32 TRANSACTIONS OF THE ILLINOIS 



tacked late in the season in which the leaves have performed their natural office, show the dis- 

 ease only in the veined and yellowish appearance of the leaves. The roots ot these trees in the 

 following spring look much as that part of healthy roots would do which had been bared to the 

 light and air, being in color between that of roots and branches, but in this respect resembling 

 most the latter. Even the smallest roots present more or less this appearance; and in the early 

 season are destitute of those small warty excrescences from which new rootlets and spongioles are 

 formed. Hence it seems impossible that the roots should aid the growth of the tree, except by 

 absorption of moisture, as when the trees are in a state of rest. 



The yellows appear to be carried by bees from infected to healthy trees, while the trees are in 

 bloom. In the orchard of the Winters Bros., at Du Quoin, we found several peaches, one side of 

 which was, to all appearance, in a healthy condition, while the affected half ripened several days 

 earlier than the healthy side, the early ripened half also had those peculiar yellowish dots on the 

 surface a:id the reddish stain of flesh that always so conspicuously marks the fruit of diseased 

 trees. The Winters Bros., after many years experience with the yellows, inform us that they are 

 of the opinion that it is highly contagious, the disease being conveyed by pruning trees in health 

 with tools that have been used on infected trees, also, by the plough. To settle this point, I se- 

 lected a vigorous peach tree in my own orchard, of the Oldmlxon variety, and macerated in water 

 some of the specimens taken from one of the De Soto orchards of Missouri. We placed this sub- 

 stance in contact with the alburnum. In about two weeks the leaves nearest the main branches 

 began to show the yellowish veining of the leaves, and a few days later the young and partly 

 grown leaves near the end of the branches also assumed the peculiar yellowish tints characteristic 

 of the disease, the growth of all the branches was arrested; from the base of the leaves on a few 

 of the most succulent shoots a tew new shoots put forth, the leaves of which were soon checked as 

 before described. Were we to leave this tree to grow another year the skin of the fruit would be 

 dotted over with yellowish dots, and the flesh streaked and colored with the peculiar pale logwood 

 red — a characteristic mark of the yellows, and ripen two, three, or even tour weeks earlier than 

 on healthy trees, and by the first of August the tree would be leafless without the power of per- 

 fecting a single healthy leaf. In this condition the tree being destitute of new roots and spongi- 

 oles, is starved for the want of food. 



In view of the facts of which mention has been made, nurserymen should be vigilant, and not 

 select t!:eir seeds from unhealthy trees, nor from districts even where this disease is known to 

 exist. 



The practice now so common of purchasing seeds of the canning establishments also should be 

 abandoned, and districts known to be healthy sought from which to obtain a supply. 



Had we not already given so much space to the peach, we should like to detail in full our im- 

 pressions on visiting orchards trained to low heads. Ours was perhaps the first orchard in the 

 West so trained. We therefore consider that the statements we make on this point are due at our 

 hands. Our early success with low headed trees led several writers to consider the style of the 

 trees as being of much importance, but they forgot to return to the subject when we detailed our 

 reasons for changing the form of our trees. It has also been difficult to impress those about to 

 start orchards that they had any more to do than to plant and reap. And then how easy and nice 

 it would be to gather the crop on one's knees; we so operated for two years, when our devotional 

 feelings left us. Indeed, of all the mischievous recommendations wherewith to cheat the horti- 

 culturist all sink to nothingness when compared with the advice to grow orchards with heads 

 branching from the ground. When we consider the difficulties that attend the culture ot fruit, 

 we doubt if the practice of growing trees with low heads can be successfully defended from any 

 point of view. The labor of catching insects, if not rendered impracticable is increased ten 

 fold. 



The trees are deprived of the under, circulation of air which is so essential to their health in 

 the season of growth. If the ground is to bo thoroughly cultivated the low heads increase the 

 labor many fold. If clean cultivation is neglected, then the weeds quickly grow up in competition 



