The Bridgeport evening farmer., 1911-11-04
Deadly Chestnut
 Bark Disease Over $25,OOO,0OO Damage
 Caused Already Government Tells How to Gain Control Over It's Spread = Necessary for Each State to Legislate Against It.

Against It.
 The deadly chestnut bark disease,
 which already has caused a loss Of
 some $25,000,000 and threatens to de-
 vastate all chestnut trees in the coun-
 try, unless stopped, is made the sub- ject of an interesting bulletin, Far
 mer's Bulletin No. 467, issued by the
 United States, Department of sAgricul
 ture. The bulletin is written by Ha-
 ven Metcalf, patho.ogist in charge of
 investigations in forest pathology, and
 J. Franklin Collins, forest pathologist
 of the bureau of plant industry.
 The disease was first recognized as
 a serious disease in the vicinity of
 New York city in 1904, although there
 is reliable evidence that it was present
 on Long Island at least as early as
 1893. Its origin is unknown, but there
 is some evidence that it was import
 ed from the orient with the Japanese
 chestnut. Whatever may have been
 its time or place or origin it is certain
 that it has spread into at least ten
 States. In the vicinity of New York,
 and through adjacent counties it has
 killed practically all chestnut trees,
 and all trees in a much larger area
 are affected. Scattering points of af-
 lection are known to occur through out the country from the northern
 border of Massachusetts and from Saratoga County, N. r., to the west ern border of Pennsylvania and the southern border of Virginia.
 As far as Is now known. the disease is limited to the true chestnuts, that is, to the cultivated varieties of the genus Castanea. The American chest nut, the chinquapin, and the cultfvat- ed varieties of the European chestnut are all readily subject to the disease. Only the Japanese and perhaps other east Asian varieties appear to have resistance. It can be positively stat ed that the bark disease is not now chestnuts. beeches, hickories, Or the go!den-leaf chinquapin of the Pacific coast
 The disease appears ultimately to exterminate the chestnut trees in any locality which it infests A survey of 16,695 trees were killed in the $50 acres of woodland in this park alone" Three years ago the financial loss in and about New York city was esti- mated at between $5.000.0O0 and $1O,- 000, GOO. Writers regard 25,000,000 as conservative estimate of the loss up to 191k In many localities the great est damage has been among chestnuts grown for ornamental purposes, which have value greatly in excess of their value as lumber.
 The disease is caused by a fungus parasite known as "Diaporthe parasf- tica Murrill." When any of the mi croscopic spores of this fungus gain entrance into any part of the trunk or limbs of a chestnut tree they give rise to a spreading "sore'' or lesion, which soon girdles the tree. If the part attacked happens to be the trunk the whole tree is killed, perhaps in single season. If the smaller branches are attacked, only those branches are killed. and the remainder of the tree may survive for several years.
 Some of the symptoms are quite prominent Limbs with smooth bark attacked by the fungus show dead, somewhat discolored sunken areas Occasionally with a raised margin), which continue to enlarge and soon become covered more or less thickly with yellow, orange or reddish brown spots about the size of pinhead. These spots are the pustules of the fruiting fungus. In damp weather or in damp situations, masses of the spores are extruded in the form of long, irregularly twisted strings or horns, which are first bright yellow to greenish yellow or even buff, becoming darker with age. If the lesion is on the trunk or large limb with very thick bark there is no obvious change in the appearance of the bark itself, but the pustules show in the cracks and the bark often sounds hollow when tapped. After the smooth parked limbs or trunks are girdled the fungus continues to grow extensively through the bark, sometimes covering the entire surface with reddish brown pustules.
 hyoro o1h frrrr crir the leaves change color and sooner or later wither Such branches can hardly be mistaken for anything else, except in certain localities where the work of twig-girdling insects may produce a similar appearance In the spring. In case the girdlfng is com pleted late in the season, the leaves of the following spring assume a vel Jewish or pale appearance and do not develop to their full size. If the girdling is completed between spring and midsummer the leaves may at tain their full size and then turn somewhat characteristic reddish brown color which can be detected | at a long distance. The chestnut burs on a spring-gi -girdled branch may or may not attain full size. These burs persist on the tree through | the following winter, thus producing the only symptom which is at all con- SplCuOuS SuS lCohACSS oSoSOAi. | Perhaps the most easily seen as well | as the longest persistent symptom of the bark disease is the prompt de- l velopment of sprouts or suckers, on | the trunk of the tree and at it's base | or somewhat less frequently on the smaller branches.
 The disease is spread by the spores of the fungus, of which there are two kinds Both. appear to be sticky and 1 .here is no evidence that they are transmitted by wind except where they | may be washed down into the dust 1 and so blown about with the dust. The ,ain easily carries them short distan- ,es, particularly from twig infections to the lower parts of trees There 1 s strong evidence that the spores gre spread extensively by birds, es- oecially woodpeckers, and also by in- ,ects and various rodents, such as squirrels. The disease is carried bod ly for considerable distances in tan park and unbarked timber derived rom diseased trees. One of the most prolific sources of general infection has ,een the transportation of diseased nursery stock from infected o uninfected localities.
 When the spores have once been car ,ied to a healthy tree, they may de- yelop in any sort of hole in the bark which is reasonably moist. These nav he wounds or mechanical injur-