Field Crop News

Website Address: http://fcn.agronomy.psu.edu/

July 29, 2008 Vol. 08:21

IN THIS ISSUE:

Weather Outlook
Tasks at Hand
Summer Establishment of Forage Crops
Summer Seeded Oats
Soybean Aphids and PIPE Systems
Blue Mold Present in Tobacco Fields
No Till Corn Turning Green
Get Ready for Corn Silage Harvest
Cover Crops after Small Grain and Corn Silage Harvest
Invasive Earthworms
Crop Report from Northern PA
Upcoming Events

Weather Outlook — Paul Knight, Pennsylvania State Climatologist

The heavy rains of last week brought as much as 4 to 5 inches of rain to sections of Pike and Montgomery counties with much of the eastern quarter of the state receiving between 2 and 4 inches ending a prolonged dry spell. The seasonably warm and dry weather of earlier this week will give way to a brief spell of sultry conditions on Wednesday and part of Thursday. Scattered thunderstorms late Wednesday and Thursday will mark the transition to a warm, drier air mass. A steady warming trend will commence during the weekend and reach its pinnacle about this time next week with several record maxima likely. A 3 to as much as a 5 day heat wave is expected starting either Saturday or Sunday and diminishing on Wednesday or Thursday of next week. Readings will reach 100F or a bit higher in sections of southeast and south—central Pennsylvania. Much of the time, it will be sunny with an active breeze each afternoon. Expect significant drying and only widely separated thunderstorms between 2 and 9pm each day. A push of less humid, but still warm air will arrive later next week, but there are signs that the heat may return during the second week of August. The tropical Atlantic should stay quiet until mid—month.

Check out the predicted Growing Degree Days (base 55) for Pennsylvania for the next two weeks.

Tasks at Hand — Mena Hautau

Is It Time to Seed Alfalfa?
A growing “clue” to watch in your area of the state is day and night time temperatures for summer seedings of forage crops. Daytime temperatures may still be quite warm, but when night time temperatures begin to cool to less than 70 degrees consistently, it is time to start thinking of planting cool season crops. You can check weather stations around the state for high, low and average temperatures.

Some parts of the state are very dry, while others have adequate soil moisture. In areas of good soil moisture in the surface and subsurface, growers should think about getting started with new seedings of alfalfa and other small seeded forages.

Soil Sampling
Take a soil test, check your soil pH and make sure it is at least 6.5 to 7.0. Check that your soil test levels for nutrients are optimum. Line up your seed and appropriate equipment. For information on yield data, check the 2007 Forage Reports.

Drill Calibration
Conduct a test run with your drill or planter to check seeding depth, especially if doing no-till. Alfalfa seeds should not be planted deeper than .25 inches. Having good soil to seed contact is especially critical. As the small seeds germinate, they produce tiny roots. Soil contact is the medium for survival. Be sure to consider soil moisture levels at planting time.

Planting on time ensures that the crop has time to establish itself, store needed food reserves and hardens off before winter. Next spring, your alfalfa will be off to a roaring start when it breaks dormancy, ensuring its competiveness against annual weeds.

Summer Establishment of Forage Crops — Paul H. Craig

Typically forage producers refer to the two establishment periods for forage crops as spring and fall. Actually the second period is mid to late summer and not fall. Many forage growers actually prefer late summer seedings primarily due to reduced insect and weed pressures. Usually summer seedings of forages are in small grain stubble fields or in fields where a spring establishment has failed.

Most alfalfa growers are aware of the allelopathic effect of old alfalfa stands on a new seeding. Research has found that old alfalfa crowns and roots exude a toxin that inhibits the germination and development of new seedings. This is one reason why alfalfa producers rotate their stands for at least one growing season prior to a new seeding. Another reason for rotating is the buildup of alfalfa diseases in an older stand and the opportunity to utilize the nitrogen produced by the alfalfa crop by a succeeding corn crop in a rotation. However, the short interval from spring to mid-summer and the fact that the stand is considered a failure allows for a summer seeding to remedy a failed stand.

There are a few risks associated with summer seedings. The primary concern is moisture stress during germination and seedling development. Avoid seeding when soil moisture levels are low in the upper 3 to 6 inches. Watch short term weather forecasts and be prepared. No till establishment will minimize soil moisture losses.

Post establishment weed control challenges will need to be monitored. Summer annual weeds will not become well established. However, winter annual weeds including chickweed or purple deadnettle and many others, will germinate in September and October and can present significant problems if not controlled. In small grain stubble fields volunteer small grains can present another weed control issue. There are many options for weed control available. Treat this year, when weeds are small. Controls next spring will be less affective.

Early to mid-August is the preferred time to sow alfalfa in south-central PA to ensure optimum establishment and production next spring. However later seedings do occur with some stands sown as late as mid September. Work at Penn State by Dr. Marvin Hall, forage specialist has taken a look at optimum summer seeding dates.

Dr. Hall’s work has shown that delays in forage seeding results in a reduction in plant height in late November, a reduction is the amount of the field that is occupied by the alfalfa (plant vigor) and a lower DM yield the next growing season for delays after August 1 in central PA. He concluded that delaying planting by 2 weeks after August 1 can result in a loss in production the following year by approximately 0.5 ton/acre. By delaying 4 weeks (late August) to plant alfalfa the yield reduction was 1 ton/acre the following production year.

Dr. Hall also compared summer planting dates for three grass species, Orchardgrass, Ryegrass and Reed Canarygrass. His results with grasses indicate that late August seedings are preferred for orchardgrass and ryegrasses; however, Reed Canarygrass yields were higher with the earliest seeding dates and planting canarygrass after September 5 resulted in poor plant vigor and lower DM yields the following spring.

Do not harvest late summer seedings this fall. By not harvesting root reserves will be maximized this fall resulting in improved winter survival and rapid plant development next spring. Next spring; manage the stand as you would your other established stands.

In summary, planting forage crops during August is preferred across southern PA but these crops can survive through the winter if planted a few weeks after this period. However, delaying planting will result in a reduction in plant vigor and lower yields as a result of this delay in establishment. Planting after late September can result in severely weakened stands next spring.

Summer Seeded Oats — Paul H. Craig

One forage alternative many dairy farmers are incorporating into their agronomic practice is the use of summer seedings of oats for fall harvest. In recent drought years many dairymen have sown oats into barley and wheat stubble. Other livestock producers have no tilled oats into old hay fields or pastures for emergency forage production. Some dairy nutritionists consider small grain fiber as a good complement to highly digestible corn silage in many dairy rations.

Spring oats can be planted any time during the summer if soil moisture is sufficient for germination and development. Target dates for seeding should be prior to mid-August in most parts of the state. Many growers will use bin-run feed oats after they complete a germination check to test for seed viability. The forage seed industry has evaluated and promotes the use of specific forage oat varieties. Seeding rate is 2.5 to 3 bushels/acre.

Soil fertility is critical for optimum forage production. Applying 60 pounds of nitrogen is recommended. Many dairy and livestock producers will apply pit manures to fields prior to planting. To minimize the loss of existing soil moisture levels no till is preferred over conventional tillage. A burn down herbicide to control emerged annual grasses and broadleaves is needed in no till seedings. Staggered plantings will spread out harvest and reduce the risk of unfavorable growing and harvest weather.

Oats need about 90 days to reach harvest and yields can approach 2.5 to 3 tons of dry matter per acre. Harvest is targeted for the early heading stage of the crop. At this stage fiber levels will be in the target range. Delaying harvest results in high lignin levels and harvest at the boot stage can be too digestible. Know what your forage needs are for your feeding program by talking to your herd nutritionist and harvest accordingly.

Hay making of oats will be out of the question; however, silage harvest, baleage or grazing can be used. When harvesting for silage include silage inoculants developed for cereal crop silages. Shorter days and colder nights will significantly reduce natural populations of bacteria on the crop.

Oatlage will require some field wilting. Moisture levels between 60 – 65% are best for ensiling small grain silage. Small grain silage below 60% moisture is difficult to pack and excessive heating and nutrient loss may occur. In addition, making sure that the theoretical length of cut is less than 3/8 inch is important with small grains because as the crop matures stems become more hollow and harder to pack. Minimizing the length of the chopped material will help reduce silage heating in more mature stands.

Soybean Aphids and PIPE Systems — John Tooker, PSU Entomology Specialist

This is typically the time of year when we can expect soybean aphid populations to start to increase and become apparent. This year, however, aphid populations in Pennsylvania appear to be developing more slowly than usual. About this same time in 2004, the economic threshold of 250 aphids per plant was surpassed in research plots at Penn State’s Research Farm at Rock Springs, PA.

A recently developed website pest prediction tool called PA PIPE has been introduced. PA PIPE indicates that the earliest soybean aphid populations should be well along in their development by now, particularly in southeastern PA. Nevertheless, we have not heard of any substantial populations of soybean aphids in PA so far and this is a trend reflected on a national scale also.

The PA PIPE system (http://pa-pipe.zedxinc.com/cgi-bin/index.cgi), is a predictive modeling Web site developed by Dennis Calvin and supported by Penn State’s College of Agricultural Science. Penn State is participating in a national effort to track soybean aphid populations and the spread of soybean rust. This system is freely available online; http://sba.ipmpipe.org/cgi-bin/sbr/public.cgi and includes data and commentary on soybean aphid activity across the US.

PIPE will be a valuable crop pest information system because it will allow agronomists, pathologists and entomologists to track pests annually over the entire country. When combined with weather data, this database should allow researchers to predict when and where aphids (and soybean rust) are likely to cause problems. A team at Penn State is sampling five sentinel plots weekly across the state. To date only one plot has shown any aphids. States to our west, including Ohio, Kentucky, Indiana, and Illinois, are also reporting low numbers of aphids, which is good for Pennsylvania because any storms moving eastward from the Midwest will not be able to pick up too many aphids in those states and blow them into PA.

Despite the low numbers of aphids at present, growers would be wise to scout their fields regularly in the coming weeks. Soybean aphids develop clonally without going through an egg stage. In fact, young aphids can already be ‘pregnant’ when they are born, so populations can increase exponentially in warm weather typical of late July and August.

Blue Mold Present in Tobacco Fields in PA — Jeff Graybill

Fields displaying blue mold infections began showing up in Lancaster and Chester counties about July 1^st of this year. It is critical for tobacco growers to scout for the presence of this disease and take appropriate action. Several products are available to choose from including Acrobat, Manzate, Dithane and Actiguard. Be sure to check the label and the recommendations of your tobacco buyer when applying these products. Also, it is important to keep in mind that all of these products work best as a preventative and protectant; therefore, for best results they should be applied before the disease is found in your fields.

Blue Mold will not survive the winters in Pennsylvania, therefore viable spores must blow in on summer storms from the south or be carried north on contaminated plants or equipment. The disease is also favored by cool and wet conditions. Thus it is difficult to predict when the disease will surface and how severe infestations will be from year to year. Lancaster Leaf Tobacco Co. has a blue mold hotline which growers can contact to see if the disease is present and whether they should initiate spraying. The hotline number is: 717-239-4414.

A photo of what severe blue mold symptoms can look like appears above. They generally start as spots the size of a quarter on the lower leaves. The underside of the spot will sporulate showing a fuzzy bluish color. Once tobacco is topped its susceptibility to this disease greatly decreases and fungicide applications can generally be stopped.

No Till Corn Turning Green — Sjoerd Duiker, Soil Management Specialist

In a previous issue of the Field Crop News we commented on the difference in greenness of corn in tilled soil compared with that in no-till soil. In one of our trials where we compare no-till with chisel/disk corn we also observed some of that earlier in the season. In fact, we measured a much higher nitrate concentration in the tilled soil with the PSNT test. Inspecting these fields last week I noticed that the corn in the no-till fields has now become as green as that in the tilled fields, and looking as tall. It seems the decomposition of organic matter in no-till soil is kicking in, releasing nitrogen when the crop needs it, whereas in our tilled soils that release will now dramatically slow down. I encourage you to observe your no-till crops now and compare them with the tilled crops.

Get Ready for Corn Silage Harvest — Paul H. Craig

All indicators are that if the present weather trends continue, many of the earliest plantings of corn will be ready for chopping by late August. Estimates place corn silage harvest approximately 40 to 45 days after tasseling depending on many environmental factors. Now is the time to get organized to take advantage of this potential crop.

First, make sure all harvesting equipment and storage facilities are ready to go. Clean out all old silage before adding this year’s crop. Check all surfaces for cracks or holes. Check surface water drains to make sure they are opened to allow effluent to move away from silage. On upright silos check door seals, ladders and safety cages. Lubricate and adjust unloaders and make certain support cables are strong. Engineers note that any silo, older than 10 years, should be checked for structural integrity. A quick inspection may save lives and thousands of dollars in lost feed and damaged property.

Harvesting equipment should also be serviced at this time. The last thing a silage producer wants is a delay in harvest due to equipment failure. Check filters, hoses, fittings, belts, chains, bushings, sprockets and order replacement or spare parts. Sharpen knives and cutter bars and check the accuracy of cutter head adjustments and processors.

If you are filling a bunk or making a pile make sure you have access to sufficient packing equipment, plastic for covering and labor to complete this task. Consider inoculants. Research proven inoculants can help to speed up fermentation or alter fermentation to minimize spoilage at feedout. Visit with your feed dealer to determine which might be best.

Cover crops after small grain harvest and early corn silage harvest — Sjoerd Duiker, Soil Management Specialist

The time is here to start acting on cover crops after small grain and corn silage harvest. Our research has shown the importance of timely establishment of legumes to obtain a substantial nitrogen fertilizer value next year. The legumes that came out as most promising for fallestablishment were crimson clover and hairy vetch. Now would be the time to establish these cover crops in the northern regions of Pennsylvania and at higher altitudes.

I say this without having the data to back this up, but inferring from what we know of establishment of other crops such as small grains and alfalfa. There still remain questions about winter survival in the north and higher altitudes, particularly for crimson clover. In central PA hairy vetch and crimson have survived consistently in the past 7 years. However, both need to be planted by September 1 in central, and by September 15th in southern regions of Pennsylvania.

Crimson clover can fix some 80–100 lbs/A worth of nitrogen for next year’s corn or sorghum and hairy vetch can fix some 100–150 lbs/A worth. Crimson clover needs to be seeded at 15 lbs/A at ¼–½ inch depth. It grows quickly in the fall and comes on early in the spring. Its flowers will start appearing in mid-May in the south. The crop residue is quite stemmy and the no-till planter needs to be in top shape to cut through this to achieve a satisfactory stand.

Hairy vetch needs to be seeded at 20 lbs/A at ½–1½ inch depth and grows very slowly in the fall. It is therefore recommended to seed it with a nurse crop such as 2 bu/A of oats or 1 bu/A rye or wheat. The nurse crop will improve winter survival by offering some protection and also helps with soil erosion control and soil improvement. The vetch will start growing fast in April and continue its growth in May. The vetch residue is lush and viny and the planter also needs to be in top shape to plant through 1–2 tons of dry matter/A. Plan on terminating hairy vetch in the second week of May or later.

If you attempt to plant these legumes after corn silage harvest, pay close attention to the corn herbicide program used this past season. Many pre— and post—emergence herbicides may have residual activity after corn silage harvest, and may interfere with the establishment of the legumes.

Invasive Earthworms — Sjoerd Duiker, Soil Management Specialist

Invasive earthworms have been found in the forests of Latrobe, Westmoreland County. The earthworms belong to the genus Amynthas in the family Megascolecidae. The exact species has not been determined yet, but it is likely to be Amynthas agrestis. The earthworms are epigeic, or surface dwellers, so they typically live in the leaves or other organic debris on the soil surface. The earthworms are extremely active and can even be seen in broad sunlight.

The earthworm was apparently imported from Japan, probably in soil or plants. The species seems to spread quickly. Amynthas agrestis was observed in forests in northern Georgia as early as 1993, where it was found in much larger numbers than native earthworm species. The fear is that these new earthworm species will out-compete the natives in the natural landscapes.

In areas where earthworms are naturally absent (the glaciated regions of northern America, which includes the northwest and northeast of Pennsylvania), introduced earthworms tend to reduce the organic layer in the forest floor, and this has a whole cascade of effects on the food web of the forest. Depending on the type of earthworm, the forest floor may largely disappear, soil organic matter may be mixed with soil, and the whole soil profile may be modified as in the case of the night crawler (an introduction from Europe).

The major cause for concern with the invasive earthworms is in the natural areas. In our agricultural soils we usually consider earthworms to be beneficial, because they improve soil structure and stimulate decomposition of crop residue and the release of nutrients to the crop. However, as we learn more about earthworms we may also discover there is as much as too much of a good thing. In our no-till systems we value the mulch cover which gives us moisture conservation during the summer and the protection of erosion that come with no-till. If earthworms reduce the crop residue mulch too much they may actually reduce some of the benefits of no-till. Will the new earthworms invade our farm fields? We don’t know, but in continuous no-till soil where crop residue is constantly maintained they might find a home.

Crop Report from Northern PA — Mark Madden

2008 Northern-tier Crop Conditions Favorable

Not unlike the two previous years in the northern-tier, timely planting of most crops was possible for producers prepared to move when soil moisture was conducive to field work and planting. Given the short growing season and cooler northern climate, timely planting is particularly key for growers here. Rains to date have been sufficient to build expectations for very good corn yields. Forage yields have been good and feed quality measurements have given our dairy producers some encouragement over the coming year.

No widespread crop insect pest problems have been revealed in the northern-tier in 2008. Indeed, there have been isolated incidences of slugs, black cutworm and true armyworm in the corn but for the vast majority of acres, populations have been well below threshold. Rootworm beetle populations, yet to be counted, may suggest we should concern ourselves with management options for next year’s corn crop. Perhaps more noteworthy this year; however, is the alfalfa. Our most common pests with this crop, alfalfa weevil and potato leafhopper, have been relatively non-existent. It might be that favorable conditions and timely harvests have masked some of the damage but actual scouting counts are low. In the context of our current economic circumstances, a poor crop year could have been painful for some and disastrous for others. We’re hopeful August fills out our corn crop and we can get it off the fields in fine order.

Upcoming Events

Manure Haulers Spill Response Field Day
August 5, 2008
9 a.m. – 3 p.m.
At Lehman Ag Service, 300 Douts Hill Road, Holtwood, PA 17532
Don’t miss this opportunity to participate in a hands-on field day that will review safety issues of manure application including: safe equipment management, safe operational procedures, demonstration of over application response, first response demonstrations for accidents involving human injury and response procedures to manure spills. A spill response demonstration conducted at the end of the event will include a controlled manure tank roll-over and execution of clean—up procedures.
Certification Credits:
4.5 continuing education credits will be available for Commercial Manure Haulers and Brokers.
Questions?
Contact: Amy Bradford
(717) 651–5920 or abradford@pennag.com

The registration form can be downloaded by clicking on the following link. http://www.pennag.com/pdf/FieldDayRegistration.pdf

Ag Progress Days
Ag Progress Days, Pennsylvania’s largest outdoor agricultural exposition, will return for its annual three—day run, Aug. 19–21. Sponsored by Penn State’s College of Agricultural Sciences, the event is held at the Russell E. Larson Agricultural Research Center at Rock Springs, nine miles southwest of State College on Pa. Route 45.

Hours are: 9:00 am to 5:00 pm on Tuesday, August 19
9:00 am to 8:00 pm on Wednesday, August 20
9:00 am to 4:00 pm on Thursday, August 21
Visit the website at http://apd.psu.edu/

Hay Baling and Handling Meeting
September 3rd, Southeast PA Crops Conferences is again coordinating a fall equipment meeting.

This year we will be in the Lehigh Valley at Heidel Hollow Farm, Dave Fink and Family will be hosting the event. Don’t miss this opportunity to see and discuss big square balers, bale accumulators, stacker wagons and Fink’s large bale processing machine.

Click on the following link for the brochure, there is no fee to attend! Carpool with your neighbor, it will be an event you won’t want to miss. We will also have a session on the economics of this equipment.

Contributors: County Educators: Jeff Graybill, (Lancaster County), Andrew Frankenfield, (Montgomery County) Mena Hautau, (Berks County), Mark Madden, (Sullivan County), Jonathan Rotz, (Cumberland County), Department of Crop and Soil Sciences: Dwight Lingenfelter, Sjoerd Duiker, and Department of Entomology: John Tucker, Penn State

Editor:Paul H. Craig, Dauphin County.

Upcoming Events

Wednesday, February 10, 2010

Northeast PA No-Till Conference

Location: Harford Volunteer Fire Company, Harford, PA

Time: February 10, 2010

Details: Contact: Ryan Koch at ryan.koch@pa.usda.gov

Thursday, February 11, 2010

5th Annual North-Central PA No-Till Conference

Location: Bloomsburg, PA

Time: February 11, 2010

Details: Contact: Ryan Koch at ryan.koch@pa.usda.gov

Tuesday, February 16, 2010

Professional Crop Producers' Conference

Location: Holiday Inn, Grantville, PA

Time: February 16 and 17, 2010 (2 day event)

Details: The conference features Dwayne Beck from South Dakota on crop diversity in continuous no-tillage, Ray Archuleta with presentations on soil quality and nutrient management, and Charlie Sniffen on forages and animal nutrition. CCA CEUs will be available. Contact Sjoerd Duiker sduiker@psu.edu for more information.

Wednesday, February 17, 2010

Professional Crop Producers' Conference

Location: Holiday Inn, Grantville, PA

Time: February 16 and 17, 2010 (2 day event)

Thursday, February 25, 2010

Grazing School

Location: Berks County Agricultural Center, Leesport, PA

Time: February 25, March 4, March 11, 2010 — 7:00 pm to 9:00 pm (3 part series)

Details: Contact: Mena Hautau, +1-610-378-1327. This is a three-part series. You must attend all classes to receive credit. (4 Grazing)

Thursday, March 4, 2010

Grazing School

Location: Berks County Agricultural Center, Leesport, PA

Time: February 25, March 4, March 11, 2010 — 7:00 pm to 9:00 pm (3 part series)

Details: Contact: Mena Hautau, +1-610-378-1327. This is a three-part series. You must attend all classes to receive credit. (4 Grazing)

Thursday, March 11, 2010

Grazing School

Location: Berks County Agricultural Center, Leesport, PA

Time: February 25, March 4, March 11, 2010 — 7:00 pm to 9:00 pm (3 part series)

Details: Contact: Mena Hautau, +1-610-378-1327. This is a three-part series. You must attend all classes to receive credit. (4 Grazing)

Tuesday, March 16, 2010

Northwest Grazing Conference

Location: Dubois, PA

Time: March 16, 2010

Details: Contact Adam Dellinger at adam.dellinger@pa.usda.gov