Sour Gum

Sour Gum, Black Gum, Tupelo
Nyssa sylvatica
As soon as I think I have run out of trees to write about, another one pops into my head.  Black Gum, Sour Gum, Tupelo (Nyssa sylvatica), or whatever other name it goes by, is one of those trees. It is the sort of tree that makes me wonder why Red Sunset Maples ends up on every other tree list, instead of a more interesting tree such as this one.  In fact, Nyssa sylvatica was selected the 2008 Urban Tree of the Year by the Society of Municipal Arborists.  It is a medium size tree for urban sites, no more than 45 ft. in height and 25 ft. wide, and moderate growth with tough but flexible limbs.  The real payoff is the spectacular early and long lasting fall color.Although sometimes challenging to transplant, it is well worth the effort.  Root pruned, container, and grow bag grown trees will probably establish most easily.  It is a species that tolerates both wet and dry sites, and prefers acidic soils.

Of particular interest to growers and buyers is that forms can vary significantly when grown from seedlings.  Structure can be dense and bushy, crooked to straight, horizontal branching, or weeping to upright form.  Matching seedling grown trees for one job can be a challenge.  New cultivars like Forum (NXSXF) and Wildfire will help keep forms consistent.

Leaves are shiny, dark green, 3″-6” long, 1.5″-3” wide, and sometimes on a reddish petiole.  Fall color can range from fluorescent yellow to orange, scarlet, or red to purple.  Usually a head turner!  Fruit is somewhat insignificant as a blueberry sized and colored drupe. Some literature suggests several insect and disease problems, but I have seen little in the Pacific Northwest.

Keep the Nyssa sylvatica on our street tree and landscape list.  You will not be sorry.  Please share comments on this or other varieties here.

Jim Barborinas
ISA Certified Arborist #0135
ASCA Registered Consulting Arborist #356
 Certified Tree Risk Assessor #PNW-0327