Lacebark, Inc., P.O. Box 2383. Stillwater, OK 74076 Much has been written in recent years about the need to plant only "native" species. But the key questions are often overlooked. Is a plant best adapted to where it is "native"? Once urban soils have become homogenized and modified with all sorts of construction debris, is any plant "native" to that site? Are all introduced species "bad"? Shouldnt adaptation of a plant to a site or region be considered instead of just "native" vs. exotic? Just because a plant is "native" to an area, does that mean that the location/conditions are where is grows best? All these are questions that need to be considered. Our focus should be on plants adapted to a site and with acceptable "manners" relative to the desired purpose. The plant that grows best on a site may or may not be the most desirable and it may be a native or it may be an exotic. In many instances I feel requirement is often confused with tolerance. For example, my research that created the micronutrient fertilizer, Micromax, was done with tomato and pyracantha only. That was in 1978. Micromax has been the number 1 selling micronutrient fertilizer in the world for years. How can it be that research data from one vegetable and one woody shrub relates to thousands of species worldwide? I believe it is because all or nearly all plants have the same requirement for optimum micronutrient nutrition. To study this question I have grown an array of species of plants with a wide array of micronutrient levels. Azaleas were dark green and thrived in a narrow band of micronutrient levels. The same was true for African violet and blueberry. On the other hand, juniper, arborvitae, marigold, and crabgrass were green and attractive over a huge range of micronutrient levels, hundreds of times wider than for the azalea. BUT all of the test species grew best with the same level and combination. These data support the view that plants have vastly different degrees of tolerance, yet for optimum growth, about the same requirement. Now consider the initial questions raised: Is a plant best adapted to where it is native? If a plant grows faster, produces more flowers and seeds which germinate readily and establish new plants more rapidly in a new location vs. where it is native to which site is it best adapted? The new location of course! This is exactly the situation with the Melaluca leucadendron or punk tree in south Florida vs. its native habitat of Australia. In its native range in Australia, it is not an aggressive, invasive tree. A striking reverse situation exists with Pinus radiata, Monterey pine, native to the California coast where it grows at a moderate pace and is not especially vigorous. Yet in New Zealand and South Australia, Monterey pine grows vigorously and creates magnificent timber. A study of fossils reveals that many plants were "native" to locations far removed from were they are currently "native". Conditions change and with the change plant species shift or adapt. Just because a plant is "native" to a site does not necessarily mean that site and conditions are optimum for its growth. Once urban soils have become homogenized and modified with construction debris is any plant "native" to that site? No, other than crabgrass and then only because it has, perhaps, the widest tolerance of all species. On the other hand, many species have such a wide tolerance that they can grow reasonably well under such adversity. For example, southern wax myrtle, Myrica cerifera, is native over a wide range of conditions throughout the southeast USA. It is native to the almost pure sand soils of the Ocala National Forest in north central Florida, to stream banks where flooding frequently occurs, to alkaline soils along limestone outcroppings and acid soils along the swamps of southern Georgia. This is a species with a huge tolerance for growing conditions, and it does well in nearly all urban conditions. In order to have successful plantings on highly disturbed urban sites, we must look to plants with a wide range of tolerance. Along with wax myrtle, one of the most tolerant and adaptable shrub species that works well is Nandina domestica, native to China. Nandina would be at the very top of my list of broadleaf evergreen shrubs with many attractive qualities and good mannersÂnative or non-native. Nandina has attractive foliage, flowers, and fruits, is nearly disease- and insect-free, produces few invasive seedlings or rhizomes, is easy to maintain, and grows well in a huge range of conditions. Are all introduced species "bad"? Absolutely not. Nandina, lacebark elm, Chinese pistache, Pittosporum tobira, and on and on are introduced species that are well adapted to much of North America that have good manners and make good "citizens". On the other hand, melaluca, tree of heaven, Japanese honeysuckle, kudzu vine, and many other species are too well adapted: grow too vigorously and reproduce too freely so as to be undesirable in the view of current day society. The bottom line is that just because a plant is growing "native" under certain conditions, does not mean that it is at its peak or optimum. It simply means that it is able to tolerate the current conditions and survive. Further, relative to the evolution of the species and the changing local site conditions or site conditions of a much larger region, the species may be relatively "new" and will become more vigorous and aggressive in the future as conditions become more favorable or it may be on its way out because it has reached its limits of tolerance and will eventually become extinct. At this point in time no one knows. However, we get a "feel" for the answer from various experiences. Because of the positive plant response and adaptation to such an array of conditions, southern wax myrtle appears to be still expanding its "native" environment. On the other hand, black cherry, Prunus serrotina, appears to be less and less tolerant to environmental conditions and may become extinct in another century or two. In my view, it would be simplistic and foolish to plant only natives. Likewise, it would be foolish to plant only introduced species. Our focus should be on species adapted to the site and with acceptable manners regardless of where they happen to be "native at a particular time in the glob al picture. ------------ -------------------------------------------------------------------------------------------------------------------- Carl Whitcomb is author of ÂKnow It and Grow It: a guide to the identification and use of landscape plantsÂ, 820 pages, 8.5 by 11 format, hard cover, over 2000 black and white photos of most of the woody plants, native and exotic, that can be grown east of the Rocky Mtns. $60.00 + shipping. Also, ÂEstablishment and Maintenance of Landscape PlantsÂ, 630 pages, 6 by 9 format, hard cover and many photos. $35.00 + shipping. Phone 405-377-3539 or Fax 405-377-0131.

To take out the location-loaded terms 'native' and 'cultivated', I think what you're trying to ask is, "can hybrids occur between species from different continents"; the answer is yes, provided the species are closely related enough. There are plenty of examples. In Prunus, the hybrid between P. avium (Europe) and P. emarginata (N America) is known, recently named Prunus à pugetensis. I'd doubt that P. serotina could cross with P. avium though, as they are in different sections of the genus (sect. Padus, and sect. Cerasus, respectively). Resin

I've only found a few mail-order nurseries that specialize in seeds of native US wildflowers (violets or otherwise), and carry a large selection. Here are two well-known and respected ones, and the violets that they carry: Prairie Moon Nursery (PMN) (catalog is in PDF format only, probably should download from their website) http://www.prairiemoon.com/ PMN currently offers four species, V. palmata, V. papilionacea, V. pedata, and V. pedatifida, but seeds of only the last two. I would recommend V. pedatifida, the Prairie Violet, for your project, as it is a true native of Illinois, also it has interesting deeply dissected leaves similar to a bird's foot, one of a few species with this leaf form. (The other species offered as seeds by PMN, V. pedata, has a similar appearance, and a common name of Birdsfoot Violet. However, V. pedata has a strong preference for truly sandy soil; its ideal soil is described as coarse sand or even "pea gravel" mixed with organic material. V. petadifida should thus be easier to grow than V. pedata on most sites.) PMN also gives detailed germination instructions. New England Wildflower Society (NEWFS) http://newenglandwildflower.org/nursery.htm NEWFS won't be selling seeds again until January 2005; their catalog lists five violet species: V. brittoniana, V. labradorica, V. pedata, V. rostrata, and V. striata. Of these, the description of V. rostrata (Longspur Violet, named for the flower form) sounds especially promising for a groundcover: "Normally a violet colored violet, this form from member Bunny Traylor's garden is a pleasing rosy purple. Like Labrador Violet, this species begins as a heavily flowered clump, then creeps along during the growing season, becoming mat-like by fall then dying back to a central crown again. Self-sows readily." V. rostrata is an eastern species whose western limit is close to the Chicago area, according to the USDA database, so I think it "counts" as a true native for you. V. pedatifida and V. rostrata are both "upland" species that do well in relatively dry (but not desert-like) soils. V. striata (Striped Cream Violet), definitely a true native (Chicago area), is taller (to 12 inches) and bushier than the others, and prefers more moisture - it usually grows in wet areas, unlike the other two. I think it would be worth trying all three; the color combination (typical violet, rose purple, and white with violet stripes) will be attention-getting if it works.

If you want a good flowering dogwood that's about the same shape and size as the Florida version, get a Cornus alternifolia. It's native to here (you in London, me in Woodstock) and we have one growing naturally and nicely in deep shade in our woods. Even with the deep shade it gets lots of pannicles of flowers so in as much sun as you have, it would likely produce a grand amount of flowers. It 'is' technically an understory shrub so you may wish to position for a bit less length of sun than your current one but I can highly recommend this native shrub from experience and it is now showing up regularly in regular garden nurseries as part of their stock. I would suggest calling ahead to see if specific nurseries have it so you don't waste gasoline but in London I don't think you'll have any trouble finding one. I'm pretty sure the Nursery up in Hyde Park will have one but I don't know the name of the Nursery...??? Hyde Park Nursery??? lol. Barb/knottyceltic southern Ontario, CANADA