ADDENDA. 



No. I. 



OF THE VARIOUS ACCIDENTS TO WHICH CROPS OF GRAIN 

 ARE LIABLE. 



HOWEVER interesting it may be, to discuss the accidents to which 

 our crops are liable, yet, in a condensed work like the present, only a 

 general view of them can be given. They may be briefly explained 

 in the following order : Heavy Rains, Fogs or Mists, Dew, 

 Frost, Hail, Snow, Violent Heat, Lightning, Calms, Vari- 

 able Weather, Blights, Birds, and Quadrupeds ; nor ought the mi- 

 nute, but voracious Weevil to be omitted. 



1. Rain. Heavy and long-continued rains are injurious to grain 

 crops in every stage of their growth. Such rains, sour and chill the 

 ground, keep the roots of plants so wet, as to retard their growth, and 

 to lodge the crop when it approaches maturity, thereby depriving the 

 ears of the grain, of a due supply of air, and overcharging the vessels 

 with moisture, while in harvest, they render it difficult to reap and 

 secure the produce. And if much rain happens to fall when any spe- 

 cies of crop, (and especially wheat), is in flower, it not only retards 

 the process of fructification, but, by washing away the pollen or 

 farina fecundans, prevents the proper sexual connexion, without 



which perfect grain cannot be formed. 



2. Fogs or Mists. The diseases, or defective qualities of grain, 

 and particularly of wheat, are sometimes occasioned by a course of 

 thick gloomy weather, especially if it happens when the plants have 

 come to full size, and are ripening their seeds. For though wheat 

 grows in a great extent of latitude, it requires much sunshine to bring 

 it to maturity, and to form the grain of proper quality. 



3. Dews. The ordinary dews are highly propitious to the growth 

 of all sorts of plants ; but when, from a slight degree of frost, or any 

 other cause, the dew is rendered clammy and glutinous, as sometimes 

 happens in this variable climate, it rests too long on the foliage of the 

 plants, shuts up their pores, intercepts perspiration, retards the' 

 circulation of the nutritious fluids, and impairs the health and growth 

 of the grain. What is called honey dew, (suffusio mellita) % does not 

 proceed however, from atmospherical influence, but arises from some 

 interruption of the circulation, in the vegetable fluids of the particular 

 plants on which it appears *. 



4. Frost. The young plants of wheat, are sometimes injured by 

 very severe frosts in winter, and still more, by alternate frosts and 



* Dorset Report, p. 209. Dew-drops have frequently been shaken off the 

 ears of grain, by means of ropes, and other contrivances, and if done before the 

 sun rises, with success. About Bakewell in Derbyshire, it was formerly the 

 practice, for two men, walking in the furrows, to dash the dew off the ears of 

 wheat, to prevent the effects of the mildew. Derbyshire Rejwrt, vol. ii. p. 521. 



