Author Topic: Thornless youngberry getting thorns?  (Read 147 times)

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Offline Mukluk

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Thornless youngberry getting thorns?
« on: January 27, 2018, 05:26:05 PM »
In winter I bought a thornless youngberry.  It is growing well but I am worried that it may be getting thorns? 

It started that the backs of the leaves furthest from the roots started to get hairs where the prickles would normally be.  Then the hairs started to get more course and curved.  Then as the cane grew longer it has started to get these hairs too.  Now some of these look as though they may start to turn into prickles as they age.

This is not a plant grown from a seed that has dropped, or a sucker that has arisen from the roots, it is the same cane, just further along.  The cane and the leaves lower down have absolutely no prickles or hairs whatsoever.

What is happening here?  Is this normal for thornless youngberry and these hairs will not turn into actual prickles?  Or is it likely that next year I will just have a thorny plant?

Offline Raymondo

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  • Northern Tablelands, N.S.W.
Re: Thornless youngberry getting thorns?
« Reply #1 on: January 27, 2018, 08:53:27 PM »
Thornless brambles are often the result of a type of mutation called a chimeric mutation. It is localised in the plant. Sounds like the chimera has reverted at a point along the branch. Trim off the thorny bits. New buds emerging along the thornless lower part should also be thornless. That’s the theory anyway.
Ray, gardening on an old flood plain with clay loam from 30 to 60 cm deep over clay.

Offline Mukluk

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Re: Thornless youngberry getting thorns?
« Reply #2 on: February 03, 2018, 08:33:32 PM »
Thanks Ray,

I know that there are several forms of thornlessness in brambles.  There is true genetic thornless, which this clearly isn't.  Then there is periclinal chimera thornless, which is thornless only in the epidermal layer of cells.  They are known for sending up thorny canes if the root is damaged.  This doesn't really seem to fit either.

I find the fact that the cane is thornless at the base and gradually gets thorny the higher up it goes to be perplexing.  The lower part of the cane is completely thornless.  Do you think that new canes produced in spring will likely be thornless? 

I only chose thornless youngberries because I didn't want to deal with prickles.  Had I thought it would have turned thorny so easily I may have reconsidered what type of berry to grow.  Then again, they are utterly delicious so perhaps I still would have chosen it.

Offline Raymondo

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  • Northern Tablelands, N.S.W.
Re: Thornless youngberry getting thorns?
« Reply #3 on: February 04, 2018, 02:27:29 PM »
I don’t know what is likely to happen. Wait and see is about the best I can offer. We have a thornless loganberry that isn’t, though it’s not as prickly as its boysenberry neighbour! I would love a thornless boysenberry as it is my favourite bramble. I like them enough though to put up with scratches.
Ray, gardening on an old flood plain with clay loam from 30 to 60 cm deep over clay.