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MISCELLANEOUS PUBLICATION 1271. U.S. DEPARTMENT OF AGRICULTURE 



1959 indicated that pasturage was generally fair, 

 with the balance sparse, and that considerable 

 invasion by inedible scrub had taken place. A 

 detailed survey in 1970 claimed that the ridges 

 were seriously affected by water sheet erosion, and 

 that up to 85 percent of this land class was un- 

 productive: the level areas were in fair condi- 

 tion, about 20 percent being affected by sheet 

 erosion; and the texture contrast soils, which 

 occur on only a small area, were seriously scalded 

 and wind-sheeted, about 70 percent of the land 

 class being affected. 



Only minor improvements have been under- 

 taken on this holding since early in the century. 

 These consisted of a small amount of subdivision 

 and one tank constructed about 1949. Consequent- 

 ly, a similar area has been available for grazing 

 throughout. 



The following grazing assessments are on 

 record. 



1918 — Estimated to carry 1 sheep to 2.6 hec- 

 tares. 



1932 — Lessee estimated holding could carry 1 

 sheep to 6.5 hectares. 



1934 — A surveyor estimated holding could 

 carry 1 sheep to 6 hectares, but the official esti- 

 mate was given as 1 sheep to 4.3 hectares. 



1948 — Assessed at 1 sheep to 4 hectares. 



1959 — Assessed at 1 sheep to 4.5 hectares. Land 

 Board assessed the holding at 1 sheep to 5.6 

 hectares. 



1970 — A Soil Conservation Service assessment 

 was 1 sheep to 10.1 hectares. 



The actual stocking record in 10-year means 

 from 1940 reads: 1940-1949—1 sheep to 4.2 hec- 

 tares actually carried; 1950-1959 — 1 sheep to 4.2 

 hectares actually carried ; and 1960-1969 — 1 sheep 

 to 8.9 hectares actually carried. 



A perusal of the annual figures since 1937 

 indicates that fluctuations in stock numbers have 

 occurred with rainfall, but recovery from 

 droughts is poorer, and the level of recovery is 

 becoming less with time, as pasture deterioration 

 continues. 



Traditional methods of assessing the ability of 

 land to carry livestock are not effective in this 

 situation. A method based on land inventory and 

 state of the vegetative resource is essential as a 



basis on which to develop restorative manage- 

 ment systems. 



However, serious repercussions can follow 

 when the assessed carrying capacity of a holding 

 is altered significantly. For example, if an over- 

 utilized and deteriorating holding is in debt, a 

 reduced carrying assessment may seriously aggra- 

 vate the landholders financial position. It is 

 understandable that the bodies charged with the 

 responsibility of administering the land do not 

 welcome sharp changes in concepts of land ca- 

 pability, because the whole economic structure 

 of the enterprise can be upset. 



A significant error in the overestimation of 

 grazing capacity can have, and has had, serious 

 effects on management. Overassessments have oc- 

 curred where the assessment has been based on 

 experience during a short period of above average 

 rainfall. Inevitably, dry periods follow, the land- 

 holder continues to hold high stock numbers, 

 hoping for a return to normal seasons, and se- 

 rious deterioration results. When land sales result 

 from overassessment. the incoming tenant is 

 forced to abuse the land in order to obtain the 

 returns he was led to believe would result. 



A method of assessing grazing capacity, based 

 upon an inventory of biological factors and re- 

 lated to past grazing experience, is valuable in 

 a number of ways. It can be used by land ad- 

 ministrators who need to know the grazing ca- 

 pacity of specific areas of land so that settle- 

 ment can take place on an equitable basis, the 

 risk of deterioration of the resource is reduced, 

 and a fair rental can be placed on the land. It 

 can be used by the range manager and advisor 

 in determining development policies, such as wa- 

 ter placement and fencing and grazing pro- 

 grams. 



The system can also be used when new lands 

 are opening up. provided that reasonable affin- 

 ities can be established with lands for which some 

 grazing history is available. If livestock numbers 

 are controlled and restricted to a number con- 

 sidered appropriate, the trend to deterioration 

 will cease. 



To attempt erosion control or erosion preven- 

 tion and simultaneously continue with overpopu- 

 lations of grazing animals is unrealistic. 



