342 WKEDS OF AGllICUI/rURE. 



well cultivated, where useful crops of corn are obtainedo 

 This dispute is scarcely worth maintaining ; but I believe 

 ihat weeds do much more harm by excluding the light, and 

 so choking the corn, tlian by the nourishment they absorb. 

 This may be allowed to be demonstrated in the case of young 

 quick hedges. These plants strike downwards, and bring 

 their sustenance very much from below the soil; yet if weeds 

 be suffered to overgrow them annually, they are much in- 

 jured, and stinted in their growth. In the early part of the 

 growth of corn, let us consider how essential are the func- 

 tions of the leaves; and for some time after the corn shoots 

 up, the side leaves ought to feel the full effects of light and 

 air; but if weeds interfere, and fill all the intervals that 

 should be, and press upon the crop (growing faster, as some 

 of them do), the crop is deprived not only of nourishment 

 at the root, but of the healthy communication of atmo- 

 spherical influences with the soil and the plants. It is na 

 answer to say, that the weeds thrive notwithstanding ; we are 

 speaking of comparatively tender and valuable plants, which 

 are the objects of necessary and expensive cultivation. 



But by whatsoever means the weeds effect the mischief 

 complained of, it is equally necessary to destroy them. 

 Mr. Pitt, in making a few observations on the corn-poppy^ 

 observes, that " abundance of it is a pretty sure indication 

 of a light crop." Upon which he raises this query : *• Is 

 the lightness of the crop occasioned by the abundance of 

 this plant, or the increase of this plant encouraged by the 

 lightness of the crop ? " To which profound doubt he gives 

 a very careful and ingenious answer : " Probably both.'^ 

 He forgets, however, the rule with which he sets out, "that 

 where weeds cover the surface there can be no room for 

 corn." But the truth of this matter is, that he takes no 

 notice of soil, nor makes any allusion to the efi'ects of season. 

 Weeds peculiar to gravelly and dry soil, as corn-poppy, 

 blue-bottles, may-weed, and corn-marigold (among the list 

 of rampant weeds), as well as corn-bindweed, &c. among 

 fallow-weeds — feel no effect I'lom drought. The hottest 

 seasons are congenial to them ; but the crops of wheat or 

 barley, and sometimes peas likewise, are burnt up at the 



