52 



the ignorant tid-ang I'ditn to handle the Sulphuric Acid respect- 

 fully; and as the use of hurnt earth can he avoided in some measure, 

 pecuniary gain is brought into sight). — Ed. 



Damping-off is the term applied to the failure of seedlings due 

 to their infection while in a tender state by certain soil-inhabiting 

 fungi. The reason for the name is the association of the trouble 

 witli conditions of more or less excessive moisture, whicli favours 

 tlie development of the parasite at the same time that it increases 

 or prolongs the tenderness of the plants. Though not necessarily 

 confined to seedlings crowded in boxes or seed-beds, it is amongst 

 such that the affection usually appears and, by progressive infection, 

 is able to cause extensive losses. Merely reducing the density 

 with which tlie seed is sown is often sufficient, by permitting in- 

 creased ventilation, preventing the drawing up of the seedlings, 

 and making the spread of infection more difficult, to avoid or re- 

 duce the damage. 



The longer the soil of the seed-bed has been in use and the 

 more decaying animal or vegetal)le material it contains, the more 

 likely it is to harbour fungi capable of causing damping-off. Heavy 

 water-retaining soils are more favourable to the affection than 

 those whicli are light and porous, and i;rovisiou for rapid drainage 

 is one of the most important precautions against it. Over-shading 

 and close shelter, Ijy maintaining humidity, increase the tendency 

 to it; in these respects, as in the supplying of water, the conditions 

 which favour the seedlings favour the disease, and a mean has to 

 be struck between slow growth and loss. 



The trouble occasioned by damping-off in these islands (AYest 

 Indies) is not so great as might be expected by an agriculturist 

 accustomed to temperate countries, where warm, humid weather, 

 such as is associated with ideas of the tropics, is greatly feared in 

 this connexion. 



In the first place nearly all the staple food plants, sugar- 

 cane, bananas, tannias, dasheens, sweet potatoes, yams, cassava, 

 are raised from cuttings of one sort or another. Cotton, corn and 

 pulses, which are raised from seed, are planted a few seeds together, 

 in their permanent positions in the open ground. Of agricultural 

 as distinct from garden crops tobacco, onions, and limes, which are 

 raised in seed-beds, have been the plants to suffer most in the West 

 Indies from the affection under notice. 



Notes on the subject, embodying;' the results of experiments 

 conducted in tlie United States, were i)ublished in Volume XIII, 

 of this Journal (p. 380). A bulletin recently received {United 

 States Dejinrlnienl of Agriculture Bulletin, No. ^-5-3), by Messrs. 

 Carl Hartiev and l\oy (J. Pierce, states the conclusions derived from 

 further studies, made on coniferous seedlings. 



The authoi's point out tliat the methods of prevention com- 

 monly adopted by nurserymen, such as the use of sandy soil, the 

 use of sand or gravel for surfacing the beds, the provision of 

 o-ood drainai^e and \entilation. M'hile often successful, do not avail 



