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We have two birches in our garden, and they are losing lots of leaves.  The leaves have small brown blotches on them, and the stems are brown where they connect with the branch.  Any ideas would be welcomed!

think this can be caused by hot spells the tree gets stressed and drops its leaves :)am sure i read this somewhere,someone may have more info on it good luck. :)

They are shallow rooted if I remember rightly so more affected by drought.

We seemed to have lots of rain right through April and well into May, and are not in a "drought" area, so I'd be surprised if it was that, although the two trees are right near a leylandii hedge which will take up a lot of water I guess.  So maybe that's it!