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Out Croppings: Important crop news from the field!

Evaluating and Managing Alfalfa Stands for Winter Injury

Posted: April 22nd, 2013 by outcropn

Dr. Heather Darby UVM Extension Agronomist

 Introduction

Many conditions occurring in the fall, winter or spring can have an impact on the winter survival or injury of perennial forage stands, particularly alfalfa. Therefore it is important to assess stands early in the spring and explore your options for managing winter injury.

How to Diagnose Winter Injury

First and foremost it is most important to determine if your fields were impacted by the winter weather. The most obvious sign of winter injury are stands that are slow to green up in the spring. If other fields in your area are starting to grow and yours are still brown, those stands should be checked for injury or death. In addition to “slow green-up,” fields with uneven growth patterns may also indicate damage.

winter_kill_alfalfa3

The best way to diagnose damage is to examine the plant roots in a suspect field. To do this, walk diagonally across a field and at regular intervals (every 4 to 5 paces) dig up a shovelful of plants (4 to 6 inches deep) and examine their roots. The roots of each plant should be firm and the interior color should be white or cream colored. If the roots are soft and the interior yellow to brownish in color it most likely was winter-killed. winter_kill_alfalfa4For alfalfa, the majority of healthy crown buds should be white or pink and firm throughout the bud. It is important to try and inspect as many plants as possible to determine the percentage of the stand and/or areas of the field that are injured.

 

Options for Fields Moderately Affected by Winter Injury

Winter-injured stands will require different management practices than healthy stands if they are to stay in production. If winter injury is evident consider the following:

Allow alfalfa plants to mature longer than normal before cutting. This will help the plants rebuild needed energy for future production. For severely-impacted stands, allow plants to go to full bloom before taking a first cut and to the early flowering stage for subsequent harvests. Increasing the cutting height may also help stands recover (Cosgrove and Undersander, 2003). New shoots will be developing at the base of the injured plants and it is important to not remove these shoots, which would result in further detriment. Lastly, do not cut winter-injured stands late in the fall; this will allow them to build up more reserves before winter.

If a significant loss of alfalfa was seen in a predominant grass stand, then you could manage it for grass. This will work best if the grass species are dominated by tall-growing species such as reed canarygrass, orchardgrass, and/or timothy. If the grass is less than 10 inches tall, it may still be economical to apply 50 pounds of nitrogen per acre to boost yield and protein. If the grass stand consists mainly of a lower-yielding forage such as “June” grass (bluegrass) you may want to consider replanting.

If the alfalfa stand was only partially injured (25 to 50 %), interseeding with a quickgerminating forage crop in thin spots could provide additional production (Stauffer, 2009). Interseeding can be done with a grain drill. No-till application into existing sods will provide the best results. In the event a drill is unavailable broadcast seeding is an option but generally results in a less uniform stand. Species that could be considered for interseeding include clover (4-6 lbs/acre), orchardgrass (8-10 lbs/acre) or perennial ryegrass (8-10 lbs/acre). Remember that perennial ryegrass maybe a short-term option since it does not overwinter well in all areas of the Northeast. Alfalfa should not be reseeded into the stand due to autotoxicity issues. When dealing with winter-injured stands, it is particularly important to adequately fertilize and control for weed competition.

Options for Fields Severely Affected by Winter Injury

If your stand was over 50% winterkilled, you may want to consider replanting. Depending on your needs, there are several forage choices.

A small grain/field pea mixture could be a good choice if the forage is needed in early- to mid- summer. Early-planted small grains (60 lb/acre) such as oats, barley, or triticale with the addition of field peas (50 lb/acre) will be ready for harvest between late June and mid-July. Research from the University of Wisconsin has reported yields between 2.5 and 3.0 tons/acre and Relative Forage Quality (RFQ) of approximately 100-125 (Undersander, 2003). Small grain/pea mixes should be harvested when the small grain is at late boot stage.

Corn silage will be the best choice for optimizing full-season forage production. If corn silage is planted by the end of June it will normally outyield most other forages; however you risk lower quality forage. At these later dates (mid-June to early July) you may want to consider planting a summer annual. A few options include sorghum-sudangrass hybrids, sorghum -sudangrass hybrids enhanced with the Brown Mid Rib (BMR) gene, forage sorghum, sudangrass, and forage millets. Recommended seeding rates for these species vary considerably by forage type and range from 25 to 60 lbs per acre. These forages should be harvested when they reach approximately 30 inches. It is important to note that these crops need high temperatures to yield well and may not be the best choice if growers are experiencing cool to average temperatures. Studies conducted at the University of Wisconsin have reported summer annual yields between 2 and 6 tons/acre and RFV between 90 and 100 (Undersander and Lane, 2001).

There has been a lot of interest in growing sorghum-sudangrass enhanced with the BMR gene. The BMR gene has a characteristic of reduced lignin content, and hence tends to be highly digestible. The seed should be drilled ¼ to ½ inch deep at a rate of 50 lb/acre and fertilized the same as corn. Harvesting should take place after the grass is 30 inches tall or just before heading (Undersander and Lane, 2001). If planting is done by the first half of June, a second harvest can probably be made in September. Reports from Cornell University show that the forage quality of BMR sorghum-sudangrass can have a digestible neutral detergent fiber concentration (dNDF) of almost 70%and crude protein (CP) of up to 18% (Ketterings et al., 2002).

References and Citations


MILK PRICE PROTECTION FOR THE STATE’S DAIRIES OPENS THIS WEEK

Posted: August 27th, 2012 by outcropn

Vermont dairy farmers will once again have an opportunity to purchase federal insurance which protects the gross margin between low milk and high feed prices through the USDA’s Livestock Gross Margin for dairy cattle program.  UVM Extension’s agricultural economist, Bob Parsons, said that Vermont dairy farmers took full advantage of the program during prior sales periods, insuring over 6.8 million pounds of milk.  With feed prices at record highs, this insurance can help pay the bills and cover living expenses, says Parsons.

Due to higher than expected nationwide interest last fall, all the remaining funds for the program were committed.  However, an additional $2.5 million has been made available nationally by the USDA.

The sales period will open this Friday, August 31, and it is expected that the demand will quickly exceed the funds.  Farmers interested in purchasing Livestock Gross Margin insurance for dairy cattle should contact a crop insurance agent immediately.   For more information, call UVM Extension at 802-349-2966.

Impact of Dry Weather on Corn Growth and Development

Posted: August 20th, 2012 by outcropn

Dr. Heather Darby, UVM Extension Agronomist

Very low precipitation over the last few months has caused drought stress in isolated areas of the state. The dry weather can have an impact on corn growth and development. For many farms corn silage harvest will begin in the next few weeks partly due to an above average accumulation of growing degree-days (GDDs) and for some due to severe drought stress. The goal of this article is to describe the impact of drought on corn development and provide suggestions for managing drought-stricken silage.

Drought Impacted Corn in Grand Isle County

Impact of drought on corn pollination
Many producers have observed leaf rolling in their corn fields especially in fields where soil compaction is severe. Some of these fields are entering the critical pollination and fertilization period where any type of environmental stress will result in yield loss. About 2 weeks before silk emergence, corn enters the period of grain yield determination. Corn is the most sensitive to drought stress during this period. Continued wilting of the plant at this stage can decrease yield 3 to 4 percent per day. Inadequate plant water can also delay silk elongation and silks that do emerge may become non-receptive to pollen. Obviously this can result in poor pollination. During the silking and pollen shed period, severe stress may reduce yield up to 8 percent per day.

Impact of drought stress on grain-filling
Water stress during grain-filling reduces yield 2.0 to 6.0% with each day of stress.
Abortion of kernels during the first 2 weeks following pollination is common during drought. Kernels can also abort during blister and milk stages if there is severe drought stress. Once kernels have reached the dough stage of development, yield losses will occur mainly from reduced kernel test weight. Drought stress during dough and dent stages can lead to premature black layer formation in the kernels.

Impact of drought stress on corn nitrate levels
Drought conditions can cause nitrates to accumulate in corn plants. Under normal growing conditions, nitrates are quickly converted into plant proteins and other compounds. When plant growth is slowed or stopped, nitrates can accumulate in the plant. Rainfall following an extended dry period may cause an immediate increase in nitrates for 2 to 5 days until the plant can utilize the nitrates.

There are several strategies that can help reduce nitrate levels in drought-stressed plants. First, try to wait 3 to 5 days after an appreciable rain or long cloudy spell before harvesting crops. Since nitrates accumulate in the stalks, consider a higher cut height. Leaving 12-inch stubble in the field can reduce nitrates but would also reduce yields. Ensiling will also help to reduce nitrates by as much as 60 percent. Allow the forage to ferment for 4 weeks to allow for complete fermentation. Any suspect feed should be tested for nitrate levels before feeding. The silage can also be tested at harvest to determine if nitrates are a cause for concern.
Symptoms of acute nitrate poisoning in animals are related to the lack of oxygen in the tissues. These include muscular weakness, accelerated heart rate, difficult or rapid breathing, cyanosis, coma, and even death. Drop in milk production, abortion due to lack of oxygen getting to the fetus, poor performance and feed conversion are seen in chronic cases. The most critical factor influencing possible toxicity is the rate of nitrogen intake, which is affected by forage dry matter intake over a given time period. Feeding practices that regulate dry matter intake can be used to manage high nitrate forages. When stored forages contain more than 1,000 ppm NO3-N, intakes generally must be managed to avoid toxic effects (Table 1).

Source: Adams, et al. 1992. Prevention and Control of Nitrate Toxicity in Cattle. Taken From: From Harvest to Feed: Understanding Silage Management, by C.M. Jones, A.J. Heinrichs, G.W. Roth, and V.A. Ishler, Depts. Of Dairy and Animal Science and Crop and Soil Sciences, Penn State University

Lastly, high nitrates can also contribute to elevated levels of deadly silo gas. Silo gas is produced 4-5 days after silo filling. During this period the nitrates are converted to oxides of N. Nitrogen dioxide or NO2 is the most common and is a yellowish orange gas with a bleach-like odor. This gas is heavier than air and can form in the silo and then escape down the unloading chute into the barn, endangering humans and livestock. Exposure to silo gas can cause immediate death or severe lung injury due. To avoid exposure to silo gases, keep the door between the feed room and the barn closed, ventilate the silo by running the blower for at least 20 minutes before entering the silo and learn to recognize the bleach odor and yellow-orange color as signals of silo gas.
For more information on nitrate testing of forage please contact Dr. Heather Darby – (802) 524-6501 or Dr. Sid Bosworth – (802) 656-0478 at the University of Vermont Extension.

Armyworm Alert!

Posted: June 11th, 2012 by outcropn

An armyworm outbreak has been reported in New York. Western NY through the western edge of the Finger Lakes is where there is the most activity. Damage to grass hay, wheat, corn, pastures, and lawns has been reported for this area. Armyworm has also been found in the greater Albany area and most recently in Clinton county (NE NY).  Over the last week very low numbers have been observed in Northeastern, VT as well.

Please don’t panic, but do go out and scout your corn and grass fields for armyworms. When full grown, the caterpillars can be almost 1.5 inches long. The caterpillars are usually greenish or brownish, but can be almost black. The sides and back of the caterpillar have light colored stripes running along the body. The caterpillars normally feed at night and much damage can occur before they mature. The preferred foods are grasses including corn, grains, and timothy. They will feed on other plants if grasses are unavailable. Feeding will start on the lower leaves and move upwards. A large population can strip an entire field in just a few days. When the field is eaten they “march’ to adjacent fields. Corn fields that are minimum or no-tilled into grass sod or fields infested with grass weeds are most susceptible.  For more information on scouting and control options please contact Dr. Heather Darby at the University of Vermont Extension at (802) 524-6501.

Winter Spreading Ban Lifted

Posted: March 21st, 2012 by outcropn

20 March 2012

WINTER SPREADING BAN LIFTED

As a result of unusually warm and dry weather, lack of snow and projected weather forecast over the next few weeks the Agency of Agriculture, Food & Markets in agreement with the Agency of Natural Resources and Vermont Association of Conservation Districts is lifting the winter spreading ban that normally is in place until April 1st. According to Secretary Chuck Ross, “I am lifting the ban because I believe it will help farmers best manage their manure resources and is in the best interests of Vermont’s waterways.” David Mears, Commissioner of the Department of Environmental Conservation agreed stating “Current conditions are favorable for manure application. Taking advantage of good weather now may prevent application of manure later when conditions may not be as good.”
The manure spreading ban is a regulation that has been in place since 1995 under the Accepted Agricultural Practice rules. Vermont was a leading state in developing such a ban, however in recent years several other states have been considering or adopting the idea. Research has shown that manure applications on frozen ground can increase the runoff potential. Vermont chose to select a ban period from December 15th to April 1st each year to protect water quality; however the Agency has discretion with those dates to accommodate these exact types of circumstances.
Farmers are reminded that Vermont’s Accepted Agricultural Practices Rules and medium and large farm permit requirements apply as appropriate including:

  • Manure shall not be spread within 10 feet of the top of the bank of surface waters or within 25 feet at points of concentrated runoff on small farm operations
  • Medium and Large farms shall not spread manure within 25 feet of the top of the bank of surface waters
  • Manure shall not be applied in such a manner as to enter surface water
  • Manure applied to land subject to annual overflow from adjacent waters shall be incorporated within 48 hours
  • The Agency also highly recommends that the following practices be observed while the spreading ban is lifted:
  • Avoid spreading manure during or just before rain events. Remember that manure cannot be spread in such a way as to run off the intended site during application.
  • Where appropriate, incorporate manure as quickly as possible.
  • Avoid spreading manure on fields that are subject to annual overflow from adjacent surface waters. Manure spread on annual crop land that is subject to annual overflow from adjacent surface waters shall be incorporated within 48 hours.
  • Consider using split manure applications and reduced manure application rates.
  • Do not apply to land that is still snow-covered or frozen.

 

Frost Seeding: A Cheap Alternative to Improve Pasture and Hayland

Posted: March 7th, 2012 by outcropn

Looking for ways to increase forage quality and yield? Frost seeding is a good way to establish desirable species into an undisturbed sod at a low cost per acre. Read Dr. Darby’s article for specific information and to learn the key to increase the success of frost seeding establishment.

Key Crop Insurance Dates Just In for 2012

Posted: January 13th, 2012 by outcropn

Pam Smith, UVM Extension’s Crop Insurance Coordinator, just distributed the 2012 Key Crop Insurance Dates. The first deadline is 1/31 for AGR and AGR-Lite policies; sign up deadline for corn, soybeans, spring wheat, barley, and spring forage seedings is 3/15.

Organic Farming Symposium

Posted: December 19th, 2011 by outcropn

NOFA-NY’s ORGANIC RESEARCH SYMPOSIUM

SARATOGA SPRINGS HILTON

January 19th-20th, 2012 (preceding NOFA-NY’s Winter Conference)
NOFA-NY’s inaugural Organic Farming Symposium will take place on January 19th and 20th, 2012 at the Saratoga Springs Hilton. Join organic farmers from across the Northeast to hear from over 50 researchers–academics at some of this country’s most respected institutions, on-farm researchers, and PhD students–who will present their latest organic agricultural research projects. Engage in in-depth discussions with researchers and practitioners exploring the latest techniques for a successful organic farm. Share your own experiments and best practices with researchers and farmers.

Topics will cover organic fruit, vegetables, grains, soil, weed and pest management systems, ruminants and non-ruminants, and economics. Formats include one-on-one discussions with posters, panel sessions, and roundtables.

The goal of this Organic Research Symposium–NOFA-NY’s first ever–is to get farmers and researchers to meet, learn from one another, and collaborate moving forward.
Register here or call Katie (Registration Coordinator) at (585) 271-1979 ext. 512! Attend both the Symposium and the Winter Conference and receive an additional discount.

http://www.nofany.org/symposium

Sign up now for January 2012 Manure Applicator Training

Posted: December 19th, 2011 by outcropn

UVM Extension is offering a two-part course for anyone who applies manure to understand the rules and regulations with a goal of protecting the environment and conserving nutrients. The course will be offered from 10 am to 3 pm on both January 10 and 17 at the American Legion in St. Albans. There is no fee for farm owners, custom operators, or farm employees to attend; all others including farm service providers pay $60. For more information, see the program brochure.

Managing Flood Damaged Crops and Forage from Tropical Storm Irene

Posted: September 19th, 2011 by outcropn

Tropical storm Irene has caused some of the most massive flood damage to crops in over fifty years. Many crop fields were completely destroyed, while others were left with varying degrees of damage. Before making any decisions about your fields, you should document and report any crop damage to your local U.S. Department of Agriculture Farm Service Agency (USDA FSA) office, your crop insurance agent and the Vermont Agency of Agriculture, Food and Markets. You are strongly encouraged to take ‘time-dated’ photos of any damage. Such information may be critical in federal emergency determinations and your eligibility for these programs.
Click on the link below for the best management guidelines for harvesting, storing, and feeding flooded field and forage crops including corn, hay crops and pasture.

Managing Flood Damaged Crops and Forage from Tropical Storm Irene (pdf)

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