Paulownia

My neighbor Larry Whiteley and his 10-year old granddaughter Anna Whiteley showed up after a youth season deer hunt with an unexpected trophy from our timber stand improvement.  It was time to "Stump the Master Naturalist", something that is not at all difficult to do.  The leaf measured 22" across and the stalk was moist and somewhat hollow in the center.  It looked exotic, more likely to live in a jungle.

An email to our favorite MDC forester brought an immediate response, (I think she was sitting there waiting for my next question). "Paulownia!"  Since it was on our land, we knew it had to be an invasive species.  Right again.

The Princess Tree, Paulownia tomentosa, was introduced as an ornamental and landscape tree around 1840.  The wood has commercial uses as quality furniture wood, veneer, carving wood and for musical instruments in addition to its pulp wood potential.

"Royal Paulownia is a native of China has a most dramatic, coarse-textured appearance, with its huge heart-shaped leaves and large clusters of lavender flowers in the spring. Paulownia flowers are borne before leaf emergence so they stand out nicely, especially against an evergreen background. With a rapid growth rate, Princess Tree can reach 50 feet in height with an equal spread in an open landscape."  About.com

So why are they invasive?  Part of the answer it found in NPS Least Wanted.

"Princess tree can reproduce from seed or from root sprouts; the latter can grow more than 15 feet in a single season.  The root branches are shallow and horizontal without a strong taproot.   Seed-forming pollen is fully developed before the onset of winter and the insect-pollinated flowers open in spring.  A single tree is capable of producing an estimated twenty million seeds that are easily transported long distances by wind and water and may germinate shortly after reaching suitable soil.  Seedlings grow quickly and flower in 8-10 years.  Mature trees are often structurally unsound and rarely live more than 70 years."

Click to enlarge

How did its winged seeds get up to a heavily wooded hillside miles from any garden?  Who knows?  How invasive it is only time will tell.  However, if this picture is any indication, they are here to stay in our urban environments.  Lets just hope that they can be converted to biofuel.

See an extensive collection of pictures at Invasive.org
Wikipedia on Paulownia