Pruning out fire blight this time of year can be tricky depending how much fire 
blight you are pruning out.  Excessive pruning will encourage more shoot growth 
= more shoot growth means susceptible shoots to fire blight right now 
especially with conditions favorable for disease.  Trees should be hardened off 
right now meaning new shoot growth should be finished.  When this occurs, the 
bacteria stops moving in the trees and new fire blight incidence should stop.  
I would highly recommend avoiding doing anything that would encourage new shoot 
growth right now.  If it were me, I would just wait until the dormant period to 
aggressively remove everything.  There is much debate about cleaning pruning 
shears between cuts.  I don’t recommend it because the bacteria can move 3 feet 
beyond the site of visible infection, so disinfesting is a moot point.  Here is 
my latest article (June 26, 2018) in Penn State Fruit Times about what to do 
about fire blight now (it’s just below the info about apple scab):

And a note: do not spray any streptomycin.  Streptomycin is for bloom time 
only, and after a trauma event, such as hail. Do not spray it beyond these 
times.  If you are concerned about new shoot growth (if this is a new orchard 
pushing right now), I would recommend Cueva to limit spread of shoot blight.

Kari Peter, Ph.D.
Assistant Research Professor - Tree Fruit Pathology
Department of Plant Pathology and Environmental Microbiology
Penn State Fruit Research and Extension Center
290 University Dr., P.O. Box 330
Biglerville, PA 17307-0330

Office: 717-677-6116 Ext. 223
Fax: 717-677-4112

[] On Behalf Of Hugh Thomas
Sent: Thursday, July 19, 2018 1:14 AM
To: Apple-crop discussion list
Subject: Re: [apple-crop-2] What to do when fireblight hits tall spindle

Doug, it's sort of complicated. First, you probably know the bacteria travels 
from the tip downwards. The idea is to cut well below where the infection has 
traveled. You can cut away some bark and see where the brown area meets green 
cambium. I cut pass this point - well past it. I'm guessing I would cut about 
three times the length of the affected area. For example, if the tip has died 
back 6 inches, I would remove 18 inches of that limb. This is my gut but but 
this has worked for me in the past. I don't know the extent of your knowledge, 
but you need to be careful not to spread the bacteria with your tools and 
hands. Some people dip their tools in alcohol or Clorox between cuts. I use 
Clorox wipes on my shears, making sure I use a fresh wipe almost every cut, as 
the wipe ought to be very wet. On small limbs, say a quarter of an inch or 
less, I rip the limb off. The big thing is, take action now!!  With warm 
weather you can get a lot of damage. If you burn the limbs, don't let the smoke 
drift into your orchard - something a guy told me....

Sent from my iPhone

On Jul 18, 2018, at 10:24 PM, 
<<>> wrote:
Doug- where are you located?
What rootstock(s)?
What cultivars?
How old are the trees in your tall spindle?
What was your fireblight control program at bloom?
any post bloom program(s)


On Jul 18, 2018, at 9:26 PM, Doug Nelson 

I appear to have fireblight popping up in my orchard. The ipm group tells me to 
prune all limbs back to central leader and not to do any spraying.

What do you do?
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