STRESS FACTOR WHICH MAY BE PARASITIC (WEEDS) OR NON-PARASITIC OF ANIMAL, PLANT OR VIRAL ORIGIN.

NON-INFECTIOUS, NON-PARASITIC STRESS FACTOR THAT CAUSES AN IMBALANCE BETWEEN THE PLANT AND THE ENVIRONMENT IN WHICH IT LIVES.

TYPE OF SOIL CONTAINING AT LEAST 40% CLAY.

VERY FINE-GRAINED, NON-LITHIFIED SEDIMENT (GRAIN SIZE LESS THAN 2 ?M IN DIAMETER ) CHIEFLY COMPOSED OF HYDROUS ALUMINIUM SILICATE MINERALS BELONGING TO THE CLASS OF PHYLLOSILICATES.

WOODY-STEMMED PLANT, USUALLY LACKING A SINGLE TRUNK, BRANCHING FROM OR NEAR THE BASE.

SEE ARARE.

AGRICULTURAL IMPLEMENT USED TO TURN OVER THE SOIL IN PREPARATION FOR SUBSEQUENT CULTIVATION OR SOWING.

TO BREAK AND TURN OVER THE EARTH WITH A PLOUGH.