Glossary - Afforestation, Reforestation and Forest Restoration in Arid and Semi-arid Tropics - page 249

at least once. Back bearings are measured to cross check the correctness of the survey
operation.

Baffle An obstruction to deflect, check, or break flow or force of water. In a ditch
fence, for example, the ditch is provided with baffles to prevent rainwater from
rushing over long stretches and thereby gathering velocity high enough to cause
erosion, especially where the slope in the bottom of the ditch is steep.

Barbed-wire fence A fence made of barbed wire fixed in parallel lines on posts
fixed in ground.

Bare root plants Plants not transplanted with ball of soil around the roots (and
probably not raised in containers). Such plants are uprooted from the ground where
they grow, and are then planted with roots naked, i.e. cleared of earth. Only certain
species can tolerate naked root handling in arid climate.

Basic schedule of rates A schedule laying down average rates (costs) of different
items of work. It is possible to invert the costs and lay down the average rates of
work output per unit cost or effort, i.e. man-day. A BSR often also includes basic
rates of materials and services.

Beating up Replacing those plants that soon die after the outplanting operation,
in order to avoid gaps in the plantation. This operation is a part of the planting
operation itself and should be considered separate from replacement of casualties
which is carried out in the same season of the next year.

Bed A plot of ground prepared for growing or stocking plants. A container bed is a
strip of dug-up ground meant for retaining plant containers in erect vertical position.
It is also called a stand-out bed. It is called a polypot bed if the predominant type of
containers used are polypots. For brevity, it may also be called a polybed. A sunken
bed is one that has its bottom level below the ground level. A raised bed has its bottom
level higher than the ground level. A germination bed is a specially prepared raised
bed of 10-15 cm height made up of fertile soil meant for sowing of fine seeds. It is
also called a seedbed. The plantlets after germination in a seedbed are pricked out
and transplanted. A mother bed is a large ground or a plot of land for growing plants
to a larger size, usually of 1 year or more. It is also called a growing bed, or a field.

Bench terraces Terraces prepared by cut-and-fill method on steep slopes in order
to prevent soil erosion and to improve moisture retention. Bench terraces are pre-
pared along contours (and are also known as contour terraces). The terraces can be
made level, or provided with a small reverse slope. In areas with better rainfall, a
longitudinal grade may also be provided.

Benzene hexachloride One of the several stereoisomeric chlorine derivatives
(C 6 H 6 Cl 6 ) of cyclohexane, commonly used as pesticides, usually in form of a
dustable powder. A gamma isomer of BHC, known as lindane, is another popular
pesticide.
BHC

⇒ Benzene hexachloride