The Canadian Horticulturist. 51 



COPPER SULPHATE AGAINST FUNGI. 



EXPERIENCE during the summer of i88g encourages the belief that 

 we have in the solutions of copper sulphate a defence against many 

 of the fungus pests which so seriously threaten the prosperity of our 

 agriculture. In 1888, the efficacy of what is known as the Bordeaux Mix- 

 ture, as a preventive of mildew and Black Rot of the Grape, was fully 

 proved. This year experiments have taken a wider range, and many of 

 the so-called diseases of plants have been successfully treated. The 

 Apple-leaf rust {Rcestelia pyrata) succumbs to an occasional spraying with 

 the Bordeaux Mixture. The Quince blights {Morthiera Mcspili and Hen- 

 dersonia Cydotiice) are likewise prevented, and the fungus, which causes the 

 blight of leaves and cracking of fruit of the Pear, may now be regarded as 

 under the control of the copper solutions. 



The prevention of this Pear fungus, Entomosporiuni maculatum, is, per- 

 haps, of greater advantage in the nursery than in the orchard. Where the 

 disease is epidemic in the nursery it places a veto upon the budding and 

 grafting of young Pear stocks. The leaves are destroyed just when their 

 aid is essential to the vitality of the bud or cion. By spraying the nursery 

 rows every three weeks, during the season of growth, with the Bordeaux 

 Mixture, the leaves are preserved in health and the success of the grafter's 

 labor is assured. 



But, in addition to this use of the copper solution, it is found to be pre- 

 ventive of the Tomato blight {Macrosporium Solani), and (which is of far 

 wider importance to our agriculture) it prevents the Rot of the Potato, 

 FhytophtJiora infestans. In treatment of this disease of the Potato-plant, 

 some of our experiment stations have this year been quite successful. My 

 experiments in this line have had gratifying results. For many years in 

 this region of Southern New Jersey, every attempt to grow the Peachblow 

 Potato has been a failure. At about the time the plant is in blossom, and, 

 the tubers are, say one-fourth grown, this deadly blight invades the Potato 

 field, and sweeps over it like fire. I have had an acre of Peachblows 

 showing every sign of thriftiness, and giving promise of a heavy crop, and, 

 in one week from the time of the appearance of this blight, every plant was 

 dead or dying. It is the prevailing opinion here that the Peachblow 

 Potato is a variety which is " run out," and its culture has been generally 

 abandoned. 



Happening to see, last autumn, a few bushels of small Peachblow 

 Potatoes for sale, I bought them for the purpose of giving them another 

 fair trial under the protection of the Bordeaux Mixture. Last June I 

 plowed a clover sod between the three-rows of an orchard, and there 

 planted these Potatoes in five equal plats of three rows each, manured in 

 the row with the Mapes Potato Manure, at the rate of half a ton per acre. 



