Category Archives: Lawns
Soybeans: The past week I was mostly in soybean fields taking harvest notes for on-farm research or helping harvest plots. The non-irrigated yields have been better than anticipated for the beans just dying in fields; I can’t help but wonder what they could’ve been had there been rain in August! As noted last week, there’s a definite difference in varieties as to the number of 4-bean pods. Some varieties are loaded with pods and it’s not hard to find 4 bean pods. Others in our variety studies have a majority of 3 bean pods and it’s rare to see 4 bean ones. It will be interesting to see yields, and may be something to observe in varieties on your farms if you’re curious. Will also take a look at solar radiation data as several commented the smoke seems to be impacting drydown of irrigated soybeans.
Woolly Bear Caterpillars are noticeable in soybean fields as are stink bugs and loopers; however, woolly bears are also on the move from soybean fields to find green plant tissue elsewhere. In past years, it’s not uncommon to find them crossing roads. I had a couple of reports towards the end of last week of them demolishing garden plants and shrubs. They probably don’t need controlled in all cases and not all products are as effective on them. Bifenthrin is labeled to be effective on them and can be used on a variety of plants, so that may be one option if treatment is necessary.
Stalk Nitrate Test: A corn stalk nitrate test can provide an indication if the amount of nitrogen for the corn plants was low, high, or sufficient for that year. This test involves taking an 8” sample of the stalk. It should be taken 6” above the soil line and go to 14” above the soil surface. All leaf sheaths should be removed from the stalk. 15 samples should be collected 1-3 weeks after black layer from a one acre area that represents a larger area (same soil type, etc.). Sample other areas of the field with different soil types or management. Then place stalk samples into a paper bag (don’t use plastic) and ship the samples within one day or refrigerate until shipping. It’s important to take the sample from 6-14” above the soil line because all the research to create the test was done from that area of the stalks. Also note that situations like a good grain fill season, drought, or poor ear development can all impact the test providing lower or higher numbers. This test isn’t to be used to determine nitrogen rates. It just gives a ballpark over time regarding if too much, too little or sufficient nitrogen is available on a consistent basis over years in a field. If the test results over several years are consistently high (greater than 2000 ppm), it would suggest the grower could reduce nitrate rates without impacting yields. If too low, the grower could consider additional nitrogen or adjust nitrogen management within the field. You can read more about this test here: https://store.extension.iastate.edu/product/Use-of-the-End-of-Season-Corn-Stalk-Nitrate-Test-in-Iowa-Corn-Production. My colleague, Aaron Nygren, also created a short Twitter video here: https://twitter.com/ColfaxCountyExt/status/1305982739791966208?s=20.
Sensors and ET gages: A quick reminder to remove any sensors for irrigation scheduling and ET gages from your fields before harvest. In the midst of everything else, it can be easy to forget about them!
Fall Lawn Fertilization: Early September is one of the best times to fertilize Kentucky bluegrass and tall fescue. There’s still time to apply if it’s not yet been done. One application may be all that’s needed on older lawns (10 to 15 or more years). Use a fertilizer with at least a 50% slow release nitrogen source. Two fertilizer applications are recommended on younger lawns; one in late August/ early September and one about mid-October. Use a slow release nitrogen source on the first application and a fast release nitrogen source on the second one. Avoid fertilization after late October as plant uptake is low. This causes nutrients to leach away during winter or linger in soil until spring leading to early growth. More info: How to Fertilize Turfgrass This Fall.
Crop Updates: For the past week, crops used around 0.22” per day in the York area, around 0.20” as one goes east towards Ithaca and closer to 0.25” per day going south towards Harvard and Guide Rock (based on High Plains Regional Climate Center data posted on CropWatch).
- Corn at Beginning Dent needs 5” of water (approximately 24 days to maturity)
- Corn at ¼ milk needs 3.75” (approximately 19 days to maturity)
- Corn at ½ milk (Full Dent) needs 2.25” (approximately 13 days to maturity)
- Corn at ¾ milk needs 1” (approximately 7 days to maturity)
- Soybean at beginning seed (R5) needs around 6.5” (approx. 29 days to maturity)
- Soybean at full seed (R6) needs 3.5” (approx. 18 days to maturity)
- Soybean with leaves beginning to yellow (R6.5) needs 1.9” (approx. 10 days to maturity)
Spent a lot of time last week looking at ear development in fields, particularly those impacted by the July 8th windstorm. Also appreciated a long conversation with John Mick with Pioneer on what he was seeing. For the most part, I’m seeing a lot of ‘normal’ ears that vary in the amount of tip back from lack of pollination and/or kernel abortion. Less commonly seen are ears with 3/4 husks. On plants that were pinched, continue to see messed up secondary and/or tertiary ears after the loss of the primary ear. On plants that bent and righted themselves, seeing a variety of things. Some are more ‘normal’ while other ears are much smaller that either didn’t pollinate well and/or had kernel abortion.
Last month, had mentioned a curious thing regarding how many hybrids are putting on multiple ears on the same ear shank, on the primary ear node. It’s far more than I’ve ever seen before. In sharing some observations with Dr.’s Tom Hoegemeyer and Bob Nielsen, they share it’s most likely a genetic X environmental response under excellent growing conditions or some other phenomena. As I continued to see these ears in fields and husk them back, for the most part, they don’t appear to be detrimental to the main ear, which is good. So it’s more of a curiosity than anything.
Many of us probably don’t examine ear shanks much in comparison to the ears. However, when one does look at ear shanks, one will observe they are similar to the corn stalks in that there are nodes and internodes. Each node also produces a leaf (in this case a husk leaf) instead of a collared leaf such as what happens on the main stalk. And each node (on stalk and on ear shank) has an axillary meristem which allows for ear development. Normally, there must be genetic or hormonal suppression so that only one main ear is formed on a shank at a stalk node. It’s not uncommon for us to observe an ear on different nodes of the stalk (ex. Nodes 12 and 13). What is more uncommon is to observe multiple ears on different nodes of the same ear shank, such as what is being observed this year.
Renovating Lawns: If your lawn is in need of repair, now through mid-September is a great time-perhaps the best time-to do so! This resource, Improving Turf in the Fall at https://go.unl.edu/rz9z is a great one to walk you through renovation depending on your situation. Some lawns can be easily improved by adding fertilizer this fall and/or overseeding. Some may need total renovation, which starts with a glyphosate (Roundup application) followed by waiting at least a week to then prepare the soil for planting.
Multiple ears on the same ear shank (with husk tissue on left and husked on right). Doesn’t appear to be impacting main ear in most fields I’ve seen these in. And, this is occurring on primary ear nodes and within fields (not just in endrows or in lower population areas).
Japanese Beetles: Areas of the State have seen Japanese beetles for a few weeks. They’ve shown up strong in the York/Seward county area this past week with the number of calls I’ve received.
Unfortunately they cause two problems. The larvae are grubs that can impact our lawns. The adult beetle is ½” in length with a metallic green head and white ‘tufts’ that look like spots on its abdomen. Adults emerge from grassy areas like lawns, ditches, and even fields; however, they don’t emerge at the same time. They emerge over a 4-6 week period beginning in late June and last for around 4-6 weeks. There’s one generation per year. Adult beetles feed, mate, and lay eggs in lawns and grassy areas. The eggs hatch 10-14 days later into grub larvae and feed on turf and grassy areas in the August time-frame. They also over-winter in turf and grassy areas.
Adults feed on 300 plant species, but their favorites are ones that are in many of our
landscapes (roses, cannas, marigolds, grapes, Virginia creeper, and trees such as lindens, birch, Japanese and Norway maples, cherry, plum, peach, American elm). They also feed on soybean and corn crops. They love hot weather and full sun and feed on leaf tissue during the day (leaf tissue will look skeletonized or lacy and turn brown). Trees may be severely impacted with browning occurring from the top to bottom. Thankfully healthy trees will re-leaf next year since the underlying twigs and branches aren’t damaged-even if the entire canopy is impacted this year. It’s not recommended to remove branches or trees.
DO NOT use Japanese beetle traps!!! Research shows they attract beetles to the landscape and many homeowners I’ve talked with will attest to this!
Beetle Control: Wait till dusk (7-9 p.m.) before trying to control beetles as they are less
active then and to reduce impact to pollinators. Organic means include hand-removing beetles by knocking them into soapy water. You can also spray trees with water to knock them down to the ground and then drown in soapy water. This takes diligence over many days. With heavy beetle infestations, it’s not uncommon to literally have scoop shovels full of the beetles when removing from trees. Neem and Pyola are two organic sprays that will protect for 3-7 days. Applying these products regularly (once per week) can also be effective as a repellent.
Japanese beetles often impact the same flowering plants that other pollinators visit. Use insecticide products correctly to avoid damage to pollinators. Avoid spraying insecticides on windy days or when pollinators are present (best to spray late in day near dusk) and be sure to read and follow all label instructions and harvest intervals (for cherries, plums, etc.). Conventional insecticides can provide 2 weeks of control: pyrethroid products like Tempo and Bayer Advanced Lawn & Garden Multi-Insect Killer (cyfluthrin) or Ortho Bug B Gone (bifenthrin). Sevin (carbaryl) is another option although more dangerous for bees.
Grub Control: Turf damage can be evident in Aug./Sept. Products that control common white grub can also provide control of Japanese beetle grubs and should be applied mid-to-late June. Dylox can be used as a rescue treatment if grub control is needed later on and no grub products were applied in the spring.
Next Year: Systemic products like imidacloprid can be used as a soil drench around plants (apply around Mother’s Day). These products can’t be used on Linden trees. You may also wish to swap out more susceptible plants for those less susceptible as you observe which plants they tend to impact most in your backyard.
Also seeing green June beetles and this shows the difference between them and Japanese beetles. Green June beetles don’t have the same impact on leaf damage. They do lay eggs in turf which become grubs as well.
Congratulations to all who graduated from college or high school the past few weeks! You’ve experienced much challenge, change, and loss. Good can come from difficulty! May this experience better equip you for the future! Also wish to congratulate and welcome three new team members to the York and Seward county offices! Tanya Crawford will begin as the 4-H Educator in York County May 18. Emily Hemphill began as the 4-H Assistant in Seward County May 1. Kara Kohel will begin as the new Learning Child Educator in Seward County June 1.
Crop Update: Grateful for the recovery experienced on many frost/freeze damaged crops throughout the State! The worst damage I saw on corn in this part of the State resulted in exposed leaf tissue dying with new growth coming out of the ground within 5 days. Soybeans fared well in the area to which I’m extra grateful with the large number of early planted soybean acres this year!
There’s been some talk about uneven emergence in some fields. Most really aren’t too bad, just worse in fields that were worked or extra cloddy. And most often, seedlings are still coming when digging in the gaps. They’re just behind most likely due to depth or soil moisture variation. You may also want to check out an article on Early Season Insects in this week’s CropWatch at cropwatch.unl.edu. Also seeing and hearing of ammonia burn to roots of corn seedlings, mostly in strip till situations, due to the dry conditions. An inch or two of rainfall or irrigation can help dilute the salt concentration in the root zone and allow for growth of roots to resume. I realize this doesn’t help those without irrigation and we keep praying for rain. In a 2009 trial at UNL South Central Ag Lab near Clay Center, Dr. Richard Ferguson documented those plants being shorter in stature and appearing to have a purple color early in the growing season before later recovering.
For those asking about replanting, we have two articles to aid in decision making in this week’s CropWatch at cropwatch.unl.edu. I haven’t seen situations warranting this around here yet. It takes quite a stand loss. For example in corn, if there are 25,000 plants per acre and the field was initially planted on April 27 and you cannot replant until May 20, it would be better to leave your present stand, which has 95% yield potential, than to replant on May 20 when the yield potential for a stand of 30,000 would be 86%. Make sure you consider replant costs in your decision. Next week I’ll address thoughts on post applications to crops.
Lawn Update: As lawns grow, it’s important to not remove more than 1/3 of the height. During the spring and fall, cool season grasses such as bluegrass and fescue are also building their root reserves. Removing too much growth at once or continually mowing shorter than 3” puts more stress on the plant and doesn’t allow for as deep of roots for when the summer heat comes. UNL turf research found that lawns actually grow faster when they are scalped than when they are mowed at a taller height. So, if your lawn gets away from you like mine did last week, do your lawn a favor and raise your mowing height that one time and then go back to mowing at 3”.
Youth Learning Opportunities: There are a number of virtual and self-paced fun, learning opportunities for youth and families upcoming in the month of June! Many of the activities that were provided during the school year will be continuing with new sessions. You can check them all out at: https://4h.unl.edu/virtual-home-learning.
Building Better Babysitters Virtual Training: Additional childcare may be needed this summer. Babysitting is a big responsibility and it’s not for everyone. Youth ages 11 and up who are interested in building skills as a babysitter may be interested Nebraska Extension’s state-wide virtual babysitting training. Register by going to https://cvent.me/d4gWeD.
Adding some pics on frost recovery:
Happy Spring! With warmer weather forecasted the next few weeks, it’s a great time to get outdoors! Raking leaves from lawns is a great activity this time of year for the whole family. You can also overseed bare areas of lawns right now. Don’t remove leaves or mulch from landscape beds yet. Leaves and dead tops of plants protect the plants and keep them dormant as long as possible. Warm sunny weather causes plants to break dormancy early and they become more susceptible to cold temperatures. If you’ve already cleaned up landscape beds, be prepared to cover plants again in the event of cold weather. If you have frosted tulip/daffodil foliage like mine, just leave them be for now.
Even though grass is greening up, it’s too early to apply fertilizers (ideally not till sometime in May). Mowing isn’t needed until after the grass begins to grow and requires mowing. Then maintain a mowing height of 3 to 3.5″ season-long. Pre-emergence herbicides targeted at controlling crabgrass and other warm season annual weeds shouldn’t be applied until soil temperatures consistently reach 50°F. It’s still too early. Soil temps can be found at: https://cropwatch.unl.edu/tags/soil-temperature
Wild/Bur Cucumber: In wet seasons like last year, wild and bur cucumber were seen overtaking windbreaks. These are fast growing, warm season annual vines. They die each fall and come back from seed which germinate and begin growth typically in May. Vines can be cut at the base if there’s only a few of them this spring. Many asked about chemical treatments last year. A pre-emergent control option for large shelterbelts is Simazine (Princep 4L) to kill weed seeds as they germinate. Don’t apply more than 4 qt. Princep 4L per acre (4 lb. a.i./A) per calendar year. Don’t apply more than twice per calendar year.
Renovating Windbreaks: Do you have a windbreak that has several dead or dying trees in it? Steve Karloff and Jay Seaton, District Foresters, shared to think 15-20 years down the road. What would be your goals for the windbreak (wind/snow protection; bloom time; fruit, nut, wood; wildlife/pollinator habitat, etc.)? Each situation will be unique, so these tips won’t apply to each one. Determine whether you’d like to remove the entire existing windbreak or do a partial clearing over time. For those choosing a partial clearing, they suggest to consider leaving the north and west rows and removing the south and east side for sunlight, establishment, and protection purposes. Stumps can be left (unless Scotch or Austrian pine), or can be removed. A stump treatment listed in the UNL Weed Guide is 2 qts of low vol 2,4-D per 10 gallons of diesel. Apply to point of runoff. Don’t use Tordon especially if you’re cutting out and stump treating elm or hackberry trees that get intermingled in trees you wish to save as the Tordon can affect the roots of those trees too. If existing trees, such as pines, have been trimmed up due to dead branches but the remainder of the trees are ok, one could simply consider adding a row of shrubs to cut down on wind.
Also, think about diversifying species based on one’s goals to ensure the windbreak isn’t eliminated due to pest problems. That’s something we’ve unfortunately had to deal with regarding Scotch and Austrian pines due to pine wilt. Conifer specie options include: cedar (most hardy), Ponderosa pine, and Norway and blue spruce. Shrubs include viburnums and hazelnuts; however, there are numerous species to consider depending on goals. Consider 3-5 rows as optimal with 1-2 rows as conifers, 1 row of hardwoods or tall conifers, and 1-2 rows of dense shrubs. However, there’s not always that kind of room available and that may not fit one’s goals. It’s helpful to stagger plant the trees in each row and the gaps can be filled with shrubs or the shrubs can be planted in one row. Next week I’ll share more on site preparation considerations.
As I reflect, it was a hard week for many of you in our farming community with the weather and harvest delays. Many of us would say the challenges of 2019 actually started in the fall of 2018. From that perspective, it’s been an extra hard year! As we continue with a delayed harvest, I’m truly hoping the fall of 2019 doesn’t result in an extra challenging 2020 as well. I’m sure that’s a hope for us all!
It’s amazing how something as simple as the sun shining or incredible sunrises on then dreary, drizzly days lifted my spirits and the spirits of many of you I spoke or texted with this past week. For those who receive my email newsletter, you’ve seen me share each week a set of tips to consider for help in relieving stress/changing current mindset based on how much time you have in the day. And, some of you have rightfully put it back on me when I’ve needed a mindset change! While you may not want to take 30 minutes or even 10 minutes, we all have 2 minutes. So, my challenge for all of us is utilize one of the following tips for two minutes or use something else that works for you each day this week to change our mindset/lift our spirits when needed. Two minute tips (Adapted from: Gilbert Parra, PhD; Holly Hatton-Bowers, PhD, and Carrie Gottschalk, LMHP, MS): Breathe; Stretch; Laugh; Doodle; Acknowledge one of your accomplishments; Say no to a new responsibility; Look out the window (or go outside); (adapted) Faith based prayer. Please go to jenreesources.com for the full list.
Soybean Cyst Nematode (SCN) Sampling: With the increase in sudden death syndrome this year, several have asked for soybean cyst nematode sampling bags (as the two diseases are synergistic with each other). Free sampling is via the Nebraska Soybean Board through your soybean checkoff dollars. Sampling bags can be obtained from your local Extension Office or call 402-472-2559 to obtain bags. Crop consultants should contact Extension Plant Pathology directly (402-472-2559) for larger numbers of sample bags. Samples should be done for areas 40 acres or less (less is better). If you had areas with higher SDS this past year or places where yield maps showed lower yields, plan to take a sample from those areas of the field. Also take a sample from a good yielding area of your field for comparison. Take around 20 cores 6 to 8” deep. If you or an agronomist is taking soil samples, taking a few extra cores will allow for part of the sample to be sent in for fertilizer recommendations and the other part for SCN. Make sure to thoroughly mix the cores collected before transferring to sample bags. If you take them from a soybean field, taking the sample a few inches off the old soybean row may provide the highest potential numbers if SCN is present in the field. However, SCN samples can be taken from corn or sorghum fields as well to help inform decisions if rotating to soybean next year. Other places in fields which may first show SCN include: low areas where water drains after rain; along a stream that periodically floods; along fence lines; field entryways or driveways as that’s the first place equipment enters from other fields. Anything that moves soil will move SCN.
Lawn Weed Control: Now is an excellent time for weed control in lawns, especially for dandelions, clover, ground ivy, and plantain. This is because carbohydrates are being transferred to the roots of perennial weeds and thus allows for the chemical to move to the roots as well. If using granular products that contain weed killer, they’re best applied on mornings with heavy dew and no rain in the forecast for 24 hours (however, read the herbicide label). Most herbicides labeled for use around the yard will contain 2,4-D and/or dicamba. I’m often asked for names but this is not an exhaustive list and not intended to exclude anything available (2,4-D, dicamba, Weed B Gon, Trimec Plus, Trimec Classic).
*End of News Column.
- Acknowledge one of your accomplishments
- Say no to a new responsibility
- Look out the window
- (adapted) Faith based prayer
- Listen to music
- Have a cleansing cry
- Chat with a co-worker, friend, or family member
- Sing out loud
- Jot down dreams
- Step outside for fresh air
- Go for a brief walk
- Enjoy a snack or make a cup of coffee/tea
- (adapted) Read faith-based devotional
- Evaluate your day, Write in a journal
- Call a friend
- (adapted) Meditate, Prayer, Devotional
- Tidy your work area
- Assess your self-care
- Draw a picture
- Listen to soothing sounds/music
- Read a magazine
Perhaps it was the hard winter, but I’m finding the flowering trees to be exceptionally pretty this year! Corn and even some soybean went into the ground this past week too. In last week’s column I shared regarding planting considerations yet would still encourage growers to keep considering your local field conditions before planting. You’re hearing some of these same things from both Extension and Industry partners and we realize field situations differ. We keep repeating these things to provide reassurance when you’re questioning decisions. We’ve already seen problems with anhydrous application in too wet of conditions in some fields. We’ve already seen some situations that were too wet when corn was planted leading to problems with compaction, depth issues, and not closing seed vee’s. With the cold snap, it’s important to consider soil temperatures (preferably around 50F or warmer for next 48 hours), soil moisture conditions, air temperatures for the next 48 hours, potential for cold rain, and cold tolerance of seed. Soil temperatures are listed at http://go.unl.edu/soiltemp and I would also encourage you to check your own particular field conditions. Last week, I was finding soil temperatures in local field conditions to be cooler than what was being reported from high plains regional climate center. If you don’t have a soil temperature thermometer, you can do this with a meat thermometer (and just dedicate it for field use).
I can appreciate the added concern and stress with this week’s forecast. There’s several planting-related articles in this week’s CropWatch at http://cropwatch.unl.edu. Two really helpful articles from Roger Elmore share on corn planting windows where he used USDA NASS data to show Nebraska data and also shared how other states throughout the Corn Belt have found similar results regarding planting windows. The key point is there’s a planting window between mid-April to mid-May within which optimum yields are usually obtained. After this period, yields decrease rapidly. So there’s still time and the planting conditions play a role in determining final yield by getting that seed off to a good start. You also keep hearing me talk about planting soybean early. Even as early as you can in May is better than mid to late May for higher yields if that works for your situation.
Browning Evergreen Trees and Shrubs: This past winter was hard on many things. When it comes to evergreen trees, the deep frost line and extreme cold led to the inability for transpiring trees to uptake moisture. This resulted in needles appearing brown and looking dead, particularly on the north and sometimes west sides of trees. I’m seeing this particularly on junipers, cedars, arborvitae, white pines, and some spruce. We’d recommend waiting till June before pruning any dead portions out or removing any trees/shrubs to see what happens with new growth.
Rhizosphaera Needle Cast in Spruce has been really bad the past few years. If you’re seeing spruce needles on lower parts of the tree turning yellow/reddish-purple/brown, then this disease may be the problem. The fungus continues moving upward on the tree. Affected needles are prematurely cast from the tree. Above average moisture during the growing season in parts of the State led to an increasing number of spruces affected by the Rhizosphaera fungus. What’s interesting is that the fungus infects the needles in spring but the symptoms often don’t appear till the following spring. One way to double check is to look for tiny black specks on the needles and on the twigs. The good news is that fungicide applications of chlorothalonil (Fungonil, Daconil, Bravo) or Bordeaux mixture in May can help when shoots are ½ to 2” in length! If we get frequent rains this growing season, applications can be repeated every 3-4 weeks.
Vegetable Planting Guide: Gary Zoubek had put together an excellent vegetable planting guide for the area which can be obtained at the Extension Office or at: https://go.unl.edu/d7qk.
Spring Lawn Seedings: With the difficulty of this past year, many didn’t get dormant seedings on because of all the snow and typically lawn renovation in the spring is difficult because of the inability for applying crabgrass preventer to newly seeded areas. However, a new product has changed this! Scott’s Turf Builder Starter Food for New Grass contains mesotrione which provides PRE and POST control of weeds without affecting the new bluegrass or fescue seeding. We’d still recommending seeding as soon as possible or else wait till August. Tenacity is also a product containing mesotrione that works as a POST for emerged crabgrass, foxtail, and for those dealing with nimblewill (best to apply on troublesome grassy weeds up to 1” tall).
Rhubarb and Frost: For those impacted by frost/freeze this past weekend, if rhubarb leaves are not damaged too much and the stalks remain firm, it is still safe to eat. If the leaves are severely damaged or the stalks become soft or mushy, do not eat these stalks. Remove and discard them. New stalks can be harvested and eaten. Rhubarb often develops seedheads following cold temperatures, but this also does not affect eating quality of the stalks. Remove rhubarb seedheads and discard.
Planting Considerations: Everything we do at planting sets the stage for the rest of the year. We’re blessed to have equipment that can allow for many acres to be planted in a short amount of time. And, we have the ability to mess up a lot of acres in a short amount of time.
For soil conditions, it’s important that we’re not mudding in fertilizer and seed to avoid compaction and uneven emergence issues. Soil temperature information can be found at: https://go.unl.edu/soiltemp. It’s best to plant when soil temps are as close to 50°F as possible, check weather conditions for next 48 hours to hopefully maintain temps 50°F or higher, and avoid saturated soil conditions. If planting a few degrees less than 50°F, make sure to check with seed dealers on more cold-tolerant seed and only do so if the forecast is calling for warm temperatures the next few days that would also help increase soil temperatures. Once planted, corn seeds need a 48-hour window and soybeans need a 24-hour window when the soil temperature at planting depth does not drop much below 50°F. Otherwise chilling injury is possible.
With the variability of weather each spring, we perhaps need to shift our focus from “calendar dates” to “planting windows”. The optimum planting date for corn may not be in April every year. Research from Iowa State found optimum planting date windows to obtain at least 98% yield potential range from April 15-May 9 for northwest and central Iowa; from April 17 to May 8 for southwest Iowa; and from April 12-30 for north central and northeast Iowa. To achieve at least 95% yield potential, those ranges extend from April 15 to May 18 for northwest and central Iowa; from April 12 to May 13 for southwest and southeast Iowa; and from April 12 to May 5 for north central and northeast Iowa. It’s not Nebraska data, but could be considerations for us for similar areas of Nebraska. And, while we don’t have a lot of data in Nebraska, one can use USDA ag statistic yields and I’ve also used the Hybrid Maize Model to show how yearly weather can impact optimum planting windows for best potential yield.
Planting soybean early is critical to maximizing yield. Beyond genetics, this is the primary way to increase soybean yield through numerous University studies in addition to grower-reported data. Because of this, an increasing number of growers are planting soybean earlier than corn or at least at the same time as planting corn. ‘Early’ is within reason, though. While we’ve had on-farm research fields and many growers’ fields planted from April 22 and after (in good field conditions), be aware that crop insurance date is April 25. We also recommend adding an insecticide + fungicide seed treatment when planting in April as we have no data without seed treatment in our planting date studies.
Planting depth is also key. Aim to get corn and soybean in the ground 1.5-2” deep. This is critical for correct root establishment in corn to avoid rootless corn syndrome. While not as critical regarding root establishment for soybean, our UNL research showed lowest yields when soybean was planted 1.25” or less or 2.25” or greater with the highest yield at 1.75” deep. This is most likely because moisture and temperature were buffered, particularly when soybean was planted early. It’s important to get out and check seeding depth for all planter units within every field. Even with monitors showing down force and seeding depth, it’s still important to check. I’ve seen how adjusting down force can lift up planter ends resulting in shallow planting in the outside rows, particularly with center-fill planters. Results of improper/uneven planting depth can be seen all season long and may affect yields. While this takes time, you’ll be glad you caught any issues before too many acres are planted incorrectly!
For corn seeding rates, it’s best to check with your local seed dealer as all our research shows that optimal corn population varies by hybrid. However for soybean, our recommendation after 12 years of combined on-farm research studies continues to be: plant 120,000 seeds/acre, aim for a final plant stand of 100,000 plants/acre and you’ll save a little over $10/acre without reducing yields. If that’s too scary, try reducing your populations to 140,000 seeds/acre or try testing it for yourself via on-farm research! Please contact me if you’re interested in that. We have an article on our soybean seeding rate data in this week’s CropWatch at http://cropwatch.unl.edu.
Lawn Crabgrass Preventer and Fertilizer Application: Crabgrass is a warm season grass and needs soil temperatures to reach 55 degrees F for a few consecutive days to germinate. It doesn’t all germinate at once, thus the potential for a second flush in the summer. The targeted window to apply pre-emergence herbicides for crabgrass in eastern Nebraska is April 20 to May 5. Keep in mind that the product needs to move into the soil within 3 days or it will start breaking down due to sunlight exposure. You may also consider applying your crabgrass preventer with first lawn fertilizer application around the beginning of May.
Happy Summer! June 20th marked the start of the summer season. Summer means a good time for cookouts, picnics, swimming, and grub control. Not exactly what you had in mind for summer fun? Knowing the pest and its habits can help keep you from spending all of your summer fun time dealing with grubs.
In the landscape, October is the month to water, control weeds, and plant bulbs, trees and shrubs. It is also the month to wait until after a freeze to cut back perennial plants and wait for the soil to freeze before covering tender plants with winter mulch. Kelly Feehan, UNL Extension Educator, provides the following information.
Sometimes people ask if trees and shrubs should be watered at this time of year since their leaves will soon drop off; and how late in the season lawns should be watered. As long as the soil is dry, go ahead and water. Plant roots continue to grow long after leaves drop off trees and shrubs and after grass stops growing. Roots, rhizomes and stolons can grow well into November and fall watering promotes this growth helping plants recover from summer stresses. Plant energy can be used for root growth during fall since energy is no longer needed for leaves, flowering or seed production. Roots continue to grow until soil temperatures drop below 40 degrees Fahrenheit with available moisture.
Water enough to moisten the soil to a depth of about eight to twelve inches for trees and shrubs and six inches for lawns. Keep in mind that a lack of oxygen due to a saturated soil is just as damaging to roots as a lack of water. Allow the soil to dry between watering.
Because roots continue to grow well into fall, September through October is a good time to plant deciduous trees and shrubs. For spring flowering bulbs, wait until soil temperatures drop to 60 degrees Fahrenheit to plant.
A common question asked about fall planting is if a starter fertilizer needs to be used at planting time. Starter fertilizers are high in phosphorous, a nutrient important to root production. The only way to know the answer to this question is to have a soil test taken. However, most landscape soils are high in phosphorous (P). Fall soils are often warm and dry which makes P more readily available. In most cases a starter fertilizer does not need to be used during fall planting.
More important is to plant at the correct depth. With bulbs, follow label directions for planting depth. It varies depending on bulb size. Some recommendations say to plant about one to two inches deeper than recommended. The opposite is true for trees and shrubs. Before planting trees, locate where the trunk flares out at the trunk base then plant at a depth so the flare is visible above ground. Do not loosen the soil beneath the root ball or the tree may settle and end up planted too deep. In heavier clay soils plant so the trunk taper is one to two inches above the ground.
October is the best time to control perennial broadleaf weeds like dandelions, ground ivy and clover. There is no ideal time during fall to apply lawn weed and feed products together. The best time to fall fertilize lawns is in early September and again in late October or early November. The best time to apply herbicides for lawn weeds is about mid-October before a hard freeze.
Weed control can be more effective and less herbicide will be applied where it is not needed by avoiding the use of combined weed and feed products during fall. One can achieve better weed coverage and control of established broadleaf weeds if the weeds are spot treated, typically with a liquid formulation of herbicide.
Here’s wishing you a great October of accomplishing landscaping projects!