PHONY Peach Disease Control is Promoted by Destroying Wild Peach Trees

Although the peach is not native to the United States, the climate and soil of the Southeastern States are so well adapted to its needs that it became readily naturalized there at an early date. From the extensive home and commercial orchards that were planted, trees have escaped from cultivation and produced prolific numbers of "wild" seedlings. Today, in Georgia alone there are many millions of these wild seedlings, ranging from small bushes to old trees 30 feet or more in height, scattered throughout the State, and similar conditions exist over practically the entire region. Occasionally these seedlings are found on terraces, particularly in old, abandoned fields, and along fence rows. More commonly, however, they grow along the edges of woods, intermingled with elderberry, persimmon, alder, ‘and sweetgum, and frequently almost smothered with honeysuckle.  In such positions they are inconspicuous, and it is seldom that a landowner realizes their presence, even if he is an orchard owner.  Yet these wild peach trees constitute a serious menace to the succesful operation of a commercial peach orchard, because they are liable to attack by all the insects and diseases that attack cultivated peaches and serve as a reservoir of infestation and infection for the commercial orchards, no matter how well these are cared for.

Within 2 years after the commencement of the campaign to eradicate the phony peach disease, it was found that numerous orchards that had been thoroughly cleaned up were being reinfected from some outside source. Surveys and careful scouting around such plantings brought to light the presence of infected wild peach trees growing near the orchards, and it was evident that the disease could not be controlled permanently in the orchards unless it was also controlled in its wild hosts.

First discovered during the nineties, the phony peach disease has already caused tremendous losses to growers 1n central Georgia. Prior to the commencement of the eradication campaign, in 1929, it had become so prevalent in many orchards as to bring about the abandonment or destruction of over a million trees and had forced several growers into bankruptcy. The disease has not restricted its ravages to one locality, however, but has been steadily spreading and increasing in importance, until it now occurs in 13 States. It may prove to be as serious throughout the country as it has already shown itself to be in central Georgia.

Thus the future of the peach industry of the country might well depend on the control of the phony disease in wild peach trees. An annual inspection of these millions of seedlings was an obvious impossibility. The trees were worthless, even when not harmful, and the obvious thing to do was to destroy them outright, but this could be done only by means of large forces of laborers. No appreciable good effect could be anticipated with the inspection force available for the work.

When the situation appeared most hopeless, the Emergency Relief Administration set up an organization to furnish immediate work for thousands of the unemployed. Among other Federal projects, they authorized one for the eradication of wild peach trees in Georgia and Alabama, where the phony peach disease is seriously prevalent, and where there are large commercial plantings or important peach-growing nurseries.

   In Georgia the Civil Works Administration furnished a force of 948 men, who worked in 42 counties. In Alabama 111 men were employed, and work was carried on in 3 counties. The projects were set up shortly after the middle of December and continued through February 15, at which time the Federal projects terminated. Beginning on February 16, State projects were set up, furnishing 448 men in 12 counties in Georgia andp 61 men in 3 counties in Alabama. Work ceased in both States on March 29.

Results of Campaign Satisfactory

These forces destroyed a total of 4,724,659 trees, 4,248,802 in Georgia and 475,857 in Alabama. While it was not expected that every wild tree could be found and destroyed in a single inspection, the results of this first campaign were very satisfactory. In a few counties the majority of the seedlings were eradicated, and in all of them a good proportion of the wild trees growing close to commercial orchards were removed. Because of the long incubation period of the phony peach disease, the direct effect of this work on the spread of the disease will not be evident for 2 years. However, the destruction of the wild hosts must be of direct benefit, since it removes a source of infection. Indirectly it has already assisted materially in the eradication campaign. With the majority of the seedlings gone in several counties, there is no longer any need to devote much time to them, and this time can now be given to commercial-orchard inspection, making it possible to cover many more orchards than could be handled formerly.

Although the purpose of the campaign was to control the phony disease, it has brought other benefits. All insects and diseases that attack a crop add materially to the cost of producing that crop, and frequently are the deciding factor between a profit and a loss. The destruction of these wild peach trees, which harbor not only the phony disease but all the other enemies of the peach as well, should aid the growers in controlling all the pests that attack their crop and thus enable them to produce a better quality of fruit at some decrease in cost of operation.

The project received the hearty support of all concerned and is considered to have combined successfully immediate unemployment relief with permanent agricultural and community benefit.

W. F. TURNER, Bureau of Entomology and Plant Quarantine.