8:00 a.m. Shuttle departs Hilton Garden Hotel to Morris Arboretum
9:00 a.m. Welcome—Paul Meyer, The F. Otto Haas Director of The Morris Arboretum of the University of Pennsylvania
9:10 a.m. How to find your way in the multitude of Japanese Maples - Cor van Gelderen
There are so many Japanese Maples nowadays, that many of our interns become disheartened, at the sheer sight of them. How are they ever going to understand, let alone know, all these cultivars. So they give up, before even having started. And I feel that the same feeling overcomes many of our customors as well. With that experience in my mind I have tried to come up with a solution. Grouping them in logical groups of related cultivars helps. But defining logical groups is a bit of a challenge. In this lecture I will try to define logical groups of related cultivars and present them. Images of these plants will underline the advantages of cultivar groups.
10 a.m. Break
10:15 a.m. The evolution of the reproductive organs of maples in comparison with some phylogenetic trees of the genus Acer - Piet deJong
The original inflorescences and flowers of maples have shown a whole series of reductions during the evolution of the genus. The original heterodichogamous flowering has resulted in some taxa of the genus in complete dioecy and wind pollination. A number of recently published phylogenetic trees show that the earlier divisions of the genus mainly based on morphologic characters of flowers and inflorescences were monophyletic sections and series. Some phylogenetic trees, however, show unexpected variations.
11:00 a.m. Acer section Platanoidea - Recent Asian introductions into cultivation - Dan Crowley
In recent years there have been a number of Asian introductions to cultivation of members of Acer section Platanoidea. Among these are plants causing considerable confusion in terms of their identification and correct nomenclature. For example, some of the introduced material listed under the same collection number has been identified as belonging to different taxa by different individuals/institutions and are growing in various botanical institutions under different names. Recently published literature recording these inaccuracies further contributes to the confusion among this interesting group. Dan is undertaking a project to ascertain which taxa are in cultivation and under what names. The correct identity of those in cultivation will be established, with the work then extending to the other members of the section and eventually culminating in a taxonomic revision of the section. Here he will present the status of the project so far.
1:00 p.m. Depart for Tour of the Scott Arboretum of Swarthmore College
2:00 p.m. Tour of the Scott Arboretum
4:00 p.m. Depart Scott Arboretum
5:00 p.m. Return to Hilton Garden Inn Hotel, dinner on own