Pear Tree and Fireblight Disease

Q. I  attached pictures of my pear tree. Do you have any
idea why the leaves are doing this strange browning and dying out? Never seen
anything like this.

Both pictures were submitted by the reader. Sure looks like fireblight disease to me.

A. I’m going to state the obvious. The leaves turned
brown because they are dead or dying. I know you want to know why they are dead.

The usual reasons can be
wide-ranging and related to either diseases, damage to limbs or the trunk or
soil problems. The possibility that concerns me the most is a disease called ‘fireblight’.
Search the Internet or my blog for pictures of what fireblight disease looks
like. Check the entire tree for this kind of damage.

Advanced stage of fireblight disease. The tree can still be saved by pruning back about 12 inches to stop the disease from spreading.

If you are at all suspicious of
fireblight, then prune out these branches 6 to 8 inches below this area and use
a sanitized pruning shears. If more than one cut is needed, then sanitize your
pruning shears between each cut. Use 70% isopropyl alcohol or higher or a cigarette
lighter and heat up the blades to kill any possible disease organisms that you
could transfer to the cuts.

Make sure the tree was planted
with compost mixed into the soil as an amendment at planting time. Never
surround fruit trees with rocks or gravel on the surface of the soil. Woodchips
that can decompose and benefit the soil are much preferred over rocks for any
kind of fruit tree.

Fireblight disease on recently planted ‘Bartlett’ European pear.

If you are watering daily, the
tree roots could be suffocating because the soil stays wet and not draining
properly. Root suffocation can also cause the leaves to die and turn brown or
black. Stop daily watering. Water every other day or every third day during the
heat of the summer. Apply enough water when irrigating to cover a large enough
area under the tree to initially wet and keep this soil from totally drying out
until the next watering.

Pear trees grow very well in our
climate if the soil is prepared at the time of planting with compost and if the
soil surface is covered in woodchips after planting. You should never have to
water daily if you are giving the trees enough water, over a large enough area,
when you are watering.