A UVM blog Out Croppings: Important crop news from the field!

Dr. Heather Darby, UVM Extension Agronomist

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Recent intense rainfall events have caused flooding, ponding, and soil saturation in many of our corn and hay fields. What are the prospects for these crops?

Corn Fields
Corn planted nearly two weeks ago around the state is just now beginning to emerge and doing so very erratically. The cause of the problems are multiple and include dense soil surface crusts restricting coleoptile emergence, seed rots, seedling blight, stress from saturated soils, and some insect damage. To determine seed health, dig up many seeds in the field and determine condition of the seed. A soft mushy seed is a sign of death. If the corn has started to germinate, check to see if the shoot is healthy and not easily detached. In addition, severe crusting has added to the problem. Corn emergence will be challenging when a dense surface crust sets. The resistance of a crust to corn penetration often results in corkscrewed corn elongation below the surface and eventual leafing out underground. Monitor fields and be prepared to use a rotary hoe (or some other implement) to break the crust and aid emergence. You can also take the planter back to the field and run them shallowly over the existing furrow to break the crust. Of course, the challenge with this strategy is to balance the benefit of breaking the crust while avoiding damage to the emerging seedlings. A side benefit to breaking this crust is improved aeration for the crop.

Flooded or ponded soil creates other risks for corn that has already emerged. Soil oxygen becomes depleted after about 48 hours of soil saturation. Without oxygen, corn cannot perform critical life functions (i.e. nutrient uptake, root growth inhibited). Since the growing point of corn at this stage is still below ground it is directly subject to the stress of oxygen depleted conditions. The likelihood of crop injury is less where the flooded and ponded conditions last less than 24 hours. To confirm plant survival, check the color of the growing point and look for new leaf growth 4 to 7 days (with 70 degree weather) after the water drains from the field. Healthy growing points will be firm and yellowish-white, not mushy and discolored.
Many growers are faced with the challenge of accurately assessing the extent and health of surviving stands in order to make a reasoned replant decision. The challenge lies in the fact that germination and emergence have been so very slow in response to the dramatic cooling down of soils that occurred with the arrival of the rains. Remember that slow germination and emergence by itself does not automatically translate to a failed stand. IF (note the emphasis on “if”) such delayed seedlings are otherwise healthy, they will likely develop into normal plants. The bottom line is that until emergence is complete, it is nearly impossible to accurately estimate effective plant populations across entire fields. With the current warming trend, growers should be in a better position by the end of this week to make these important stand assessments. Remember that only portions of the field may need to be replanted. Compare this population to the original target population. If you are in a situation where corn needs to be replanted remember to consider a shorter season hybrid.

Hay & Pasture Fields
Forage plants (other than perhaps wet site-tolerant reed canary grass) can survive for several weeks in saturated soils, but the lack of oxygen in the root zone will adversely affect their growth. These plants do not take up soil nutrients normally, an increasing part of the root system deteriorates, and legumes cease ‘fixing” nitrogen. They appear stunted and yellowish-green in color. If the soils drain quickly, plants begin to recover. Flooded forages contain fine silt, fungus spores, bacteria that are bad for you and your animal health. The forage that has been flooded with silt and debris can cause health problems, production problems, and/or reproduction problems in livestock. To be safe, avoid making silage out of it. However, if you do, keep it separate from the rest of your unflooded silage. It may spoil and it could contaminate adjacent silage. If you ensile these flooded crops, you may find that once the silo is opened, they spoil faster than other silage. Generally, you should avoid feeding this material if possible. However, if you haven’t already done it, try to get this standing material off the field as soon as possible to encourage regrowth. If hay fields were flooded remember to wear a dust mask when harvesting. Grazing animals can be exposed to clostridial organisms that can lead to some serious diseases. The safest approach would be to clip the contaminated pastures and then wait to graze the regrowth. But don’t graze it too closely – avoid letting your livestock get down into the old dead material. Watch your livestock closely. If any of you animals appear sick, call your vet immediately.

If you have any questions please contact Heather Darby @ 524-6501 or heather.darby[at]uvm.edu

Having had the wettest spring on record there are many fields that still remain unplanted. Many farmers are asking about alternative forage options to secure enough feed for the year. Although prime time to plant corn has passed there are still options available to secure high quality forage for the winter months. Read more to learn about options for late season forage production.

by Dr. Heather Darby UVM Extension Agronomist

Many farmers have reported alfalfa fields that have been slow to green-up this spring. Having had a harsh winter it is highly likely that some forage fields have suffered from winter injury.  This article will present some options for managing and enhancing winter injured alfalfa stands.



What causes winter injury? There are many factors that can contribute to winterkill such as deficient snow cover, variety, cutting management, fall soil moisture, stand age, low soil fertility, and low soil pH.  Alfalfa prepares itself for the winter months once temperatures drop below 40 degrees F.  During this time the plant prepares itself to tolerate freezing temperatures between 5 and 15 degrees F.  When temperatures drop below this threshold the water in the plant cells freeze and lead to further cell damage, dehydration and eventually can lead to plant death.  Winter injury can also be caused by ice sheeting that prevents air exchange to the alfalfa crowns.  One way to reduce damage from ice sheeting is the recommended practice of leaving 6 to 8 inches of stubble in the fall. This will also increase the chances “catching” snow, which acts as an insulator.

How to diagnose winter injury?  The most obvious sign of winter injury are stands that are slow to green up.  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.  The best way to diagnose damage is by examining the plant roots in a suspect field.  To do this walk diagonally across a field and at regular intervals, dig up a shovel full 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 wintered killed.  Try and inspect as many plants as possible to determine the percentage of your stand and/or areas of your field that are injured.

Options for fields moderately affected by winter injury

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

1. Allow alfalfa plants to mature longer 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 early flower for following harvests.
2. Increasing the cutting height may also help stands recover.  New shoots will be developing at the base of the injured plants and it is important to not remove these shoots as it will result in further detriment.
3. 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 predominantly grass stand, then you could manage it for grass.  This will work best if the grass species are predominated by tall growing species such as reed canarygrass, orchardgrass or timothy.  If the grass is less than 10 inches tall, it may still be economical to apply 50 pounds of N per acre to boost yield and protein.

If the alfalfa stand was only partially injured (25 to 50 %) interseeding with quick germinating forage with a no-till drill could provide additional production.  Species that could be considered for interseeding include orchardgrass (4-6 lbs/acre) perennial ryegrass (5-6 lbs/acre), or clover (4 lbs/acre).  Remember that alfalfa should not be reseeded back into the field unless the stand is only a year old.  Autotoxicity issues will keep the newly seeded alfalfa from growing. Perennial ryegrass should be considered a short term option since it does not overwinter well in our climate.

Options for fields severely affected by winter injury

If your stand was over 50 % killed, you may want to consider replanting. Depending on your needs, there are several forage choices.  A small grain/field pea mixture will be the best choice if the forage is needed in early/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 Vermont has reported dry matter yields between 2.5 and 3.0 t/acre.

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 out yield 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 and millets.  The sorghum-sudangrass hybrids and sudangrass should be seeded at 50 lb/acre, while forage millets are planted at 20 lb/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 we are experiencing average to cool temperatures.  Studies conducted at the University of Vermont have reported dry matter yields between 4 and 6 t/acre.

Each potential forage option listed above has advantages and disadvantages. How you decide to manage your winter injured fields will depend on the required forage yields and quality for your farm.

For more information on how to manage winter injured alfalfa fields please feel free to contact Dr. Heather Darby at 524-6501 or heather.darby[at]uvm.edu.

Excessive rainfall and flooding in Vermont during April could create locations where the prevented planting provisions of crop insurance policies may apply. Follow this link for a helpful fact sheet;Prevented Planting Insurance Provisions: Flood, which highlights the flood or excessive moisture prevented planting provisions for producers covered by crop insurance. Because conditions vary significantly between geo­graphic areas, loss determinations are based on each producer’s individual circumstances. It is very important to contact your crop insurance agent with any questions. It is necessary to report a prevented planting loss. Good record keeping and documentation is key to receiving prevented planting payments. Producers should work with their approved insurance provider to determine the documentation needed for their specific prevented planting claim. In addition, when filing acreage reports, reporting all acres of prevented planting is essential in order to receive full credit for the crop.

Tuesday, February 22, 2011
11:00am – 3:00pm
Fournier’s Farm Equipment
Rte 78 Swanton, VT

Download a copy of the brochure here.

– Learn how to convert a conventional planter to no-till and reduced tillage.
– Renowned expert Joel Myers, long-time no-till farmer from Pennsylvania will be there to offer advice and help explain the tools of the trade.
– Hear from farmers from our area who have had successful experiences with cover crops and reduced tillage cropping systems.
– Attendees will be eligilible for cost-share to convert their own planters.
Cost: $10, includes hearty lunch. To register, please call the UVM Extension office in St. Albans by February 16, 2011 at 802-524-6501. For more information please contact Heather Darby 802-524-6501 or , email
Directions:
Take I 89 North to exit 21 for VT-78 toward US-7 Swanton. Turn Left at VT-78 W/1st Street. Turn Right at Grand Ave. Turn left at Merchants row. Turn right at VT-78W/N River St. Fournier’s Farm Equipment is on the left.

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Workshop sponsored by:
Lake Champlain Basin Program
Northeast Sustainable Agriculture Research and Education
NRCS Conservation Innovation Grants
University of Vermont Extension

Sediment Abatement Project for Rock River and St.Albans Bay

Friday, January 28th
Swanton House of Pizza meeting room – Rt.78 downtown Swanton Village
10:30 am to 1 pm

Agenda

Slideshow and discussion of fall cover cropping activities
–    Impact of seeding date on cover crop establishment in 2010
–    Spring termination of cover crop strategies – roller/crimper, spray, tillage
–    Review of most cost-effective strategies for local soil types and conditions
–    Short-season corn varieties
–    Observations of reduced tillage plantings
–    Addressing compaction through subsoiling or tillage radishes

Presenters include:
–    Heather Darby, Ph.D., University of Vermont Extension
–    Brian Jerose, WASTE NOT Resource Solutions

Noon – Lunch Provided – Farmer Peer Discussion

Planning for Spring 2011
–    Interest in strip-till, zone-till, no-till and subsoil implements
–    Opportunities for critical area seeding, manure injection/incorporation
–    Conservation tillage trials with UVM Extension
–    Other sediment abatement practices of interest – grassed waterways

Publications available free to farmer participants: Managing Cover Crops Profitably, Steel in the Field, Building Soils for Better Crops and other handouts

Support for this workshop provided by: Friends of Northern Lake Champlain (FNLC) via a Vermont Dept. of Environmental Conservation Grant for Sediment Abatement in the Rock River and St.Albans Bay watersheds, UVM Extension and the Franklin-Grand Isle Counties Farmers Watershed Alliance (FWA).
For more information and to RSVP for lunch please contact:
Brian Jerose, WASTE NOT Resource Solutions
(802) 933-8336 or email

Organic dairy producers will learn about animal nutrition, herd health considerations, the latest agronomic research, and more at a day-long workshop on Jan. 13.

The Vermont Organic Dairy Producer Workshop will be held at the Red Schoolhouse on the Vermont Technical College (VTC) campus in Randolph Center from 10 a.m. to 4 p.m. Registration is due by Jan. 7. The fee is $20 per person and covers lunch and materials. To register, send a check, made payable to University of Vermont Extension, to Organic Dairy Workshop, UVM Extension, 278 S. Main St., Ste. 2, St. Albans, VT 05478. If you require accommodations to participate in this program, please call 524-6501 or (800) 639-2130 by Jan. 7. For more information, please see the workshop brochure at http://bit.ly/gRzPWR.

The workshop will start with a presentation by Dr. Heather Darby, UVM Extension field crops and nutrient management specialist, who will describe results of the latest research conducted by her team, including organic forage studies, grains trials, and other projects. Dr. Kathy Soder, an animal scientist with the U.S. Department of Agriculture’s (USDA) Agricultural Research Service Pasture Systems and Watershed Management Research Unit in Pennsylvania, will discuss developing low and no grain feed strategies that complement high quality homegrown forage production. She also will describe the effect of plant species diversity on intake, productivity, and grazing behavior.

A panel of veterinarians–Drs. William Barry of Brookfield, VTC’s Chris Dutton, and Hubert Karreman of Penn Dutch Cow Care, Lancaster, Pa.–will address herd health questions posed by participants. In addition, the workshop will include a live broadcast by Dr. Charles Benbrook on the Shades of Green Calculator, a tool that helps estimate environmental, animal health, production, and economic impacts of different dairy management practices. He also will highlight findings of a recent study of farms that have used the calculator. Benbrook, chief scientist with The Organic Center, a national organization providing scientific studies on organic farming, is currently an adjunct professor at Washington State University.

The workshop is sponsored by UVM Extension; the Northeast Organic Farming Association of Vermont; Organic Valley, a Wisconsin-based organic farm cooperative; the USDA Risk Management Agency; Northeast Sustainable Agriculture Research and Education; and eOrganic, a web-based organic agriculture resource.

Hi Folks,

I sent out an email alerting readers to scholarships available for Gorst Valley Hops’s Hops 101 and 201 in Cooperstown, NY last week, only to be contacted by numerous people saying that they hadn’t received the email.  I’m not sure what happened in the ether of cyberspace, but allow me to reiterate here:  There are scholarships available for the workshop, please contact me if you are interested.  Also, if you do not receive the occasional email from me concerning UVM Extension’s latest work with hops, and would like to be included on that list, shoot me an email, and I’ll add you.  No spam, I promise.

Hope to see you there,

Rosalie

Dr. Heather Darby, Agronomic Specialist, UVM Extension

Once again, I have seen increased Northern Corn Leaf Blight (NLB) pressure in our area.  I have seen severe damage in the river valleys where dense fog and heavy dews are common.  Northern leaf blight is a fungal disease found in humid climates wherever corn is grown. The disease thrives when relatively cool summer temperatures coincide with high humidity and available moisture.  The number of NLB outbreaks has increased considerably over the past 5 years.  Corn silage yield and quality losses from this disease can be significant.  Therefore it is important for us to gain a better understanding of the disease cycle, symptoms, and management practices that can be employed to reduce the impact of NLB on the corn crop.

Disease Cycle

Northern corn leaf blight is caused by the fungus Exserohilum turcicu.  It overwinters as mycelia and conidia in diseased corn stalks (Figure 1).  In the spring and early summer, spores are produced on this crop residue when environmental conditions are favorable. Primary infections occur when spores are spread by rain splash and air currents to the leaves of new crop plants.  Infection will occur if free water is present on the leaf surface for 6 to 18 hours and temperatures are 65 to 80F.
Secondary infections occur readily from plant to plant, and even from field to field.  Infections generally begin on lower leaves first and then progress up the plant. Heavy dews, frequent light showers, high humidity, and moderate temperatures favor the spread of the disease.

Disease Symptoms

Within 2 weeks of infection grey elliptical lesions begin to develop on the leaves.  Over time the cigar shaped lesions become tan as they enlarge (Figure 2).  Under moist conditions, the lesions produce dark gray spores on the lower leaf surface. As many lesions enlarge and coalesce, entire leaves or leaf areas may be covered.
It is obvious that the more leaf area that becomes damaged from this disease the more yield and quality losses that maybe incurred. Generally, the damage on the plants is seen after silking, however, there have been earlier infections reported in the moist valley regions.

Disease Management

One of the most effective means of managing NLB is selecting resistant corn hybrids (Figure 3).  Since we have not recognized this disease as a major threat focus on resistant hybrid selection has not been a priority. Hybrids with above average resistance to NLB should be planted.  Work with your corn seed representative to select hybrids that meet these criteria.
Since corn residues harbor the disease, all fields that are grown for grain may be at the greatest risk for disease infection.  In areas where NLB problems have occurred in recent years, reducing any previous corn residue is important to minimize disease inoculum and its effects. Corn residue can be reduced through several practices including crop rotation and moldboard plowing.  Remember that this disease has been seen primarily in continuous corn silage fields in Vermont.  Therefore, any amount of residue will increase the risk of this disease.
Although there are fungicides available to protect the corn from this disease they are generally not considered cost effective in corn silage systems. If you suspect that your corn has Northern Corn Leaf Blight please report the incidence to UVM Extension Agronomists Heather Darby.  For more information please contact Heather Darby at (802) 524-6501 or email.

University of Vermont Northwest Crops and Soils Team’s Grain Quality Laboratory is up and running!  The team headed up by Heather Darby, received funding through the Castanea Foundation located in Montpelier, Vermont and generous private donations to purchase a sophisticated machine to test the Falling Number of wheat, an internationally standardized method for sprout damage detection.  The Falling Number System measures the alpha-amylase enzyme activity in grains and flour to detect sprout damage, optimize flour enzyme activity and guarantee soundness of traded grain. Alpha-amylase activity is crucial for final product quality of bread, pasta, noodles and malt.

The lab is also equipped with near-infrared technology for protein analysis and employs a method to test for deoxynivalenol (DON) also known as vomitoxin.  Occurrences of this vomitoxin in wheat at or above 1 ppm are considered unsafe for human consumption by the FDA.  Contamination of wheat with DON is directly related to the incidence of Fusarium head blight and strongly associated with relative moisture and timing of rainfall at flowering.

Our lab is currently accepting samples and will continue to do so until December 1, 2010.  Click here to download a Cereal Grain Test Submission Form.  In order to get results that accurately reflect your product, be sure to employ good sampling techniques.  Remember the results are only as good as the sample submitted! For more information on testing the quality of your grains, contact UVM Extension’s Crops and Soils Team.