Hi I have a mixed apple and pear orchard and am wondering if they can spread fireblight between each other. Someone told me that there are different strains of fireblight for apple and pear. They said that it can ony spread from pear to pear and apple to apple. Is there any truth to this? Or is fireblight just fireblight.
Not sure of the details on that…
But from 2002 to 2015 or so… i tried to establish 2 pear and 2 apples in my small orchard…
I had 6 different varieties of pear… and 4 of apple… that died of FB thru those years. 2 apple starts thru all of that survived (early mcintosh)… and well one crab apple survived too.
Usually in year 2 or 3 when they started blooming good… it showed up in pears first… then apples.
I had a bradford pear near by too… and wonder if that was not a contributor to the FB.
They are pome fruits so yes fireblight spreads between them and others in that family. Here is additional information for those not familiar with the disease to help diagnose it
If you need to change varities its no big deal switch to a fireblight resistant type of fruit Top working Pears weather permitting
I have a few new apple trees going now. (1 to 3 yr olds)… disease reaistent varieties.
My 3yr old gold rush got 4 or 5 hits of FB this past spring.
One thing i noticed was that early in its bloom period… no problems… but later on in the last half of its bloom period… it was both warmer and wetter… and those late blossoms are where the FB showed up.
Next spring… i am going to let my young apples bloom early and may hand pollinate several… and then pull all the later blossoms.
While I can’t attest to this with absolute certainty, I suspect that the person who told you that there were different strains of the fireblight bacterium (Erwinia amylovora) which attack pears or apples was confused and was thinking of the different strains of Gymnosporangium fungi which attack apples, quince, pears, hawthorns, serviceberries.
I’m unaware of any different ‘strains’ of fireblight bacteria - but would not be especially surprised if there were.