Joe:

I am pretty sure the answer is no, but I base this on the fact that I have never seen decorative cherries suggested as pollinators for fruiting trees, not because I have ever read it in black and white.

Pollination is an issue only for sweet cherries; all tart cherries that I know of are capable of self-pollination. Which type do you have? Among the sweets, some of the newer varieties (i.e. Lapins) are also said to be self-pollinating, although I am pretty sure that even those set more fruit with a companion pollinator. So if it's a sweet, what variety do you have?

Guessing that you are in an eastern location from your zipcode, I wonder how successful you have been if you have been growing sweet cherries. For most of us, they are pretty tough to grow because of cracking, rots, and disease issues.

Don Yellman, Great Falls, VA

Thanks Don. I had success when the trees were small and easy to spray. Most of the time I shared the cherries with the birds.
The issue now is getting the right chemical spray. Bonide Fruit Spray doesn't do the job. I can no longer buy what the commercial guys use. This year I will try the Bonide for two sprays and follow up with Lime Sulfur.

Joe:

It's good to hear from you, but you still haven't told us what kind of cherries you are growing, or where you live. With a little investigating, I have concluded your zipcode indicates Long Island, NY, but why do I have to investigate?
Location is a critical fact.

Still guessing, if you have sweet cherries, I am not surprised you have trouble with birds. The only answer for that type of problem is netting, but it is not an easy or 100% solution.

Why do you have a problem getting the right chemical spray?
What are the problems of your trees; bacterial disease on the trees themselves, or rot/cracking on the fruit? Bacterial disease can be controlled or at least delayed by dormant spraying with a strong copper solution. If something is eating the leaves, there are many insecticides that would be effective. If it is cherry fruit fly on the fruit, then cultural practices like hoeing around the base of the trees in winter can be very effective.

I certainly agree that Bonide Fruit Tree Spray is ineffective, but it is ineffective on any fruit tree because of its low concentration of active ingredients. What is the spray used by the commercial guys that you can no longer obtain? Does this mean that there are commercial growers of sweet cherries in your immediate area? If your problems are fruit cracking and/or rot, you may be trying to grow varieties that are inappropriate to your location.

If you can provide a little more information in critical areas of your problem, someone might actually be able to help you. But the questions should be longer than the answers, and rich in detail. Well thought out questions make the answers so much easier.

Don Yellman, Great Falls, VA

I live in NYC and have a Long Island Home. I grow 30 Apple trees, 6 pears and one Cherry. I had peaches but they were too difficult and removed them when they got leggy. Last year I lost the polinating partner, cherry, in a storm. I consider this a hobby and enjoy caring for the trees. I have always had trouble with desease and pests since I am mainly at LI on weekends. I spray regularly but I can not always apray after rain fall. I have used Rubigan, Topsin M, Captan etc.
I also use malathion and sevin. I had the greatest success when I used the Rubigan. Last year I used only Bonide. Sorry to say, the Bonide provided the least success and I am searching for something new. I have already used Bonide once at green tip. The Long Island EPA now has very strict rules and I can no longer purchase the chemicals that work. I used to be alone but now I am surrounded by neighbors. I have a notification issue and get complaints when I inform them that I will spray. I have an old Mantis, 15 gal sprayer which works fine. The tress are dwarf, mature and beautiful. My greatest success was about 80% clean but has diminished over the years. Last year my apples were edible but not clean: pies and apple sauce.
I just learned about Surround and wonder if the cost is worth the try. I apoligize for the tardiness of this answer and appreciate and value your thoughts.

Anyone know if you can use your rootstock as a pollinator for your scion? My rootstock keeps trying to put out branches on its couple inches above the soil line. My scion always flowers a ton, and usually while insects are buzzing around, but rarely sets fruit. I figure it could use another pollinator, so I'm considering letting some of those rootstock branches grow out enough to give a few flowers.

Looking at a pollination compatibility chart for fruiting cherries, it seems any cherry variety can pollinate a different cherry variety. There are several exceptions, some cherry varieties are apparently too genetically identical to eachother to be able to cross pollinate. Royal Ann, Bing, and Lambert are so are not compatible with eachother. Stella and Lapins are each capable of pollinating themselves, but have better yields when pollinated by a different variety.

I have tried to do some research into this, and it seems the issue with pollination is that most species of cherries require poll-en that is not too genetically identical, a natural defense against inbreeding. (it has to do with RNA sequencing, if both strings of RNA from each par-ent match up, it will set off a trigger that will prevent development)

Fruiting cherries and ornamental cherries are closely related. In fact, they have even made a cross between a cherry and a plum! I see no reason why it would be impossible for a cherry blossom tree to pollinate a fruiting cherry tree.

There is one issue, however. There are a few over-bred varieties of cherry that are unable to act as a pollinator, though they can be pollinated by another cherry tree. Unfortunately, both Yoshino and Kwanzan cherry blossom trees, the two most common of the ornamental cherries, are virtually sterile. It may be very difficult to get these to pollinate.

This post was edited by Socal2warm on Fri, Jan 9, 15 at 10:50

One site claims:
"Sweet and Acid cherries are also different species but can cross-pollinate each other - but usually cannot be pollinated by ornamental flowering cherries."

But this might only be because the two most common ornamental cherry varieties, Yoshino and Kanzan, are both virtually sterile, being hybrids (they have to be propagated by grafting). I wonder if it might work with one of the more "wild" Japanese cherry blossom varieties.

Fruits are seen on Yoshino cherry, therefore it is not sterile. 'Kanzan' is quite double-flowered, that would be a barrier to pollination right there - it probably has few, if any functional anthers.

I do not know whether Yoshino can be propagated by its seeds. The seeds might either be sterile, or produce offspring with traits very different from the parent cultivar, which would explain why the Yoshino always seems to be propagated by grafting.

I have also seen a documentary where it was stated that, unlike other natural cherry blossom varieties, the Yoshino does not attract bees or birds. The blossoms have no nectar to feed bees.

'Kanzan' is quite double-flowered, that would be a barrier to pollination right there

I'm not sure I get that? Many peaches and nectarines are doubled flowered. They all produce fruit quite well. And peaches are the same genus (Prunus) as cherries.

He refers to the fact that, being hybrids, most double-flowered ornamental cherries are sterile. I believe he is right, that the Kanzan variety is sterile, several sources on the internet claim this.

I am not sure about the Yoshino, there is a lack of information, and seemingly contradictory information. This type of cherry blossom tree might just not be very fertile.

This post was edited by Socal2warm on Sun, Jan 11, 15 at 18:33

Do you mean sterile in terms of not producing fruit, or not being able to pollinate other varieties?

^^^ It could be either....or both :-) Flowering or ornamental cherries are not heavy fruit producers at the best of times. Many are ancient natural hybrids anyway so some cross pollination did occur in the distant past but if any do produce fruit - like Yoshino does on occasion - it is because they are self fertile. And no, they are of NO benefit to the pollination of fruiting cherries either tart or sweet. They are incompatible.