The current Drought Monitor shows 19% of Nebraska in the “abnormally dry” or “moderate drought” categories and in the shadow of large-scale drought in Kansas (97%) and Colorado (88%). Being curious about beginning soil moisture in non-irrigated situations, I installed Watermark soil moisture sensors in six non-irrigated, no-till locations in Webster, Nuckolls, Thayer, and Clay counties.
This quantitative information can be helpful as growers make planning and planting decisions. Granted, most planting decisions have already been made with inputs already purchased. Spring rains are also typically expected. However, information like this can help a grower be flexible in that planning should anticipated rains not be timely.
- The grower may choose to plant a more drought-tolerant crop like sorghum or a more drought-tolerant corn hybrid.
- A grower with livestock may choose to plant a feed/forage crop.
- A grower may choose to not terminate a growing cover crop such as rye, instead growing it for feed.
Soil moisture sensors were installed at 1-, 2-, 3-, and 4-foot depths in non-irrigated, no-till corn and soybean residue fields near Byron, Superior, Lawrence, Bladen, and Clay Center. The sensors were connected to Watermark dataloggers from the Irrometer company. Because the default soil temperature on the dataloggers is 70°F, a temperature sensor is also installed to ensure correct calibration of the soil moisture. This is because soil temperature during this time is dfferent (much lower) than 70°F.
Any farmer or crop consultant could do the same for his/her fields to determine the same information and wouldn’t need the datalogger. Taking weekly readings at the same time each week, or even daily at the same time, would also give one an idea of beginning soil moisture. It’s best to allow at least 48-72 hours for the sensors to equilibrate to the current soil moisture conditions. This process is essentially the same as when sensors are installed for irrigation scheduling. The difference is these are non-irrigated fields with no current crop growing. For additional information and videos on using watermark sensors, please see the Nebraska Agricultural Water Management Network website.
Nuckolls County is shown as in “moderate drought” on the Drought Monitor. At the Superior location, we were hoping to also install into actively growing rye and winter-killed forage to determine beginning soil moisture in those conditions. The rye is currently 6 inches tall in the tillering stage and the soil probe wouldn’t go in the ground beyond 6 inches, so no moisture sensors were installed. The soil probe would only go in 12 inches in the winter-killed forage consisting of sorghum-sudan and radishes; thus, soil moisture sensors weren’t installed in that field either.
Results so Far
During installation, the 3- and 4-foot depths at all locations (only 4-foot at Clay Center) seemed very dry. The soybean residue appeared drier than corn residue. Two sites are located near Lawrence, one in corn residue and one in soybean residue across the road from each other. That data shows differences in moisture between different residue types the most clearly. I was unable to install to the 4-foot depth at the Lawrence soybean residue location. At most other sites, a hammer was used to help install to 4 feet. However, given the difficulty in installing the 4-foot sensor, these graphs do not show them as dry or drier than the 3-foot at any location other than Bladen.
This could be due to several reasons:
- The soil textural properties at 4-foot depth could have more clay and higher soil bulk density in which the drier conditions would not be obvious or easily determined just by installation difficulty.
- There could be a compacted layer.
- The dryness or wetness of any given soil layer at any given time is a function of various factors including the farming history of the field, previous several years of root development in different layers, previous year’s precipitation amount and distribution during the season as well as during off-season, evaporation rate, and water uptake pattern of the crop from different soil layers as water update from different soil layers varies and also varies with time during the season.
- The 4-foot layer may not actually be drier than the 3-foot layer.
Because only a few days of data are shown thus far, it is difficult to make a determination at this time. Data will continue to be collected until each field is planted and the results will be posted weekly on my blog. Additional information regarding each location is in each figure caption.
A special thank you to each farmer cooperating with me on this effort and to Dr. Suat Irmak for providing additional equipment and advice on this effort.
The rain was welcome on Thursday but the wind and hail damage that came were devastating to a good portion of the County. I’m so sorry to all of you affected….for some of you, this is two years in a row of severely hail damaged or totaled out crops. We are thankful the damage wasn’t worse. You can see more pictures here.
So the big question is what do you do now? Ultimately, each field will need to be assessed on a case by case basis. The following are our NebGuides for hail damage to corn and soybeans. For the most part we were in brown-silk to blister for corn and late pod-beginning seed in soybean (R4-R5). The concerns I have right now are stalk quality, disease, grain filling, and the amount of diseased grain we may have due to mushy areas on hail-damaged cobs right now. Several years ago, we watched how severely hail-damaged corn a little later in the season turned brown and died. We also know that southern rust is in the area and while much of the leaf tissue in the County is damaged, it is still in the County in other fields and south of us. The Puccinia polysora fungus that causes southern rust, when severe enough, will infect and cause pustules on the stalks. With the wounding and low leaf area for photosynthesis, stalk strength is a concern and fungicides may be a consideration depending on potential yield loss-again need to assess on a field by field basis.
I talked with a number of people on Friday regarding thoughts on silage, green chop, haying/baling, planting cover crops, etc. Dr. Bruce Anderson, UNL Extension Forage Specialist, said the most common salvage operation for corn damaged by hail, wind, drought, or other calamities is to chop it for silage. Don’t be in a hurry, though. Standing corn currently could be over 80 percent moisture. The easiest way, and maybe the best way, to lower moisture content is simply wait until some stalks start to turn brown. Waiting also allows surviving corn to continue to add tonnage.
But in some of our damaged fields, I don’t think we can wait to make silage. Bruce also shared you can reduce moisture by windowing the crop and allow it to wilt one-half to one full day before chopping. You also could mix grain or chopped hay to freshly chopped corn to lower the moisture content. It takes quite a bit of material for mixing though – about 7 bushels of grain or 350 pounds of hay to lower each ton of silage down to 70 percent moisture from an original 80 percent moisture. That’s 7 bushels grain or 350 pounds of hay for each ton of silage.
Or, you can allow that windrowed corn to dry completely and bale it as hay. Be sure to test it for nitrates before feeding. Grazing might be the easiest way to use damaged corn, and this is a good way to extend your grazing season. You might even plant some corn grain or sorghum-sudangrass or oats and turnips between rows to grow more forage for grazing if you can wait until late fall before grazing. Be sure to introduce livestock slowly to this new forage by feeding them before turning in to reduce the chances of digestive problems. Also, strip graze the field to reduce trampling losses and get more grazing from the corn.
As I set here writing, we went from wearing t-shirts yesterday to receiving freezing rain and sleet today! The precipitation is much welcomed and it’s nice to see spring bulbs coming up and the grass turning green! But we’re unfortunately not out of the woods yet regarding this drought, and may not be for some time.
This Thursday, April 11, Elizabeth Killinger, UNL Extension Educator in Hall County, will be talking to us about gardening during drought. Come enjoy an evening of learning about drought-tolerant plants and ideas for your landscape! The evening begins with a light supper at 5:30 p.m. and we plan to be finished around 7:00 p.m. There will be no charge for this workshop, so please come and invite your friends and your youth who enjoy gardening as well!
Also, if you would like to bring some plants for exchange, you are welcome to do so and share with others! Please call the Clay County Extension Office at (402) 762-3644 or Jenny at email@example.com to let us know you’re coming so we can plan for the meal. See you then!