30 PEACH YELLOWS. 



(2) August 10, 1888. Variety, Old Mixon. One limb was removed; two limbs 

 were left. The excised limb bore sound green peaches on nearly all parts ; but there 

 were premature peaches on one small branch. Foliage, excellent; no diseased 

 sprouts; stump, sound. The limbs which were left bore green peaches and beauti- 

 ful foliage. 



RESULT. May 13, 1889. Apparently healthy. 



September 18, 1889. Still diseased, but the symptoms are slight. No fruit this 

 year. 



October 10, 1890. Plainly diseased in all parts. The spring foliage is reddish. 

 Some weeks ago many terminal buds pushed on branches in the top of the tree, and 

 each now bears a whorl of pale green, spindling leaves, 2 to 3 inches long. On 

 many of these branches the lower buds have also germinated, but more recently. 

 The same symptoms occur on a dozen shoots which have grown from the base of the 

 main limbs. No fruit this year. 



(3) August 11, 1888. Variety, Old Mixon. One limb was removed; one was left. 

 The excised limb branched into two equal forks 16 inches above the cut. The stump 

 was sound and the foliage on both forks was full-grown, green, and healthy. All of 

 the fruit on one fork was green and healthy. Most of that on the other was also 

 green and healthy, but two small branches bore ripe, red-spotted fruit, and also two 

 diseased shoots each only about one-fourth inch long. The remaining limb bore 

 green peaches and perfectly healthy foliage. There was not the least sign of yel- 

 lows. 



May 13, 1889. Doubtful. Vegetation is not far enough advanced to tell positively. 



September 18, 1889. Excision apparently entirely successful. No symptoms of 

 yrllov/s. There are no diseased sprouts or germinating buds. The foliage also is 

 thrifty and of the proper form and color. Half a dozen vigorous shoots have grown 

 from the base of the remaining limb. These are 2 to 3 feet long, and bear excellent 

 foliage. No fruit this year. 



October 10, 1890. The tree is now diseased, but the symptoms are confined to one 

 shoot. This grew in the summer of 1890 upon the base of the main limb. It is ro- 

 bust, unbranched, and 2 feet long. The terminal bud developed some time ago, has 

 grown 2-J inches, and now bears a whorl of immature leaves. Below, on the same 

 shoot, a dozen buds have germinated recently and sent out leaves which are one- 

 fourth to three-fourths inch long. 



Otherwise the tree looks as well as its healthy fellows, and but for this one shoot I 

 should certainly think it sound. 



Apparently the disease was not removed by the excision, but has hung about the 

 tree, or been dormant in it, ever since 1888. * 



(4) August 10, 1888. Variety, Old Mixon. Two limbs were removed, both from 

 one side. On one of these limbs was a small branch bearing 8 or 10 premature peaches, 

 on the other were two small branches each bearing IX) to 12 premature peaches. The 

 remainder of the peaches on both limbs, 200 or more, were green and healthy. The 

 spring foliage was abundant, full-grown, and healthy. A few small diseased shoots, 

 one-half inch long, were pushing from the base of a small limb 3 feet above the cut. 

 There were no other signs of disease and the stump was sound. The foliage upon 



* On September 20, 1889, Mr. J. Frank Wilson, of Still Pond, Maryland, took me to a 

 tree in one of his older orchards, No. 4 of my first report, which then appeared to be 

 perfectly healthy, but which he said had shown unmistakable symptoms of yellows 

 in the fall of 1888, at which time he had cut away all but one small limb. At the 

 date of my visit this limb seemed likely to grow into a new and healthy top. This 

 tree was reexamined October 15, 1890, and found to be so badly diseased in all parts 

 that I was compelled to believe that it had not been free from disease at any time 

 since 1888, although it developed no symptoms in the season of 1889. 



Several cases similar to this one have come under my observation, but usually the 

 period of immunity has been shorter. 



