1872 



ENCYCLOPEDIA OF PRACTICAL HORTICULTURE 



For Aiifs and Wasp Nests 

 A small amount of this liquid poured 

 Into underground nests of ants, wasps, 

 etc., will suffice to destroy the inhabitants 

 very quickly. 



Hydrocyanic Acid Gas 

 Hydrocyanic acid gas is generated by 

 the addition ot diluted sulphuric acid to 

 sodium or potassium cyanide. The gener- 

 ation is made in an earthenware jar, the 

 gas being confined in a fumigation house 

 or, if the work is being done in the or- 

 chard, in a tent thrown over the tree. 

 For many years the methods of fumiga- 

 tion depended entirely upon each fumiga- 

 tor, there being no uniform or common 

 procedure. The results o£ this early work 

 so clearly showed the need of systematism 

 that the United States Department of Ag- 

 riculture set experts to work out a re- 

 liable and uniform system of procedure. 

 Dr. A. W. Morrill inaugurated the pres- 

 ent system of marked tents and a sys- 

 tem of dosage, which is known as "The 

 Morrill System." This work was done 

 in Florida. Later Mr. R. S. Woglum be- 

 gan operations in California and greatly 

 perfected this system, so as to make it at 

 once practical and available to all the or- 

 chardists. 



HYDROCYANIC ACID GAS 



Potassium c.vanlde 1 oz. 



Sulphuric acid 1 fluid oz. 



Water 3 fluid ozs. 



Place water and acid in earthenware 

 vessel and add cyanide. To be used un- 

 der tents or tight rooms or boxes. 



For fumigating buildings or nursery 

 stock, one ounce of cyanide to each 100 

 cubic feet for one hour. 



For scale insects on citrus trees, maxi- 

 mum or purple scale dosage found by mul- 

 tiplying distance around by distance over 

 top of tented tree and pointing off two 

 places. Example: 



Distance around Distance over 



40 ft. X 20 ft.^8 ozs. cyanide 



For red or black scale, reduce one- 

 quarter. Example: 

 Distance around Distance over 



40 ft. X 20 ft.=8. — yi:=0 ozs. cyanide 



Fumigation Schedule. See page 1499. 



Tobacco Fnincs 



For very tender house and greenhouse 



plants infested with plant lice, thrips, 

 etc., it is sometimes advisable to fumi- 

 gate them with slowly burning tobacco, 

 but even in such cases iiydrocyanic acid 

 gas is replacing the more uncertain to- 

 bacco fumes. 



HANDS 



To prevent insects from crawling up 

 the trunks of trees and plants various 

 bands have been devised which have 

 proven exceedingly successful in many 

 instances. 



Asphaltum 



A strip (J to 8 inches wide painted about 

 base of tree trunk to prevent the entrance 

 of the peach-tree borer. 



Cotton liiinds 



Bands of loose cotton fastened around 

 the trunks of the trees are excellent in 

 preventing the ascent of insects. 



Mosquito wire netting similarly applied 

 is also in use against the canker worm. 



Oiled Paiier 



Oiled paper tied around the trunks of 

 small vines and plants is an old method 

 which sometimes proves practical today. 



Sticky Rope 



In the work on the California tussock 

 moth, W. H. Volck recommends the use 

 of rope bands saturated in an easily pre- 

 pared mixture as follows: 



Castor oil 1 gal. 



Ucsln Ifi lbs. 



lor any fraction thereof) 



The resin and castor oil are gently 

 heated until the former is completely 

 melted. If too thick more oil may be 

 added. The bands dipped in this mixture 

 should be replaced by new ones about 

 every ten days. 



Crude oil rich in asphaltum or a mix- 

 ture of equal parts of pine tar and 

 molasses have also given satisfactory re- 

 sults. 



Taiiglofoot 



Tree tanglefoot is a thick, sticky sub- 

 stance which, when applied as a band, re- 

 mains moist for several weeks and is a 

 very effective barrier against canker 

 worms, caterpillars, cutworms. Fuller's 

 rose beetle and other crawling insects. 



The material is put up in cans. It 

 should be applied directly to the trunk of 

 the tree several feet above the ground. 



