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Thuja trees

Cat 3Cat 3 Posts: 107




Hi all can someone help me with my Thuja trees?  As you can see from the photos they don't look good.  I am not sure if this is normal or if they have a bug - and if so how to get rid.  I had 50 similar trees a year a go and they were all replaced, I don't want the current ones to go the same way.  

Please someone one help me, what is wrong and how can I make them better.  Should I remove the yellowing leaves and spray.  Trouble is once I spray it rains!!

thank you ????


  • nutcutletnutcutlet PeterboroughPosts: 26,854

    spray against what?

  • Cat 3Cat 3 Posts: 107

    Hi Nutcutlet, not sure if it's an aphid, Cyprus aphid - whatever is harming the tree.

    I don't want the trees to die and be bare sticks!

  • ObelixxObelixx Vendée, Western FrancePosts: 28,555

    If the last lot died it's a bit of "hope triumphing over experience" to re-plant the same tree because either your soil is impoverished/unsuitable/infected and isn't good for those trees.

    If you prune back to brown wood you'll just get brow wood as they only regenerate form the green bits.  No point spraying against an unknown problem but you could improve their situation and try to make them healthy with good nutrition.

    I think maybe you need to give the soil underneath a really good soaking and then scatter on some bonemeal to help grow healthy roots and fork it gently around the roots.  Top with a few inches of mulch from well-rotted compost or manure to improve the soil structure.  Do this now and it will work any magic over winter.   Hope for healthy new growth next spring.

    "We don't stop playing because we grow old; we grow old because we stop playing." - George Bernard Shaw
  • DovefromaboveDovefromabove Central Norfolk UKPosts: 82,185

    If you can't see any aphids there's no point in spraying against them ... and you'll be harming all the other wildlife that would predate on any aphids that might appear.

    Why were the other cyprus trees removed?  Have these been planted in the same place?  

    “I am not lost, for I know where I am. But however, where I am may be lost.” Winnie the Pooh

  • Cat 3Cat 3 Posts: 107

    Hi Doveftomabove

    the other trees with the exception of 10 Thuja and 10 leylandies turned brown, they were bare roots.  They were poor specimens and had suffered transport trauma.  The next lot were better specimens bigger and healthier, pots.  Have survived a year - no problems .  They were planted in the same area as perimeter hedging.

    the trees were doing okay until about 3 weeks ago.  It it normal what's happening or are they ill or have a bug sapping the life out of them?

    had I known how difficult they were to hrow I would have gone for only leylandi!

  • DovefromaboveDovefromabove Central Norfolk UKPosts: 82,185

    How was the soil prepared for them, and how have they been cared for since planting?

    I think the problem is more likely to be cultural (soil, conditions, care etc) rather than any beasties doing them in.    That being said, the loss of a few small sprigs is usually nothing to worry about.  What proportion of the trees has gone brown? 

    Can we have a photo of the whole row of trees, including the base please. 

    “I am not lost, for I know where I am. But however, where I am may be lost.” Winnie the Pooh

  • Cat 3Cat 3 Posts: 107

    Hi, I will get a photo for you.  The soil is clay but the landscapers made their own mix when they dug them in.  I have since added manur, bonemeal and fertilizer and I have added Ericacious soil as I read they like acidic soil.

  • Cat 3Cat 3 Posts: 107


    All, please see photos of soil and of the trees.  I have. I have noticed however a white minisule almost confetti like partical flying from tree to tree.

    Any thoughts on what that could be and if that is sapping the trees?

    Thanks for your help all. 

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