212 TRANSACTIONS OF THE ZLLINOIS 



effect of this grass system in the orchards he has been in. Do they 

 succeed in grass? are they longer lived? and do they bear fruit that 

 is worth having? 



Mr. Meehan — If you travel through Pennsylvania you will be 

 astonished at the great number of pears, apples and cherries which 

 are healthy and bear large amounts of fruit, and you will find that 

 the}' are protected by briars, raspberries, &c. On the other hand, if 

 you will look at the cultivated ground you will scarcely ever see a 

 healthy tree. This wiirshow that these trees are better than when 

 cultivated on the regular garden plan. In the latter case they are 

 almost always affected with leaf-blight — the leaves fall off at the end 

 of August, and then there is no more ripening for the fruit. 



Dr. Hull— Explain the cause of the leaf-blight — this peculiar form 

 of it. I think you mentioned something about it once to me. 



Mr. Meehan — It first makes its appearance about the middle of 

 July. You have to look closely to observe it. You will, by holding 

 the leaf up to the light, see faint yellow patches, and if you place 

 them under a microscope you will see a j^ellow, round fungus. As 

 each fungus develops itself, the tissue in the immediate neighborhood 

 dies, but whether it breeds in the tissue, or whether it is drawn into 

 its system through the roots, or whether the spore attaches to the 

 outside of the leaf, I have not seen any experiments that would prove 

 it to me. There is one thing j^ou can observe in connection with it, 

 and that is, that the weakest fruits and the weakest trees get attacked 

 by it first, and that would seem to show that the tree whose vitality 

 is weakest is more favorable to the progress of the disease than if 

 -.the trees were perfectly healthy. 



Mr. Pierson — In the case of a pear or apple orchard, at what age - 

 in the history of that orchard would you commence the system of 

 mulching, either by grass or artificial mulch? 



Mr. Meehan — That would depend entirely upon the peculiar cir- 

 cumstances of the case. The physician would have to see the patient 

 ^nd that is exactly how I should be situated in judging of the time 

 when I would commence mulching. If the surface of the soil was 



