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Producing Quality Forages with Winter Annuals Ted Probert
We are now beginning to experience some warmer weather and fields are greening up. Some of the first plants to start growing in spring are winter annuals. With that in mind it is time to begin making plans for utilization
and harvest of winter annuals that have been grown for forage production.
Popular winter annual forage crops grown in southern Missouri include rye, wheat, triticale and annual ryegrass. These crops are often utilized through fall and spring grazing but also work very well when harvested and stored in the form of hay, silage, or baleage. Due to the
fact that harvest of these crops is accomplished at a time when curing is difficult, silage or baleage are the preferred means of preservation. Winter annuals are capable of producing a feed source of high nutrient content with proper attention to harvest and storage practices. Considering the cost associated with planting, growing and harvesting these
crops, management for a high value, high quality feed should be a top priority for growers. Accomplishing the goal of producing high quality feed from winter annuals however, does take some effort and attention to detail. It
is not uncommon to see these forages harvested in a manner that produces less than desirable feed, feed that in
some cases may be difficult to utilize in livestock feeding programs. Obviously the goal should be to produce feed that will contribute positively to our animals’ nutritional needs. Once they break dormancy and begin to grow in the spring, winter annuals develop very rapidly to harvest stage. Striking a balance between optimal forage yield and
optimal feed quality will be accomplished only by harvesting in a fairly narrow window of plant development that occurs during a time span of only a few days. The following table details nutritional values of wheat silage when harvested at various stages of maturity (Chart adapted from MU G3260).
As can be seen in the chart winter annuals can provide feed of excellent quality if harvested at the correct stage. Based upon these values the recommended stage of harvest for small grains and annual ryegrass is in the boot
stage. Upon reaching the head stage they start to decline rapidly. Only a few days following heading both protein and net energy values fall drastically. Rye, triticale, and annual ryegrass will all follow a developmental curve similar to wheat. Quality tends to
decline more rapidly in rye and triticale however. Also rye will develop two to three weeks earlier in the season than
wheat. Wheat will still be of reasonable quality into the early head stage but rye and triticale will not if the feed is intended for dairy cattle or growing animals. Once small grains have advanced past early to mid-head (for rye and triticale, late boot to very early head) resulting feed will be a challenge to use in most ruminant diets. See the wheat
development scale below for a visual depiction of the proper stage for harvesting winter annual grasses. The target stage is 10-“boot”. While stage of harvest is very important in producing high quality feed, it is not the only factor that will have an influence on doing so. During most spring harvest seasons drying conditions will not allow time for forages to
dry down to moisture levels needed for baling dry hay.
Preservation of winter annuals will generally be more successful through making silage or baleage. Achieving proper wilting of forages before ensiling is very important to the quality of the resulting feed. For wrapped baleage moisture level should be 40-60% with 45-55% being ideal. Silage going into bags or pits can be a bit wetter – 55-65%
moisture. The goal in growing forages for livestock should be to produce feed that will meet the nutritional requirements of your animals. Winter annual grasses offer high potential for achieving this goal but attention to best harvest and storage practices will be critical to producing top quality
feeds. If you would like more information on growing, harvesting, or preserving winter annual forages contact your local extension office.
University of Missouri System, Lincoln University, U.S. Department of Agriculture & Local University Extension Councils
Cooperating
EQUAL OPPORTUNITY/ADA INSTUTIONS
Howell County Extension Center
217 Aid Avenue, West Plains, MO 65775 Phone 417-256-2391
extension.missouri.edu/howell
April 2015
South Central Missouri AG News
Sarah Kenyon, Agronomy Specialist, Ted Probert, Dairy Specialist,
Bob Schultheis, Natural Resource Engineer
Randy Wiedmeier, Livestock Specialist Stacy Hambelton, Agriculture Economist
Growth stage NDF ADF Crude
Protein
NEl
Emerging 46.10 25.08 30.90 .80
Early vegetative 46.15 28.37 26.30 .83
Late vegetative 46.63 28.76 22.45 .83
Boot 53.10 32.25 20.87 .76
Early head 56.73 37.24 15.31 .68
Mid-head 61.45 39.01 11.26 .61
Late head 67.99 43.42 10.27 .46
Milk stage 60.30 39.97 8.99 .49
Dough stage 58.77 38.73 8.49 .56
Ripe seed 59.79 34.05 6.78 .55
Fetal Programming II Randy Wiedmeier
In the last (March) issue I summarized a couple of university studies that indicated that the nutritional management of cows during gestation can affect the
development of fetal calves by in some way “tweaking” the gene expression of the calf. In my former life I studied low-quality forage
utilization in cattle mainly, with a few studies using sheep and horses. After many of these studies I noticed a fair amount of variation in the utilization of these forages between individual animals. Some cattle would perform quite well on these forages. Others would fall apart. This was surprising since the cattle assigned to these studies were from the ag experiment station herd and therefore
had similar management and genetics. So my students and I set out to discover some of the sources of this variation. We first decided to try to measure the heritability of low-quality forage utilization in cattle and estimated it to be only 20%. This meant that only 20% of the variability was
likely do to genetics. It also meant that 80% of the
variation was due to environmental factors. So we decided to concentrate on environmental factors. One of these factors that we discovered had a major impact on the utilization of these forages was what a calf learns to eat from its mother. We found that if calves had access to low-quality forages shortly after birth while their mothers were consuming these forages they showed a substantial
improvement in the utilization of these forages later as mature animals compared to cattle that had so such exposure. Sometimes there was as much as 5 years between being initially exposed to these forages as a suckling calf and when they were re-exposed as mature cows. After this discovery we decided to “back it up a
step” and see if feeding low-quality forages to gestating
cows would affect the utilization of these forages by their calves. To reduce the genetic variation of the cows we selected for this study we used full sisters and half- sisters. All of the cows were bred to the same bull so all of the resultant calves had an extremely high genetic relationship.
During gestation half of the cows were fed a diet composed of ammoniated wheat straw supplemented with a small amount of wheat middlings. The other half received a diet of average-quality grass hay supplemented with a small amount of ground barley. Even though the two diets contained the same amount of energy and protein, the ammoniated straw diet contained twice the fiber (NDF). We
did not want the calves to be exposed to ammoniated straw shortly after birth so immediately prior to parturition all cows were fed mixed grass-alfalfa hay. All cow-calf pairs grazed in common on flood meadow pastures during the
grazing season. After weaning the calves were placed in individual pens and all calves were fed the ammoniated straw diet. Intake and digestibility were measured after an
appropriate adaptation period. This measurement was taken again when the calves were approximately 18 months of age. We found that calves whose mothers were fed the ammoniated straw diet during gestation consumed more ammoniated straw and digested more of it compared to
calves whose mothers were fed the grass hay diet during gestation. Although the magnitude of change was rather small ( 6.8 versus 6.1 lbs. of digestible dry matter/day), indeed a high-fiber diet fed to mother cows during gestation had improved the utilization of fiber by their offspring. If I had had the time and funding, it would have been
interesting to try to determine the anatomical/physiological adjustments made in these calves that allowed them to improve their utilization of low-quality forages.
Spring Weed Control Sarah Kenyon
Henbit and Chickweed should be sprayed very soon; these plants are flowering, a timely herbicide application can reduce the amount of seeds produced. Herbicides containing the active ingredients dicamba and 2,4-D will give good results (Banvel/Clarity mixed with 2,4-D or
HiDep).
Poison hemlock should be controlled before the plant forms an upright stem. Use Tordon 22K (1 pt/A) or Grazon
P+D (1 qt/A) before it bolts in the early spring.
Thistles should be sprayed during the rosette stage. Cimarron, Cimarron Max, Banvel, Grazon P+D, Milestone,
GrazonNext, and Tordon 22K have provided good results. If application is made during the rosette stage of growth, 2,4-D gives good control but offers no residual activity. Do not
spray Musk Thistles (left) after flower buds begin to develop. At that stage, leave control to the musk thistle weevil. Bull Thistle (right) is becoming an increasing
problem and can be identified by the presence of hairs on the leaves.
Spotted Knapweed is the biggest weed problem in our area. Use Milestone (5-7 oz/A), Tordon 22K (1 pt/A) or
Grazon (2 qt/A) in the rosette to bud stage. Treat before it gets 12” tall.
Protect Yourself from Hearing Loss Bob Schultheis
Farm workers experience one of the highest rates of hearing loss, caused in part by the loud noises generated by tractors, grinders, choppers, combines, grain dryers,
conveyors, chain saws and shotguns, to name a few. Unless noise-control measures are taken, prolonged exposure to excessive noise can cause permanent hearing loss.
Hearing loss can also affect anyone operating lawn mowers, carpentry or metalworking saws, or even wearing stereo headphones set to a loud volume. The extent of hearing loss will depend on the intensity, frequency, and duration of the noise. Intensity is the loudness of a sound and measured in decibels or "dBA". Normal conversation measures at 60
dBA, a tractor or power saw measures at 85-100 dBA, and a chainsaw measures at 110-120 dBA. Frequency is the pressure of the sound and is measured in hertz or "Hz". The human voice has a range of about 200 to 4000 Hz. Noise-induced hearing loss first
causes the loss of ability to hear sounds at 4000 Hz. Loss
then proceeds down into the 500 to 3000 Hz frequencies, which is the range crucial to understanding conversation. Duration is the amount of time a person is exposed to a sound level. For every five-decibel increase above 90 dBA, the permissible exposure time is reduced by half (see Table 1). The average person can be exposed to a sound source producing 90 dBA for a maximum of eight
hours per day without hearing damage. If the sound level is at 110 dBA, then the maximum exposure drops to 30 minutes per day.
Your ears will provide two warning signs of
overexposure to noise--temporary threshold shift (TTS) and ringing in the ears (tinnitis). Your ears will recover to some extent in 12 to 14 hours if you remove the noise source, but any amount of hearing that does not return becomes a
permanent hearing loss. Noise-induced hearing loss cannot be reversed, and a hearing aid does little good, so prevention is by far the best treatment.
To reduce noise levels, keep machine parts well-lubricated, replace worn or unbalanced parts that cause vibration, and use high-quality mufflers on engine-powered equipment. Wear acoustic ear muffs or pre-formed rubber or foam ear plugs. Ear protective devices block out only those sounds that are dangerous to hearing, and can
reduce noise levels by 15 to 40 decibels. Cotton is not effective at reducing noise exposure. Finally, adjust work schedules, when practical, so that workers do not exceed the allowable daily exposure limit to a high noise source.
As a rule of thumb, if you need to raise your voice to be heard an arm’s length away, the noise is loud enough
to damage your hearing.
To learn more about the dangers of noise and how to protect yourself and your family, ask for MU Guide G1962 Noise: The Invisible Hazard, from your county
University of Missouri Extension Center, or get it on the Web at http://extension.missouri.edu/p/g1962. If you have questions on this topic or other engineering concerns, you can reach me at the Webster County Extension Center in Marshfield by phone at 417-859-2044, by email at [email protected], or go to our website at extension.missouri.edu/webster.
Upcoming Events
April 23—Beef and Forage Conference, West Plains Have you ever wondered if some animals naturally perform better on Kentucky-31 compared to other ones? Dr. Rob Kallenbach will present current research findings
involved with this topic, titled “Tolerance of cattle to tall fescue toxicosis: Is it real”. Dr. Gene Stevens will also present information a research trial that was conducted on Ian Kurtz’s farm near Pomona. Information presented will explain building soil potassium and phosphorus levels in fescue hay fields. The conference will be held at the West Plains Civic
Center, Magnolia Room. Registration will start at 5:30 pm, with the meal and presentations to follow. Pre-paid registration is required with a fee of $15 per person. Registration includes meal and reference materials. To pre-register or for more information, please contact the Howell County Extension Center at 417-256-2391.
Table 1. Permissible noise exposure scale, based on OSHA Noise Standard
Duration, hours per day
Sound level, dBA
8 90
4 95
2 100
1 105
1/2 110
1/4 or less 115
Hearing Loss Indicators
Do you have trouble hearing when two or
more people are talking?
Do you have trouble hearing over the
telephone?
Do others complain you turn the TV
volume up too high?
Do you strain to understand conversations?
Do you have trouble hearing if the
background is noisy?
Do you frequently ask people to repeat
themselves?
Do you think people mumble frequently?
Managing Alfalfa Weevil Sarah Kenyon
Adult weevils often lay eggs inside alfalfa stems during warm days in the fall,
winter and spring. Alfalfa weevil larvae grow through four stages (instars). The eggs hatch
from early to late spring with the first stage crawling to the top of alfalfa stems to feed inside
the plant terminals. By the time the third and fourth stages feed on foliage outside the
terminal, a large amount of foliage can be consumed. Walk alfalfa fields as early as late March for signs of leaf feeding. Most years the
feeding gets progressively worse throughout April. The most effective scouting technique is
to collect ten alfalfa stems in each of five locations around the field and tap them into a white
bucket. Be sure to gently handle the stems so larvae don’t fall to the ground before getting
them to the bucket. Scissors can be helpful to accomplish this. Determine the average
number of larvae per stem. The economic threshold for alfalfa weevils is an average of one
or more larvae per stem and 30 percent or more of the plant terminals show feeding damage.
If the field’s infestation is greater than this, it may be time to start spraying.
Early harvest is an option for management of weevils compared to spraying insecticides. Remember, that it is best for the crop to
not harvest earlier than 7-10 days prior to the normal growth stage of 1/10th bloom. This harvest could be done by hay cutting or by grazing.
Missouri research has found that 98 percent of the weevils can be reduced with mechanical harvest and 90 percent can be reduced by
grazing cattle. If grazing, be cautious of bloat from wet foliage and damage to the crowns from trampling during wet conditions.
Choose labeled insecticides if threshold levels are reached. See the chart below for registered products in Missouri. It’s best to use
a lot of water in the spray mix for ground applications, with 20 gallons per acre considered optimum. Pay close attention to the preharvest
intervals. Outdoor air temperature needs to be at least 50 degrees F for optimum results; the temperature needs to remain above 50 until the
chemical dries on the plant, usually 2-4 hours after application. Steward can be effective at cooler temperatures.
This chart is a general guide. Be sure to read and follow all label directions, precautions and restrictions of the product you purchase.
* Designated a restricted use product.
Chemical name Common name Rate Preharvest Interval
Beta-cyfluthrin *Baythroid XL 1.6 to 2.8 fl oz/acre 7 days
Lambda-cyhalothrin + chlorantraniliprole *Besiege 6.0 to 10.0 fl oz 1 day forage; 7 day hay
Chlorpyrifos + gamma cyhalothrin *Cobalt Advanced 19 to 38 fl oz/acre 7-14 days
Chlorpyrifos + gamma cyhalothrin *Cobalt 19 to 38 fl oz/acre 7-14 days
Dimethoate Dimethoate/Dimate see specific label 10 days
Phosmet Imidan 70W 1 to 1 1/3 lb/acre 7 days
Methomyl *Lannate 0.9 fl oz/acre 7 days
Chlorpyrifos *Lorsban Advanced 1 to 2 pts/acre 7 - 21 days
Chlorpyrifos *Lorsban 4E 1 to 2 pts/acre 7 - 21 days
Chlopyrifos *numerous products see specific labels
Zeta-cypermethrin *Mustang Maxx 2.24 to 4.0 fl oz/
acre 3 days
Permethrin *numerous products see specific label 7 - 14 days
Gamma-cyhalothrin *Proaxis 1.92 to 3.2 fl oz/
acre 1 day forage; 7 day hay
Zeta-cypermethrin *Respect EC 2.24 to 4.0 fl oz/
acre 3 days
Carbaryl Sevin 4F 1 qt/acre 7 days
Carbaryl Sevin XLR Plus 1 qt/acre 7 days
Zeta-cypermethrin + chlorpyrifos *Stallion 5.0 to 11.75 fl oz 7 days
Indoxacarb *Steward 1.25 EC 4 to 11.3 fl oz/acre 7 days
Cyfuthrin *Tombstone Helios 1.6 to 2.8 fl oz/acre 7 days forage/hay
Lambda-cyhalothrin + chlorantraniliprole *Volian Xpress 6.0 to 9.0 fl oz 1 day forage; 7 day hay
Lambda-cyhalothrin *Warrior 1 CS 1.92 to 3.2 fl oz/
acre 1 day forage
Lambda-cyhalothrin *Numerous products see specific labels 1 day forage; 7 days hay