By Susan and Biff Andrews

If you spend enough time in the woods, eventually you will come across a “pregnant” tree — at least one that seems to be pregnant.

A large rounded growth may protrude from the trunk, usually the size of a basketball, but sometimes much larger — even four to five feet in diameter.

This is not a “state of health” but a state of illness. The tree has suffered an injury or an illness, and the resultant bulge is called a burl. But don’t think this is a sad situation. Burls are highly coveted by wood turners.

A burl is an abnormal growth on a tree. The tree grain is deformed due to an injury to the tree and subsequent scabbing over, or due to illness, a tumor or infection within.

It is a collection of small knots from dormant buds. When cut open, they reveal unique wood grain full of colors, swirls and other interesting patterns.

There are basically two causes of burls resulting in two different patterns. If the tree has suffered an injury — from a fallen neighbor tree, a broken-off branch or a “frost split” from a hard freeze after sap is already running — the tree “layers” protection over the wound. The patterns of the protecting layers tend to be fairly regular in nature, but swirling. This is a “layered burl.”

An “eyed burl” is the result of an illness in the tree — a tumor, infection or insect damage that causes a collection of dense knots within each other or side by side from each other.

The eyed burls are more valuable, especially when turned by a woodworker into a bowl.

These burls can be valuable. If you go online, you will find “raw” burls for sale from $25 to $500, depending on size, type of wood and pattern of the grain.

But don’t just pull out your chainsaw and whack any burl you come across. If it’s on your land, it’s your tree; if it’s not, then you’d better be getting permission.

When you eventually harvest the tree, cut six inches above and below the burl and allow it to dry thoroughly. If it’s too heavy to move, slice off the back side. Do not just do “cow pie” slices off the side of the tree and try to dry them separately.

When dealing with the burl after drying, decide if it will be used for boards (cut in a block) or for turning into a bowl (cut into a round).

The most common uses for burls when fashioned into beautiful finished wood products are bowls, wood inlays, box lids and veneers. Go online to see examples of car dashboard inlays, bowls both large and small with regular or irregular rims, guitar surfaces, tabletops and more. Many of these cost thousands of dollars.

But don’t pirate someone else’s burled tree. Don’t whack one from a tree in a state or national forest.

Such poaching is a real problem out west. Let’s not let it become one here.

Many farm markets, including the Smithfield and Williamsburg ones, have booths promoting burl products from local woodworkers. Stop by to look, chat and buy.

If you have a major burl on your property and want to profit from it, offer it to one of these woodworkers for a fair price.

But most of all, as you walk through the woods, be aware of what is around you, and the wonders you may encounter — even pregnant trees.

Susan and Bradford “Biff” Andrews are retired teachers and master naturalists who have been outdoor people all their lives, exploring and enjoying the woods, swamps, rivers and beaches throughout the region for many years. Email them at b.andrews22@live.com.