Are Railroad Ties Okay Around a Garden?

Creosote

• The most common form of creosote used to preserve outdoor wood comes from the heating of coal to make natural gas or coke, a cleaner burning form of coal. Creosote, or coal tar creosote, looks like black, gooey tar and has a distinctively asphalt or old petroleum smell. Painting it on utility poles or railroad ties helps those wooden items shun moisture and delays any natural rot on wood. While some of the components of creosote are sticky and repel water, others are water-soluable and will dissolve in water.

Landscape Uses

• The size, strength and durability of railroad ties provide property owners with good value and can be used for creating outdoor walls, steps or raised planting beds. They are less expensive than stone or concrete block when building structures of the same size. Laying ties end-to-end on the ground works well as landscape edging and effectively will contain both soil and mulch. They also can be used in fencing, providing a rustic look that blends with many landscapes.

Health Concerns

• The U.S. Environmental Protection Agency lists creosote as a probable carcinogen, or cancer-causing agent. People and animals are exposed through direct skin contact, inhaling fumes and consumption of residues or of the actual goo, as in the case of children licking or nibbling on treated wood particles. The risk of cancer increases with prolonged exposure. Typically, contact with creosote leads to skin rashes and irritations. Do not use creosote-treated ties around the property if the household contains children or if ties are going to be placed near the house.

Caveats

• Any water-soluble components of treated lumber do leach into the soil profile. Do not use railroad ties in proximity to edible plants. Although Montana State University cites that creosote is not fully absorbed by plant roots and distributed within the entire plant, chemical residues can attach to plant tissue surfaces. The residues are most concerning when they occur on root vegetable crops, such as with turnips, carrots, or potatoes.