Range conditions and trends

1. LECTURE 6:
RANGE CONDITION AND TREND

2. RANGE CONDITION DEFINED
• A STATE OF HEALTH OR
PRODUCTIVITY OF BOTH THE SOIL
AND THE FORAGE OF A GIVEN
RANGE IN TERMS OF WHAT IT
COULD OR SHOULD BE UNDER
NORMAL CONDITIONS

3. RANGE CONDITION CLASSES
• EXCELLENT CONDITION
• GOOD CONDITION
• FAIR CONDITION
• POOR CONDITION

4. EXCELLENT RANGE CONDITION
• 76-100% OF CURRENT VEGETAL
COVER COMPRISES DECREASERS &
INCREASERS
• 0 TO 24% CONSISTS OF INVADERS

5. GOOD RANGE CONDITION
• 51-75% OF CURRENT COVER
COMPRISES ORIGINAL OR CLIMAX
VEGETATION

6. FAIR RANGE CONDITION
• 26-50% OF CURRENT COVER
COMPRISES ORIGINAL OR CLIMAX
VEGETATION

7. POOR RANGE CONDITION
• 0-25% OF CURRENT COVER
COMPRISES ORIGINAL OR CLIMAX
VEGETATION

8. RANGE CONDITION INDICATORS
• ECOLOGICAL STATUS
• FORAGE PRODUCTION OR YIELD
• SOIL CONDITION
• PLANT VIGOUR
• ANIMAL CONDITION

9. ECOLOGICAL STATUS
• JUDGED BY THE PROPORTION OF
THE PLANTS WHICH DECREASE,
INCREASE OR INVADE THE RANGE
UNDER GRAZING

10. FORAGE PRODUCTION OR YIELD
• CONSIDERS THE AMOUNT OF
CURRENT FORAGE WHICH COULD BE
PRODUCED ON A GIVEN AREA UNDER
THE BEST POSSIBLE MANAGEMENT

11. SOIL CONDITION
• CONSIDERS THE AMOUNT OF BARE
SOIL WHICH IS VISIBLE AND THE
DEGREE OF EROSION THAT HAS
TAKEN PLACE
• CONSIDERS THE PRESENCE AND
ABSENCE OF LITTER

12. SOIL CONDITION
• LITTER PROTECTS SOIL FROM EROSION
• ITS PRESENCE INDICATES THAT PAST
GRAZING HAS NOT BEEN ABNORMALLY
HEAVY
• ACCUMULATION OF LITTER GENERALLY
INDICATES IMPROVEMENT IN RANGE
CONDITION

13. PLANT VIGOUR
• TAKES INTO ACCOUNT OF:
1) ABUNDANCE OF SPECIES
2) SIZE OF PLANTS
3) HEIGHT OF SEED STALKS
4) NUMBER OF SEED STALKS PER
PLANT
5) DISTANCE BETWEEN PLANTS
AND
6) AGE OF GROUPS OF PLANTS

14. ANIMAL CONDITION
EXCELLENT: COW WT 430KG
80% CALF CROP
CALF WT 181 KG
GOOD: COW WT 386KG
70-79% CALF CROP
CALF WT 159-180KG

15. ANIMAL CONDITION
FAIR: COW WT 318 KG
50-69% CALF CROP CALF
WEIGHT 136-158
POOR: COW WT LESS THAN 318
KG LESS THAN 50% CALF
CROP CALF WT LESS THAN
136KG