Bob:

FB is worse on a rapidly growing tree not a stressed tree. I'd get rid of it if you are sure it's FB. I won't get another Kieffer. No reason to think another would do any better. I'd be looking for another more resistant variety.

That nurseries continue to grow and sell Keiffer and other seriously inferior pear trees to well-intentioned, but naive customers...... is hard to accept.Like selling spoiled eggs that you know are spoiled....to unaware egg buyers. 'Crooked' comes in all flavors.

Bobbo,

Are you sure you weren't sold a mislabeled tree?

Kieffer is supposed to be very resistant to FB. My understanding is that used to be widely planted in the South because of it's excellent blight resistance.

While "Kieffer" can get FB, it's hard to imagine finding a pear that is more resistant to it. "Ledbetter" perhaps.

It's interesting to learn that Keiffer is one of the more resistant varieties to FB, especially since I suspect that the Kieffer graft on a multi-graft tree that I bought last year is suffering from FB -- several inches of the tip, including flowers and leaves, has shriveled and blackened. The Bartlett and Moonglow grafts on the same tree show no signs of infection, nor do my single graft Bartlett or Moonglow trees. I've had no incidence of FB in previous years, so, without doing any investigating/research, I was inclined to believe that Kieffer is, in fact, more susceptible. I'm glad this thread caught my eye...

Just as some kids in a 5 child family can be more or less disease resistant than the other kids in the family, I suppose that "variability varies" in plants as well. Some Keiffers have been the tougher family members and some the weaker. Multitudes of plastic tags on Keiffer trees at retail outlets declare the frequently false statement of comfort that the tree is fireblight resistant. As a former president stated to those who learned of his bad behavior, "Are you going to believe me, or your lying eyes?" I bet that a photo of a Keiffer branch with both FB on it and the original plastic tag boasting of it's FB resistance...would be instructional.Since there are many Keiffer trees that have not proven to be FB resistant, the tags are untrue. Seedling fruit trees can have fruit with differing fruit qualities, and I suppose that 'seedling' fireblight bacterium can be different from their kinfolk also. Some may be 'Leroy Brown' bad....and possibly coming to a pear tree near you.

On a correctly labeled "Kieffer" plant it should just be the rare process of bud mutation that would alter FB innate resistance. I suppose different rootstocks conceivably can affect the FB incidence by promoting more of the more-susceptible growth flushes but have never seen this mentioned.

Fireblight resistant does not mean it's totally immune to fireblight.
While, in my experience, Keiffer is one of the most fireblight-resistant pear varieties, it's certainly not immune.
But, I tend to classify it as 'fireblight tolerant' - I can't begin to count the number of big, old Keiffer pears I've seen scattered across the countryside, most growing at old home/farmsteads, with numerous blackened shepherd's crooks throughout the canopy - but they 'take a licking and keep on ticking' - continuing to produce heavy crops of those good ol' firm, gritty, tasty fruits.
Can FB kill a young Keiffer? Probably. But once they get some size on 'em, they just seem to shrug off the loss of a few branches and roll on along.
There may be better pears, but it's DEPENDABLE.

I've had a similiar experience with a 2 year old Moonglow and a 2 year old Harrow Delight that bloomed for the first time this spring. I was excited at the prospect of getting pears from my 2 year old trees and then fireblight hit every flower on both trees. I've slowly been hacking away both trees trying to stay ahead of the fireblight traveling down the tree.

I planted these two varieties thinking fireblight wouldn't be an issue, now I'm wondering if they will be worth the trouble. I didn't spray anything and think I will give them another year, but use streptomycin next spring.

Anyone have experience using streptomycin?

I'm no pear expert but thought I'd offer an anecdotal story about Keiffer. When I was young, I'd visit my granparent's farm in southern PA. Without getting too nostalgic, it was one of the greatest places on earth. One of the things that I remember about the farm were the four tall pear trees that always seemed to have a crop of beautiful, delicious fruit (and I wasn't really a pear fan). My uncle now has the farm and those pear trees are still tall and strong, even if it is 40 years later (and to a child's eyes, they looked ancient 40 years ago, though I'm sure they weren't). I asked my uncle what variety they were and he said they were Keiffer and that they still produced nice, large, clean pears. Oh, and for what it's worth, I never noticed fireblight on those pear trees ever.

Growing up in the Deep South, Keiffer - and a few other Euro X sand pear selections were the mainstay - most of the pure Europeans, like Bartlett, didn't stand a chance of long-term surivival. Agreed, they're not one of those soft, 'butter/dessert'-type pears and some denigrate them as not being fit for human consumption, but having grown up eating Keiffer, Pineapple, and Orient, they are, to my palate, what a pear is 'supposed to taste like' - crisp, flavorful, and yes, somewhat gritty - not some soft, mushy, cloying thing.

Thanks for the responses....

So far, the FB hasn't returned, but I'm keeping a close watch. If it does, I'll take the recommendations of many and try another tree...maybe another Kieffer, but definately from a different nursery and supplier.

Bob

Keiffer on callery rootstock seems fb proof here, and texas a&m recommends callery rootstock. I'm not sure what the effect of the semi dwarf rootstock wod be, but some rootstocks aren't recommended in Texas due to fb problems