CMEG Crop Management Extension Group

Field Crop News

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

August 25, 2009    Vol. 09:24

IN THIS ISSUE:

Weather Outlook — Paul Knight, Pennsylvania State Climatologist

A taste of late summer is likely on Wednesday as very warm and a bit more humid air streams into the state. Readings will touch 90F in parts of southeastern Pennsylvania. An approaching cold front in northwestern counties will trigger a late day or evening thunderstorm in about 20% of that region. As the front sags south across the state on Thursday, it will stall leaving the region with variable clouds and lower temperatures. The forecast becomes complicated for Friday and Saturday as a developing tropical storm is drawn northward near the Atlantic Seaboard. Depending on the track of the yet to be named storm (probably Danny), a pair of dull, drizzly days can be expected — should the storm stay offshore, or a damp Friday will be followed by a period of torrential rain in the eastern half of the state on Saturday (perhaps leading to flooding on some streams and rivers). Either way, a strong cold front will push the warm, moist air out to sea on Sunday and be followed by a touch of autumn for the first half of next week. It should be dry for much of next week with rather chilly mornings (30’s northern valleys, 40’s in the mountains and 50’s urban areas) on Tuesday and Wednesday. Another spell of warm weather should develop late next week.

Another very cool spell is likely during mid—September, with perhaps an unusually early end to the growing season in the northern counties. However, the latest indications point to a warmer than average September and October and perhaps a late start to wintry weather, especially near the Great Lakes. The development of a moderate El Nino in the Pacific portends a wetter winter (and probably snowier) in the state.

Managing Burcucumber Late Season in Corn and Soybeans — Bill Curran, PSU Weed Science Specialist

With the wet weather we have been experiencing this summer, conditions are perfect for late season burcucumber problems in corn and soybean. Under these conditions, burcucumber continues to germinate and emerge late into the season and it’s not until it gets above the crop canopy that it is often noticed. This late in corn, there are few options for managing this troublesome weed. Some products with burcucumber activity may be applied up to pre—tassel (Beacon) or tassel (Buctril) or do not have any restrictions (Basagran). Impact can be applied up to 45 days before harvest and may have the best chance of reducing seed production which is generally taking place now up until frost. In addition, 2,4–D LVE may be used after hard dough stage, glyphosate when corn grain is 35% moisture or less, and Gramoxone Inteon after black layer or dent stage. These pre—harvest applications are targeting grain production prior to a frost and really are intended just to allow combine harvest of the crop. Gramoxone is probably the most effective of these three options.

In soybean, glyphosate may be applied to Roundup Ready soybeans through flowering (R2 stage) for late season control. For pre—harvest, glyphosate may be applied to Roundup Ready and conventional soybeans after 80% leaf drop (loss of all green color), Gramoxone when soybean grain is 30% moisture or less or 65% or more of the seed pods have reached a mature brown color, and Clarity may be used once pods have reached a mature brown color and at least 75% leaf drop. Again, Gramoxone is probably the most effective of these treatments.

Finally, if burcucumber can be harvested for silage and the seeds are immature or still green, the ensiling process will kill the seeds. If the corn or soybean is harvested for grain, the mature seeds will simply end up back in the field making the problem worse for future years.

Herbicide Persistence and Late Summer/Fall Cover Crop Establishment — Bill Curran and Dwight Lingenfelter, PSU Weed Science

As we contemplate late summer cover crop establishment, remember that your spring herbicide program may limit your options. Most herbicide labels only include the major cash crops in their rotational information and do not provide specific details about what cover crops can be planted after an herbicide treatment earlier in the season. Cereal rye, wheat, barley and oats are four common crops that are often listed on a product label. Refer to the Agronomy Guide Tables 2.2–17 and 2.4–15 or the herbicide label to determine which products have ≤4 month rotation restriction for covers such as rye, field pea, clover, oats, and sorghum/sudan. There is no listing for hairy vetch and some of the more obscure clovers/legumes, but by looking at the alfalfa or clover restrictions you can get a good idea of which herbicides may cause potential injury. Covers such as canola/rape, tillage radish, and buckwheat can be difficult to determine if herbicide residuals will cause problems. In general for corn herbicides, atrazine at less than 1 lb/A can allow cereal grain establishment and at less than 0.75 lb/A may allow for most legume cover crops, mustards, and annual ryegrass. This should be similar for simazine (Princep). In addition to atrazine and simazine, mesotrione (Callisto and a component of Lumax/Lexar) is problematic for legumes and probably mustards like canola, and clopyralid (Stinger and a component of Hornet and SureStart) could also affect these small seeded broadleaves.

For soybean herbicides, chlorimuron (Canopy, Classic, Envive, Synchrony, etc.), Pursuit or Extreme, and Prefix or Reflex could be a problem for fall seeded legume or mustard cover crops, but cereal grains should be OK. Persistence of some of the other corn and soybean herbicides and their impact on legumes or mustard species in particular is less clear. Until more research is conducted assessing specific herbicide—cover crop interactions, the general guidelines provided in Agronomy Guide Tables 2.2–17 and 2.4–15 can be helpful.

Numbers and Quality Low at PFGC Hay Show — Marvin Hall, PSU Forage Specialist

This year’s PFGC Hay Show at Ag Progress Days had the fewest number of entries in since 2004. The total number of entries (102) was about 40 fewer than entered the show last year. These low numbers are a direct reflection of the poor hay making weather that we have had in some areas of the state this year.

The visual appearance of the samples that were entered in the Hay Show looked good but not excellent and this was reflected in the chemical analysis for quality. Averaged across all samples crude protein was 16.4, acid detergent fiber (ADF) was 37, neutral detergent fiber (NDF) was 53, and relative feed value (calculated from ADF and NDF) was 111. Numerous exhibitors and visitors at the Hay Show mentioned that rainy weather made hay making nearly impossible this year.

The Champion in the field—cured division was Randy Ziegler from Fredericksburg, PA in Lebanon County with an entry of later cut alfalfa hay. The Champion in the heat—dried division was Bieber Newhard Farms from Nazareth, PA in Northampton County with an entry of later cut alfalfa. The Champion in the preservative division was Nevin Rice & Son from Blain, PA in Northampton County with a later cutting alfalfa sample.

Time Running Out for Fall Forage Seeding — Marvin Hall, PSU Forage Specialist

Farmers are frequently faced with the situation of planting perennial cool—season forage crops later in the fall than is recommended. The risks of planting late must be weighed against the need for forage the following year or the need for ground cover to comply with conservation plans. These are strong pressures on producers to assume greater risk and plant after the recommended latest date. Research conducted in Centre and Lancaster Counties examined the effects of fall seeding date on stand vigor and yield of alfalfa, red clover, birdsfoot trefoil, orchardgrass, perennial ryegrass and reed canarygrass.

Delays in forage legume planting after August 1 reduced plant height in late—November, percent of row occupied by the forage species in the spring after planting, and DM yield during the year after planting. Each day planting is delayed after Aug. 1, total DM yields for the year after planting were reduced by an average of 158 and 116 lb/acre/day for alfalfa, 105 and 71 lb/acre/day for red clover, and 76 and 28 lb/acre/day for birdsfoot trefoil in central and southern Pennsylvania, respectively. Averaged over both locations, planting after August 1 reduced plant vigor and total yield (average of 0.5, 0.25, and 0.2 ton/acre/week for alfalfa, red clover, and birdsfoot trefoil, respectively) the year after planting. Generally, planting legumes after September 5 in central and October 10 in southern Pennsylvania resulted in total DM yields of less than one ton/acre during the year after planting.

Planting orchardgrass and perennial ryegrass after August 1 reduced plant height in late—November and plant vigor in the spring after planting. However, DM yields during the year after planting did not begin to decline until planting after Sept. 1. In fact, total DM yields for the year after planting were 30% greater when perennial ryegrass was planted in late-August compared to early—August. On average planting delays of orchardgrass and perennial ryegrass after Sept. 1 resulted in average total DM yield declines the following year of 94 and 134 lb/acre/day, respectively. Unlike orchardgrass and perennial ryegrass, when reed canarygrass planting was delayed after early—August yields were reduced by an average of 91 lb/acre/day.

Summary: Perennial cool—season forage plantings can persist through the winter if planted within a few weeks after the recommended optimum date (mid—August in the central region through early—September in the southern region of Pennsylvania). However, adequate consideration should be given to the reduction in plant vigor and yield as a result of delaying planting. In general, planting perennial cool—season forage crops after September 5 in central and October 10 in southern regions of Pennsylvania severely jeopardized the winter survival of the seedlings and resulted in yields that are too low for forage harvesting.

Silo Sickness: Protect Yourself from Respiratory Troubles — Joel Hunter, Extension Educator, Crawford County

Unfortunately, each year calls come in, generally from a family member, concerned that a loved one is suffering from severe flu—like symptoms (especially aches and pains) after working in the silo. Often, it’s more than one person involved, and the severity and duration of the symptoms are frequently proportional to the exposure time that occurred. The vast majority of farmers are aware of the deadly dangers of silo gases and hopefully all take appropriate measures to avoid silo gases. However, all too frequently, exposure to molds and dusts occur because proper respiratory protection is not used. An acute exposure may involve inhalation of hundreds of thousands or even millions of tiny spores, causing a condition referred to as Organic Dust Toxicity Syndrome (ODTS) or Silo Unloaders’ Syndrome. With repeated exposures over time, a chronic condition, which can include actual scarring of lung tissue, can develop and is commonly referred to as Farmer’s Lung. The four links below are a sampling of the information that has been presented to inform, educate, and prevent such respiratory troubles among farm workers. Take the time to look them over and share them family members and workers. The bottom line is simple and straight forward, farmers need to use caution and respiratory protection to limit their exposure to dusts and molds. So, in addition to the seemingly more maligned dangers of silo gases and potential fatalities, please also take the necessary precautions of avoiding/reducing exposure to molds and dusts thereby preventing the associated potential acute and chronic respiratory illnesses that they can cause. Related links for additional information and details:

http://www.nycamh.com/resources/brochures/pdfs/respiratory.pdf

http://www.abe.psu.edu/extension/factsheets/e/E26.pdf

http://www.nasdonline.org/docs/d001001-d001100/d001027/d001027.html

http://pubs.ext.vt.edu/442/442-602/442-602.html

Winter Canola Possibilities — Greg Roth PSU Grain Crop Management Specialist

The combination of high prices for oilseeds and relatively low prices for winter wheat have created an interesting situation where canola appears to be a potentially more profitable crop than winter wheat, even when considering the value of the straw. A big issue is that there are only limited markets for winter canola in the state, but with the increased interest in oilseed processing in the state there could be more opportunities for winter canola production than in previous years.

One of the key issues with winter canola is to plant the crop on a timely basis to avoid winterkill. Winter canola should be planted in late summer to ensure adequate growth before winter. Ideally plants should have 6 leaves and a taproot the size of a pencil before the first killing frost. In central Pennsylvania, seeding from Sept 1 to 15 is a good target. In longer season areas in the southern part of the state, planting can continue through the end of September. We have done both tilled and no—till establishment and have had good success with both except in high residue no—till situations. Canola is a bit more risky than small grains to establish, but we have generally had good success. It also compensates very well if the stand is thin.

Both conventional and glyphosate—resistant varieties are available for winter canola from several different firms in the state. Our variety test conducted in 2008 lists several suppliers of seed. Since then other suppliers have started handling winter canola as well. Yields in that test ranged for 40 to 66 bushels per acre. Our low yielding site lodged, or we would have had an even higher yield. A reasonable yield target is 50 bushels per acre. Our variety testing data, a draft Penn State Factsheet on canola and a link to an Oklahoma State winter canola production factsheet is located on our Renewable Energy canola website: http://webdev4.agsci.psu.edu/energy/field-crops/canola

We have not established official canola fertility recommendations yet, but typical recommendations are about 100–60–60 for a 60 bu/a crop. In production fields near campus, we have had good success harvesting with conventional small grain combines and often the crop requires minimal air drying for storage. Timely harvest is important to avoid shattering in the crop. So far, we have not experienced much deer damage to the crop, even though we have grown it in areas with some deer pressure.

Upcoming Events — Mark Your Calendar

2010 Tri—State and Southwest No—Till Conferences
Featuring: no—till farmer, David Brandt; soil fertility specialist, Doug Beegle; and forage extension educator, Paul Craig
Tuesday, February 2, 2010
(Tri—State — Radisson Hotel, West Middlesex)
For more information, contact Ed Petrus 724–662–3740 Ext. 101
Wednesday, February 3, 2010
(Southwest — Giannilli’s II, Route 30 East of Greensburg)
For more information, contact Sherene Hess 724–853–5555 Ext. 116

Contributors:: Extension Educators: Joel Hunter (Crawford), Susan Alexander (Jefferson), Greg Hostetter (Juniata), and Bill Waltman (Potter). State Specialists: Bill Curran, Marvin Hall, Sjoerd Duiker, Doug Beegle, Greg Roth, and Dwight Lingenfelter.

Editor: Dwight Lingenfelter, PSU Extension Agronomist — Weed Science

Upcoming Events

Real time pest and heat unit activity: http://agsci.psu.edu/news/spotlight/pa-pipe

Calendar of Events: http://www.events.psu.edu/cgi-bin/cal/webevent.cgi?cmd=opencal&cal=cal209&

If you have any questions or would like to suggest a topic, please contact your local Extension Educator.

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