Grazing response- A "thorny" issue

[Tony Croft aka hamadryad]

Im so sick of thorns, so sick of them that whilst clearing up a hawthorn hedge we was working, re working i got to thinking, we all know trees with thorns, or prickly habits get more thorny the more they are grazed or pruned. Its an adaption, but, if pruning causes the reponse, i wonder if we could isolate the hormone/chemical and prevent its production prior or after pruning operations.

 

an interesting project for a man whos into researching this kind of stuff, not my bag, but anyone got any ideas?

[armchairarborist]

i did a presentation on antiherbivore adaptation at college and think that this qualifies me to put my stamp on this thread, thats all i've got:blushing:, isnt it usually horticulturalists who mess with plant traits and get a cross with no thorns/more thorns etc, not sure if everytime it gets pruned/bitten/wounded it reprotects itself so how to change that is a tricky one, im a big fan of thorny security hedging, you know - the thick, closely planted stuff that nobody can wriggle through because its planted in 3 or 4 rows of mixed berberis/blackthorn/hawthorn etc..

[Tony Croft aka hamadryad]

trees DO most definatley respond to grazing/pruning by becoming increasingly thorny, holly is a classic example, the higher you go, the less points have the leaves, hawthorns develop thorn side branches to develop thorns on thier thorns in response to being grazed or hedged and an accacia on the wild plains of africa, will not waste resources on putting down wood to form thorns in the centre of its higher canopy as protection is not needed there.

 

so, there MUST be some chemical reaction within trees that is produced from grazing/pruning in order to generate a response that is cleary localised and obvious

[Stephen Blair]

so you want to mess with nature:sneaky2:, not happy with hacking it to bits, you want to take away its form of defense and decrease a safe habitat for hedgerow birds so you do not get jaggy hands?

Tony i am sitting here feeling quite sick

[nepia]

Im so sick of thorns, so sick of them that whilst clearing up a hawthorn hedge we was working, re working i got to thinking, we all know trees with thorns, or prickly habits get more thorny the more they are grazed or pruned. Its an adaption, but, if pruning causes the reponse, i wonder if we could isolate the hormone/chemical and prevent its production prior or after pruning operations.

 

an interesting project for a man whos into researching this kind of stuff, not my bag, but anyone got any ideas?

 

Thorns are surely just modified stems so if you remove the apical dominance by nibbling it off you boost the lateral growth production. No nibbles in the centre of the acacia = little lateral growth.

 

Too simples?

[Ben90]

Worst hawthorns I have ever felled are on sailsbury plain. Their long exposed life of being flailed by tractors, nibbled by animals and shelled by tanks has made them the most bad-ass thorns in existence.

 

Fire usually works. Failing that, use super thick gloves and be careful with each piece that you pick up, twisting as you grip to snap the thorn.

[Bundle 2]

Not strictly thorns but I would venture to suggest ( Ill get shot down now for my ignorance and optimism no doubt)...well. Look at it this way. Thorns are adaptations to survival ( grazing? ).....Self coppicing is a trait shared by many tree species the world over...but not all. For reference here I'd tell you to look at O.Rackhams "Woodlands" ( ch 3,4 & 5)

Here you will find some kind of explanation for the retention of these traits...and whilst they are largely outdated from the survival logic that is applied to their development and success perhaps; they persist.

This may not be quite so much the case with thorns and you will understand this as you read the chapters I mentioned. I recommend anyone to this book.

Thank fook for thorns I say...The relative biodiversity of our landscape owes much to the protection garnered from thorns....

[Tony Croft aka hamadryad]

Thank fook for thorns I say...The relative biodiversity of our landscape owes much to the protection garnered from thorns....

 

when youve spent 20 odd years of your life extracting every species of thorn from your hands you will start to appreciate the fine point of discouraging the formations!

 

My particular fave is the pyracantha, big sturdy thorns that even leaving your body intact and not remaining in your flesh leave a soreness that lasts a day or so!

 

oh and the cockspur hawthorn, spikes to rival any palisade!

 

I think there is a market for a thornless thorn!

[Tony Croft aka hamadryad]

though I guess i should be gratefull i am not an ostrich, have you seen the thorny plant that is designed to clamp thier feet for transport!

 

evolutionary spawn of satan!

[Saw-sick Steve]

trees DO most definatley respond to grazing/pruning by becoming increasingly thorny

 

so, there MUST be some chemical reaction within trees that is produced from grazing/pruning in order to generate a response that is cleary localised and obvious

Interesting theory, not sure if it applies universally though, otherwise why would trees like the Lancewood in New Zealand still grow in a manner designed to deter browsing by Moas - centuries after Moa became extinct?

One often overlooked fact about our native thorns is their importance as 'nurseries' for less browse resistant climax species in semi-natural landscapes. Thick. impenetrable clumps of (especially) Blackthorn often protect the odd Oak or Beech from damage until they have got well established.