Aprils Ag Advice by April Borders Even though we have received rain the last couple of weeks, it does not mean that the drought is over. Our spring rains have helped to replenish our soil moisture but long term forecasts show than we are headed for a hotter that normal summer and the potential for drought is still knocking at the door.
With our recent rains, we can expect to see a flush of growth in our pastures and rangelands, but we need to be cautious that we don't cause ourselves more long-term problems by using these pastures too soon.
Drought causes long-term effects and recovery is a long-term process. Management strategies need to be put into place now so that we can provide plants with the opportunity to maintain or improve vigor.
Stocking rate is the most important tool for grazing management, especially under drought conditions. Stocking rates for individual pastures should be based upon target levels of defoliation for key species.
The fundamental objectives of drought management are to 1) minimize damage to rangeland resources during and after drought and 2) minimize economic loss.
It is extremely important that we understand how a plant responds to moisture stress. Reductions in plant cover and vigor occur under serious, prolonged drought. Initial growth after winter or summer dormancy is produced with stored energy reserves. Short flushes of growth terminated by drought, grazing, hail or frost often deplete energy reserves and reduce forage production the following year. Plant survival during dormancy depends totally upon energy reserves. Plants must rely on stored energy for long periods of time when drought-induced summer dormancy is added to winter dormancy.
Drought reduces both root and shoot growth. More than 50 percent of the roots in grass plants die each year, even under average conditions. If leaf growth is limited, adequate carbohydrates will not be available for root replacement. Consequently, substantial reductions in root production can occur under drought conditions when healthy root systems are most critical.
The degree to which drought impairs a plant's potential for future forage production depends upon the stage of plant development at which growth stops. Reduced plant growth under drought conditions or excessive grazing before grasses head may reduce or eliminate formation of new buds and reduce or eliminate tillers.
The condition of drought and heavy grazing can cause severe reduction in forage production and plant vigor. It is extremely important that enough leaves remain during the growing season. Proper utilization during the growing season is generally the removal of 50 percent or less of the present, current year leaf and stem tissue by weight.
To put it in simpler words � "Take half and leave half" a phrase coined long ago. Proper utilization (leaf volume removed) will cause little reduc-
tion in root growth and plant vigor.
This year we will need to pay special attention to what our management program will be and also to when we can start grazing these areas. A general rule of thumb for grazing is to monitor your crop's growth. Once your grass gets to the three or four leaf stage you should plan on waiting another one to two weeks before turning in livestock. If the pasture was really dry last year and heavily grazed, give it a break. Wait until you have adequate regrowth and graze for only a short period of time. A 20 percent reduction in forage production can be caused by turning livestock in too early.
Your management plan should be in writing and you should consider a destocking plan as well. You need to know what your herd management plan is and have it ready to implement by June 1 if our weather moves towards a drought.
Some other important drought management considerations should be:
1. Resist the temptation to restock to former levels in the year following the drought.
2. Plan to delay the initiation of the summer grazing season by one to two weeks to enhance plant recovery.
3. Use rangeland resources efficiently.
4. Determine the availability of alternative or reserve forages.
5. Reserve 10 to 20 percent of your forage resources in case vegetation recovery falls short of expectations.
6. Calculate stocking rates for each pasture.
7. Make and implement decisions early to avoid crises.
8. Consider applying fertilizer to your pastures (50 lbs/acre) to help stimulate regrowth, if affordable.
If you would like to know more about drought management for your pastures stop by the Extension Office and pick up Publication EC 91-123, "Drought Management on Range and Pastureland � A Handbook for Nebraska and South Dakota." Excerpts of the publication were used in this article.
Just a foot note � starting Mondays in May through September, the Master Gardeners will be offering their expertise in our office. They will be operating the Garden Hotline for anyone with gardening questions and concerns. Their office hours will be from 8 to 10 a.m. You can reach them at 677-7111.