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Trees and Plants
Spring Valley EcoFarms features a rare and eccentric collection of plants from Guangdong, China
. The collection was assembled through collaboration with the University of Georgia State Botanical Garden.
 The Princess Tree
The Princess tree, Paulownia tomentosa, is a fast growing tree occasionally seen along roadsides and in yards of the Southeast. The spectacular purple flowers that appear in the spring resemble those of purple wisteria. Because of its large leaves, people often think it is a catalpa. Its seed pod, containing hundreds of seeds, is oval, and is flexible, somewhat like styrofoam. It is native to China, and legend has it that in the 1800s, the seed pods were used as packing material for plates, and entered the U.S. in boxes shipped from China. The wood of the tree is light and strong. In Japan, it is used for molding, and veneer. During WWII, the fuselage of Zero airplanes was made of paulownia. The best quality wood is used for musical instruments and fine furniture. A traditional Japanese father would plant a paulownia tree when a daughter was born, and when she was ready to be married, he would cut the tree and build her a chest to keep her valuables.
The terminal buds of Paulownia tomentosa are killed each year by frost, and neither of the two uppermost lateral buds which develop show apical dominance. Unless one of the buds is pruned every year, the tree develops a crooked or forked bole, undesirable for foresters. In the late 1980s, Prof. Huo Yingqiang brought seeds of Paulownia fortunei to the U.S. as part of an exchange program with the Georgia State Botanical Garden. We planted several hundred trees at Spring Valley EcoFarms, and compared their growth to that of Paulownia tomentosa and Paulownia elongata. In contrast to these latter two species, one of the two lateral buds of P. fortunei is always dominant, and consequently the natural shape of the tree is straighter than either P. tomentosa or P. elongata.
The species Paulownia elongata may have originated in China as a cross between P. tomentosa and P. fortunei, and then became geographically isolated for a long enough time to be considered a separate species. The flower color of P. tomentosa is purple, that of P. fortunei is white, and P. elongata is a pinkish blend of the two colors. Apical dominance in P. elongata also seems to be a blend of that shown by P. tomentosa and P. fortunei, at least on our experimental plots.
The American Paulownia Association promotes the princess tree as an alternative crop for Southeastern Landowners. In their Sept. 2007 bulletin, they claim it can produce 16 inch diameter logs useable for plywood or oriented strand board in 11 to 13 years. Our observations suggest that this may be true on the inner coastal plain of Georgia, where the soils are sandy and well drained. In the Georgia Piedmont, growth is slower, due to the heavy clay soils that slow down root growth and water percolation. The Japanese actually prefer slow-grown paulownia, because its smaller growth rings result in sturdier wood.
We tried interplanting Paulownia tomentosa with two slower growing species, white oak and green ash. The idea was that the differential growth rates would reduce competition. The paulownia would grow rapidly early in the cycle, while the oaks and ash were establishing their root systems. Then when the paulownia was harvested, it would result in a “release” for the oaks and ash, because these trees with their root systems well established, would react quickly to the newly available light. The system was working well until after 10 years when we decided to let our cattle and horses graze underneath the canopy. We went away for Christmas break, and when we returned, they had girdled all the paulownia. Rather than chip the trunks, we sawed them in half and laid them on the ground. The horses did an excellent job of debarking. We now plan to use the wood for split rail fencing. Our oaks and ashes are now about 25 feet tall. The paulownia that were killed back will sprout again, and next year we will observe how well they do underneath the canopy of the oaks and ashes.
We have tried all kinds of coatings for the bark to prevent the livestock from girdling it, but nothing stops them. The only thing that works is wire mesh. But grazing by livestock has not been our only problem. Last spring, we had a severe “Easter frost”. The paulownia had already leafed out, and the frost killed them back. In a month or so, many of the trees sprouted from the base. We began cutting the sprouts, and feeding them to the livestock that had been moved to other pastures. It turned out to be a good feed supplement, because by August, the drought had dried up most of our grass. What is in the bark and leaves of paulownia that livestock crave remains a mystery. The horses will gnaw through the dried bark of larger trees just so they can get at the cambium (inner bark). And the cattle will push over small trees to get the leaves.
Paulownia is sometimes criticized as being an invasive species. However, it is no more invasive than other pioneer species. In our fields that we have set aside for prairie restoration, loblolly pine is much more of a problem. Both species do well in open sunlight, but are shaded out as later successional species such as oaks and hickories become established. We will continue to experiment with them at Spring Valley EcoFarms as a “nurse” species, that is, as a species that will ameliorate the hot summer sun so that other species can more easily survive beneath their light shade.
Loropetalum
.jpg) The soils and climate of Guangdong are very similar to the soils and climate of Georgia
, therefore the conditions are ideal for plants like the Loropetalum chinens. There are multiple varieties of Loropetalum and they are all coveted for their star-like flowers and robust qualities.
Mr. Huo YingQiang, who has been working with the Spring Valley EcoFarms staff since 1993 has been propagating many plant varieties that have gone on to have great .jpg) commercial success in the gardening and landscaping market, but the "professor" as he is known at the farm, only cares about one thing: the act of planting, reproducing plants and studying their qualities. Very few people know the recipe for the 100% natural fertilizer that makes professor's plant reproduction so easy, successful and low cost. One thing is for sure…it’s not just any old lemonade.
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