348 



D AMPING-OFF. 



moist and warm the infection soon spreads to all the 

 cuttings. 



In propagating beds I endeavor to have all soil free 

 from decaying vegetable matter. I have known sandy 

 soils taken from a sweet potato patch to rot all seeds and 

 cuttings put into it. The particles of roots and tubers 

 remaining in the soil were, in my opinion, the cause of 

 the mischief. In such soils in a warm atmosphere, the 

 damping-off fungi will appear in ten days. 



I guard against damping-off by avoiding a higli and 

 moist atmosphere. If the trouble shows itself, I use 

 flour of sulphur put on the soil dry, and then dry out 

 my houses somewhat. 



From Edwin Lonsdale, Pliilndc-lpliia . — Damping-off 

 is the term used when seedlings and cuttings in a young 

 state, roi off. The cause, sometimes, may be from ex- 

 cessive moisture, and, more frequently than the casual 

 observer is aware, is caused through insufficient mois- 

 ture. If either cuttings or seedlings become really dry, 

 so that the soil or sand in which they are growing exhi- 

 bits the unmistakable signs of dryness, look out for 

 damping-off, after the next watering ; for unless very 

 rare judgement is exercised in giving water, disastrous 

 results will surely follow. The summer time is the 

 worst season of the year for damping-ofi, in our opera- 

 tions here. Of course, that depends largely upon the 

 class of plants in hand. But generally speaking, in 

 the summer more watchfulness is necessary, on account 

 of the excessive hot and dry weather which usually 

 prevails at that season of the year. Take mignonette 

 as an example. When in a seedling state this plant is 

 more inclined to damp-off than anything that I can at 

 this time call to mind. Yet I believe the trouble comes 

 more from the lack of moisture than too much of it. 

 As an illustration : when we grew mignonette, a few 

 years ago, for winter flowering, we had to sow the seed 

 in the hot and dry summer season. Owing to its prone- 

 ness to damp-off, water was given with great caution. 

 But the elements taught us that we did not know what 

 we were about, for, on one occasion, the day after the 

 seed was sown, there was a heavy thunderstorm, and 

 where the water leaked through onto the bed, where 

 the seed was sown, the young plants sprung up in great 

 abundance, and they remained stronger and better all 

 through the season than their neighbors. Ever since 

 that time we have kept the seed bed thoroughly moist 

 from the day the seed is sown until the young plants 

 are quite strong. In order that there may be no mis- 

 apprehension in this matter, it perhaps will be necessary 

 to state, that, because the treatment indicated suited the 

 germination of the seed and for a time sustained the 

 young plants, it does not follow that the soil in which 

 plants are growing should be kept in a state of satura- 

 tion all the time. 



There is also a thread-like fungus which attacks cut- 

 tings in propagating beds, and seedlings in seed-pans, but 

 generous supplies of water applied directly on the seed- 

 lings and cuttings will hold it to a great extent in check, 

 and the young plants will be stronger and better than if 



allowed to exist in dry sand or soil and a dry atmos- 

 phere. 



Fro.mB.M. Watson. Jr., Bitssey Insiitiiiion, Jamaica 

 Plain, Mass. — Damping-off is a contagious disease at- 

 tacking plants and cuttings just above or below the sur- 

 face of the soil, resulting in death or serious injury. 

 In my experience the cause is principally a fungus 

 growth which fills the soil, and covers the surface with a 

 mass of thread-like bodies, identified by Professor 

 Farlow of Cambridge as the mycelium of Pytliinvi om- 

 nivoia : in no case have we failed to notice this present 

 in a greater or less degree, but I have reasons for 

 thinking other fungi may be concerned. The growth of this 

 fungus seems to be due to the combination of too much 

 moisture and too high a temperature ; the ravages are 

 more noticeable when plants are grown in a house war- 

 mer than they like. Plants are troubled most when 

 grown under glass, chiefly in February and March, when 

 a variety of seeds are sown, many of them almost un- 

 known to us. It is serious on all germinating seeds, and 

 young seedlings making their first growth ; I have also 

 found it on cuttings in sand, on cinerarias in eight-inch 

 pots, and on red cedars and other hardy plants in a pro- 

 pagating frame. 



Preventives and Remedies. With cuttings, use a fair- 

 ly cool house, avoid confined air, ventilate thorough- 

 ly, and admit as much sunlight as possible without wilt- 

 ing ; Dot off or reset in fresh sand when any symptom 

 appears. By these means we have not been troubled 

 with attacks for several years. When a close atmos- 

 phere is necessary, guard against too much moisture 

 and keep an even temperature. When large plants like 

 cineraria are injured, it means the temperature is too 

 high or too variable, and the remedy is simple. With 

 young seedlings and germinating seeds, the difficulties 

 are greater ; for preventives, use a fresh sandy soil, free 

 from any recently decayed organic matter ; use well 

 drained pots, pans, or boxes ; avoid over watering, par- 

 ticularly in dull weather, shade in the middle of the day 

 only, and keep the temperature as low as the nature of 

 the plants will permit. Do not sow seeds of plants like 

 carnations and pansies in heat. The best remedy is to 

 prick off into fresh soil as soon as any fungus appears ; 

 this can easily be done with the stronger growing kinds. 

 Young plants of which nine-tenths of the root is eaten 

 off can sometimes be- saved. Fine seeded and slow 

 growing varieties are not so easily managed. We scatter 

 on dry sand at first ; for worse cases, we sift on sand so 

 hot that it can hardly be handled ; this will sometimes 

 check the fungus growth or make it possible for the later 

 coming seeds to succeed where the first perished. We 

 are now experimenting in seed sowing in live sphagnum 

 with a little sandy soil added. 



From Professor L. H. Bailey, Cornell Uni'versity. — 

 Damping-off is a term loosely applied to the decay of 

 cuttings or young plants at or near the surface of the 

 ground. The first appearance of the trouble is a brown- 

 ness of the parts. The stem soon becomes constrictetj 

 at the point of attack in many plants, and the plant soon 



