Tips to Improve Rainfall Effectiveness

    The title of this column takes an optimistic look into the future, and that is, we are one day closer to a good rain!  If you are in the livestock business, utilizing native Texas rangeland, you know that rainfall is the major limiting factor to your production potential.  Yes, there have been attempts with technology, like cloud seeding, to increase precipitation, but the fact remains technology has not ended the historic drought that we are experiencing.
    So if technology cannot turn on the water from the sky when we need it, we have to look at management tools that can improve the effectiveness of rainfall events when they do occur.  Research has shown that the amount of rainfall runoff from a particular range site is directly related to vegetation on the site.  Generally speaking, sites that are dominated with plants that provide good ground cover hold rainfall on the site the best.  In contrast, sodgrasses or bare ground do not provide sufficient plant litter cover to allow for effective infiltration of the rainfall, thus we see heavy runoff and soil loss.
    Evaporation is another source of water loss on our rangelands. The amount of water lost through evaporation from the plant canopies or soil surface is related to the intensity of the rainfall event and the weather conditions that follow the event.  As you move west in our state, this evaporation loss increases.
    We know that not all plants found on our rangelands are desirable for livestock and wildlife production.  Brush or toxic and /or noxious weeds deplete water that could be used for more desirable species.
    So with these factors in mind, here are some tips to help improve rainfall effectiveness on our rangelands.  First we should work on reducing runoff, as this can represent a serious loss of water from our ranch.  Research has shown that rangeland infiltration rates generally increase as total plant cover increases.  The plant cover slows the water movement across the soil surface allowing more time for water to infiltrate before being lost down creeks and draws.  Plant cover also protects the soil surface from rain drop splash.  Vegetation type also affects runoff.  Bunchgrasses are more effective at reducing runoff than sodgrasses, while Oak mottes produce even less runoff.  Livestock stocking rates, grazing systems, and species of livestock are all major management tools that can be used to manage the range forage base as well.
    Another important factor to improve rainfall effectiveness is reducing the undesirable weed and brush species.  It has been estimated that mesquite uses 100 gallons of water for each pound of above ground plant growth produced.  Perennial grasses are more efficient users of water requiring from 40 to 75 gallons of water for each pound of above -ground biomass produced.  The amount of water used by unwanted plants can vary greatly from ranch to ranch depending on the species of plants present and their density.  Having a plan to manage these undesirable plants can help improve the efficiency of water use for livestock and wildlife.
    The harvest of vegetation by livestock must be limited to ensure regrowth and reproduction of perennial range vegetation.  An old rule of thumb goes something like this, 50% of forage should be left standing for health of the plant, 25% will be lost to trampling, weathering, or consumption by insects and small mammals, which leaves only 25% that is actually consumed by livestock.  For most of us, that means we should have reduced stocking rates a long time ago.
    Bottomline, rainfall represents the single most limiting factor to livestock production on our Texas rangelands.  We have to do the best job possible at managing these range sites so that when we are blessed with a rainfall event, our rangelands can take full advantage of that precious water resource and keep it on site, and store in the soil profile, for the dry times that will come again.  

Grain Sorghum Management in Times of Drought

    Typically by this time of year, grain sorghum is being planted with hopes that this drought and heat tolerant crop will produce yields that will help carry the local farm economy.  There is one major problem this year however, you have to have some soil moisture to produce a grain crop.  Currently we have very little stored soil moisture in Nueces County and precipitation forecasts are not desirable.
    So if you are considering what to plant, know that it takes more water to produce grain than a forage crop, so in order to minimize risk one might consider growing forage sorghum for hay or silage in place of a grain crop. Moreover, during periods of drought, hay shortages are often present providing a good market for hay.
    If the decision is made to produce a grain crop, management strategies should be altered to minimize risk. Hybrid selection, planting date, fertilizer rates, seeding rates, and weed control
strategies may all need to be altered.
    So when considering which hybrid, generally this will be shorter maturing hybrids. With  sorghum, not only should length of maturity and drought tolerance be considered, but also try to find a hybrid that produces fewer tillers. These strategies tend to shift more of the available water into producing grain rather than vegetation. Yield potential will not be as high, but the risk of producing little or no grain will be minimized.

    Since potential yield will be reduced during a drought, fertilizer rates should be reduced. As a general rule of thumb fertilizer rates should be reduced 25% from what is normally applied.
Also consider applying no more than one-third of the needed N fertilizer preplant. The rest of
the N can be applied as a side-dress application 30 days after emergence. Only apply the sidedress application if the prospect for producing grain is good.
    Planting date should be flexible. Do not plant sorghum in dry soil unless you are confident that rainfall is eminent. Wait as long as possible for some precipitation to wet the soil where the seed will be placed. Be prepared to plant immediately following the precipitation event.
    Weeds that are drought stressed will be more difficult to control. For this reason using a preemergence herbicide is usually the best option. However, pre-emergence herbicides will require rainfall to move them into the soil or must be mechanically incorporated. If no rainfall occurs within six days after applying the herbicide consider incorporating with a rolling cultivator or harrow. Try not to incorporate the herbicide more than 2 inches. If post emergence herbicides must be used, treat weeds when they are small (less than 3 inches) and are easier to control.
    It is very important that seeding rate of sorghum be reduced when experiencing drought
conditions. Reduce seeding rate at least 25% from normal rates. Also consider using a skip row
pattern of only planting ever-other-row or a two-in one-out arrangement. This will tend to allow
the crop to better utilize any available water that may be present in the soil.
    Finally, following harvest, tillage operations should be kept to a minimum in order
to maximize precipitation storage in the soil for next year’s crop.

Take the 40 Gallon Challenge

    As the drought worsens, our local water supply continues to decrease as we are currently in Stage 2 of  Mandatory Water Restrictions.  That means that outdoor watering is restricted to before 10 am and  after 6 pm.  In addition large property owners must obtain approval for a watering plan and Commercial Nurseries must use hand held devices, drip or sprinkler systems to irrigate.
    To help facilitate water conservation, the Texas A&M AgriLife Extension Service is strengthening its challenge to Texans to save millions of gallons of water annually as well as money on their monthly water bills.  The 40 Gallon Challenge is a program that calls on residents and businesses to reduce their average water use by 40 gallons per day, according to Dr. Diane Boellstorff, AgriLife Extension water resources specialist in College Station.
    Boellstorff became involved in the voluntary national program in 2011, serving as the Texas representative.  After one year, she and AgriLife Extension economist Dean McCorkle in College Station completed an economic impact study in November, which showed that Texas participants, based on average municipal rates, were saving an estimated $299,000 a year, in addition to the water savings.
    “At the time that we did the impact statement, we were able to count 80 programs from 89 counties, and participation continues to increase,” she said. “For example, the impact statement mentions 1,050 participating households saving 71 million gallons of water annually, but today’s numbers are 1,152 participating households saving 80 million gallons annually.”
That change has come in only three months. Boellstorff said many AgriLife Extension agents are beginning to deliver the program in their local counties. She is also making presentations to spread the program across the state.
    This water resource conservation tool is one of many programs initiated and supported through the Southern Region Water Resource Project, funded through the U.S. Department of Agriculture – National Institute for Food and Agriculture. Dr. Mark McFarland, AgriLife Extension state soil fertility specialist in College Station, is the project director.
    The 40-Gallon Challenge allows Texans to compete against other Americans who are taking the challenge in their states. At the program’s website, www.40gallonchallenge.org, Texans can pledge to adopt water-saving practices and see how many gallons of water they can expect to save.  The website also shows the most popular practices being pledged, the practices that are saving the most water daily, and counties and states that are pledging the most daily savings, Boellstorff said.
    Currently, the top water savers in Texas are “reduce irrigation station runtimes by two minutes,” “use a broom instead of a hose to clean driveways and sidewalks,” and “fix a leaky toilet.” In Texas, the three counties registered to save the most gallons are Collin, Ellis and Dallas.
    To start saving water and take the challenge, go to the website; http://www.40gallonchallenge.org/    and complete the checklist of water-saving practices, its time for Nueces County residents to make a mark on the map.  The checklist includes both indoor and outdoor water-saving tips.

DROUGHT FEEDING MANAGEMENT FOR CATTLE

Drought of 2012 - limited standing forage in December

  Here is South Texas, most of our pastures are very short in standing forage at this time, while the drought continues to persist.  Here are some tips offered by Dr. Dennis Herd for consideration in feeding cattle during drought.

Where pasture is lacking in amount as well as quality, the following suggestions are offered:
    If only slightly limited, the feeding of range cubes (20% protein) or mixtures of grain and
cottonseed meal at rates of 3 to 5 pounds per cow daily may work for a while. Cubes with
a large amount of natural protein and a low crude fiber level (less than 10%) would be
preferred.

    When pasture becomes extremely short, purchase of hay or a replacement feed for the
pasture must be considered as well as selling of stock. Remember that most grass hay has
only 50 to 65% the energy content of grain so that one pound of grain can replace 1.5 to
2.0 pounds of hay. A pound of grain will only replace 1.2 to 1.4 pounds of alfalfa hay. It is necessary to start cows on grain slowly and feed so that all cows have opportunity for their share of the feed. It is possible to feed up to 80% grain in a maintenance diet for British bred cows, but such high levels should not be considered for Brahman cattle. All cattle need some forage in the diet to minimize digestive problems.

In the absence of sufficient nutrients, particularly energy, cows lose considerable weight. When such weight losses occur, milk production decreases and reproductive activity may cease. The end result is light-weight calves and unbred cows. To prevent such undesirable effects, cows either must be provided sufficient nutrients to avoid weight losses and maintain production requirements or they must be relieved totally or partially from body stresses.

For more information related to drought management consult this web site; http://texashelp.tamu.edu/004-natural/droughts.php