Paulownia tomentosa has a way of seducing gardeners into giving it a home and even treating it like it belongs in the landscape. Unwitting gardeners will be surprised that what they think is a giant sunflower with giant leaves starts growing again the next year. The tree grows as much as 8 to 10 feet per year and can go from seed to mature, blooming tree in just a few years. The blooms are huge, purple and pretty, which is why you can still buy these plants in certain garden catalogs.
But those blooms give way to prickly, messy seedpods full of seeds bent on domination. They find maintained lawns and gardens an excellent place to set up shop. It amazes me to drive through the area and see people treating these beautiful monsters like they belong in the landscape, with careful pruning and care just like other trees. These trees spread to choke out native trees and plants, though, so they earn a spot on my enemies list.
Tree of heaven
Another noxious tree with a cute name, tree of heaven (Ailanthus altissima) is an opportunistic species that outcompetes native trees and fills in forest canopies faster than other trees can grow. Its name comes from the fact that it does reach for the heavens so quickly. It resembles sumacs and other trees, so folks might not know that they have an enemy in their midst. This tree propagates both by seeds and by roots.
Its secret weapon is ailanthone, an allelopathic compound that it releases from its roots to kill any competition that finds its way into the root zone, much like black walnuts do. Its roots can also find their way into cracked sewer and water lines.
This tree does, however, have a good side (when it is not in your yard or forest): It grows well where other plants do not, such as acid mine drainage fields and mine sites. It tolerates shockingly low pH levels, absorbs sulfur dioxide through its leaves, resists cement dust and coal tar fumes, can live in high-salt and low-fertility soils, withstands drought and will suck up mercury from the soil. In other words, it is a survivor. When the world ends, there will be only cockroaches and Ailanthus altissima.
• • •
I will be giving workshops at the upcoming Mountain State Art & Craft Fair in Ripley on how to grow more food (and in less space) to save time and money. I will present "Making the Most of Your Garden Space" at 1:30 and 3:30 p.m. July 5 and 10 a.m. and 2 p.m. July 6.
John Porter is the WVU Extension Service agent for agriculture and natural resources in Kanawha County. He may be reached at john.por...@mail.wvu.edu or at 304-720-9573. Twitter: @WVUgardenguru.