On a typical tree, only the core wood is suitable for a railroad tie. One mature tree only produces 2-3 wood railroad ties; which means 1,300 trees are cut down to supply every mile of railroad track. To replace existing ties in the 140,000 miles (approx.) of track in the U.S. it would require cutting down around 182 million trees. Each year, 20-25 million railroad ties are replaced across the US; representing 6-8 million trees.
To increase their lifespan, traditional wood ties are treated with creosote or other non-organic chemicals for preservation. Creosote is a known carcinogen with so many harmful effects that the EPA banned it in most products in the 80’s with the exception of the Railroad Industry; due to a “hardship” because there currently is no viable alternative to creosote-treated wood railroad ties. Although its use is still allowed, continued pressures from the EPA and environmental groups have pushed the rail industry to search out alternative railroad ties. Currently, alternative railroad ties, including concrete ties, represent only 7-9% of the railroad ties installed.
Rubber ties also decrease noise and vibrations in the track potentially limiting the need for sound attenuation in sensitive areas.