Lebanon Crop Management Video

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28 February 2011

soybean yield following corn

SOybeans planted after two continuous years of corn will yield about 6% higher yield than soybeans and corn in rotation. Iowa data suggests. What about Pa?

How Does Soybean Yield Fare Following Corn
By Mahdi Al-Kaisi, Department of Agronomy

Crop rotation and tillage systems can influence yield of both corn and soybean. It has been well documented that corn yield is variable due to crop rotation and different tillage systems; yields are usually lower in continuous corn compared to corn following soybean. Also, corn yield of continuous corn or corn following soybean is often lower with no-till system compared to conventional tillage, especially in poorly-drained and cold soils.

On the other hand, soybean yields under different tillage systems are similar at a given location, although differences in yield between soil types still exist. Nine years of results from long-term tillage and crop rotations studies in Iowa showed that regardless of tillage system or crop rotation, soybean yields are not affected by tillage system. This is encouraging news for producers who are reluctant to switch to no-tillage soybean after corn due to concerns of poor crop performance. With current increases in diesel fuel prices, some growers could save costs by minimizing tillage passes before planting soybeans.

The studies just mentioned were established in 2002 on seven research farms in Iowa with three crop rotations of corn-soybean (C-S), corn-corn-soybean (C-C-S), and continuous corn (C-C) as main treatments over five tillage systems, including: no-till, strip-tillage, chisel plow, deep rip, and moldboard plow. The experiment was replicated with a completely randomized experimental design. One of the objectives of these studies is to determine the interaction of tillage systems and crop rotations effect on corn and soybean production at different locations.

Soybean yield following one year corn or two years corn in the rotation shows different yield responses. Soybean yield in C-C-S rotations was on average 5 to 6 percent greater than soybean after one year corn (C-S) across all tillage systems and across the state (Table 1). However, the differences were variable among years and locations in various parts of the state. These differences reflect the effect of site specific conditions and management. But the trend shows an advantage in soybean yield following two consecutive years of corn over one year of corn in the rotation.

Potential causes for better performance of soybean after two years of corn may be due to reduced risk of some soybean diseases because of a break in disease cycle that may be associated with the corn-soybean rotation as documented in some research. Our results confirm other research findings here in Iowa that soybean yield after two years of corn have a slight advantage over soybean yield following one year corn. Economic return, input cost and other management considerations must all be taken into account before deciding to change crop rotations.







Mahdi Al-Kaisi is an associate professor in agronomy with research and extension responsibilities in soil management and environmental soil science. He can be reached at malkaisi@iastate.edu or (515) 294-8304.



soybean yield following corn

Using 10lbs per CEC point, Does it make sense?

Fact or Fiction: Ammonia Application Should Not Exceed 10 lb N per Unit Soil CEC
by John Sawyer, Department of Agronomy

There are two aspects to this supposed rule of thumb. One, what is the maximum rate of anhydrous ammonia that a soil can “hold” at application? Two, should this be used as a N rate recommendation?

Just what is soil CEC?
CEC is the abbreviation for cation exchange capacity. Cations are positively charged ions, examples being K+, Ca++, Mg++, NH4+. Since the soil has a net negative charge, cations are attracted to the negatively charged soil sites (called exchange sites) by electrostatic attraction (like a magnet). The CEC is determined by clay and organic matter – the source of negative charges in soil. CEC is an important soil property related to supply of certain plant essential nutrients, those taken up in a cation form (like K+, Ca++, Mg++, NH4+), and liming soils for pH correction. CEC is reported in a unit of charge equivalent; for routine soil test reports as meq/100 g soil (meq is the abbreviation for milliequivalent, a charge equivalent concentration rather than weight basis). The CEC for low organic matter, low clay content, and coarse textured sandy soils will be less than 5 meq/100 g, while high organic matter, high clay content, and fine textured soils will greater than 20 meq/100 g.

What happens when ammonia is injected into soil?
Anhydrous ammonia (NH3) reacts rapidly with soil water (immediately since ammonia is highly soluble in water), ammonium (NH4+) is formed, and can be held on the soil CEC. Remember that the word “anhydrous” is important, that is, there is no water in a tank of anhydrous ammonia. Therefore, when injected into the soil an initial reaction will be ammonia dissolution in water. This is why ammonia injury to skin can be severe, the reaction with water in cells, and why having plenty of clean water immediately available in case of an accident is vital to help limit injury.

NH3 + H2O = NH4+ + OH–

This reaction with water (consumes H+ ions) results in an initial alkaline pH in the ammonia retention zone (pH can temporarily rise above 9 at the point of highest concentration). It is free ammonia and not ammonium that moves and can be lost from soil if it reaches the surface. As pH increases above 7.3, the equilibrium between ammonium and ammonia results in increased free ammonia (the fraction as ammonia would be much less than 1% at pH below 7, 1% at pH 7.3, 10% at pH 8.3, and 50% at pH 9.3). The pH in the retention zone will remain high until nitrification results in a lowering of pH (produces H+ ions).



When anhydrous ammonia is injected into soil, several physical and chemical reactions take place: dissolution in water, reaction with soil organic matter and clay, and attraction of the resulting ammonium ions with the cation exchange complex. These reactions all tend to limit the movement and potential loss of ammonia. The ammonia retention zone has the highest concentration of ammonium near the point of injection (depending on rate, it can be greater than 2,000 ppm N), with a tapering of the concentration toward the outer edges. The greatest ammonium concentration is within the first inch or two of the injection point, and with many soils the overall retention zone is less than approximately four inches in radius (six inches in sandy soils). The size of this zone, and shape, vary greatly depending upon the rate of application and knife spacing, soil texture, and soil conditions at injection (moisture status and soil structure).

Ammonia moves farther at injection in coarse-textured soils and soils low in moisture. Also, if the injection knife causes sidewall smearing, then ammonia may preferentially move back up the knife slot. A similar movement occurs if the soil breaks into clods at application and there are large air voids left in the soil. Both of these conditions can result in greater ammonia concentration toward the soil surface, and greater potential losses at or after application (the same if the injection point is near the soil surface).

Bottom line, when ammonia is injected into soil, the initial reaction at the point of release is violent. The ammonia reacts and binds with soil constituents such as organic matter and clays. It dissolves in water to form NH4+. These reactions help retain ammonia at the injection point, not simply soil CEC. Using an acre furrow slice of soil (6 2/3 inch depth), the meq per lb applied N, as NH4+ equivalent, is only 0.0035. With the high affinity for water, soil moisture is important for limiting the movement of ammonia, but does not ultimately determine retention in soil. After conversion to ammonium, which is a positively charged ion, it is held on the soil exchange complex and does not move with water. Only after conversion to nitrate (NO3–), via the nitrification process, can it be lost from soil by leaching or denitrification.

Ammonia application rates
The rate of anhydrous ammonia that can be held in soil is not a direct relationship with CEC. Soil properties affect the size of the injection zone, but ultimately several other factors are more important, such as moisture content, depth of injection, and soil coverage, especially with dry soil or coarse textured soil. Wing sealers immediately above the outlet port on the knife can help close the knife track and reduce vertical movement of ammonia. Within agronomic rates of application, there is no real limit or maximum application rate (rates well above agronomic need can typically be injected). Anhydrous ammonia has been successfully injected into sandy soils at rates over 200 lb N/acre. In research conducted with alternate row injection (example 60 inch spacing in 30 inch row corn), more than 200 lb N/acre has been successfully applied – which is an equivalent of more than 400 lb N/acre per injection knife. It is injection depth and multiple soil conditions that determine potential volatile loss, not simply CEC.

Nitrogen rate determination
Across much of the Corn Belt the current approach to N rate recommendations for corn is the Maximum Return To N (MRTN). This approach uses yield response to N application from many response trials and economics (corn and N prices) to determine application rates. Information on the MRTN approach can be found in the Extension publication Regional Nitrogen Rate Guidelines for Corn and is used in the online Corn Nitrogen Rate Calculator.

Research has shown that soil properties such as clay and organic matter (components of CEC), or corn yield, are not directly related to economic optimal N rates. In fact, in many areas soils with low CEC and coarse texture (sandy) have higher N fertilization requirements that soils with higher CEC (for example, southern Illinois soils compared to central and northern Illinois; in Wisconsin, sands compared to medium and low yield potential fine textured soils). Therefore, if one simply used a “rule of thumb” such as 10 lb N per unit CEC (or some other multiplication factor) many fields would not be properly fertilized.




John Sawyer is professor with research and extension responsibilities in soil fertility and nutrient management.




anhydrousammoniarates

24 February 2011

LEBANON COUNTY FARMERS ARE SET FOR SPRING

150 Attend CMEG Crops and Soils Conference
By Sue Bowman

Good weather and the prospect of good information, good food and good camaraderie brought out 150 registrants to attend the CMEG Crops and Soils Conference at the Lebanon Valley Expo Center on February 23.  There was literally something for everyone at this event, which featured 29 workshop sessions on a wide range of topics, as well as 26 exhibitors from a variety of  agriculture-related businesses and government agencies.  There was also a forage contest along with awards and door prizes. And, of course, there was plenty of good food available, too, from morning fare of eggs served with an assortment of sausages to a hearty lunch of soup and sandwiches.

The conference kicked off with a general session where Dr. Paul Knight of Penn State's "Weather World" provided a video presentation on the Spring and Summer Forecast.  Two other general sessions later in the day focused on 2011 Tips for the Grain Market, presented by John Berry, an Agricultural Marketing Educator from Penn State Cooperative Extension, and a panel discussion on No-Till Drought Tips and Tactics moderated by Jim Hershey.

John Berry used a blend of professional know-how and humor as he pointed out the difficulty of projecting grain prices six months from now when meteorologists have difficulty accurately predicting weather a few days in advance.  Regarding their harvested grains, he told those assembled, "If it's in the bin, I hope you have it priced and, if not, what are you waiting for?"  He pointed out that cash prices tend to peak in May and June before waning as farmers try to empty bins to make way for the new harvest and buyers face the risks of next year's crop. Berry, who works out of the Lehigh County Extension office, stressed the important challenge of controlling fertilizer and seed costs.  He recommended "getting enough corn sold to cover your fertilizer bill and then worry about selling the rest of it later" as price trends continue to develop. 

Berry would like to see Lebanon County form a grain marketing group to meet monthly, as is done in surrounding areas.  Interested parties should contact Lebanon County Agronomist Del Voight at 717 821 0699_.  Berry emphasized that, "the market has no responsibility to give us a profit"; therefore, farmers have "got to be active with it."

Four experienced no-till farmers participated in the panel discussion about how to make no-till work during times of drought and other challenging conditions.  South Annville farmer Darren Grumbine told how he had previously shredded cornstalks until this year, when he allowed the corn stubble to remain.  He was pleased that it prevented loose organic matter from blowing around into piles and also helped keep snow in the fields better, which should help to recover nitrogen as well as preserve moisture.  Dave Wolfskill of Robesonia,Pa_ emphasized the importance of having a good spreader on the back of the combine because "residue is fertilizer."  He added that having residue managers on the corn planter will pay off with more even emergence due to reduced bouncing over residue clumps and manure that then leads to more uniform planting depth and germination.  Darryl Alger, also of South Annville Township, admitted that, although he's been no tilling for a long time, "I still have a lot more questions than answers."  The panel's general consensus is that what works well one year might not the next due to different variables related to everything from weather to crop rotation.  Panel members also noted that sometimes new techniques may appear to work but, if they don't result in a yield improvement, all you might have added is just another expense.  Thus, ongoing flexibility and evaluation is a must.  "You've gotta do what works for you," stated Grumbine.  "Watch what your crop's telling you," agreed panelist Dean James from_Danville, Pa_.

The panelists were split on the use of fungicides and herbicides, again depending on weather conditions and soil types.  As for when is the best time to start planting, the panel leaned toward as early in April as possible, though none put much stock in relying on a ground thermometer.  "If it's April, we like to go," said Grumbine, adding, "last year we were done by April 8."  Dave Wolfskill  pointed out that, "Nine out of ten years, my earliest corn is the best yielding."  He attributed this to getting as much growth and having the corn shaded over before heat stress sets in. Wolfskill mentioned that he wants his corn in full tassel by the Fourth of July or he knows he didn't plant it early enough.  Darryl Alger, who has successfully planted soy beans as early as March, said he doesn't go by the calendar; instead, when he sees a dandelion blooming it's time to plant.  He reasons that, the seed just sits there in the soil anyway if conditions are dry, which isn't much different than sitting in the bag of seed.    

One particularly popular session covered the upcoming reassessment of all real estate in Lebanon County.  Tim Bare of 21st Century Appraisals, Inc. spoke to a large group of interested farmers on the topic, "County Reassessment:  What It Means for your Farm".   Lebanon County will be undergoing its first reassessment since 1972, so Bare stressed that major changes in value have likely occurred during the intervening 40 years.  Bare noted that vacant land is the number one type of property to increase in value over time; however, he also reassured those in attendance that an upward movement in assessed value does not necessarily translate into higher taxes.  Since taxing bodies need to adjust their millage rates so that, overall, the reassessment is tax neutral, typically, one-third of properties will pay more taxes, one-third will pay less taxes and one-third will see their taxes remain virtually unchanged. 

Bare explained that every landowner in Lebanon County will receive their new assessed value by July 1, 2012 to allow time for review and possible appeals before the new tax structure goes into effect in 2013.  One bright spot for Lebanon County farmers is that the updated assessments will entitle them to participate in the State's Clean and Green tax reduction program for the first time.  Bare also encouraged farmers to apply for the possible property
tax relief already available through homestead and farmstead exclusions.

Other topics of the day ranged from herbicide and fungicide updates to the 2011 spring fertilizer outlook, as well as sessions on how to take advantage of the deregulation of electricity, farm diversity and various crop management updates.  Farmers went away from their day at the Crops and Soils Conference filled with new ideas and apparently eager for spring's arrival so they can put their newfound knowledge to good use.

21 February 2011

Wheat Stand Assessment

I recieved some calls from growers beginning to look at wheat stands.  Be sure to consider the uptake of N.  N Uptake Discussion in wheat with N Uptake Chart  For those that are getting 100 or more tillers already at this time perhaps holdiing off on N topdress is not a bad idea and time it to when hte wheat begins to take most of its N up at about GS4-5.  There was some producers talking about applying N at flag leaf and that is possible but by the time the N reacts and becomes available it might not be worth the application and also incurrs some damage from running through wheat at that time.
 Here is a link to a video that might assist in your processing stands for management.  Let me know what you are seeing as the season progresses.

Wheat Stand Assessment

11 February 2011

2011 Soybean Contest Brochure

Each year the Pa Soybean Board features a soybean contest. This year there are some major changes to attract more growers from different regions.  The benefit is tremendous when the group information is summarized and trends on management tactics are identified through the harvest report forms.  Here is the link to sign up for this event.

http://lebanon.extension.psu.edu/Agriculture/2011PaSoybeanYieldContest.pdf

Pesticide License Testing

Most folks have trouble understanding the licensing. I have developed a simple sheet with PDA that helps one understand what to go through to get a license.  We offer the test in numerous Extension Offices. I provide the Lebanon testing opportunities.  Here is the link. If you employ someone or if you are required to have a license to be employed  you will need to follow up and take the exam.

http://lebanon.extension.psu.edu/Agriculture/PestLicTestDates.pdf

2011 Grain Markets What to do and how to do it

Extension Specialist John Berry will talk grain markets, risk management through common sense marketing tactics that work.
Come hear his ideas and fiind out resources that can assist you in the process. Talk to other Farmers as to their plans for 2011 to make an extra .50 or a buck maybe 2 more per bushel you harvest.

http://lebanon.extension.psu.edu/Agriculture/CMEGCropsSoilsConfColor.pdf

What will the weather hold for 2011?

Dr. Paul Knight will podcast his predictions for the spring planting weather, summer slump and fall harvest. Hear what he has to say on the 23rd of Feb at the Lebanon Expo Center. Sign Up today.
http://lebanon.extension.psu.edu/Agriculture/CMEGCropsSoilsConfColor.pdf

Stalk Processing and Residue Management with the No Till Alliance and Farmer to Farmer Network

Jim Hershey and the No Till Alliance is heading to the Lebanon Crops and Soils Conference. Besides a hands on discussion of residue with a couple of stalk processing heads to look at the Alliance features Dave Wolfskill, Dean James, Darren Grumbine and Jim himself on a Farmer directed panel. What works the best? 

Come find out.  http://lebanon.extension.psu.edu/Agriculture/CMEGCropsSoilsConfColor.pdf
See a stalk processor in action--------

http://www.youtube.com/watch?v=XQUtKwYt8QI

2011 Silage and Forage Updates

With the high price of grain forage quality will once again be the key as well as storing that high quality forage. Paul Craig will detail key updates in Silage Forage management.  It is no wonder producers are coming to these sessions just a few ticks of quality can reduce purchased feed and protein supplements.

http://lebanon.extension.psu.edu/Agriculture/CMEGCropsSoilsConfColor.pdf

2011 Pests to contend with

Want to learn about what to expect on 2011? Then attend the CMEG Lebanon Crops Conference.  Dr. John Tooker will address key insect complexes for 2011 to include slugs, aphids and the stink bug.  Dr. Alyssa Collins will address the fungicide use in wheat. With $9.00/bu wheat it might be an important consideration.  Did I mention weeds.  John Bray will talk some new chemical combinations that may assist in preserving that yield. Sign up today at http://lebanon.extension.psu.edu/Agriculture/CMEGCropsSoilsConfColor.pdf

Electric Deregulation-Clean and Green - Land Reassessment 2011

We have a great slate to debate the pros and cons of many subjects specific to farms.  Dr. Dennis Buffington will debate the deregulation issues and offer simple common sense options to reduce farm inputs.  THe Conservations district will offer discussions on Clean and Green sign up benefits.  Tim Barr and Dan Seaman will address the reassessment and what it will mean to the Farmer.
CMEG-Lebanon Crops and Soils

Nutrient Management Credit Opportunity

Folks,
Dr Doug Beegle the foremost martial of the Nutrient Management and Soil Fertility circles will be presenting topics at the CMEG Lebanon Crops and Soils Conference that will attract Nutrient Management Credits. If you need some why not attend.  Aside from his fundings in injection of manure he will talk more about high yield farming with tissue testing.  Further Jeff Stine President of Sylvite will provide insight in the Fertilizer Futures for 2011.  Come join others in this effort.

CMEG Crops and Soils Conference - Lebanon

CCA Credit Opportunity

To the more than 130 CCA's here is a chance to gain more CCA credits for a nominal fee.
 1 NM-.5 SW-4 PM-3.5 CM Credits will be offered at the CMEG Lebanon Crops and Soils Conference.
Sign Up today!

CMEG Crops and Soils Conference

Pesticide Credits Offered

On Feb 23rd there will be a whole host of credits offered for private applicators.  A total of 5 credits will be offered to applicators in category and core material. A grower could gain 5 core or 5 category credits or do a mix.  The event is offered throught Penn State Extension Crop Management Group and offers numerous other important discussions. Topics will range from What is new in herbicide, the benefit of fungicides on wheat and key discussions on personal safety and this year how to check your poly tanks for safety.
For more information tap on this link and sign up today.
CMEG Crop and Soils Conference -- Lebanon

07 February 2011

Potassium Deficiency in Soybeans 2010

After a field diagnostic call from a grower. I decided to take pictures of the problem for diagnosis. You can see the field wide shot then as one walks the beans the tell tale K deficiency shows up with burn from the outside edge of the petiole. After collecting soil samples from the good and bad areas the resulting 45 ppm difference both low but at the 45 ppm level the deficiency was seen visibly. Finally after a 200lb/acre of muriate that afternoon the recovery of hte plants and quick turn around in the field.


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04 February 2011

Seed Corn Maggots Strike Again Spring 2010

Still not considering a seed treatment on soybeans. Here is a great example of what can happen to bare soybeans. This producer lost 60,000 soybeans and had to replant. Flies were all over the place in the field. We drilled another 80 ,000 beans into this field and they were treated and the producer was able to take off a nice yield at hte end of the year.
Take Home: Could have been avoided with a simple seed treatment.


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2010 Chemical Lessons

Here is a shot of a field of corn that had Basis applied pre the last nozzle did not cover the final row. Another great example of misapplication. There were surges in the field. Who knows whenever you get rain right after an application of residuals funky things can happen. The hybrid was also sensitive to ALS so between that and the rain immediately following application they came together in the cool weather that followed.



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Vertical Tillage Thoughts - Del Voight Senior Extension Agent- Penn State Extension

K State Video of theory behind Vertical Tillage
I liked this video from K state.  I took part in some demonstrations and have not had the time to get all the video compiled.  Here are some ideas and thoughts I have learned over the last few years.
Thoughts on Vertical Tillage. Needs more attention and research.
  1. It violates the definition of No till by the NRCS stating no full width tillage. Like it or not that is there stance.
  2. I have found it useful to warm soils where soybeans are to be planted in the spring. Research into this probably will find an early season growth differential.
  3. There are differences between manufacturers.  Some are fixed meaning they cannot be adjusted similar to the Great Plains Turbo Till and some can be made to perform as aggressive as the producer needs and can be viewed as a primary tillage tool in some circles.
  4. I would expect research to yield data to support quicker break down of residue due to mixing of the soil with the residue. I would expect little yield affect for corn and more perhaps for soybeans alfalfa, and wheat( even though I dislike growers planting wheat into corn for obvious reasons)
  5. Some growers in my area have retrofitted old discs with straight discs and made their own vertical tillage tool.
  6. Thinking about residue management, more work needs to be looked into using stalk processors on the head to allow for more uniform spread and breakdown over winter perhaps equallying the benefits of vertical tillage. I have seen planting issues with intact corn stalks pinning and pushing residue. I did not see this with a stalk processing head or flail chopped fodder.
  7. Leveling of the soil?  from what I have seen with a fixed type vertical tool there is little soil movement that would fill in holes or rills. Perhaps the more aggressive options could do that.
  8. On heavy soil where surface compaction is an issue research may prove this as a useful tool particularly where we do not "mind our manners" by getting on the soil when wet.
  9. Seeding cover crops post vertical tillage may prove beneficial for speed and seed to soil contact.  \
  10. SLUGS I did have a grower whom firmly believes his slug issue has been minimized by using vertical tillage spring and fall.  More work needs to capture that effect.
  11. How far away from a light disc is vertical tillage?
More work needs to be done in this area. Alot of growers have purchased these tools and like them that might be the true assessment.  I also  have growers that tried them and have opted not to purchase. Everyone has a different set of issues and they need to make the final notes.

Now is the time to get ready to overseed pastures. Del Voight – Senior Extension Educator – CMEG





The key to productive pasture is ensuring that all the effort in weed control and fertilizing is benefiting the grass that is established and will produce needed forage.  If a thin grass stand is in place or overgrazing killed some of it growers will need to replace those plants with new ones.  Now is the time to get the seed and be ready once the snow melts in February to over seed. Here are a couple of tips.
                                                               i.      Over seed with full rates of seed in February of each year until the pasture is completely covered by grass as a frost seed or in August before fall rains or even better a hurricane. 
1.       Grasses like Orchard grass 10 lbs, bluegrass 8 lbs, ryegrass 6 lbs and smooth brome grass 14 lbs will generally have  a @ 20% take if over seeded (so it may take 10 years of overseeding to completely fill in.  However, a drill and or a disc/culti-packer increases the “take” and a quicker stand will come in but it will take more management to do that.There are differences in how grass species respond to simple overseeding, Diploid(10-20lb/a) and Tetraploid Ryes are effective for over-seeding without using any other tools.  I have used these tools in my own pasture and they worked great. But they are short term grasses and will last about 2-3 years while the orchardgrass and other perennials are long lived.
2.       Clovers specifically improved ladino clovers respond about 70% to frost seeding and they will take hold with moderate seed to soil contact due to the size and density of the seeds. Do not over-seed into a Cimarron(or other long residual herbicides) treated area until after one year has elapsed.  Refer to the Agronomy guide for specifics. If you choose legumes you will limit your weed control options so be sure the weeds are completely under control before using legumes in the stand.
3.       One can over-seed with a walk behind spinner spreader, a drop spreader, a hand carried spinner or some even combine a fertilizer application and mix the seed in with the fertilizer. To do this one would need to rent a buggy and have a plant food (fertilizer) dealer mix it thoroughly. I also ran into a producer that mixes clover seed in with his cattle free choice mineral and when it is deposited in the manure the seed germinate.
                                                             ii.      Sources of seed, P.L Rohrers(James Patches, Umbergers K and K), Seedway(Umbergers, Kirby Agri, Grow Mark, F.S), Kings Agri Seeds (Abner Stoltsfus), American seeds (Charlie Bomgardener). Chemgro also has seed as well as others that I failed to include.


Growers will have to make their own decisions but nature provides this time of year to assist growers in thickening thin stands of grass.
http://lebanon.extension.psu.edu/Agriculture/FarmMgt/Horsepasturerecommendationsletterhead.doc