[...]... and match to the fungus The airborne spore of Cryphonectria is a sexual spore that is generated after the microorganism has been fertilized by a compatible mate The sexual union is consummated when a conidium from one strain of the fungus (designated the male) fuses with the cells of another strain (the female) already established in the bark At least in the laboratory, a pair of conidia 14 Landscape... 18 Landscape Architect Walmarts, and Home Depots, the reversion of farmland to woodland has enlarged the green canopy in the eastern half of the country A handful of apparently healthy chestnuts are dotted throughout the original range of the species These plants are of great interest to researchers because there is a slim chance that they may have acquired some resistance to the fungus Unfortunately,... disease had been identified in New Jersey, Maryland, the District of Columbia (visible from the of ce windows of the USDA scientists), and Virginia Others had reported blight in Alabama and Georgia Because all of these outbreaks occurred less than a year after its appearance at the zoo, the zoo couldn't have acted as the original source—no fungal disease could spread that fast The origins of the developing... came close to competing with Californian coastal redwoods that can tower more than 110 meters But nothing grew taller than Castanea dentata from Maine to Alabama in a 500-kilometer-wide diagonal of deciduous jungle spined by the Appalachians The impact of the near extinction of the tree can be assessed, of course, from many perspectives Chestnuts served as a staple construction material for American... Finally, he named the fungus: Diaporthe parasitica sp nov (sp nov for species nova or new species), which was later changed to Endothia parasitica and is now known as Cryphonectria parastica (fig 1.3) (I use the modern name for the rest of this chapter.) Cryphonectria parasitica belongs to a group of fungal pathogens that cause a variety of diseases including cankers of soybeans and peach trees, stem-end... part of the Ohio—Gallia County—has spectacular scenery; a gorgeous mix of well-groomed farmland and forest that merges with the Wayne State National Forest to the south He showed me several locations where he had planted the saplings from Los Alamos All the trees showed disease symptoms The radiation hadn't created any mutants capable of rebuffing the fungus 20 Landscape Architect Radiation is one of several... surrounding olive-green bark As the cambium dies, the surface of the branch sags in some areas and swells and cracks open in others The Landscape Architect 13 infected areas are called cankers.22 Within a short time interval, perhaps no more than three weeks, the fungus begins producing spores called conidia from pustules that appear as pinhead-sized orange dots: the color of raw sienna, turning a dark umber... other animals Acorns replaced the chestnuts after the blight, but fruiting in oaks is subject to annual variation, which leaves animals up the proverbial creek Landscape Architect 7 on a regular basis Overall, one can say with some justification that the chestnut blight wasn't a good thing for North America That was one of the conclusions reached by delegates at a conference on the disease called by the. .. in Philadelphia Treatment of the blight was a serious political issue Before the arrival of the fungus, the value of the chestnut in Pennsylvania was estimated at $70 million, which is equivalent to $1.3 billion in today's money.11 Having dealt with New Jersey, the chestnut fungus had already infected trees in eastern counties of Pennsylvania and was racing westward across the Appalachians.12 The epidemic... Cryphonectria parasitica From W A Murrill, Journal of the New York Botanical Garden 7, 143–153 (1906) was useless Reports of diseased trees arrived from all along the eastern seaboard, and another chestnut species called the chinquapin (Castanea pumila) was also falling prey to the blight Merkel suggested that diseased trees be cut as soon as possible so that their lumber could be salvaged before further decay.5 . than Castanea dentata from Maine to Alabama in a 500-kilometer-wide diagonal of deciduous jungle spined by the Appalachians. The impact of the near extinction of the tree can be assessed, of course,. of American chestnut, Castanea dentata. From F. A. Michaux, The North American Sylva; or, A Description of the Forest Trees of the United States, Canada, and Nova Scotia. Considered Particularly. than a year after its appearance at the zoo, the zoo couldn't have acted as the original source—no fungal disease could spread that fast. The origins of the developing catastrophe were a