Extension Update by Gary Zoubek [June 14, 2012]

Well, it was sure to get some more rain in the middle of the past week!  The ETgages that I’ve been monitoring dropped between 2.10 – 2.20″ for the week.  That’s considerably more than last week and the crops are continuing to growing so the crop coefficient is steadily increasing.  The early planted corn field I’m monitoring is in the 8-9 leaf stage, so the crop coefficient is .51for 8 leaf corn and .69 for 10 leaf corn, so for the week we used between 1.10″.  We estimate the crop water use by multiplying the crop coefficient times the ETgage drop.It’s getting time that we could use another rain, but the fields I’m monitoring are still in great shape!  The Watermark sensors averaged 51 at 1’, 9 at 2’, and 16 at 3’ and since the field was actually above field capacity following the rains we received around Memorial Day, we have only used about .33” based on the Watermark Soil Sensor readings and have only used that from the top foot!  

We are in about the same shape in the soybean field that is now at V4.  We’ve got the 4th set of trifoliate leaves.  The sensors in the soybeans averaged 47, 11 and 2 at 1’, 2’ and 3’ respectively!  We typically don’t recommend irrigating them until they reach R3 stage, so we should be in good shape still for a while!  By watering too early we get beans that are taller, use more water, but don’t yield more, so it’s important to hold off and apply it when it is need!

So, for both corn and soybean, it’s important to allow them to continue to root down rather than irrigate at this time!  We have installed several different types of soil water monitoring equipment in this year’s York County Corn Grower plot that Ron & Ray Makovicka are doing for us.  I hope to share info about how these tools are going.  We installed some of the newer three wire Watermark Sensors in the fields so I can get the reading at my computer, iPhone, or iPad.  Monday morning the sensors were reading 62, 15 and 2 at the 1’, 2’ and 3’ depths, so these two fields are reading about the same.  I’ll try and share more info about these systems in coming weeks!

I’ve received a couple questions about Goss’s wilt and we did have it confirmed in York this spring.  Check out the articles at CropWatch this week regarding this disease at http://cropwatch.unl.edu.  The latest issue includes some stories on rootless corn as well as rapid corn syndrome, so check it out!

Finally, if you are interested in the latest light trap data from the South Central Ag Lab, check it out at:  http://scal.unl.edu/Insect/2012_Light_Trap_Report.shtml.

PQA Plus Webinar Planned
It’s more important today than ever that livestock producers care for their animals and get certified every three years.  We will be hosting this training at our office on June 19th at 7:00 p.m.  I’d like to remind all area pork producers that need this training to get the date down on their calendar and plan to attend!

LEAD Applications Due June 15
I mentioned it last week, but I’d like to encourage area residents that June 15th is the deadline for making applications for Nebraska LEAD (Leadership Education/Action Development) Group 32.  They will select up to 30 motivated men and women with demonstrated leadership potential from five geographic districts across Nebraska.

The leadership training focuses on interpersonal skill development, communications, education, public policy issues, economics, community development, natural resources, and social and cultural understanding and is designed to prepare the spokespersons, problem-solvers and decision makers for Nebraska and its agricultural industry.

Applications are due no later than June 15 and are available via e-mail from the Nebraska LEAD Program.  Please contact Shana at sgerdes2@unl.edu.   You can also request an application by writing Room 318 Biochemistry Hall, University of Nebraska-Lincoln, 68583-0763 or by calling (402) 472-6810.  I would sure encourage you to consider applying for this great program!

Yard & Garden

The ETgage in front of our office with a #30 grass cover dropped 1.70″ this past week!  So for the week, we averaged .24″ per day or double of last week!

I received three turf updates this weekend!  They were about irrigating turf, crabgrass control and avoiding summer fertilization!

They indicated that with the soil and air temperatures a month ahead of schedule this year, turf irrigation is also ahead of schedule. Irrigation is important if you want to maintain a green lawn all summer. However, cool-season grasses mowed at lawn height can withstand far more drought stress than they are usually credited for and thus less irrigation can be used than one might expect.

Deep and infrequent irrigation is best for turfgrass health (optimum rooting, minimal pest pressure, etc).  In other words, do not irrigate until you see the first signs of drought stress, which is “footprinting” or a bluish-gray color to the turf in mid-afternoon.  Most turf can easily withstand this type of drought stress for a short period. Once these symptoms are seen, irrigate that evening or preferably the next morning wetting the soil to the depth of rooting.  Then do not irrigate again until you see the signs of drought stress, which may be few days to a few weeks depending on the species and health of turf, soil type, and most importantly the weather.  Irrigating in this fashion will maintain a healthy lawn with a minimum of water.

Cool-season grasses like Kentucky bluegrass and tall fescue should be fertilized only lightly in the spring and summer with most of the nitrogen applied after Labor Day. Though this year’s extended growing season will require slightly more N for the relatively same performance as typical years, spring and summer N applications should still be minimized. As growth of cool-season grasses slow down with heat and water stress of June, a common urge is to fertilize to enhance dark green color and stimulate growth. If want to fertilize at this time you only want to put a low rate of say 0.25-0.75 lbs N/1000 sq ft.  If you cannot do that, you may be better off to wait to fall to fertilize again.

Over-fertilizing in the spring and summer can lead to:

1. Excess growth, increasing frequency of mowing.
2. Excess top growth consuming all storage carbohydrates which translates into poor rooting and inadequate performance in heat/drought stress.
3. Increased summer diseases like brown patch in tall fescue

Check out the complete articles at:  http://turf.unl.edu/.

For all the latest horticulture updates, check out our Environmental Homepage: http://environment.unl.edu/.  It includes links to Backyard Farmer, Turf iNfo, Acreage Insights and as well as horticulture updates with many timely tips!