118 EXPERIMENTAL FARMS. 



DEDUCTIONS. 



It will be seen that the variety Northern Spy was affected to a very small extent by 

 either rot or scab, so that the weight of evidence is given by Clark's No. 1. It will here 

 be noted that over 90 per cent of the yield of the check (untreated) plots of this variety 

 were affected by scab. 



In this experiment, as in that reported later in connection with treating bean seed, 

 Lysol gave the most decisively satisfactory results. Corrosive sublimate ranks next, with 

 a very small percentage of affected tubers. Formalin gave very unsatisfactory results as 

 compared to lysol and corrosive sublimate. I cannot account for this variance with the 

 results secured by Professor Arthur. It will be noted that there were duplicate plots of 

 the lysol treated seed, and that the results are harmonious throughout. Nitrate of soda 

 and kainit both gave better results than formalin. 



ROSES INJURED BY ABUNDANT GROWTH OF MUCOR. 



Rather an unusual occurrence is described in the following letter, which accompanied 

 a package of rose foliage arriving on 3rd May last : — 



"Montreal, May 3, 1897. 



" Dear Sir, — The inclosed leaves you will find are covered with black dots. 

 Whether it is a fungus or scale insect I should like to know. The leaves are from rose 

 bushes forced under glass in the usual way with florists in this country. The roses are 

 in good condition as to health and vigour, and the fungus, or whatever it is, has appeared 

 only within the last two weeks. About two weeks ago we mulched the rose beds with 

 fresh cow manure obtained from a neighbouring farm. I think it is from this source it 

 came, as it is only since then that it has appeared, and now the whole house is covered 

 with it, even the glass and woodwork. Other plants in the same house are covered with 

 it also. If you can inform me of any means whereby I can cure it and get the house 

 cleaned, I will feel much obliged to you. 



" Yours sincerely, 



"George Kerr, 



" Gardener to C. Campbell" 



I took occasion to visit the houses in question, and found the condition of the plants 

 substantially as described by Mr. Kerr. The fresh cow manure laid over the bushes to 

 the depth of three to four inches had furnished the right conditions for the rapid growth 

 of mucor, a low form of saprophytic fungus. The small black spherical bodies, like little 

 pellets, covering the rose leaves, mostly on the under sides, were the sporangia of 

 the organism. These had been adjuncted with such force as to carry them a distance 

 of four and a half feet from the breeding beds and lodge them on leaves, glass, wood- 

 work or whatever they might strike. The propelling power seemed remarkable. This 

 organism, while not parasitic in character, rendered the flowers and plants unsaleable 

 and caused considerable loss. The fermentive action was promptly arrested by covering 

 the beds with a light coating of air slaked lime — land plaster would probably serve 

 equally well. Under ordinary circumstances the sporangia will begin to be ejected 

 about ten days after the application of the manure to the beds. 



celery leaf spot (Cercospora apii). 



The prevalence of celery leaf spot or rust as it is called by gardeners was the source 

 of much loss this year to the truck growers in the vicinity of large cities, 



" Outremont, August 3. 



" Dear Sir, — Inclosed please find a few celery leaves that I picked from my celery 

 patch. They become rusted and fall off, which prevents, to a large extent, the head from 

 forming. Kindly inform me the cause, and give a remedy to prevent it, as it is a great 



