lemon tree forks into two trunks just above the soil and for many
years has grown normally and fruited well. Now the right-hand side
of the tree has little foliage left while the other is growing normally.
I can see no signs of borer. I apply fertiliser and copper and oil
sprays regularly. Can you advise me?
your photos I suspect borer may be the problem, even though you
haven't seen any evidence. A borer close to the base of that side
of the tree could cause these symptoms, so check carefully - you
might find a small entry hole. If you do, try inserting a piece
of fine wire into the hole in the hope that you might spear the
borer. However, they can be very hard to get at and, as the damage
is already done, it may be too late to save that side of the tree.
Damage to the roots on
that side of the tree, caused by poor drainage or physical insult,
may produce similar symptoms.
I recommend you remove
all fruit from that side of the tree to reduce stress - given good
conditions it may recover. However, if that side of the tree continues
to deteriorate you may have to resort to removing it.
Gardener, Issue 206, 2006, Page 37
Reproduced with permission from the former Weekend Gardener magazine. The views expressed here are not necessarily those of the RNZIH.