Aesculus Wangii

While on a field trip surveying/assessing areas for protection in conjunction with Vietnam's IEBR (the Institute of Ecology and Biological Resources) and Peter Wharton, the Curator of the David C. Lam Asian Botanical Garden, UBC (University of British Colombia), Canada, in the north of Vietnam in the autumn of 2007. We were very fortunate in finding and collecting a good quantity of Aesculus wangii seed. Our information lead us to believe that this was the first time that any quantity of this seed had been collected for cultivation in the West.

The tree is a rare and endangered species, with a sizeable girth in time with large compound palmate leaves comprised of 5-9 oblanceolate-obovate pointed leaflets impressed with parallel venation, on very short petiolules. Bearing enormous panicles (to 45cm across at the base) of scented yellow, purple-brown spotted flowers in spring followed by large encased seed to 10cm across (my own measurement). The trees we found were large attaining 25-30m in height, situated in moist dense mountain forest. Bearing generous quantities of exceptionally large seed conkers that would have bought terror to any schoolboy intent on being a champion player in his school playground.

It became evident within a short time that the seed had only a short period of viability in the conditions we were living in. Either being attacked by moulds in moist conditions or dehydrating at an alarming rate in the dry. Our initial collection was only of sufficient quantity to fill a small bag, which we returned to the forest and exchanged for fresh nearly a month later. The exercise had to be repeated again in another month, just before my wife Sue was returning home to the UK. However on this occasion we were overwhelmed by the sheer quantity and size of the seed, not to mention the weight. Poor Sue was faced with a whopping bill at Hanoi Airport for the 40kg of excess weight she was carrying home, apart from the sheer physical handling (this was not the only large seed we had collected).

Worried by the seeds vulnerability to drying I had instructed (I was in Taiwan by then) that they should be sown immediately on arrival home. In the open ground, but under tree canopy. There I had expected the seed to germinate as the ground warmed in spring. They would have none of it, come the middle of January about 10 of them pushed their sturdy bright red stems through the soil, even as I write there are more day by day. Fingers crossed the large seed of the many species of Rehderodendron we also collected there and sown in the same conditions, will germinate at a more sensible time.

It is with a sad heart that I have to add that Peter Wharton died on June 30th 2008, at the age of only 57, due to an aggressive form of cancer. Our hearts go out to his widow Sarah as well as their children Ian, Ben and Kate.

Fortunately Sue and I had the opportunity to visit him at home with his loving family the previous Monday along with Dan Hinkley. Ironically I had long been booked to give a talk in Oregon the previous weekend.

Peter will be missed greatly by all of us who knew him, he was a wealth of knowledge, who enjoyed nothing more than sharing his vast knowledge. Well known for cutting out the bull and getting on with the job which was close to his heart, conservation at its grassroots. I in particular feel so privileged to have shared a couple of collecting trips with him as well as frustration that it ended so prematurely. The Pacific Northwest will be far poorer for his passing.

Peter more than anyone before him has encouraged us to greater achievements. He was passionate to the point of ecstatic regarding our finds and saving them from extinction. Even as weak as he was on the Monday before he died he wanted to emphasise for the last time that we should press on, with such a passion he almost fell over in his garden.

Bleddyn's Topical Tip

...All too often aerial rooting climbers are propagated from already climbing shoots, little wonder they have difficulty adapting to rooting into our gardens. We always grow our mother plants along the ground to promote terrestrial growth. Just look at common ivy in any forest for a comparison, typically it will creep along the ground in terrestrial mode before climbing a host tree. Soon changing its growth habit as it ascends a host tree.

When planting out we recommend that the plants are laid down parallel (15cm away) to the wall or host tree, burying the already grown roots from its container. It also helps to bury some of the main stem, just ensuring the new growth is protruding from the ground. This will promote terrestrial rooting much sooner, thus availing far more energy for the plant to grow. It can be remarkable how soon the new shoots creep along the ground and find its host, especially if the soil if fertile, humus rich and moist.

Our experience using this method has saved on average about 3 years in establishing such aerial climbing plants. Giving them a sound fixing to the wall from the very base, rather than being shuffled by every frustrating gust of wind rasping the soft new aerial roots.