. Bulletin. Plant diseases -- United States. SAVING OF FOLIAGE. 81 Tablk <i.—Comparative percentage of cr cent of disease on the trees of all sprayed rows Average i)er cent of disease on the trees of the three rows sprayed in ISiM. but left unsprayed in 1895 ! Those show 3,8 per cent more foliage on the control trees May '.? than April ±2. The percentag^e of foliage of the sprayed trees showino- disease had decreased, however, 5 per cent. Of the total foliage of the trees sprayed in ISiH. ])ut left unsprayed in 1805, 5 per cent more was at the
. Bulletin. Plant diseases -- United States. SAVING OF FOLIAGE. 81 Tablk <i.—Comparative percentage of cr cent of disease on the trees of all sprayed rows Average i)er cent of disease on the trees of the three rows sprayed in ISiM. but left unsprayed in 1895 ! Those show 3,8 per cent more foliage on the control trees May '.? than April ±2. The percentag^e of foliage of the sprayed trees showino- disease had decreased, however, 5 per cent. Of the total foliage of the trees sprayed in ISiH. ])ut left unsprayed in 1805, 5 per cent more was at the second date than at the first. Thesr figures indicate that the divergence in the percentage of on spra3^ed and unsprayed trees was still iiurt^asing just prior to the second estimate. The second estimate may thus be considered as taken before any of the trees had b(>gun to recover from the effects of the disease. The time of maximum contrast was the true time to make the estimates, and it is believed tlu' date of this second estimate was certainly not too late to fully comply witii this rec^uirement. This belief was suhstantiated by a third ptirtial estimate made a week later, which gave in general very simihir results to those obtained May 9. It should also be said that the decrease in the percentage of disease on the sprayed trees between the dates of the first and second estimates did not indicate that the second estimate was made too late, or after the trees had begun to recover, but merely that th(» leaf buds had not fully pushed at the time of the first estimate. This is further shown by the fact that the percentage of disease was still increasing on unsprayed trees up to that time. Before considering the action of individual sprays in saving the foliage from curl, the following comparisons are given of the action of the classes of sprays used: Table 7.—Percentage of healihy foliage on trees differently sprayed. 60^ i I'ercentagcs of healthy foliage sho
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