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Dahlia question

Just lifting some dahlias and one has this growing around the top but the rest of the tuber looks ok. What is it and should I keep it?

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  • Pete.8Pete.8 Billericay, EssexPosts: 9,863
    I'd guess it's a Crown Gall - but that's just a guess as I've not had any experience of it.
    If it is, the plant should be destroyed.
    But see what others think first :)
    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
  • I've had something similar on my dahlias in the past and have destroyed them. It definitely looks like gall.Get rid.
  • mac12mac12 Posts: 150
    I've googled what you've both said and think you're right. Will I be able to plant in the same place again 
  • Pete.8Pete.8 Billericay, EssexPosts: 9,863
    It's not something I have any experience of, but came across this article that seems to indicate the bacteria that cause it can remain viable in the soil for up to 2 years.

    '2. Destroy infected plants. Destroy the infected plant. The bacterium will remain in the soil so it is important to plant a resistant plant species. If the same species needs to be planted in the area, remove and replace the soil or consider soil sterilization.

    Life Cycle

    Crown gall forming bacteria inhabit the soil and survive for many years. The bacterium can initially be brought in on the roots of infected plants. It then spreads by soil and water movement or contaminated pruning tools. Bacteria enter the plant through wounds possibly caused by chewing insects, cultivation damage, or from grafting and pruning tools. The crown gall bacterium has been known to survive more than two years in the soil in the absence of susceptible plants. It can live for several years in decomposing galls buried in the soil. Crown gall is likely to be more serious in limed soil than in acid soils so soil pH could be important in limiting the disease.


    From-
    https://www.missouribotanicalgarden.org/gardens-gardening/your-garden/help-for-the-home-gardener/advice-tips-resources/pests-and-problems/diseases/bacterial-galls/crown-galls
    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
  • mac12mac12 Posts: 150
    Thanks for that information I grow about 50 in a raised bed so I'll have to find somewhere else to plant them and decide what to put in the raised bed 
  • Pete.8Pete.8 Billericay, EssexPosts: 9,863
    Oh dear..
    I wish I had a solution for you.
    I suppose you could leave a few in that area but away from the problem area and see how they fare next year.
    I don't know how far the problem area may extend, so maybe remove some of the soil in that area and see how things go..
    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
  • FairygirlFairygirl west central ScotlandPosts: 49,086
    What a shame @mac12
    I don't know if you can safely take cuttings from those? Maybe someone knows the answer to that, but if you've cut them back, it would be too late anyway.  :/
    It's a place where beautiful isn't enough of a word....


  • Pete.8Pete.8 Billericay, EssexPosts: 9,863
    Apparently not I'm afraid according to this

    The bacteria are not known to become systemic within a plant. One question then, is whether a grower can take cuttings of branches or shoots distant from the leafy gall. The short answer is no — at least not if you want clean cuttings. Since the bacteria can reside on the plant’s surface without causing symptoms, you can unknowingly be taking cuttings that harbor the pathogen, thereby perpetuating the problem.

    From-
    https://www.greenhousegrower.com/production/crop-inputs/how-to-prevent-leafy-gall-before-you-lose-plants/
    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
  • FairygirlFairygirl west central ScotlandPosts: 49,086
    I thought that might be the case @Pete.8. :/
    Not something I've got experience of, as I don't grow Dahlias regularly, and have only started growing them again recently. 
    Not very encouraging for you @macfall :|
    It's a place where beautiful isn't enough of a word....


  • mac12mac12 Posts: 150
    I've lifted about 35 and that's the only one showing any signs of anything so hopefully I'll be lucky 
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