WSP06362

• File Number: 8210.470
• Description: Pacific Southwest Interagency Committee
• State: CO
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 11/1/1971
• Author: PSIAC
• Title: Pacific Southwest Analytical Summary Report on Water and Land Resources based on Framework Studies of Four Regions - November 1971
• Water Supply Pro - Doc Type: Report/Study

002702

without deteriorating the vegetal base and the
ecosystem upon which it is dependent.
Overuse by domestic stock and wildlife has
changed the plant communities to lower yielding, less
desirable and sometimes poisonous vegetation. The
use of land that is unsuitable for grazing because of
steep slopes or unstable soils has added to this
probiem and has produced erosion that further
impedes forage production. Besides inducing erosion,
overuse reduces the ability of the land to absorb the
moisture that falls on it.
Declining range condition in many areas of both
public and private grazing lands has been aggravated
by the shortage of funds and manpower to implement
grazing management plans and install the physical
range improvements that are needed.
The need for red meat in the Pacific Southwest
area is projected to triple before 2020. Range forage
will make a major contribution toward meeting the
demand. Grazing lands suitable and available for
forage production, however, will decrease from the
current 243.5 million acres to 227 million. This will
occur because of competition for more intensive land
uses demanded by the growing population.
The problem of providing dispersed water supplies
for range livestock is small in terms of water volume.
Unit costs, however, are substantial.

Plan Response - Forage

In response to the need for range forage
production, the framework plan includes
management and treatment measures to:
1. Improve and maintain grazing land condition.
2. Provide increased forage.
3. Produce vegetation to enhance watershed
protection and other values, including those
relating to wildlife.
4. Implement grazing management systems.
Forage production can be increased from 25 to
32 million AUM's despite the reduction in the
acreage of available grazing land.
The range forage program will be accomplished
primarily through intensive livestock management. Of
the known methods to manipulate vegetation,
livestock use is the most easily controlled and can be
effectively applied through grazing systems over
much larger areas than other treatment measures.
Grazing systems that eliminate continued use of
grazing areas and provide the forage plants an
opportunity to periodically regain vigor, replenish
food reserves, set seed and reproduce will require
increased fencing and water development. Grazing
systems must be tailor.made to reach the
management objectives for the specific area, such as
wildlife habitat needs and the effects on other uses of
the land.

Land Management

Where the composition of the forage plants has
deteriorated because of invasion of iess desirable
species following overuse, more drastic measures may
be required. In a few critical cases, good forage and
cover plants will be seeded and fertilized.
In some badly depleted areas, livestock may be
excluded temporarily so that new forage and cover
plants can become established.

Unmet Needs - Forage

In the California Region where competition of
land uses is most intense, grazing lands will not
provide the proportion of meat supplies that they
have in the past. The Great Basin and Upper Colorado
Regions, however, have an unused range potential of
some 2 million AUM's. This could be increased to 3
million at the expense of adverse effects upon wildlife
habitat. Development of this unused resource could
be profitable to the Great Basin and Upper Colorado
Regions and could reduce the need for irrigation.
produced feed in the California Region.

Conclusions - Forage

With respect to forage production it is concluded
that:
1. Measures are included in the base plan to
enhance the production of range forage and to
protect the site productivity through intensive
management of livestock use coupled with
physical rehabilitation where necessary.
2. The installation cost of measures to enhance
production of range forage will be $389 rni11ion
in 2020. Operation and maintenance costs will
range from $10 million in 1980 to $19 million
in 2020.
3. Forage deficiencies can be mitigated by
trade-offs among regions, increased production
through intensive management, and can be
compensated by production of meat by other
means than grazing of rangelands.
4. Continued research is needed to develop new
means of reversing the declining trends in range
condition.

CROP PRODUCTION

Status - Crops

Some of the world's most sophisticated
agricultural operations take place on the 13.3 rni11ion
acres of irrigated land in the Pacific Southwest. In the
best of these enterprises management is intensive and
intelligent, even involving the use of computers in

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