The artificial tree has come a long way, in terms of realism, since the imitation Tannenbaums of 19th century Germany, with their green-dyed goose feathers for leaves. Today's fake greenery has the potential to befuddle even the professionals. And tomorrow's synthetic trees might not only fool the eyes but also fuel your home.
Surprisingly authentic for being so "low-tech," silk replica trees are popular no-maintenance alternatives to the real things. You'll find them sprucing up restaurants, hotels and shopping malls wherever you go. Usually, only the leaves of these trees are made of silk. Trunks and branches can be fashioned of plastic or wood. As these materials might cause a fire hazard on their own, better products incorporate special fire-retardant chemicals. Products for outdoor use include the extra step of anti-UV treatment to prevent fading and deteriorating in the sun.
Polyurethane Elastomeric Bark
A company called Replication Unlimited offers a technology they call a "Flex-Bark system." This involves taking a mold from the real tree you want to imitate and using it to create flexible sheets of polyurethane elastomeric material to cover any artificial trunk so realistically that "it can easily fool the best botanist." The resulting product also is lightweight, weather-resistant and fire-retardant.
Polyvinyl Chloride Needles
Most of the natural-looking artificial Christmas trees you've probably seen have needles made from polyvinyl chloride (PVC). Manufacturers slit large sheets of the stuff into thin, flat strips.
Higher-end synthetic Christmas trees use multihued polyethylene (PE). This material is poured into a variety of molds. Companies such as Holiday Bright Lights, Balsam Hill Christmas Tree Company and Frontgate use different sets of molds for each species of tree being imitated, such as Noble fir, Vermont spruce or Scotch pine. And each species might require several molds so the resulting segments don't look unnaturally clone-like. Further touches of realism come from hand-painting the undersides of the PE fronds.
Tree-lined sidewalks and gently shaded park spaces add natural beauty to towns and cities. They also freshen the air, exchanging carbon dioxide for clean oxygen. But in the near future, urban green spaces could fulfill additional purposes: renewable energy generation. A company called Solar Botanic has been developing artificial trees whose "Nanoleaves" contain arrays of tiny photovoltaic, thermovoltaic and piezovoltaic receptors. These take in light from the sun and ambient heat, converting them to energy. Energy also is generated every time the wind rustles these nanoleaves. And their visual resemblance to real leaves is uncanny.