The journal of the Ministry of Agriculture. . Fig. 4.—Black Kuot ul: Plums. The early stage (left) is light-brown,Ihe later perithecial stage is black and FlGr. 5.—Fire Blight in Apple. Commencement of attack. The leaves dieand turn black, and the branch may die back several feet. 1921.] Protection Against Fungi from Abroad. 659 of which there are two or three wild kinds, are also often dis-torted and injured by the black galls. The knots occur sometimes at the end of twigs but moreoften on the smaller branches, where they grow most frequentlyalong the branch in a slow spiral. O
The journal of the Ministry of Agriculture. . Fig. 4.—Black Kuot ul: Plums. The early stage (left) is light-brown,Ihe later perithecial stage is black and FlGr. 5.—Fire Blight in Apple. Commencement of attack. The leaves dieand turn black, and the branch may die back several feet. 1921.] Protection Against Fungi from Abroad. 659 of which there are two or three wild kinds, are also often dis-torted and injured by the black galls. The knots occur sometimes at the end of twigs but moreoften on the smaller branches, where they grow most frequentlyalong the branch in a slow spiral. Occasionally they entirelyencircle the bough, forming a complete girdle, and the boughsoon dies. These black galls so check the nourishment of the branch onwhich they occur that the branch usually dies within a couple ofyears. The lumps or excrescences are light yellow-brown in thespring and early summer, turning black and charcoal-like inthe autumn. The fungus produces spores of two kinds, a summer(conidial) spore from the light brown mass and a different winter(perithecial) spore from the knotty, black autumn stage. These four diseases are of outstanding dange
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectagriculture, bookyear
