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2. Weed Control Basics
By Paul Hay, UNL Extension Educator
This is Botany 101, English 101 and Chemistry 101 in laymen's terms for homeowner's lawn weed control. I promise to use words longer than four letters, but am forced to use a few chemical names.
Botany 101 - If you have some idea how the weed grows and how the weed killer works it will help you get better control. As an example dandelions are a perennial weed (they live many years). Dandelions store energy in the fall in the root in order to be able to flower and produce seed quickly in the spring. Killing dandelions in October-November or even December will mean a yellow-less lawn in the spring.
Henbit, a winter annual weed that germinates in the fall, gives us a spectacular purple display as we drive the country side in late April. In lawns, grass is the best way to control henbit. If you have a solid cover of henbit in the lawn, it means your grass is very thin or non-existent. Either overseed the area and care for the new grass or work up the area and seed new grass. Don't forget to think about why the grass was thin in the first place. If there is a problem, the weeds will likely reoccur and until the underlying problem is solved no amount of seed or weed killer will cure the henbit invasion.
Crabgrass, foxtail, barnyardgrass and other summer annual grasses germinate in late spring when soil temperatures top 60 degrees. This is usually May 1 in Southeast Nebraska and a few days later in the north. Pre-emergent crabgrass control materials should be applied just ahead of this in the last week of April or first few days of May. A second application of pre-emergent in early to mid June can bolster late season crabgrass control and help in spurge control.
Spurge is a summer annual broadleaf weed with milky sap which emerges in late June and July and grows up and over the grass. Application of lawn fertilizer and pre-emergent crabgrass killers in March or early April can be quite a problem. Early fertilization gives lots of top growth, roots are developing slowly, summer heat starts to stress the grass and the pre-emergent material fades early giving an opportunity for crabgrass to break the system.
English 101 - Take the time to read the label on all fertilizer and weed control materials. When it says "control" on the label that means 85% or higher kill rate. When it says "suppression" it means the weeds get sick but do not die.
Be sure to read about potential adverse effects, which leads us to Chemistry 101. A very common and quite safe weed killer for broadleaf weeds, like dandelions, is 2,4-D. There are several formulations and other chemicals are often mixed with 2,4-D. A common mistake often made by farmers and acreage owners is to use 2,4-D LV ester instead of 2,4-D amine on their lawns. This can result in damage to trees, flowers and shrubs which is largely avoided with 2,4-D amine. Homeowners should check the chemical ingredient section of the label and make sure that among all this gibberish they see 2,4-D amine.
Hard to kill weeds like white clover, bindweed, and violet are better controlled by repeated treatments using minimum rates of herbicide products. Four minimum rate treatments spaced 3-4 weeks apart will do a better job than one maximum rate application.
Another common active ingredient in some lawn weed killers is dicamba. Trimec is one example of a material with this active ingrediant. With this product, make sure to read and follow label recommendations regarding application timing, rate, and warnings about potential damage to nearby flowers, trees, and shrubs. Products like this should be applied no more than twice per year, being careful to avoid contact with above ground foliage, and out of the root zone of sensitive plants and perennial flower beds. Avoid using weed killers with dicamba from June 1 until September 1 when there is increased risk of the product moving off target.
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3. Lawn Weed Control
By Kelly Feehan, UNL Extension Educator
Now is the best time to control some lawn weeds, but it’s a good time to just let others go for this year. Here’s a rundown on a few common weeds herbicides will control at this time of year and which ones they will not control.
Purple flowering henbit has been a common sight in home lawns and gardens the last few springs. As a winter annual, henbit blooms in early spring and usually goes to seed and dies by late June. If you haven't already made a herbicide application for henbit, now is the time.
Henbit is an annual that germinates and begins growth from seed in the fall or very early spring. It blooms in spring with prominent purple to pink flowers. It is a low growing plant with square stems and small, scalloped edged leaves.
In lawns, the same pre-emergent herbicides used to control crabgrass control will control henbit; but only if the product is applied just prior to seed germination in the fall. For Henbit, make an application the first week of September and a second application one month later.
Yellow nutsedge, often called watergrass, is a tough to control lawn weed. This is an erect plant with yellow-green, waxy leaf blades. Herbicides will not control nutsedge this late in the season. Controls, herbicide applications and hand-pulling, need to be used by the third week of June to be effective.
Manage herbicide did a good job of controlling nutsedge, but was difficult to find this past summer since the company quit producing it. The chemical in Manage (halosulfuron) is now sold as Sedgehammer which is available to homeowners. Plan on using Sedgehammer next June for nutsedge control.
September and October are excellent times for controlling broadleaf, perennial weeds such as dandelion, white clover, creeping Charlie, and wild violet. For the best control, spot treat the weeds with a liquid herbicides to increase leaf coverage while decreasing the overall amount of pesticide applied.
Herbicides containing 2,4-D or the combination herbicides containing more than one type of herbicide are good products to use for some weeds. Another good choice is Drive herbicide, which is available for homeowner use. This herbicide has a broad spectrum of control and will control both broadleaf and grassy weeds. It is even showing promise on control of wild violets.
Drive will also control crabgrass that is growing now, but this would amount to a revenge treatment and is not often recommended. Most crabgrass has already gone to seed and the annual plants will die this fall. Using preemergent herbicides applied in early May is still the most effective chemical control of crabgrass.
The sharp, spiny burs of sandburs and puncturevine ( Texas sandbur) make their presence quite noticeable in late summer. These are also annual weeds that have already gone to seed and the plants will soon die. Chemical control of sandburs and puncturevine needs to take place in late May or early June. Premergent herbicides containing pendimethalin are the products of choice for these prickly weeds.
For safe and effective weed control, always read and follow all label directions when applying pesticides. If weeds are a perennial problem in your lawn, evaluate why the turfgrass is not competing. If needed, change lawn care practices that will help increase turfgrass density and weed competitiveness.
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4. Now Is The Time For Weed Control In Pastures
By Gary Lesoing, UNL Extension Educator
The fall is a good time to take a look at your pastures to see if they may benefit from a herbicide application. If winter annuals or biennials are a problem in your pastures, a fall herbicide application in the rosette stage of growth is recommended. Herbicides should be applied after rains to actively growing weeds for best weed control. Weeds that fall into this category include field pennycress, horseweed or mare’s tail, henbit, common mullein, bull thistle and musk thistle.
Did you have musk thistles this year? If so, walk out in those infected areas this week. I'll bet you find many thistle seedlings. Most thistle seedlings this fall will be small, in a flat, rosette growth form, and they are very sensitive now to control with herbicides. So spray this fall and thistles will not be a big problem next year.
If your pasture has legumes, most herbicides will cause significant injury or kill most vegetation that comes in contact with the solution. Spot spraying weeds or areas with severe weed problems may be the best method of application if legumes are present. These areas could then be overseeded next winter or spring with a legume of choice. Red clover and Birdsfoot trefoil and alfalfa are legumes that can help forage quality in cool-season pastures.
Many pastures are also becoming infested with perennials and woody plants that reduce forage production and grazing capacity. Some of these species as well can be treated this fall and winter for control. Some of the perennial species in our area include asters, dandelion, curly dock, ironweed, and several species of thistles. Woody plants include multiflora rose, buckbrush, Osage orange (Hedge) and honey locust among others. Perennials will be susceptible in the fall when food reserves are moving down into the underground portions of the plant. For complete control of perennials and woody plants, multiple herbicide applications and cultural practices such as mowing and optimum soil fertility will be needed.
The use of herbicides without good cultural practices will usually give poor weed control. In areas where forage stands are sparse, reestablishment may be needed. Careful use of herbicides is important to reduce the potential of damage or injury to the forage crop. Many of the herbicides recommend application to woody species when grass is dormant, while others may require several applications for control.
For recommendations on the best herbicides to use on your property, call your local UNL Extension office. Be sure to read and follow label directions when using herbicides on pastureland.
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5. Watch Out For Sericea Lespedeza
By Gary Lesoing, UNL Extension Educator
A troublesome weed that is making its appearance in southeastern Nebraska is sericea lespedeza. It has been identified on several locations in southeastern Nebraska, and it seems to be on the increase. This plant has been identified on CRP land, along highways and in roadside ditches, in several pastures and even on some acreages. This is a perennial legume that is a noxious weed in Kansas and has taken over in several areas of Missouri as well. Sericea lespedeza was planted by some government agencies as cover and feed for wildlife and also for erosion control. Unfortunately it is a very invasive species and has taken over thousands of acres of rangeland in Kansas and a lot of public land and roadsides in Missouri.
This weed is just coming into Nebraska, so if we can keep it under control before it gets a foothold maybe it won’t be such a huge problem here. Sericea lespedeza can grow as tall as 4’ under good growing conditions. It is a coarse plant with a dense growth of leaves along its stems and branches. In the vegetative stage cattle will eat it, but as it matures it becomes unpalatable to cattle because of high tannin content. It is a very prolific seed producer as well. It is extremely competitive and it can crowd out desirable grasses and forbs.
If you have a weed growing on your property that you don’t know what it is and think it may be Sericea lespedeza, bring it into your local Extension or Weed District office so it can be positively identified. If it is Sericea lespedeza, now may be a good time for control. Products that contain the active ingredient metsulfuron are the most effective in the fall. For pastures, the University of Nebraska recommends Cimarron. Kansas State University recommends the use of Escort XP. In early summer PastureGard and Remedy, both of which contain the active ingredient triclopyr, are recommended for control. The best time to spray in the summer is when the plant is actively growing. Sericea lespedeza is on the watch list for weeds in Nebraska, so we really want to keep it from becoming established here.
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6. Effects of a Freeze on Forages
By Bruce Anderson, UNL Extension Specialist
When plants freeze, changes occur in their metabolism and composition that can poison livestock. But you can prevent problems.
Sorghum-related plants, like cane, sudangrass, shattercane, and milo can be highly toxic for a few days after frost. Freezing breaks plant cell membranes. This breakage allows the chemicals that form prussic acid to mix together and release this poisonous compound rapidly. Livestock eating recently frozen sorghum can get a sudden, high dose of prussic acid and potentially die. Fortunately, prussic acid soon turns into a gas and disappears into the air. So wait 3 to 5 days after a freeze before grazing sorghums; the chance of poisoning becomes much lower.
Freezing also slows down metabolism in all plants. This stress sometimes permits nitrates to accumulate in plants that are still growing, especially grasses like oats, millet, and sudangrass. This build-up usually isn't hazardous to grazing animals, but green chop or hay cut right after a freeze can be more dangerous.
Alfalfa reacts two ways to a hard freeze, down close to twenty degrees, cold enough to cause plants to wilt. Nitrate levels can increase, but rarely to hazardous levels. Freezing also makes alfalfa more likely to cause bloat for a few days after the frost. Then, several days later after plants begin to wilt or grow again, alfalfa becomes less likely to cause bloat. So waiting to graze alfalfa until well after a hard freeze is a good, safe management practice.
Frost causes important changes in forages so manage them carefully for safe feed.
For more information on this and other topics, visit:
UNL Veterinary Extension, http://vetext.unl.edu/index.shtml
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7. Natural-born Weed Eaters: Goats
Robin Foulk,USDA Natural Resource Conservation Service
Do you have a weed problem, but are unable or unwilling to apply herbicides to your weed problem? Maybe goats are the solution to your problem. Their natural diet preferences make them the perfect choice for weed control. They actually prefer weeds over grass! Goats eat up to two pounds of forage per day, including weeds like salt cedar, thistles, bindweed, knapweed, leafy spurge and Russian olives.
For more information about how goats can be used to assist weed control, visit:
Ewe4ic Ecological Services, http://www.goatapelli.com/
Controlling Leafy Spurge Using Goats and Sheep, http://www.ag.ndsu.edu/pubs/plantsci/hay/r1093w.htm
Weed Management for Small Acreages, http://www.ext.colostate.edu/Pubs/natres/03106.html
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8. Safety Group to Launch Initiative to Keep Farm Children Safer-
Their Slogan "It’s Easier to Bury a Tradition than a Child"
(Marshfield, WI) The Childhood Agricultural Safety Network, http://www.childagsafety.org, is a newly formed coalition of health and safety organizations across the nation. These groups have combined their efforts for the first time to bring a unified safety message to agricultural communities. The message is geared towards protecting children from preventable injuries.
Why is this important?
In the U.S., agriculture consistently ranks among the four deadliest jobs, along with mining, transportation and construction. According to the National Safety Council’s most recent report (2005), agriculture had the highest rate of worker deaths at 29.2/100,000 workers; compared to an average across all jobs of 3.5 deaths/100,000 workers. And agricultural workers suffered 90,000 disabling injuries that same year. Nearly all these deaths and injuries are preventable.
One of the main differences between agriculture and other industries is the presence of children in the worksite. Farming is typically a family business, where children are raised on the farm and participate in farming activities beginning at young ages. Annually, more than 100 children are killed and 26,000 seriously injured in farm-related events in the United States.
Over the years, a growing number of organizations have identified the seriousness of these statistics and have promoted farm safety, especially for children. Across the country, they have created local or regional marketing programs addressing safety issues in farming communities. Now one unifying coalition, The Childhood Agricultural Safety Network (CASN), speaks with one voice, advocating farm safety for children.
The Message
CASN takes a “tough love” approach, stating that it is never okay for a child younger than 12 years to be on a tractor. The group advocates that the earliest a child should be on a tractor is when they are old enough to take and pass tractor safety educational classes.
In many rural areas, having children ride on the tractor with parents, or grandparents, is considered part of the farming tradition. Some farm adults consider this "quality time" with the child. Children even just a couple years old are often seen riding on tractors with adults, either riding on the lap, sitting on a fender, or standing on the axle.
Unfortunately, this quality time can turn into a horrific experience quickly, with children falling from the tractor and being crushed by tires, caught under mowers or other pull behinds, with the child being killed or maimed for life. And the biggest tragedy of all is that these events are one hundred percent preventable.
CASN is taking the position as an advocate for the child on the farm. These safety advocates acknowledge that the message that children should never be on or near tractors may be unpopular or even upset parents and farm owners.
Bury A Tradition
Although advocating safety for children, the marketing message is meant for adults- It’s Easier to Bury a Tradition than a Child. Talking directly to the farming community, the goal is to change behaviors. Much like seat belt messages have helped reshape the usage of seat belts in cars, CASN is hoping that their message to keep children off of tractors will make people think of the consequences and realize that it is in the child’s best interests to follow this simple rule.
No one wants to bury their child.
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