Black Ash

(Fraxinus nigra)

There are five species of ash that are commonly logged in Eastern North America.  The most popular is White Ash, known for its predominant white sapwood.  Pumpkin, Blue and Green Ash lumber is usually mixed in and sold with White Ash.  That leaves Black Ash as the outlier, the only ash species that can be separated from the rest.

Black Ash is a small to medium size tree usually growing to 65 feet in height with a trunk diameter of 1 to 2 feet.  In Canada, it can be found from Newfoundland west to Manitoba.  In the northeastern United States, it grows south to Virginia and as far west as Illinois.  Black Ash has a distinct preference for wet habitats and is commonly found in swamps.  Where it grows can have a profound effect on the resulting lumber.

The sapwood is usually a dull white, not the brilliant white found in White Ash.  The heartwood is brown and can vary in size dependant on how fast the tree grows.  The wood is straight grained with a small amount of figured wood (usually curl) occasionally present.  Black Ash is a ring porous wood with a medium to coarse texture.  This is a result of the very large early wood pores in the growth rings of this species.

Fast growing Black Ash tends to have wide growth rings with a greater proportion of latewood.  The resultant wood is heavier and stronger.  These trees also have large amounts of white sapwood.  Black Ash from northern areas and from wetter habitats have a tendency to grow slower.  The growth rings are smaller with a higher amount of early wood within each ring.  This weakens the wood.  Slower growing trees will also be mostly made up of dull brown heartwood.

Black Ash shares similar working characteristics with White Ash.  Tools should be sharp to work with this strong wood.  It glues and finishes well.  Being ring porous, it is attractive when stained.  It can be finished to mimic oak.  Lumber sizes are smaller than White Ash so large panels will require more pieces.  Nails and screws should be predrilled.  It is often steam bent when green for all sorts of curved work.

Black Ash is strong and has great shock resistance, so it is often used for tool handles, baseball bats and rackets.  It is a good utility wood for boxes and is also used for rustic flooring.  Black Ash is well known for its use in woven baskets.  It can also popular choice for electric guitar bodies.  Both of these uses derive from the strong dense qualities unique to the Black Ash.

To make woven baskets, the end grain of green Black Ash logs is pounded with a mallet-like tool.  This will crush and collapse the weak earlywood allowing the harder latewood to be peeled off in long strips.  These strips are then collected and woven into baskets, chairs, etc.  This technique’s success relies on the large early wood pores found in Black Ash.

Similarly, the large early wood pores and tight growth rings of Black Ash yield a light and resonant wood suitable for electric guitar bodies.  “Swamp ash” is a term that is often used to describe these woods.  There is also a lot of debate among luthiers if the term applies to Black Ash or other ash species with similar growth rings.  If you are purchasing swamp ash, only a close examination of the growth rings will tell you what species it is.

Black Ash is usually inexpensive compared to other ashes and hardwoods. The price you pay will also be determined by geography.  Fast growing material from southern growing areas commands a higher price due to their large white sapwood and higher strength.  Specialty lumber dealers are your best bet to source this material.

Finally, you can’t discuss Black Ash without discussing the Emerald Ash Borer.  This invasive pest is decimating all ash populations.  Black Ash is particularly prone to attack.  This species is now considered critically endangered and we are expected to lose at least 80% of the trees.  For now, Black Ash will continue to be cut in order to remove diseased trees before they degrade.  There is no treatment or technique that will stop the borer.  The final story of the Black Ash may well be a reminder on how fragile our forests really are.


Leave a Reply

Your email address will not be published. Required fields are marked *