The wild trees are probably one of the following: Black Cherry (Prunus serotina) Pin Cherry (Prunus pensylvanica) Chokecherry (Prunus virginiana) naturalized cultivated cherry such as Mazzard (Prunus avium) All of these probably have pollen that is compatible with cultivated varieties, and that is a fairly close distance, but it's unlikely that all the factors such as flowering season, time of pollen release and/or receptivity, and insect preference, would line up perfectly to make that happen. Then again, I'm no expert, and this is just a guess. If your hoping to rely on this for infertile varieties, you'd be out of luck I think, but then again, if you're worried about this crossing somehow affecting your cultivated cherries, you can probably relax.

Well, here is one. The cherries develop in tight clusters and inside those clusters rot develops. It is hard to get the spray inside those clusters. Because of that Lapins is no longer planted commercially to any extent, at least to my knowledge. The Lapins is a good pollenizer if it blooms at the same time as your other variety, but Lapins is known as a somewhat early blooming variety. It can be more susceptible to frost than the late blooming varieties that are self fertile: Sonata, Sandra Rose or Benton. Overall, IMHO these are better varieties along with the Sweetheart, Skeena, Attika and Regina. But those cherries may have other problems that will show in your location. Lapins is one of the best tasting cherries and if you have found it works well for you in your area, then you are really ahead of the game.

The flowers do smell awesome! (sweet cherry)... Kristin needs to be made self fertile! The tree is a monster when it comes to surviving cold temps. I may just make a yearly trek to Door County and get my sweet cherry fix! Although last year 100% of the crop was destroyed. This year could be a bumper crop...

Generally 2 trees only need to be within 50 feet (15 meters) of each other to cross pollinate. Pollination does usually require insects (most commonly bees), but can also be done by hand. Even if you do not commonly see bees in your yard, it is usually nothing to worry about. The bees will appear when the tree is covered in blossoms. In many parts of the country people only need to plant one apple tree in their yard, because there are usually a few other apple trees (or crabapples) growing somewhere in the neighborhood and the local bees are likely to be carrying pollen. The only reason I could see to ever want to plant the trees closer together is if they are very young trees with only a handful of blossoms that are unlikely to attract many bees. But in that case why not just pollinate by hand? The quality of the fruit is entirely dependent on the tree it is growing on; the variety that was used to pollinize it does not affect the fruit, though it does take a pollinizer for fruit to be able to form in the first place. Sweet cherries have a different number of chromosomes from sour cherries, and a cross between the two results in a triploid hybrid. Such a hybrid can still produce fruit, but the seeds are sterile. Sweet cherries have 16 chromosomes, while sour cherries have 32. Somewhat interestingly, wild Japanese cherry blossom trees have the same number of chromosomes as sweet cherries, while wild cherry varieties native to America (these include Black Cherry and Capulin) have the same number as sour cherries. This has implications for cross-breeding potential. Many cultivated cherry blossom varieties, including most in the serrulata group, are sterile triploid hybrids (with 24 chromosomes), and can only be propagated from cuttings.