I’m going to bring up a point that nobody wants to talk about. @39thparallel and I speak of it occasionally. Im going to tell you the truth about all rootstock that might change the way you see everything. Many refer to this thread Pear rootstocks revisited in 2022
How many have waged war against fireblight? If you haven’t you will. Will you win this war? The fundamental way we think needs to change. Consider nature does not have a fireblight problem and we are the problem. Wild callery trees are not dying. I have said it before but callery will someday be the next rootstock. The genetics are different on every wild callery. Our method of propagating clones is catching up with us. Consider nature adapts and callery pears have done that. Every callery pear in the field is different and fireblight simply cannot adapt that quickly to that many different genetics. The result is wild callery are winning. Orchards of ohxf rootstocks are dying. I had a ohxf333 killed to the ground several times.
I’m starting an ounce of seeds. Should equal 1200 or more rootstocks.
@clarkinks
Callery might survive the weak strain of fireblight you have in the midsouth. The aggressive strain we have in southern CA kills them in a matter of decades. In the meantime, they are a major source of the disease.
Reading the USDA and OSU Pear guides they rate Callery a 4 against fire blight. Fairly susceptible.
Our naturalized Pyrus Pyrafolia is fairly resistant. But they are quite different from domesticated Pyrafolia varieties. Not sure if it is a good root stock or not. It does not sucker like Callery though. A little bit. But not covering a football field in a few years…lol
Yes in California, the callery would be devastating. I believe in the midwesst callery are here to stay. They are more resistant against fireblight than any fruiting pear. I understand genetic diversity is the secret. Within 20 years a new ohxf sstrain could be made as well resistant to the new strains of fireblight. Crossing several highly resisstant types of pears would be even better. In my arra nature is doing it for us if we like that or not.
@clarkinks
Our fireblight strain has been showing up in Arkansas and Missouri. Your recommendation for Callery as a pear rootstock might be poor in the long run.
It is not really a recommendation it is more of an observation. Many of my original trees went in the ground on callery and have produced pears 30 years. I’m pointing out that diversity is the secret to their success. Im not an advocate for invasives rather the opposite but i am pointing out a mistake with clonal propagation is occuring.
A beaver recently ate my 35-foot ayers tree. The rules are different here. It was my first pear. Thankfully, i have many more. I anticipated that tree fruiting only a short time. That was not the case. In all the years i had it, there was never any disease on that tree. I am fortunate indeed im doing what i have been, and it is working for me on hundreds of pears. Wild callery is highly resistant to fireblight. You can brush them with a fireblight here, and they do not develop the illness. Gmo are a worse solution than callery. Ohxf87 & ohxf97 are more resistant than ohxf333 for now, at least. I have developed several of my own rootstocks and interstems i use for my own needs.
I’d agree that you are advocating it.
This will no longer be the case in several locations east of the Rockies, and eventually in your location as well.
I know that I will take some flak from you Callery lovers out there, but I will take this opportunity to remind everyone that Callery is a horribly invasive species. Sales of Callery have been banned in three states: Ohio, South Carolina, and Pennsylvania. OH and SC also ban planting and growing. Other states strongly discourage planting them.
These trees will spread from cultivated plantings and quickly dominate surrounding areas. According to Richard they are a major source of fireblight in California. They may be a free source of rootstock but they also sucker aggressively. And when your scionwood breaks off the Callery rootstock you will be responsible for the local invasion.
You may say that the battle against this scourge is already lost, but please do not harbor this defeatist attitude. Let’s all do our part to save our forests and open spaces. Here at our local YMCA we are enlisting young people to join in the fight and cut down these trees on the property, replacing them with other ornamental species. It’s a great lesson in stewardship.
The key thing i want to point out here is to kill callery trees for good might be desirable by many, but it will never happen. You can graft an abandoned field over to fruiting pears quickly. That stops the spread of seedling callery and yields fruit. Definitely dont buy callery. The orchard is already in place. Just use what God gave you. We need to stay ahead of fireblight which nature has been doing and we have not been doing.
Not to be a defeatist, but realistically, Pandora’s box has been opened and there’s no getting the genie back in the bottle (to mix up metaphors, lol). People are cutting down one Callery tree in their yard and feel like they’re helping. Meanwhile they drive by 10,000 Callery trees on the way to work. Barring an unrealistic bounty on them followed with proper herbicide application, no one is going to put a dent in their population. They’re naturalized at this point. I keep encouraging people to graft their Bradfords and Callery pears over to decent fireblight tolerant fruiting pears instead of just cutting it down, wasting a really nice drought tolerant root system, and planting a “native” tree.
This is purely anecdotal, but in the SW MO Ozarks the Callery trees are way more fireblight resistant than most unsprayed fruiting pears I’ve seen.
I agree with everything you observed as well. Many people talk of gmo rootstocks but that has not worked well with anything else. Gmo like hybridization is a temporary solution that causes more problems than it solves. Like you i’m not advocating for callery just observing how things are. To call callery highly resistant where you and i are is an understatement. Nurseries like Starks that are located in nearby Missouri like you are likely struggling to combat this fireblight.
Invasive species is an economic idea not an ecosystem idea. Ecosystems are strong and resilient. Individual species come and go. Feeling defeated should be expected if you’re fighting against evolution. Species that fill their fitness space perfectly are the ones that tend to go extinct though, so I wouldn’t put all of my eggs in the Callery basket any more than I would try to eradicate it. Like Clark mentioned, diversity is key. The species that are existing in the fringes, not thriving but surviving, are the ones that tend to survive when conditions change. Maybe Callery is taking advantage of changing conditions, or maybe it’s fitting the current fitness space to perfectly to make a lasting run in areas where its considered “invasive”. Time will tell.
Callery is not acceptable as a long term rootstock. It has too many problems which show up after a few years. Here are some of the things wrong with it:
- Susceptible to fireblight in many areas
- Limited genetic base, if you don’t believe this, go back and read the import docs
- Not available as a dwarf… and dwarf or semi-dwarf is badly needed in the industry
- Growth habit of varieties on callery is generally aggressive, not focused on fruiting