6 HORTICULTURIST'S RULE-BOOK. 



Little used except when forming a saturated solution, to 

 which may be added about 1 % of sulphuric acid. This is 

 a standard remedy against grape anthracnose in Europe, 

 in winter. 



Corrosive sublimate wash. Dissolve 1 ounce corrosive sub- 

 limate in 1 pint alcohol, stir in 10 gallons soft soap, and 

 add water to make a stiff paint. Apply to base of trees 

 with brush for borers and woolly root-louse. Recom- 

 mended by N. Carolina Experiment Station. 



Fumigation. Fumigating or "Smoking" or "Smudging" 

 in greenhouses is performed by the slow burning of tobacco 

 stems. Best results are obtained when a sheet-iron vessel 

 made for the purpose is used, having holes in the bottom to 

 supply draft. A quart of live coals is placed in the bottom 

 of the vessel, and about a pailful of tobacco stems is laid 

 on them. The stems should not blaze, but burn with a 

 slow smudge. If they are slightly damp, better results are 

 obtained. Some plants are injured by a very heavy smoke, 

 and in order to avoid this injury, and also to more effectually 

 destroy the insects, it is better to smoke rather lightly and 

 often. It is always well to smoke on two consecutive days, 

 for the insects which persist through the first treatment, 

 being weak, will be killed by the second. If the plants are 

 wet, the smoke is more likely to scorch them. The smudge 

 often injures flowers, as those of roses and chrysanthe- 

 mums. In order to avoid this injury, the flowers should be 

 covered with paper bags. For aphids (green-fly or plant- 

 lice). See TOBACCO. 



Gas (Hydrocyanic), for scale-insects. 3 oz. water, 1 fl. 

 oz. sulphuric acid. 1 oz. 60 per cent cyanide potassium. 

 Gas arising (very poisonous) is sufficient for covered space 

 of 150 cu. ft. For dormant trees. Expose 1 hour. 



Glue and arsenites wash. Common glue 1 pound, soaked 

 a few hours in cold water and then dissolved in \ gallon of 

 hot water ; add 1 ounce Paris green, stir well, and add hot 

 water till the mixture measures 2 gallons. For preventing 

 the attacks of borers. Recommended in various writings, 



