Sickly Sorbus

Really appreciate some advice/guidance on a sickly sorbus (Chinese Lace) planted about three years ago.

Towards the end of last year's growing season, I noticed that the leaves turned red quite early and seemed a bit crispy although they stayed on the tree well into winter. This summer however, leaves have turned crispy before mid-summer and the berries forming are shrivelled.

Worryingly, there are several serious cracks in the bark on the main trunk from ground level up to a height of about one foot above. The trunk feels slightly soft in these areas. I've attached a couple of photos (I hope!). My gut feeling is that it doesn't look at all well.

Maybe irrelevent, but in spring 2011 I cut down a Cordyline infected with Slime Flux about ten metres away from the Sorbus. The Sorbus has been pruned only once (at time of purchase, about three years ago).

Thanks in anticipation.

 

Hi AJ34

Looks like some sort of canker/butt/root rot. How the tree deals with it depends on how healthy it was to begin with and what the causal agent is. With these basal decays it is difficult to determine how much of a life left the tree has, and if the tree now poses a threat to anything nearby. Monitor and address any new issues accordingly.

 

Thanks for your reply, HarmonyArb. It's getting worse by the week so I just might try some drastic surgery - kill or cure - remove the dead wood and rub with dilute bleach and alcohol!

 

I think harmonyarb is correct, from the pic it does seem to be a canker. It appears to have entered at the graft area of the tree which is common as in essence it is an unnatural union and can often be weak.
The bark around the lesions looks to be swollen and punctured which would lead me to believe that it is a bacterial canker - no cure unfortunatley if it is :(. When these cankers appear on a side branch they can be cut back to healthy wood and destroyed but when it is on the main trunk, the whole tree will eventually go as the bacteria clog up the whole plumbing system of the tree.
Just to add, there could be quite a strong possibility that it is Fireblight, considering the tree in question. Again, it is bacterial and there is no cure. Care should be taken as it can easily spread to other susceptible hosts in the area.

Hosts include:
Amelanchier (June Berry) Malus (Apple)
Chaenomeles (Quince) Mespilus (Medlar)
Cotoneaster Pyracantha (Firethorn)
Crataegus (Hawthorn/Whitethor Pyrus (Pear)
Cydonia (Quince) Sorbus (Mountain Ash, Whitebeam)
Eriobotrya (Loquat) Photinia davidiana (formerly Stranvaesia davidiana)