CERTAIN INSECT AND FUNGOUS PESTS. 



413 



" The strawberry-blight is met with upon wild vines of 

 both our common species. The gooseberry-mildew is 

 found upon several species of wild gooseberries. The 

 anthracnose, which causes the premature dropping of 

 foliage, is common to several species of currant. The 

 blackberry-rust is an especially important illustration of 

 the relationship of wild plants to those, close of kin, 

 that are cultivated in the garden. This conspicuous rust 

 grows upon the low blackberry, dwarf raspberry, thim- 

 bleberry, wild red raspberry, high blackberry, and sand- 

 blackberry. Diseases of the grape, particularly the 

 mildew, are common to all wild species of the vine. The 

 Virginia creeper and Boston ivy are also victims. 



" Plum-pockets appear as peculiar distortions of the 

 fruit and stems of the cultivated plum, dwarf cherry, 

 bird-cherry, choke-cherry, and some other species of the 

 genus prunus. The peach-curl infests the dwarf almond, 

 common garden plum, three kinds of cherries, and the 

 peach. There is a rust, Pitccinia pi-iini, Pers., which 

 is very destructive in some parts of the country, particu- 

 larly to the peach and apricot in California. No less 

 than ten species of prunus are subject to it, and the list 

 includes the peach, apricot, plum and cherry, several of 

 the last two species being wild trees or shrubs. The 

 black-knot attacks eight species of prunus. 



" It has been fully shown that bitter-rot or ripe-rot of 

 the apple-fruit is the same fungus that causes one of the 

 dreaded decays of grapes ; also that one of the worst 

 enemies of the sweet-potato is identical with a serious 

 disease of egg-plants. There seems little in common be- 

 tween the sweet-potato and the egg-plant, and yet in the 

 face of a common enemy it may be helpful to suggest the 

 importance of not following one crop by the other in lo- 

 calities where both are grown prominently and one or 

 both are already diseased. A bacterial disease of the po- 

 tato also affects the tomato, and vice versa, as might be 

 expected since both hosts are closely related ; but that 

 one disastrous form of melon-blight is due to the same 

 cause is unexpected, because of the lack of kinship be- 

 tween melons and potatoes 



" The apple-rust that yellows the foliage of the orchard 

 in July shortens the crop at picking-time. In a second 

 and very different form it infests cedar trees, there form- 

 ing knots or galls that become conspicuous as gelatinous 

 balls during the spring rains. These orange-colored 

 balls furnish the spores, which falling upon the foliage 

 and fruit of the apple tree, produce the fatal rust. 

 Later in the season the spores from the apple-fungus are 

 carried by the wind to cedars, and a new crop of galls is 

 grown for next spring's campaign against the orchard. 

 Destroy all cedar trees that are anywhere near the apple 

 orchard. 



' ' The evil influence of wild plants may act at long range. 

 It is not necessary that their roots and those of cultivated 

 plants should cross each other in the soil or that their 

 branches should interlock and overshadow one another. 

 Crowding of plants is bad, rank growth of weeds is 

 worse, but the most fatal of all influences is that unseen 

 group of fungi that steals away the health of plants 



which lack nothing for room and enjoy high and 

 thorough culture. 



" Proper seeding, fertilizing and weeding will do much 

 to assist in warding off from healthy plants the deleteri- 

 ous influences of fungous enemies. Let everything 

 possible be done before using the fungicide and then it 

 will have great effect and yield best returns. If so much 

 of the smut, rust, mildew, 

 mold, rot and blight of our 

 cultivated plants is propa- 

 gated by the wild plants 

 hard by, it may be wise for 

 every crop-grower to pay 

 attention to what is thriv- 

 ing outside his garden wall. 

 He cannot build it high 

 nough to shut out the 

 spores, but he 

 can do much 

 to diminish the 

 number of 

 those spores. 

 Having done 

 this, he can 

 take up the 

 spraying-pump 

 with a brighter 

 hope of future success." 



NOTES ON PEACH-DISE.^lSES. 



The subject of peach- 

 yellows has been often and 

 exhausti\'ely treated in this 

 magazine (see Vol. XL, 

 pages 366, 379 and 397, and 

 Vol. XII., page 20), but 

 there is one phase of the 

 disease that we think has 

 not been sufficiently ex- 

 plained. Many peach - 

 growers, especially in New 

 Jersey, declare positively 

 that the disease on their 

 grounds, supposed by them 

 to be the true yellows, 

 yields to liberal applica- 

 tions of potash salts. We 

 do not doubt this, as a 

 number of instances have 

 come under our own obser- 

 vation. Early in July, 1888, we gave to a peach tree, 

 then three or four years old, and showing every symp- 

 tom of the yellows in a fully developed stage, a dress- 

 ing of one quart of muriate of potash scattered over 

 the ground around the trunk in a circle of three or four 

 feet. The tree, then apparently dying, made a new 

 healthy growth the same season and gave a heavy yield 

 of excellent fruit last year. This is a prominent instance, 

 but not the only one that came under our notice. 



Peach Shoot Slightly Diseased 

 WITH Rosette. 



