DRAIN: To remove water from the soil by artificial means, such as drainage ditches, buried perforated plastic pipes, or a gravel sump. Also to improve heavy clay soils with sand or organic matter.
DRAINAGE: 1. The removal of excessive water from the ground. 2. Water moving down in the soil. 3. A system of conduits, channels or passages by means of which something is drained.
DRAIN-WELL: A pit sunk through an impenetrable layer of earth or stone to a porous layer, to draw off water.
DREPANIFORM: Sickle-shaped.
DRIED BLOOD: An organic fertilizer that leaves an acid reaction.
DRIED FLOWERS: Blossoms that have been dehydrated but have retained a natural shape and color.
DRIFT: Soil material deposited by geological process in one place after having been removed from another place.
DRILL: 1. A machine used for planting seeds, as of grasses, wheat, oats, corn, etc. by dropping them in rows and covering them with earth. 2. A row of seeds deposited in the earth; the trench or channel in which the seeds are deposited. 3. To sow seeds in rows (i.e. the field was drilled, not sown broadcast).
DRIP IRRIGATION: A system of watering by which moisture running through a porous hose is slowly released through tiny holes, or emitters, to the root zone of plants.
DROUGHT-TOLERANT PLANTS: Plants that can survive periods of time with little or no water.
DROWNING: A surplus of water that drowns plant roots by eliminating oxygen from the soil.
DRUPACEOUS: Pertaining to or producing drupes.
DRUPE: A stone fruit having a hard, nut-like inner part surrounded by a fleshy or fibrous outer layer (i.e. cherry, peach, olive, walnut); a small fruit with a single seed.
DRUPELET: A small drupe, especially as applied to the individual components of aggregate fruits such as raspberries and blackberries, which consist of numerous seeds, each surrounded by its own fleshy layer. Also drupel.
DRUXY: Pertaining to a tree or timber, having decayed spots or streaks in the heartwood.
DRY SAND: A sandy deposit with low water-holding capacity.