This blog reviews the latest products, plants and innovations in gardening. It also provides a link for my many gardening friends who are members of the GardenMessenger and Seedmessenger Yahoo groups and their sub-groups that I moderate.

My Photo
Location: Australia

I am a semi-retired UK botanical garden curator and former international horticultural consultant, who has worked extensively in Europe, the Middle East, North America and Australia. I spend part of the year in Australia and part in Europe, mainly due to family and work commitments. I earn my living from writing and editing Internet copy, articles and books. I have written over fifty books on gardening and have been translated into twenty-four different languages. I am a former UK Garden Writer of the Year and a previous Quill & Trowel Award Winner from the Garden Writer’s Association of America. I am interested in developing gardening communities on the Internet and I manage the popular GardenMessenger Yahoo group, along with its various sub-groups like PondMessenger and SeedMessenger. I also edit International Water Gardener and its associated regional web-sites.

Tuesday, June 20, 2006

Defeating Dutch Elm Disease, Developing Bio-based Pots and Pine Wood Growing Bags

The original 'Jefferson' elm on the National Mall in Washington, D.C.

Researchers in the US are getting on top of Dutch Elm Disease (DED), at least they are showing positive outcomes in outwitting the deadly disease, which was accidentally imported on logs shipped from France to Cleveland, Ohio, in 1931, and which by the 1980s had wiped out around 77 million American elms. To combat this exotic and deadly disease, caused by the fungus Ophiostoma ulmi, researchers have screened thousands of American elm trees for DED resistance. The research team have taken great care, and enough old specimens have been located and kept alive to provide the germplasm necessary to develop DED-tolerant trees. Much of this work has been done by Agricultural Research Service (ARS) scientists with the U.S. National Arboretum in Washington, D.C.

The arboretum’s tree-breeding project was led, until his 2005 retirement, by geneticist Denny Townsend, who worked with horticulturist Susan Bentz, in the ARS Floral and Nursery Plants Research Unit (FNPRU) at Glenn Dale, Maryland. In 2005, the newest American elm - named ‘ Jefferson’ - was released jointly by ARS and the National Park Service (NPS), after collaborative screening tests by Townsend and NPS plant pathologist James L. Sherald showed it to have an outstanding level of DED tolerance. It was cloned in 1993 from the original tree, a survivor of about 600 elms planted on the National Mall in Southwest Washington in the 1930s. Jefferson was thought to be a hybrid elm until DNA tests performed at the arboretum proved it to be a true American Elm, Ulmus americana, much to the relief of purists. This sturdy elm grows in the typical vase shape up to 20m (68ft) tall. Its leaves turn dark green earlier in spring and stay dark later in autumn than most other elms. Jefferson has broad U-shaped branch unions, rather than narrow V-shaped ones, has attractive bark, and can be propagated by softwood cuttings.

FNPRU research leader John Hammond regards ‘Jefferson’ as a good street tree because it can withstand pollution from city traffic and has wide adaptability, growing in USDA plant hardiness zones 5 through 7. While this durable, DED-tolerant elm may once again fill US parks and grace street sides with true American elms, ‘Jefferson’ will not be available to home gardeners for about four years. But specimens can be seen on the National Mall, next to the old Smithsonian Building, and soon at the arboretum. Efforts are under way to propagate quantities for nursery co-operators. Two other DED-tolerant elms developed through ARS tree breeding, ‘Valley Forge’ and ‘New Harmony’, are already quite widely planted.
Photo: SE Bentz ARS

New Growing Bag Use 100% Pine Wood
EkoFibre in the UK are producing growing bags that contain 100% high quality lignin cellulose pine wood fibre's which are harvested especially for this purpose from FSC certified sustainable forests.

For the above click here.

Developing Bio-based Pots
Plant pots made from farm wastes could one day be a boon to both home gardeners and the horticultural industry, as well as the environment. The Agricultural Research Service (ARS) and the Horticultural Research Institute (HRI) of the American Nursery and Landscape Association are working together to create biodegradable pots for nursery production.

New Free Pond Guides from Mitre 10 New Zealand
Mitre 10 have produced two useful practical on-line guides for newcomers to water gardening.

For the above click here.

Design News - Hampton Court Preview Garden
Hadlow College,Kent - CaCO3
Chalk (CaCO3) - what does it mean to you? Industrial cement works or Kentish chalk downland?

For the above click here.

A New Apricot Rootstock from Bulgaria
Research in Bulgaria to find the ideal rootstock for apricots started in the 1970s. This work has just come to fruition with the release of the Prunus myrobalan rootstock ‘Aidemirska’.

Raspberry ‘Valentina’
‘Valentina’ is an exciting new raspberry cultivar....

New Celosias
There is a new series of Celosias available to home gardeners. This series comprises four cultivars, each of which as been recognised by either Fleuroselect or All America Selections for all round excellence.

For the above click here.

Happy Gardening



If you have enjoyed this publication, you may also like to visit the monthly SeedMessenger gardeners’ seed saving and seed exchange blog click here.
and the weekly water gardening blog PondMessenger click here.

To join the GardenMessenger gardening community
click here

To visit the SeedMessenger seed exchange web-site
click here

Directory of Gardening Blogs


Post a Comment

<< Home

Site Meter