Planning for Drought

1. Planning for Drought On Colorado Rangelands

2. Colorado ranchers and rangeland managers can expect drought at least once every five years and should develop a drought plan

3. Effects of Drought on Plant Growth Depend on • Severity and duration of the drought • Health of vegetation going into it. • Plants in low vigor suffer more or die • Plants in good condition produce less • Period of growth and forage quality are reduced

4. Effects of Drought on Plant Growth • Plants may go dormant before the end of the normal growing season. • Drought increases the rate of natural die-off of plant roots. • Reduces vigor and forage production

5. Early Dormancy • Cause plants to enter a longer than normal dormant period • Plants become dependant on root reserves earlier in the year • Deplete root reserves needed for next springs growth • Reduce vigor on next years plants

6. Increased Root Die-Off Rates • Reduce ability to obtain nutrients and water from soil • Reduce plant vigor and forage production • Lengthen recovery periods

7. Effects of Drought on Animal Performance • If stocking rates are adjusted to carrying capacity animal performance may be maintained • If forage production does not meet animal requirements weaning weights may be reduced by 50-100 lbs. • Can cause delays in cows cycling (especially in first calf heifers)

8. Other Effects of Drought • Fewer water sources • Poor quality water sources decrease forage intake and performance • Livestock distribution problems

9. Managing during and after drought • Drought stricken ranges should be managed to promote root replacement and increasing plant vigor • Deferment from early spring grazing is important for reestablishment of vigorous root systems • Because forage production is less, ranges cannot be stocked at the same levels as in normal years. Reduction in grazing pressure is necessary to allow for recovery in a short time.

10. Management Options • Reductions in grazing pressure are necessary to allow for short term recovery • Haul water • Move livestock more often • Grazing systems that provide for root reserves or rest during normal years provide flexibility during times of drought • Provide for longer periods of rest /recovery • Increase number of pastures • Use other feed sources (crop aftermath and by-products)

11. Animal Management • Wean and sell calves earlier • Cull low performance cow/open cows early • Reduce number of replacements

12. What can be done on BLM and Forest Service Allotments • Use non-use for resource protection • Use more remote or less frequently used portions of the range • Use less reliable sources of water first • Design grazing systems that respond to drought conditions • Consider each situation on a case by case basis. • Keep healthy root systems and increased plant vigor as your goals during drought and normal years.