844 



HORTICULTUEB 



December 25, 1915 



middle of June. Taking the young wood leaving three 

 or four joints. These can be placed in a gentle bottom 

 heat in a greenhouse or make a hot bed with horse ma- 

 nure, letting it stand a week until the violent heat passes 

 off. By keeping them shaded and moist in either case 

 they will root. They can be potted off when well rooted 

 and given shade until they take hold of the soil. By 

 the grafting method you can get some roots of Clematis 

 legustrifolia, C. paniculata or C. viticella to use for stock 

 to graft on. This grafting can be done anytime from 

 January up to the end of March. The best mode is 

 whip grafting. Make a scion, leaving one eye to the 

 piece, and tie on to the stock. The roots of stock can 

 be potted up during the fall and brought into heat 

 about four or five weeks before they are wanted. These 

 pots can be plunged in sand in a warm propagating 

 frame in a temperature of 65 to 70 degrees. Keep 

 close and moist for four or five weeks when they should 

 be gradually inured to the air. When they become 

 hardened they can be grown on in a cool house. Clematis 

 Jackmani can also be increased by layering or pegging 

 down the vines in the ground during the fall and leav- 

 ing them there until the next fall when tliev can l>e 



removed with roots and planted where desired. Where 

 these layers enter the soil they are better to be cut half 

 through which stops the flow of sap, thereby encouraging 

 the formation of rootp more quickly. 



Poinsettias Wilting 



Editor Horticulture, 



Dear Sir: I would like to get information from your 

 Mr. Farrell as to tlie best method of keeping the blooms 

 of poinsettias from wilting after they are cut from the 

 plant. Yours truly, 



Roanoke, Va. P. F. 



In answer to P. F., I would say that the stems 

 should be placed about half an inch in boiling water 

 just as soon as possible after they are cut. Bring the 

 boiling water into the house where you cut them so you 

 will lose no time in sealing the ends. They should re- 

 main from 30 to 40 seconds in the boiling water in order 

 to seal them well. After the ends are treated they should 

 be placed in water well up the stems. We use a tub. 

 They should remain in the water from 8 to 10 hours. 

 This will put them in good condition for shipping or 

 any other use. We have used this method with success 

 so oan recommend it. 



Next Week: — Compost for Winter; Orchids; Starting Freesias; Sweet Peas; Winter Protection; Placing Seed Order. 



A Substitute for Potassium Cyanide 



A good substitute for potassium cyanide is something 

 that all florists who practice hydrocyanic acid gas fumi- 

 gation would welcome. The present war has caused a 

 scarcity in many products which Germany has always 

 supplied, but there are few tilings that have affected 

 those who pursue the various branches of agriculture 

 more than the scarcity of the potassium fertilizers and 

 chemicals. Potassium cyanide is no exception to the 

 rule. However, a good substitute for potassium cyanide 

 is sodium cyanide. 



At present, sodium cyanide is much cheaper than 

 the potassium cyanide and can be used in the same way 

 for gas fumigation. But, certain prerequisites are neces- 

 sary, if one is to use this substitute. First, only f as 

 much sodium cyanide as potassium cyanide is used. 

 Second, a different grade of sodium cyanide must be 

 used. The same strength sodium cyanide as potassium 

 cyanide used would ruin the plants, for much free 

 hydrochloric acid (H CI) would be given off. 



One of the most common impurities is sodium chlor- 

 ide and its action would result in the freeing of the 

 hydrochloric acid as can be seen by the equation : — 

 H2SO''+2 Na Cl=Na2SO^+2 H CI. We must, then, use 

 a grade of sodium cyanide which is much purer, in pro- 

 portion, than the potassium cyanide. It mu.st be 128% 

 pure. The ordinary potassium cyanide that is used is 

 about 98% pure. Such a grade contains 40% cyanogen. 

 However, a grade of sodium cyanide containing but 

 40% cyanogen would ruin your plants as shown by the 

 preceding formula. We, therefore, use 128% to 130% 

 pure sodium cyanide which contains as much as 52% 

 cyanogen and for this reason only three-quarters as 

 much is needed. Don't buy the ordinary druggists'" 

 sodium cyanide, for they carry only the impure grades. 

 Roessler & Hasslacher Chemical Company, N. Y. can 

 supply the pure grade and doubtless there are other 

 chemical companies from which it can be purchased. 



In using either sodium or potassium cyanide for gas 



fumigation, use in lump fonn only. This will offer 

 some resistance to decomposition by the acid and so will 

 give a slower and better distribution of the gas and, 

 most important, will give you more time to leave the 

 house. Cloth bags for holding the chemical are needless. 

 Using lumps one-half the size of an egg, the operation 

 is quite simplified. The acid is poured in the pans, 

 beforehand, and when everything is ready you simply 

 pass through the house and drop the cyanide into each 

 container. Do not use glass containers as much heat 

 is generated and it is liable to break a glass dish. Use 

 earthen ware or granite containers. 



The proportions of cliemicals and the directions are 

 as follows : Two parts (fluid measure) of water are 

 placed in the container and into this is carefully poured 

 and stirred one and one-half parts (fluid measure) of 

 sulfuric acid 98% pure. When everything is ready, 

 drop in one part by weight of cyanide. 



The amounts of cyanide to use in a house vary with 

 the plants, the insects and the cubic feet of space. For 

 white fly on tender plants, you may use .075 grams 

 cyanide per cubic foot of space, while for hardier plants 

 you may use stronger doses. Always remember, how- 

 ever, that you use only three-quarters as much sodium 

 cyanide as you use potassium cyanide. By calculating 

 the amount of cubic feet of space and multiplying by 

 the strength to be used you get the total quantity of 

 cyanide necessary for the house in grams. To get the 

 equivalent in ounces divide by 28.35. 



Always exercise the greatest care in using this fumi- 

 gant as it is a deadlj' poisonous gas. Always air the 

 house out thoroughly for at least one-half an hour be- 

 fore entering after you have fumigated. 



If you are in doubt as to how much you should use, 

 try a weak dose first and, if this does not accomplish 

 results, try a stronger dose next time. Always be careful 

 of using the stronger doses until you know your plants 

 will stand it. 



Amherst, Mass. 



M. S, WUcLrvv 



