.^3. YORKSHIRE. 373 



of the ROLLER and finer harrows fnould be 

 called in. Not a root fhould be left un- 

 Ipofened, nor a feed unlocked. 



When the feeds near the furface haveburft, 

 another cxpofure (hould be made : not by a 

 fiat -plowing, but by raifing the foil into nar- 

 row ridglets by a half -plowing -, thus increa- 

 fing, perhaps doubly, the quantity of furface. 



As the feeds burft and the remainina: roots 



O 



wither, harrow down the ridglets, and there- 

 by expofe freih vidims to the atniofpherc. 



Reverfe the ridglets, and repeat the har-r 

 rowing. 



If a foil be very foul, either with the roots 

 or the SEEDS of weeds, it is in vain to think of 

 making \x. fufficieiitly clean with lefs than five 

 OR SIX PLOWixGS : feven or eight may, in 

 fome cafes and in fome feafons, be necefiary. 



Spear Thistle. 'Ihis and a numerous 

 tribe of biennial "jjeeds are more injurious to. 

 grafs than to corn ; which however is too fre- 

 quently injured by them. 



The nature of this clafs of plants is to form 

 their root-leaves the/r/? year, and to run up 

 to feed the feccnd. The feed matured, the 

 root dies. 



B b 3 Their 



