I 



APHIDES. 



autumn, and thus the evil will gradually spread 

 throughout an extensive orchard. The nume- 

 rous punctures of these lice produce on the ; 

 tender shoots a cellular appearance, and wher- i 

 ever a colony of them is established, warts or ] 

 excrescences arise on the bark ; the limbs thus 

 attacked become sickly, the leaves turn yellow 

 and drop off; and, as the infection spreads 

 from limb to limb, the whole tree becomes 

 diseased, and eventually perishes. In Glou- 

 cestershire, England, so many apple-trees were 

 destroyed by these lice in the year 1810, that 

 it was feared the making of cider must be 

 abandoned. In the north of England the apple- 

 trees are greatly injured, and some annually 

 destroyed by them; and in the year 1826 they 

 abounded there in such incredible luxuriance, 

 that many trees seemed, at a short distance, as 

 if they had been whitewashed. 



" Mr. Knapp thinks that remedies can prove 

 efficacious in removing this evil only upon a 

 small scale, and that when the injury has 

 existed for some time, and extended its intlu- 

 ence over the parts of a large tree, it will take 

 its course, and the tree will die. He says that 

 he has removed this blight from young trees, 

 and from recently attacked places in those 

 more advanced, by painting over every node 

 or infected part of the tree with a composition 

 consisting of three ounces of melted resin, 

 mixed with the same quantity of fish oil, which 

 is to be put on while warm with a painter's 

 brush. Sir Joseph Banks succeeded in extir- 

 pating the insects from his own trees by re- 

 moving all the old and rugged bark, and scrub- 

 bing the trunk and branches with a hard brush. 

 The application of the spirits of tar, of spirits 

 of turpentine, of oil, urine, and of soft soap, 

 has been recommended. Mr. Duel found that 

 oil sufficed to drive the insects from the trunks 

 and branches, but that it could not be applied 

 to the roots, where, he stated, numbers of the 

 insects harboured. The following treatment, 

 I am inclined to think, will prove as success- 

 ful as any which has heretofore been recom- 

 mended. Scrape off all the rough bark of the 

 infected trees, and make them perfectly clean 

 and smooth early in the spring ; then rub the 

 trunk and limbs with a stiff brush wet with a 

 solution of potash, as hereafter recommended 

 for the destruction of bark-lice ; after which 

 remove the sods and earth around the bottom 

 of the trunk, and with the scraper, brush, and 

 alkaline liquor cleanse that part as far as the 

 roots can conveniently be uncovered. The 

 earth and sods should immediately be carried 

 away, fresh loam should be placed around the 

 roots, and all cracks and wounds should be 

 filled with grafting cement of clay or mortar. 

 Small limbs and extremities of branches, if 

 infected, and beyond reach of the applications, 

 should be cut off and burned." 



Dr. Harris found in Massachusetts several 

 other species of Eriosoma or downy lice, in- 

 habiting various forest and ornamental trees, 

 some of which he thinks may have been in- 

 troduced from abroad. 



Remedies. With regard to the best means 

 of destroying plant-lice, Dr. Harris recom- 

 mends as follows : " Solutions of soap, or a 

 14 



APHIDES. 



mixture of soap-suds and tobacco water, used 

 warm, and applied with a watering pot or with 

 a garden engine, may be employed for the de- 

 struction of these insects. It is said that hot 

 water may also be employed for the same pur- 

 pose with safety and success. The water, 

 tobacco-tea, or suds, should be thrown upon 

 the plants with considerable force, and if they 

 are of the cabbage or lettuce kind, or other 

 plants whose leaves are to be used as food, 

 they should subsequently be drenched tho- 

 roughly with pure water. Lice on the extre- 

 mities of branches may be killed by bending 

 over the branches and holding them for seve- 

 ral minutes in warm and strong soap-suds. 

 Lice multiply much faster, and are more inju- 

 rious to plants, in a dry than in a wet atmo- 

 sphere; hence in green houses, attention should 

 be paid to keep the air sufficiently moist ; and 

 the lice are readily killed by fumigations with 

 tobacco or with sulphur. To destroy subter- 

 ranean lice on the roots of plants, I have found 

 that watering with salt water was useful, if 

 the plants were hardy ; but tender herbaceous 

 plants cannot be treated in this way, but may 

 sometimes be revived, when suffering from 

 these hidden foes, by free and frequent water- 

 ing with soap-suds." 



A solution of whale oil soap, in the propor- 

 tion of two pounds of soap to fifteen gallons 

 of water, is recommended as the best known 

 means of destroying plant-lice, and other in- 

 sects injurious to plants, flowers, and fruits. 

 It was first made known by Mr. Haggerston, 

 of Boston, who designed it originally for the 

 destruction of the rose-slug, and received a pre- 

 mium of $125 from the Massachusetts Horticul- 

 tural Society for his discovery. In preparing 

 the solution of soap, the weight required for use 

 is to be taken and dissolved in boiling water 

 in the proportion of a pound to a quart. Strain 

 this strong solution through a fine wire or hair 

 sieve, which takes out the dirt, and prevents 

 its stopping the valves of the engine, or rose 

 of the syringe. Then add cold water to bring 

 it to the proper strength, namely, about two 

 pounds of the soap to fifteen gallons of water, 

 and apply to the rose bush, or other plant, with 

 a hand engine or a syringe, using as much 

 force as practicable, saturating every part of 

 the foliage. What falls on the ground will not 

 be lost, but do much good in destroying worms 

 and enriching the soil. From its trilling cost, 

 it can be used with profusion, a hogshead of 

 136 gallons costing only about 45 cents. The 

 soap sells for about 6 or 7 cents per pound. 

 Early in the morning, or in the evening, is 

 the proper time for making the application. 

 Among other insects mentioned by Mr. Hag- 

 gerston as destroyed by the solution of whale 

 oil soap, are the Aphis, or plant-louse, which 

 goes by the name of the brown fly; an insect 

 not quick in motion, very abundant on, and 

 destructive to, the young shoots of the rose, 

 peach trees, and many other plants ; and the 

 black fly, a very troublesome and destructive 

 insect, that infests the young shoots of the 

 cherry and the snowball tree. " I have never," 

 he says, "known any positive cure for this 

 insect until this time." 



105 



