We’ve already had a number of customers bring in examples of fire blight afflicting their pear trees, if you recognize this on your pear trees, read on for our recommend management and prevention including what control you’ll want to grab from the Garden Shop!
Note that fire blight is a common and frequently destructive bacterial disease of not only pear but apple, crabapple, pyracantha, quince and related plants.
As you can see from the photo above, fire blight can attack all parts of the pear tree causing shoots, leaves, fruit and flowers to blacken or brown and die. Dead leaves and fruit cling to branches throughout the season, giving the tree a scorched appearance. And we are seeing it more this year because of the weather - a warm spring with intermittent rain is just the recipe for fire blight to thrive under.
As of now, copper products are not effective as fruit has already begun to form. Right now to prevent the spread of fire blight, remove the infected wood as soon as you see it. Dip shears in 10% bleach (1 part bleach, 9 parts water) between cuts and remove at least 12-18” below the canker.
During fall and spring there are two different controls to use on your pears:
Copper Soap - An organic control, apply 2 oz. in fall or early winter once your trees go dormant. This will occur when all the leaves fall off your tree. In spring, apply .5 oz when blossoms begin to open and repeat sprays every 7-10 days until flowering has ended.
Liqui-Cop - For pears and quinces, apply 1 tsp per gallon when trees are blooming at 10% in spring and repeat every 5-7 days through flowering.
If you’re treating other trees besides pears, make sure to read the back of the bottle and see what specific instructions are listed. Concentrate and application may differ across plants.
Although you may be alarmed at the appearance of these small unsightly spots, this is not the beginnings of fire blight but leaf spot.
Easily identified by its round shape and definite edge with a darker border, leaf spot won’t cause long-term damage to your tree and is easily managed by removing the infected leaves. Just like with peach leaf curl it is important to bag up the infected leaves and dispose of them to keep the infection contained.
Questions? Stop in and let’s talk pear health, ornamental or edible!