66 MAINE) AGRicuLTuRAi, e;xpe;rimi;nt station. 191 1. 



of experimental error, and their use in making comparisons 

 between individual plots cannot serve as the basis for warranted 

 conclusions. 



Neither of the home-made sulphur sprays were quite as ef- 

 fective as the commercial concentrates. On the basis of former 

 experiments, some reduction in fungus control was to be ex- 

 pected in the case of the self-boiled lime-sulphur. The con- 

 clusion, however, that home-made lime-sulphur concentrate is 

 inferior to the commercial sprays, must not be drawn from one 

 year's results, especially in view of the many experiments al- 

 ready cited, pointing to the contrary. We believe that this fall- 

 ing off, compared with the commercial solutions, may be partly 

 accounted for by the greater foliage density of the trees of this 

 plot. It is reasonable to suppose that with equal care in appli- 

 cation, such increase of leaves, especially towards the center of 

 the tree, would not only make control of the fungus more diffi- 

 cult, but the greater shade and reduced aeration would render 

 propagation easier. The same explanation, although to lesser 

 degree, may hold for Plots 10 and 11. Plots 9 to 12 inclusive 

 consisted of somewhat larger and denser trees which had not 

 been quite so heavily thinned in the pruning of the preceding 

 winter. In general, however, we may consider this year's data 

 confirm the consensus of results obtained elsewhere as to the 

 practical efficiency of lime-sulphur sprays in the control of apple 

 scab and other fungi. 



Injury to Foliage and Fruit. 



"We have already seen that the lime-sulphur sprays proved 

 immeasurably superior to bordeaux in their effect on foliage, 

 and this under seasonal conditions at spraying time that put all 

 materials used to the most severe test. On the question of in- 

 jury to fruit, caution is needed in drawing conclusions. This 

 is obvious when we consider the per cent of deformed fruit on 

 both unsprayed plots (Table 12) and note its appearance (Fig. 

 55). These amounts run sufficiently close to the per cents 

 indicated for the lime-sulphur sprays to warrant the assumption 

 that the unknown agencies classed as weather conditions were 

 this year responsible for much of the damage on the sprayed 

 trees. Whatever these natural agencies may be, they were this 



