Extension Update from Jenny Rees

UPCOMING EVENTS:  

May 31:  Crop Science Investigation (CSI), 5:30 p.m., York Extension Office, RSVPjrees2@unl.edu
June 6:  Winter Wheat Field Day-Washington Co., 6pm, RSVP Nathan Mueller (402) 727-2775
June 7:  Winter Wheat Field Day-Fairbury, 6:30 pm, RSVP Randy Pryor (402) 821-2151
June 12:  Generational Transition for Ranchers, Noon-5pm, Belvidere Community Bldg, RSVP erin.laborie@unl.edu or (308) 268-3105
June 13:  Summer Grazing Tour (Reynolds, Belvidere, Bruning), RSVP:  erin.laborie@unl.edu or (308) 268-3105
June 16:  Field Pea, Forage, and Cover Crop Tour, Hastings-Webster Co, RSVP:sstepanovic2@unl.edu or (308) 352-4340
June 17:  Cow-Calf Management Field Day, 1pm, Cuming County,  Larry Howard, 402-372-6006
June 19:  Winter Wheat Field Day-UNL Research Farm North Platte, 3 p.m., RSVP Rodrigo Werle (308) 696-6712
June 20:  Winter Wheat Field Day-Henry J. Stumpf Wheat Center Perkins Co, 9am, RSVP Rodrigo Werle (308) 696-6712
June 22:  Cover Crop Conference, 2 p.m., Holthus Convention Center York.
June 28:  South Central Ag Lab Weed Science and Cover Crop Field Day, SCAL near Clay Center, registration 8am, Weed Program 8:30-Noon, Free lunch, Cover Crop Program 1-3pm, Register:  http://agronomy.unl.edu/fieldday
July 10-11:  Youth Tractor Safety Class, 8am, Grand Island College Park (308) 385-5088.
July 18:  Crop Management Diagnostic Clinic:  Soil Health, ARDC (now ENREC) near Mead
Aug. 2:  Crop Management Diagnostic Clinic:  Precision Ag Training, ARDC (now ENREC) near Mead
Aug. 8:  Soybean Management Field Days, North Platte
Aug. 8-9:  Nebraska Grazing Conference, Kearney
Aug. 9:  Soybean Management Field Days, Ord
Aug. 9:  Nebraska Cover Crop Conference, during Lancaster Co. Fair at Fairgrounds
Aug. 10:  Soybean Management Field Days, Auburn
Aug. 11:  Soybean Management Field Days, Tekamah
Aug. 23:  Crop Management Diagnostic Clinic:  Soybean Production Training, ARDC (now ENREC) near Mead
Aug. 24:  Crop Management Diagnostic Clinic:  Corn Production Training, ARDC (now ENREC) near Mead
Aug. 24:  York County Corn Grower Plot Tailgate, 5-7pm, Road I, NE¼ of 29-11-3, York County.

Farm Finance Clinic Sites and Dates To sign up for a clinic or to get more information, call Michelle at the Nebraska Farm Hotline at 1-800-464-0258.

As we reflect on Memorial Day, I’m grateful for those who paid the ultimate sacrifice for our freedom and for their families left behind.  Freedom is not free and we are so blessed in the U.S.A.!

Crop Updates:  Lots of questions this week regarding corn and soybeans looking sickly.  Yellow banding can be seen on corn plants from the cold temperatures at various times of the plant’s growth.  Some have been packed with mud from rains or have wind-whipped leaves.  I’m also seeing some evidence of seedling diseases caused most likely by Pythium sp. in portions of fields with excess moisture. 

Soybeans are also struggling in different situations.  I’ve been asked to look at fields where soybeans appeared to be dying and/or had discoloration of the cotyledons and hypocotyls.  Most of what I’m seeing thus far with the discoloration of cotyledons and hypocotyls have been in fields where a pre-emergent herbicide program containing a PPO inhibitor was used.  These are helpful products in reducing weeds.  We’ve just seen this in the past as well after rain events that the chemical can be rain-splashed onto the cotyledons and/or the plant is unable to outgrow the effects of the chemical quickly enough in comparison to the damage observed.  Hopefully most of these fields will still be ok with plant stands if enough plants can grow out of it; we’d say to leave plant stands of at least 75,000 plants per acre because of the way soybeans compensate for reduced populations without a significant yield effect.  There may also be situations of damping off diseases occurring in soybeans.  They keys are to look at where the damage is occurring.  Discoloration of the roots/below-ground stem would most likely be due to seedling diseases whereas, PPO injury will occur on the cotyledon and hypocotyl-so essentially above the soil.  There could be instances where the stress of herbicide damage is also complimentary to Rhizoctonia root rot, but I haven’t sent any samples in to confirm this.  The following article is from a few years ago, but summarizes the situations in which damage could more likely be anticipated:  http://go.unl.edu/2jbf. 

Wheat is in various stages of pollination to beginning filling.  Stripe rust and leaf rust continue to spread on leaves but wheat is past the point of fungicide application if it is over 50% pollinated.

Extension Positions:  Both the Webster and Clay County Extension Educator positions have received approval to be filled as they are deemed critical positions.  Extension Educator – Beef Systems Webster County (https://employment.unl.edu/postings/54252). Review of applications will be 06/10/2017.  Extension Educator – Cropping Systems Clay County (https://employment.unl.edu/postings/54283). Review of applications will be 06/20/2017.

Installation of ET gages and Soil Moisture Sensors:  Now is the time to get your ET gage set up if you haven’t already done so.  Make sure to use distilled water in the main container and be sure to also fill the ceramic top before putting in the stopper.  For best results, be sure there are no air bubbles in the stopper tube.  It’s also wise to change the ET gage cover and white membrane at least every few years.  These can be obtained from your local NRD and sometimes your local Extension Office.  You can view all our resources, online ET gage site, and demonstration videos for installation at:  http://water.unl.edu/category/nawmn. 

Regarding installing watermark sensors, some best practices we’ve learned include the following.  First, prime the sensors by allowing them to soak for at least 24 hours.  They should read 10kpa or less when you read them with a hand-held meter.  If they don’t, you can allow them to soak longer to see if they eventually read less.  A general rule of thumb we use is to replace any sensors that read greater than this during priming.  We also would like them to dry out to 199kpa (so a full wet/dry cycle) before installing.  For installation, they should be installed after soaking in water.  I use an ag consultant’s tube to install the actual foot where the sensor is placed and the regular soil probe for the feet above that.  For example, I use the ag consultant tube for 1 foot sensor.  For 2 foot sensor, I use regular soil probe tube on the first foot and the ag consultant tube for the second foot.  Never make a slurry for watermark sensors or pour water down the hole.  Instead, I wet the pvc pipe from the bucket water and then quickly push the sensor into the hole (don’t use WD40).  Make sure the bottom of the sensor is at the bottom of the hole.  Any air gaps will make the sensors read incorrectly.  Another best practice is to never install the sensors in saturated soil.  When this occurs, we’ve found a thin layer of clay forms on the sensor which then dries around the sensor and results in dry readings.  This is also easily corrected by removing the sensor later, quickly rewetting, and reinstalling in the same hole.  It’s just nice to have it installed correctly the first time.  I also look for even spacing of plants-avoid doubles and skips in the field to ensure the sensors are only reading from one plant on either side of it.  While it requires more walking in some situations, we recommend to avoid the first and last pivot towers as they tend to vary in water application.  We also recommend to install in the most consistent soil type for the field or install more sets of sensors for varying soil types.  Following these practices will help ensure your readings are more accurate.  Many problems with sensor readings can be traced back to sensor installation.

Horticulture Updates:  Lawn Care:  A second application of fertilizer to cool season lawns (if needed) can be applied up through June 1 (according to our UNL Lawn Calendars) at a rate of 0.75-1lb/1000 sq. ft.  White grubs adult beetle (masked chafers and May/June beetles) are emerging. If a lawn had white grub damage last season and an insecticide application is planned for this season, wait until June or early July to apply preventive insecticides. Wait until August to apply curative products.

Bark Splitting/Sloughing:  Bark sloughing continues on ornamental pears, maples, lindens and crabapples. It is due to sudden cold temperature injury to the trunk cambium, most likely during November 2014. If trees are killed by a disease, such as fire blight; this too may lead to bark sloughing off. There is nothing to do for these trees but provide ideal growing conditions and enjoy them as long as they survive.