To the plant, pollination is pollination. To the gardener who wants particular results (such as wanting to keep an heirloom variety pure), cross-pollination (cross-breeding) is something to avoid. To a grower or scientist who is trying to create a new variety, cross-pollination is desirable. It's all on your point of view. Like Dave said, some varieties are very genetically stable, like his Nantes carrots. Others, like curcubits, are notorious for cross-pollinating. If you're growing certain kinds of decorative gourds, and zucchini or other squashes, insects will cross-pollinate them very easily, and if you saved the seeds from your wonderful zucchini and planted them, they could end up being something almost unrecognizable and tasteless. "Does cross pollination always create a hybrid?" Yes and no. Technically, every pollinated plant is producing a hybrid, because every plant from every seed has a tiny, microscopic difference from the plant next to it, although it is, for most purposes, the same. Only cuttings, cloned or tissue-cultured plants are exactly the same as the parent stock. Plants labeled 'hybrids' have been crossed from plants with noticeably different qualities. If you crossed two of these 'hybrids', they would most likely revert back to the qualities of one or the other of the 'parents'. Granny Smith apples came from crabapples. If you planted a Granny Smith seed and nutured it for several years, you would probably end up with some sort of crabapple or similar variation. Two additional bits of info (just to confuse you a little more ;-) ): 1) You can be growing two similar plants near each other, but if they flower at different times, they won't (can't) cross-pollinate. Corn is a good example: there are early, mid-season and late varieties of corn. Corn cross-pollinates easily because it's wind-borne, but if they tassle (the 'flower') at different times and there is no other corn around (esp upwind), they won't cross. If Alfie's apples (above) needed a pollinator variety, and he accidentally planted a variety that bloomed a month after his Macintosh, he wouldn't get any apples. 2) OP varieties can be 'manipulated' even within the variety. You can have a packet of seed of a single variety of an OP plant, and each seed inside will have a tiny difference about it. Many people will grow a particular variety that they like, and they will watch for 'special' ones among that variety: a tiny bit earlier, a slightly larger fruit, a sweeter flavor, a slightly higher yield, etc, and they will mark it and let a few fruits of that plant mature and collect the seed. The next year, they plant that seed, and again look for 'special' plants. Every year, they keep doing this, and end up (hopefully) with localized variety within a named variety that is especially suited to their local conditions. It's still the same variety, it's still OP, it's just an improved variation within that variety. If you bought seeds from a grower in BC, and you bought the same variety from a grower in ON, the local seeds might produce plants that had a slight edge on local conditions, concerning earliness, adaptibility to hot summers, or ability to grow with a bit less water. The seeds from BC might adapt better to cooler summers, more humidity, and a longer season.

Your biggest challenge is to have overlapping bloom times - if you don't have that then they can't help each other. There are several threads that discuss bloom times for various viburnums ("Viburnum dentatum & friends" is one), you might want to look at those. Here is another one specifically about V. dentatum and cultivars. The other issue you could have is compatibility. While I do believe that many of the native viburnums are compatible for cross pollination (V. dentatum and V. nudum are the two native ones you mention), it is possible that they are not compatible with your non-native ones (the other four that you mention) even if you do have overlapping bloom times. Hope that helps. Here is a link that might be useful: V. dentatum & friends

Ray, V. nudum 'Winterthur' is a beautiful shrub--glossy foliage that turns a lovely mahogany in fall, and those handsome berries. In my experience, it's much smaller than many viburnums; mine, in for 6 years, are still under 6 feet. They could be pruned up a little to look like little trees.

Bon, : ) You are so sweet. I grow a gazillion different kinds of flowers every year, but the ones that grow every year are the ones that reseed and come back on their own. I do try to renew them with fresh seeds purchased every few years (like, for example, with new Laura Bush seeds from Wildseed Farms). I want flowers that will self-sow and perpetuate themselves fairly well over time because I don't want to start over from scratch every year. Many perennials can be iffy in clay. They'll thrive for a few years and then an extra hot, dry year (like 2011) will kill them, or an extra cool, extra wet year (like 2007) will get them. Those two extreme types of weather have done a good job on their own of weeding out perennials that cannot tolerate my clay in both extremes. So, when I find something that thrives in both types of extremes, I grow lots of it...hence, the huge poppy population for example. I am fairly picky about flowers----they have to be able to thrive in amended clay with little to no irrigation, no fertilizer beyond what compost and other organic soil amendments provide, only minimal deadheading (because I stay so busy harvesting and canning), no pampering of any kind.....and they need to stay disease-free. That means that I don't bother even planting anything reputed to be picky, persnickety or needing pampering. It also means the flowers I grow bring me much joy because they aren't stressing me out by being high-maintenance. And, yes, many of my favorites either are wildflowers or herbs, and they won't die and you can't kill them,making them perfect for a gardener who has lots of fruits, herbs and veggies and not all that much free time to devote to flowers. Having said all that, I'll give a variety of flower three years to prove its worth if I really want to grow it. If I cannot get it to succeed here with minimal care after three tries, I'm done with it and move on. If I cannot get it to grow at our place after 3 years of trying, I say "it won't grow here" and give up on that one. No one loves the wildflowers more than I do because they are so danged tough. A lot of flowering herbs are the same way---just tough, tough, tough beyond belief. I've been having fun planting flowers that need really well-draining soil in the back garden's sandy area the last couple of years because I cannot grow those in the front garden. However, anything I plant back there may (or may not) be eaten by voles in July and August when they exhaust their supply of whatever the heck they eat down in the woodland before they migrate upland to our garden plot. Wildflowers are kinda perfect for this area because I can watch our pastures and see if those wildflowers survive all summer. If they do, then the voles likely aren't eating them. I love agastache but haven't been able to grow it in the clay soil out front. Last year, Agastache "Blue Fortune" performed wonderfully in the soil out back and, as far as I know, the voles didn't eat the plants unless they have eaten the roots this winter. 'll see if the plants come back this year. If they do, I might plant some other agastache varieties back there. I am in love with all the plants at High Country Gardens but most of them need very well-drained soil that I don't have. So, if I can find something like agastache that the pine voles don't bother, I can order some of the different varieties from HCG and grow them back there, which would make me enormously happy. My daffodils down by the front driveway gate are about to bloom. I am so excited that something is about to bloom because so far the cool-season wildflowers have been really skimpy this year, and I think it is because of all the recent cold weather. The prettiest wildflowers on our property this year are the dandelions. People who love a perfect green carpet-like lawn don't like dandelions, but I love their cheerful yellow flowers, especially when they are the only thing blooming.