth on Blackthorn
[Flickr Creative Commons © Sinkha63]

Blackthorn has a particularly close relationship with the brown hairstreak butterfly, which returns to blackthorn in late August to lay its eggs.[24] The eggs overwinter and hatch in spring when the buds are breaking.[25]

Brown Hairstreak Laying Egg on Blackthorn
[Flickr Creative Commons © oldbilluk]

Birds such as nightingales nest among dense, thorny blackthorn thickets, eating caterpillars and other insects from the leaves. Then they feast on the berries in autumn.[26]

Blackthorn timber is hardwearing and tough.

The wood from blackthorn was traditionally used to make walking sticks, tool parts and riding sticks.[27]

Blackthorn was the traditional wood for Irish shillelaghs - clubs/walking sticks that were used to settle disputes in a gentlemanly manner.[28]

Assorted Shillelagh
[Wikimedia Commons © Samuraiantiqueworld]

Strange but true…

Blackthorn has long been associated with witchcraft, and it is said that witches' wands and staffs are made from blackthorn wood.[29]



[1] http://www.woodlandtrust.org.uk/learn/british-trees/native-trees/blackthorn/
[2] http://www.ashridgetrees.co.uk/hedging-plants-trees-shrubs-bareroot/native-hedging/blackthorn-sloe-prunus-spinosa
[3] http://www.woodlandtrust.org.uk/learn/british-trees/native-trees/blackthorn/
[4] http://www.woodlandtrust.org.uk/learn/british-trees/native-trees/blackthorn/
[5] http://www.woodlandtrust.org.uk/learn/british-trees/native-trees/blackthorn/
[6] http://www.woodlandtrust.org.uk/learn/british-trees/native-trees/blackthorn/
[7] http://www.woodlandtrust.org.uk/learn/british-trees/native-trees/blackthorn/
[8] http://www.woodlandtrust.org.uk/learn/british-trees/native-trees/blackthorn/
[10] http://www.woodlandtrust.org.uk/learn/british-trees/native-trees/blackthorn/
[17] http://www.skillsforwildlives.com/2010/06/blackthorn-vs-hawthorn-an-identification-guide/
[18] http://www.skillsforwildlives.com/2010/06/blackthorn-vs-hawthorn-an-identification-guide/
[19] http://www.skillsforwildlives.com/2010/06/blackthorn-vs-hawthorn-an-identification-guide/
[20] http://www.skillsforwildlives.com/2010/06/blackthorn-vs-hawthorn-an-identification-guide/
[21] http://www.skillsforwildlives.com/2010/06/blackthorn-vs-hawthorn-an-identification-guide/
[22] http://www.woodlandtrust.org.uk/learn/british-trees/native-trees/blackthorn/
[23] http://www.woodlandtrust.org.uk/learn/british-trees/native-trees/blackthorn/
[24] http://en.m.wikipedia.org/wiki/Brown_Hairstreak
[25] http://en.m.wikipedia.org/wiki/Brown_Hairstreak
[27] http://www.woodlandtrust.org.uk/learn/british-trees/native-trees/blackthorn/

No comments:

Post a Comment