Possible disease affecting rowan tree – identification needed

Hi everyone, gardening novice here. Over the past few weeks a lot of plants in my garden seem to have succumbed to various problems, just as I was getting in the swing of things! The worst affected is a small rowan tree, but I am struggling to determine what is getting the better of it. For the past few weeks the leaves have begun to curl, turn brown, and drop off; many of the berries have shrivelled too, and many of the leaves have developed holes. See the photo attached.

At first I thought it was a watering problem. To be honest I hadn't been watering the tree much compared with the shrubs, pots etc in our small garden, as I thought it was established enough to survive the hot weather. But for the past week or so I have been watering it lots, and this doesn't seem to have made much difference. Also, it is only a portion (currently about 1/3rd, but increasing) that seems to be affected – and surely if it was lack of watering, all the leaves would be drooping?

The tree was planted about a year and a half ago on the sheltered site of a former silver birch (which was far too big for the garden and had to be chopped down). There is an old rose nearby which always seems to have black spot, and recently next to the tree I transplanted (wrong time of year, I know) a largish fatsia japonica. A few of the leaves on the fatsia have developed brown patches, which I don't know the cause of (as I have been watering it religiously and checking for slugs/snails), but otherwise it looks healthy.

Problems affecting other plants in the garden appear to be mostly insect-based. Not sure what they're called, but little white things that curl leaves and make web-like nests in the crevices (esp of bay tree) and tiny little green caterpillars. I'm trying to be as organic as possible so I've been cutting away affected areas rather than spraying pesticide (although I do have a gun if necessary…).

Unlike these other shrubs, however, the rowan does not appear to be harbouring any insects. The trunk/branches appear to be fine, there isn't any sign of fungus either.

What does anyone think? Is it just a lack of water in this hot weather – or something more serious?

 

Rowan or Sorbus sp are the same family as Roses.
They are very susceptible to Fireblight.

https://www.google.co.uk/search?q=s...ved=0ahUKEwj2zNDtvo7OAhWnDMAKHc8AChsQ_AUIBigB

In our old garden we lost several special named Sorbus to it.
Had to burn the trees. Very sad.

Cannot say for sure that that is your problem...but it might be.

https://www.rhs.org.uk/advice/profile?pid=160

http://www.bbc.co.uk/gardening/advice/pests_and_diseases/identifier.shtml?fireblight

 

Oh dear, I hope it's not this. But I'm pruning those affected bits off ASAP just in case!!

 

Our trees started dying...then developed open weeping wounds on the trunk.
If it is Fireblight and you grub up your tree ....please avoid planting anything from Rosaceae in the same spot.

http://image2.gardenersworld.com/im...-4513-898d-5f04eebb8501&width=1024&quality=80

http://www.gardeningknowhow.com/plant-problems/disease/fire-blight-remedies-and-symptoms.htm

 

Looks more like scorch to me, also, the larger holes in the leaves look to have been caused by leafcutter bees.

 

Thanks – yes I think it could equally well be this. We do have a lot of leaf cutter bees about as I've seen their holes in lots of other shrubs. I suppose I'm just worried about the possibility of fireblight given its fatal prognosis, but then again the dead parts don't seem to be spreading in the way that descriptions of that disease would suggest. In particular it appears that only the leaves and berries are effected, not the woodier stems – though I need to investigate this more thoroughly (once I'm home and it's not raining).

It's really difficult to pinpoint these things when it could be more than one cause!

 

Have you looked at this Jon?
https://www.rhs.org.uk/Advice/profile?PID=160