. Annual report of the New York State College of Agriculture at Cornell University and the Agricultural Experiment Station. New York State College of Agriculture; Cornell University. Agricultural Experiment Station; Agriculture -- New York (State). Fire Blicuit or Pilars, Apples, Quinces, Etc. 159 cispccially favorable conditions the parasite may also live over in blighted shoots or twigs. With the rise of sap and the increased temperature of spring the bacteria in these hold-over cankers become active, multiply and spread into the adjoining healthy bark. Here they increase to such an extent t
. Annual report of the New York State College of Agriculture at Cornell University and the Agricultural Experiment Station. New York State College of Agriculture; Cornell University. Agricultural Experiment Station; Agriculture -- New York (State). Fire Blicuit or Pilars, Apples, Quinces, Etc. 159 cispccially favorable conditions the parasite may also live over in blighted shoots or twigs. With the rise of sap and the increased temperature of spring the bacteria in these hold-over cankers become active, multiply and spread into the adjoining healthy bark. Here they increase to such an extent that on warm, rainy days they ooze from the lenticels and cracks in the diseased bark as thick syrupy drops of a dirty white or brown color (Fig. 16). This oozing from hold-over cankers usually takes place first, about the time the blossoms are opening. Wasps and flies visit these cankers to sip the sweet ooze, and becoming smeared with it from head to toe (Fig. 13) fly away to the opening blossoms. Here of the bacteria of which the ooze is composed are left behind in the nectar of the flower. They multiply rapidly in the sweet solution and the next bee visitor unwittingly carries the fatal germs to all the succeeding blossoms that are visited. The bacteria pene- trate the tender tissues of the flower and within nine or ten days blossom clusters here and there over the trees begin to turn black and wither, fol- lowed shortly by the wilting and black- ening of the leaves on the spur. Blos- som Blight (Fig. 6) is the result. During rainy weather the bacteria ooze from these blighted blossoms and are carried by plant lice, leaf hoppers and Fig. 1$.—Blighted stub resulting ]rom other sucking insects to the tips of introduction of bacteria on the prun- , . 'ng saw. the twigs that are now growmg rap- idly; here, in sucking the sap the insect introduces the bacteria into the tender tissues where Ihey multiply rapidly, producing in a few days the characteristic ''Twig Blight&quo
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