Show SPRAY IS NECESSARY many troubles which contest fruit growers success no other insect has caused so much legislation as san joso scale spread rapidly in east despite precautions by J G saddens SAN DEnS past and gone are those days when large crops of perfect fruit uninjured by curcillo cur cullo codling moth or scab could be harvested without thought of sprays and spray pumps of lead arsenate or parts green of allme sulfur and bordeaux mixture and of other treatments for the troubles which contest the modern fruit growers success in the early days young orchards required but little care after planting other than occasional cultivation until in due time the perfect unblemished fruit was gathered A gradual change has taken place with the in tro and of new insect pests and plant diseases until now spray apparatus and materials are absolutely necessary these changing conditions have taught us a strong lesson of the pos of even more disastrous introductions duct ions of pests there are still many dead white birch trees these were killed on the campus of the university of wisconsin by the bronze birch borer f serious pests in foreign lands which have not become established in our country but doubtless will be sooner or later it systems of rigid inspection of imported plant material are not soon inaugurated the awakening of the entomologists and the public in general to the dan ger of introducing serious insect pests and fungus diseases was caused more largely by the introduction of ate san jose scale than any other one factor no other insect has caused so much state and national legislation as the san jose scale a harmless insect in its native country in central china which infests a wide range of fruit trees as well as many ornamentals ornament als the damage caused by this tiny in sect was early recognized by ento and means were sought to prevent its spread dut before adequate means of control were discovered it bad gained a toot hold in many sections of some of our eastern states and in spite of all precautions has gradually spread what is true of fruit trees Is also true of shade trees take for instance the injury to our beautiful birch trees by insects such a general destruction of birch trees in ornamental plantings has occurred in the past four or five years throughout some sections that the attention of a great many people has been attracted to the loss the small white larva of the bronze birch borer burrows just beneath the bark eating its way irregularly around the trunk and limbs of the tree in the sap bearing layers leaving winding galleries of castings and cutting off the flow of sap beyond the point at work of brown birch borers 1 infested limb showing raised ridges 2 bark removed to show galleries of boring larvae 3 larva hibernating in a cell bored in the solid wood tacked on the younger branches these winding galleries are revealed by the corresponding ridges on the exterior of the limb no adequate remedy has been found to combat this pest it Is always ad elsable to cut out and burn all infested limbs very early each year before the adults emerge until this serious infestation passes over it Is not advisable to plant any birches for loss of the tree Is almost sure to result |