TheImprovement ofTropical and Subtropical Rangelands

324 IMPROVEMENT OF TROPIOAL AND SUBTROPIOAL RANGELANDS
THE BEMA SYSTEM IN SAUDI ARABIA
Ahmia in the TaU area of Saudi Arabia were studied to determine
the boundaries, location, method of upkeep, ownership, grazing
rights, and the presence of old water and soil conservation works. A
total of 30 ahmia were located, and investigation showed that 18 were
well looked after and kept under proper controls, while 12 were open
to unrestricted grazing. The Hema Banu San in the Hijaz mountains
was selected for a special study.
The range has long been protected, and its history can be traced
back some 500 years to the reign of Sharar Husayn of Makkah
(Mecca). Two tribes, Banu Sarr and Banu Hassan, quarreled over its
control, but Sharaf Heidera, a judge of Sharar Husayn's reign, gave
his verdict in favor of Banu Sarr and conferred upon this tribe the
rights of custody and use. The Hema Banu Sarr has been protected
since that time.
This pasture, with total surface area of about 800-1,200 hectares,
is located north of Belgurashi at about 2,000 m above sea level.
Yearly average rainfall is between 400 and 500 mm. Soil profiles
observed along road cuts showed substantial accumulations of good
soil under the grass cover. This soil has retained its fertility and has
the capacity to produce abundant forage.
Increased growth of choice grazing plants has reduced the growth
of undesirable vegetation, and high-productivity grasses now dominate
the landscape. The grass cover is composed mainly of genera
such as Themeda, Aristida, Andropogon, and Stipa. Localized
patches of 01lmbopogon and Pol1lgala were also found, together with
some Olea ehr1l8oph1l11a and Juniperu8 proeera. The plant cover of
the areas outside the hema is composed of heavily grazed grasses
and large numbers of nonpalatable shrubs. Dodonea weo8a, Olea
ehr1l8oph1l11a, and Juniperu8 proeera are also present in fair number.
The right of use of this hema is strictly limited to the Banu San
tribesmen. No year-long grazing is allowed, but cutting of grasses is
permissible during periods of scarcity or late in the summer season
when the grass is mature. Permits for cutting or collecting grass
are granted by the tribal head. No more than a specified number of
persons of each family is allowed to cut mature grass, and then only
on certain days of the week.
Although no reliable data is available on the number of animals
for which this range is kept as a reserve, it is evident that an
equilibrium between vegetation and animals has always been maintained.
The perennial vegetative cover of palatable grasses within