
539. 

_ New Yorx AgricutturaL Exprrment Srarion. 
of the fungus which causes bean anthracnose, a more extended 
account is appended below. 
In conclusion the following treatment for bean anthracnose is 
recommended. 
“1, Selection of sound seed for planting. 
2. Immediate removal of infected seedlings from the field. —* 
3. Keeping the foliage covered with Bordeaux mixture. 
The first recommendation may well be followed out during leisure 
hours between harvest and planting time. It will probably 
accomplish as much as two good sprayings, and we have no doubt 
that time spent in selecting seed is very profitably employed. 
The second recommendation should be carried out thoroughly. 
To pull out the plants and leave them on the ground is not 
sufficient, for on the uprooted plants the fungus will quickly 
ripen its spores and will live long after the plant is dead. 
Many object to the use of Bordeaux mixture because they . 
experience so much trouble in preparing and applying it. Prepara- 
tion of Bordeaux mixture may be simplified by a test which 
obviates the necessity of weighing the lime, and, where large 
‘quantities of lime are used, permits slacking the lime in large 
quantities at one operation. The copper sulphate is weighed and — 
mixed with an amount of water sufficient to dissolve it. When 
___ it is completely dissolved, the lime, in the form of thin whitewash, 
ig strained through burlap (gunny sacking) into the copper sul- 
| phate solution.* A drop or two of potassium ferrocyanide (satu- 
_ rated aqueous solution) added from time to time after thoroughly 
stirring the mixture will show when enough lime has been added 
to form the Bordeaux mixture.§ If not enough lime has been used, 
the drop of ferrocyanide will turn to a very dark color the moment 
it touches the mixture; if enough lime has been used, the ferro- 
cyanide will not change color when it is dropped into the mixture. 
Water is then added till the Bordeaux mixture is diluted to the 
desired strength. The commercial form of potassium ferrocyanide 
may be used for this test. A uBR) for the entire season may be 
i purchased for a few cents. 






} * If care is used in keeping the whitewash free from any substance which would clog the 
“nozzle, straining the mixture may be dispensed with. 
- § This test was first proposed by Dr. G. Patregeon. See Jour. d’Agric, Pratique, 1890 t. ES 
; p- 701, 


