What is a "native" tree species?

• A hard question! One answer is that native tree species grow naturally in the wild in a particular region.
• Usually, the contrast is made between a native and an exotic (or introduced) species.
• But certain trees and shrubs introduced since 1600 (e.g., common buckthorn) are now widespread.
• Also, a native in one region of the Northeast may easily not be native in another, much less in the entire country.

• In recent years, there has been heated debate about native vs. exotic species.
• Some people want to avoid an invasion of exotic species into the natural landscape.
• Others argue that native species resist pests better, and thus are easier to maintain.
• Some believe that natives are better adapted, so are less stressed by climate extremes.
• And a few people just seem to want no "foreigners" around, period!

• There is no single or simple answer to this question.
• Some exotics (like Norway maple or Tree-of-Heaven) really can be invasive.
• But some natives (like aspen, black locust, or black cherry) are also invasive.
• And invasiveness depends on a favorable and available site.
• Regional natives grown from regional seed usually resist regional pests well.
• Climate tolerance depends more on provenance or chance, not "native" status.

                                                    Serviceberry in a lawn setting

• Tree species native to a given region may not do well in disturbed urban sites.
• Here are some species native in much of the Northeast and often good for street tree use:
• red oak (Quercus rubra)
• sugar maple (Acer saccharum)
• hackberry (Celtis occidentalis)
• white ash (Fraxinus americana)
• scarlet oak (Quercus coccinea)
• hophornbeam (Ostrya virginiana)

• These are often good for landscape use in the Northeast:
• serviceberry (Amelanchier spp.)
• black gum (Nyssa sylvatica)
• hornbeam (Carpinus caroliniana)
• swamp white oak (Quercus bicolor)
• tulip tree (Liriodendron tulipifera)
• river birch (Betula nigra)

• Try these for poorly drained or intermittently flooded soils in the NE:
• bur oak (Quercus macrocarpa)
• tamarack (Larix laricina)
• red maple (Acer rubrum)
• green ash (Fraxinus pennsylvanica)

• Remember, though, your site must meet the cultural demands of the species.

• Always try a local nursery first. Their stock is usually more regionally adapted.
• Regional wholesale nurseries often carry native species--but try to check the seed source!
• red maples grown from southern seed sources, for instance, will do less well in the north than seed from northern sources.
• For less common natives, you may have to order from catalogues of specialty nurseries.