Trilliums - Couverture souple

W. Case, Frederick; Jr., Jr.; B. Case, Roberta

Couverture souple

ISBN 10 : 1604690755 ISBN 13 : 9781604690750

Editeur : Timber Press, 2009

Synopsis

Both field guide and gardener's handbook, this volume covers all 45 species of trilliums worldwide. The authors trekked across North America to photograph the 38 American species in the wild.

A propos du livre

À propos de l?auteur

Frederick W. Case, Jr., and his late wife, Roberta, were partners in delightful plant adventures for some four decades. Hardy explorers, they trekked through swamps and woodlands to see and photograph each of the North American Trillium species in the wild. They also grew all the American Trillium species and three of the Asiatic species in their experimental gardens in Saginaw, Michigan. This book is the culmination of their expertise in growing trilliums.For many years Fred was an adjunct research investigator at the University of Michigan Botanical Gardens. Roberta was a teacher, field biologist, plant hybridizer, and orchid breeder. Now retired, Fred continues to lecture regularly on trilliums and other flowers, serves on the Michigan Technical Advisory Committee on Threatened and Endangered Plants, and is a lifetime fellow of the Cranbrook Institute of Science. He has written books on orchids of the Great Lakes region and wild flowers of the Northeast. The North American Rock Garden Society has honored him with both the Edgar T. Wherry Award and the Carlton R. Worth Award, for the contribution his numerous articles and books have made on the subject of plants.Frederick W. Case, Jr., and his late wife, Roberta, were partners in delightful plant adventures for some four decades. Hardy explorers, they trekked through swamps and woodlands to see and photograph each of the North American Trillium species in the wild. They also grew all the American Trillium species and three of the Asiatic species in their experimental gardens in Saginaw, Michigan.

Extrait. © Reproduit sur autorisation. Tous droits réservés.

"Threats to Wild Populations of Trilliums"

Picking Wild Trilliums.
It is popularly believed that picking a trillium even one time kills the plants. This is not true. Trilliums, like all green plants, obtain their food from the process of photosynthesis, the manufacture of carbohydrates from carbon dioxide and water using the energy of sunlight. The organs of food-making are the green leaves, the light energy capturing and converting agent the green pigment chlorophyll. Naturally, anything which deprives the plant of its leaves injures it. Once picked, trilliums cannot produce another set of leaves until their cold dormancy requirement is satisfied, but trilliums have large, heavy rhizomes which store a considerable amount of food. If the plant picked is of reasonable health and size, it will appear the following season. If the rhizome is large and healthy enough, it may even bloom. There simply is no truth to the statement that picking a trillium once kills it. However, our experience from our many lecture appearances and what we have written in the past indicates that some zealots ignore the facts and go right on believing the "facts" they want to believe.

Grazing by Wild or Domestic Animals.
It is true that repeated picking of the same plant, season after season before it can manufacture enough food to maintain itself, will eventually kill it. A far greater threat to most wild Trillium populations than human picking is grazing by wild or domestic animals ... Repeated grazing, unlike the one-time picking of an individual plant, takes the same plants season after season, depleting their food reserves until they die. Maintaining wild deer herds at reasonable levels will save more trilliums than all the "education" not to pick. This is not to say that we advocate or approve of wanton picking, but there simply are not that many people out picking trilliums, and young children and the uninformed will pick a few no matter what people say.

Commercial Digging of Wild Trilliums.
Commercial collecting from wild trillium populations is not a good situation, as repeated collecting of a given area can deplete parental stocks or eliminate a rare species. Nursery propagation certainly is preferable and a better conservation practice. Some propagation techniques are available, but present methods are slow, tedious, and commercially unprofitable ... Some native plant dealers offer trillium rhizomes in quantity lots at wholesale and retail. Most do not state the origin of their plants; some call them "nursery stock." To our knowledge, no true commercial quantity "propagation" takes place at the present time. The reader must realize that the term "nursery stock" may be misleading. In some states or other legal districts, wild-collected material can be kept in beds or rows for a specified period of time and then be classed as nursery stock. If no laws covering the situation exist, dealers can call these plants what they may. Most trilliums offered today were collected in the wild. When taken legally from areas slated for development, we have no objection. In fact, we encourage legal rescue operations where the plants will otherwise be destroyed anyway. It is better that the gene pool be maintained in cultivation than totally destroyed. What we object to is illegal mass collecting from wild lands.

On the other hand, the amount of wild trillium material collected and sold or exported does not, so far as we can determine, approach the numbers given by zealous conservationists, conservation lobbyists, and those who seek to block export of all trilliums or to make a political issue of collecting them ... We do not condone mass commercial collecting from the wild. Threatened and endangered species of all wildlife should be protected by law, but we also believe there should be legal means by which properly qualified, trained botanists and horticulturists can bring into cultivation seed or selected, choice individuals of desired species, multiply them, and make them available to commercial sources so that anyone interested in these beautiful and worthy garden subjects can obtain them ...

Commercial Lumbering Techniques.
The type of commercial lumber harvesting utilized can have a big influence upon native wild plant populations ... A new and, to many biologists, disturbing lumbering practice has appeared and is widely utilized in the southern United States and now in northern large private lumber company lands. In this method, the area is clear-cut. All sizes of timber may be utilized: anything not of high quality is chipped for chipboard. No trees are left. Then, the land may be burned to kill brush and eventually sprayed with herbicide "to kill weed trees." Finally, special trees, often hybrids or exotic species, are planted for a future timber harvest. This cut, slash, burn, and herbicide practice takes an enormous toll upon some native plants, alters the paths of natural succession, and may exclude the return of some native plants. For the more delicate natives, lady's slippers and other wild orchids, as for trilliums, the full effect on their populations is unknown. Any practice that totally alters a habitat usually takes out all individuals of a species dependent upon it, both adults and seedlings. With today's technology, massive machinery, and aerial spraying of vast areas with powerful herbicides, we are concerned about the impact on trilliums and other native plant populations ...
"Legal Protection of North American Trilliums"
In spite of all the dire talk and a few problem situations, most American Trillium species seem to be holding their own at present. Within the sometimes limited distributional ranges, if one enters the proper habitat, the species will be present, usually frequent, and, in the case of T. grandiflorum, T. erectum,
T. sessile, and T. recurvatum, and many others, locally abundant. Many species thrive not only in mature forest, but also in second-growth forest and brushland, and some can invade fallow fields. Except for the species identified under the U.S. Endangered or Threatened Species Act, just a few Trillium
species of very limited natural distribution may, at present, be in trouble. Only in urban areas, developments, some commercial lumber tracts, and areas of excessive human or deer population do most trilliums truly suffer and their numbers decline. With continued human population growth and all its demands upon the land, we can expect that wildflower populations of all types will be increasingly stressed and damaged. We ought to set about now, before they become endangered, to protect our native plant treasures for the future.

Détails de l'édition

• Éditeur: Timber Press
• Date d'édition: 2009
• Langue: anglais
• ISBN 10: 1604690755
• ISBN 13: 9781604690750
• Reliure: Broché
• Nombre de pages: 286
• Coordonnées du fabricant: non disponible
• Personne responsable: gpsr@libri.de; gpsr@libri.de; ; Friedensallee 273; Hamburg; 22763; Allemagne