FCN Logo College of Agricultural Sciences Penn State

May 21, 1999 Vol. 99.4

IN THIS ISSUE:

Mark Your Calendar

Production

Pest Management

Agents Corner

Degree Day Accumulations

Largest Weed in Pennsylvania Contest

Production:

TOUR OF WINTER GRAIN VARIETY TRIALS

On June 10 at 1:00 p.m. we are offering a tour of the winter grain variety trials at the Penn State research farm in Landisville, PA. Dr. Marvin Risius, Professor of Plant Breeding, will be there to discuss the trials. You will have the opportunity to observe both old and new releases of winter barley and winter wheat as well as advanced breeding lines. Certified Crop Advisor CEU's will be provided.

Elwood Hatley, CCA
Agronomy, Small Grains



WATER QUALITY FIELD DAY

A tour of the Pequea-Mill Creek Hydrologic Unit Area Project for staff from agencies, conservation districts, and cooperative extension interested in water quality is planned for Thursday, June 24, 1999 (rain or shine) from 9 am to 3 pm, leaving from and returning to the Bird-In-Hand Restaurant, Bird-In-Hand, PA. Lunch will be on your own at a local Pennsylvania Dutch eatery.

You will see some of the key water quality protection practices and learn about the experiences of the project team in working with farmers, ag professionals and special interest groups, including environmental and wildlife organizations. The practices to be highlighted include streambank fencing and bioengineering, barnyard management, rotational lot management systems, and pesticide storage and handling. We will be joined by other agency specialists who have contributed to the project goals or are evaluating the effectivenss of various practices. You will learn helpful lessons about the promotion of water quality protection in an intensive agricultural watershed.

Please notify the Pequea-Mill Creek Project staff at (717) 396-9423 if you will be attending by June 14, 1999, so arrangements can be made for transportation during the tour and reservations at the lunch stop.

Les Lanyon, Agronomy, Soil Fertility

WHAT'S HAPPENING IN CORN RESEARCH?

We have lots of interesting trials going on this year and since we are having such a great planting season with few problems, I thought this might be a good time to share some of what's happening in our research program.

In one set of trials we're looking at starter fertilizers. Several states have shown advantages of 2-1-0 and 1-1-0 liquid starter blends on no-till corn on high P and K soils compared to conventional 1-2-1 and 1-3-1 starter blends that are common in Pennsylvania. These starters would be more economical as well. We've got two trials planted this spring to look at yield and other issues, like the need for sulfur, associated with starters.

We're cooperating with six other states in a yield comparison study of 6 Roundup Readyä corns and their isolines. Industry data suggests any yield drag should be minimal. This trial will give us some good independent data to confirm that.

We are looking at the potential for higher plant populations with new normal and Bt hybrids. In our Five Acre Corn Club, participants have been increasing plant populations by 250 plants per year for the last 20 years, averaging 26,000 plants per acre last year. My counterparts in New York and Illinois have reported maximum grain yields at plant populations in the 28,000 to 30,000 range. Our results from two trials last year seem to confirm this response in Pennsylvania as well. We have two population trials in the ground again this year.

We're also looking at the population response for silage corn, measuring both yield and quality. We're doing this in both narrow and wide rows. In three trials last year, yields increased to 30,000, 36,000 or 42,000 plants per acre, depending on the trial and the hybrid, while quality either declined or remained constant above 30,000 plants per acre. The benefit of the narrow rows was about 5%. This response is consistent with about 15 other narrow row trials we have conducted to date and with much of the data on this topic from Dr. Bill Cox at Cornell.

We are also planting another trial to compare the agronomics and feed quality of a brown midrib forage sorghum compared to a normal forage sorghum and corn. Other university data suggests the feed quality of brown midrib sorghum is superior to normal forage sorghum but it may lodge more than normal sorghum.

Your input on what we're doing is always valuable. Comments, criticism, suggestions and, oh yes, additional financial support are always welcome regarding our research.

Greg Roth, Agronomy,
Corn and Sorghum Management

Pest Management:

CORN HERBICIDE APPLICATION TIMINGS: DEFINED?!?

In the past there were generally two or three times when herbicides were applied in corn - preplant, pre or postemergence. Now with more and newer products, post application timings in particular are being subdivided into different timings (i.e., delayed pre, early post, mid post, post, late post, etc.). Unfortunately there are no exact definitions for these various timings. In general, the standard preplant, pre, and post definitions are adequate for most products, but if you would like to remain on the cutting edge of herbicide application lingo, please read on. Below are some general guidelines to follow, based on our opinion (Table 1). Keep in mind, these definitions may vary between parties, so always refer to the product label for the proper application timing with respect to corn and weed growth stages.

Table 1. Herbicide application timings with respect to corn and weed growth stages and weeks after planting.
Application
timing		 Number of
corn leavesa		 Number of
corn collarsb		 Average
corn heightc		 Weed
height		 WAPd Example
Preplant 0 0 0 0 0 Typical of standard preplant or preemergence applications such as Bicep, Harness Xtra, Guardsman, Full-Time, etc.
Pre 0 0 0 0 - 2 inches 0 to 1 Typical of standard preplant or preemergence applications such as Bicep, Harness Xtra, Guardsman, Full-Time etc.
Delayed pre 0 0 <1 inch 0 to 2 inches 7 to 10 days Ideal application timing for Prowl. Other products can vary, see label.
Spike 1 (tightly wrapped) 0 <2 inches 0 to 2 inches 1 to 3 Typical application timing for Prowl
Early post 1 to 3 <2 <6 inches <3 inches 2 to 4 Ideal application timing for Banvel, Clarity, and Basis
Mid post 3 to 6 2 to 4 Up to 12 inches 2 to 6 inches 3 to 5 Typical of many post applications (Exceed, Basis Gold, Accent, etc.)
Post May encompass early, mid and late post applications
Late post
(not split) 		7 to 11 5 to 9 12 to 20 inches 8 to 12 inches 7 to 8 Typical of many applications. Later timings generally not recommended except as a rescue
Late post
(as split treatment) 		7 to 11 5 to 9 12 to 20 inches 2 to 6 inches 7 to 8 May be the second application of Roundup in Roundup Ready corn or Liberty in glufosinate resistant corn.
Layby
(use drop nozzles) 		11 to 13 9 to10 20 to 36 inches Varies 8 to 9 Layby refers to an application at the last cultivation time or the equivalent.
a number of leaves with greater than 50% of leaf exposed
b number of leaf collars fully exposed
c Average corn height measured to the arch of the highest leaf that is >50% emerged
d WAP= weeks after planting


HERBICIDE PERFORMANCE AND LACK OF RAINFALL

Dry weather can affect both soil applied and postemergence herbicide performance. All soil applied herbicides require rainfall to mobilize them for effective weed control. In general, rainfall should occur within 7 to 10 days after application or before weed emergence. As a general rule of thumb, 1/2 inch of rain is considered the minimum depending on current soil moisture levels and the herbicide used. The less mobile materials (Prowl, Atrazine, Scepter) and deeper germinating weeds (e.g. yellow nutsedge, cocklebur, velvetleaf, ragweed, etc.) will require even more rainfall for effective control.

If the 10 day limit has gone following a Pre treatment and weeds are starting to break, consider using a rotary hoe, making a post herbicide application, or start tuning up that old cultivator that you have been dying to try again.

Although some "reach back" can be expected on small annual weeds (esp. broadleaves) with some herbicides when rainfall occurs, depending on this is a little like gambling in Las Vegas. As for post herbicide applications, remember that small annual weeds are easier to kill than large ones and examine adjuvant options to maximize activity under dry weather conditions. Delaying the herbicide application until after a rainfall rarely increases your chances of success unless you're making that decision while watching a large storm front move in from the west.


POSTEMERGENCE HERBICIDE USE IN SOYBEANS

Table 2. Herbicide application rates, weeds controlled, spray additives, rainfastness, and application timings for postemergence soybean herbicides.
Herbicide Application rate (product/A) Weeds controlled Adjuvant(s)1 Rain fastness (hours) Application timing2
Assure II 5-10 fl oz G NIS or COC 1 80 days before harvest and not after pod set
Basagran 1.5-2 pt B, N COC or VOC or UAN or AMS (for velvetleaf) 8 No statement
Blazer 0.5-1.5 pt B NIS or UAN (for velvetleaf) 6 1-2 trifoliate to 50 days before harvest
Classic 0.5-0.75 oz B, N NIS or COC plus UAN or AMS (for velvetleaf) 1 1 trifoliate to 60 days before harvest
Cobra3 6-12.5 fl oz B NIS or COC plus/or UAN or AMS 0.5 1-2 trifoliate to 45 days before harvest
Concert SP 0.5 oz (1 pack/4 acres) B NIS or COC plus UAN or 10-34-0 or AMS 1 1 full trifoliate to 60 days before harvest
FirstRate 0.3 oz B NIS plus UAN or AMS or COC or COC plus UAN (optional) 2 1 trifoliate to 65 days before harvest
Fusilade DX 6-12 fl oz G NIS or COC plus UAN or 10-34-0 (optional) 1 Prior to bloom
Fusion 6-10 fl oz G NIS or COC plus UAN (optional) 1 Prior to bloom
Pinnacle4 0.25 oz B NIS or COC plus UAN or AMS (for velvetleaf) 1 1 trifoliate to 60 days before harvest
Poast
or
Poast Plus6 		0.75-1.5 pt
or
18-36 fl oz 		G COC or VOC or Dash HC plus UAN or AMS (for certain species) 1 75 days before harvest
Pursuit 2S
or
70DG 		4 fl oz
or
1.44 oz 		B, G NIS or COC or VOC plus UAN or AMS 1 85 days before harvest and prior to bloom
Raptor 4-5 fl oz B, G COC or VOC or NIS plus UAN or AMS 1 85 days before harvest and prior to bloom
Reflex
or
Flexstar 		1-1.5 pt B NIS or COC plus UAN or AMS (optional) 1 Prior to bloom
Resource 4-12 fl oz B COC plus UAN (optional) 1 60 days before harvest and not after pod set
Roundup Ultra5 16-64 fl oz G, B, N no NIS or COC required; AMS (optional) 1-2 soybean emergence through flowering
Scepter 1.5S or 70DG 0.66 pt
or
2.8 oz 		B, G NIS or COC 1 90 days before harvest
Select 6-16 fl oz G COC plus UAN (optional) 1 60 days before harvest
Stellar 5-7 fl oz B COC or VOC plus UAN or AMS (optional) 1 60 days before harvest and not after pod set
Storm6 1.5 pt B NIS or COC or UAN or AMS (for velvetleaf or pigweed) 8 2-3 trifoliate to 50 days before harvest
Synchrony STS 42DF7 0.5 oz (1 pack/4 acres) B, N COC plus UAN or 10-34-0 or AMS (for velvetleaf) 1 1 full trifoliate to 60 days before harvest
B=broadleaves, G=grasses, N=yellow nutsedge
1 In general, nonionic surfactants should contain at least 80% surface active agent; crop (COC) or vegetable (VOC) oil concentrates should be non-phytotoxic containing at least 15% approved emulsifier; nitrogen solution (UAN) is ammonium based fertilizer such as 28%, 30%, or 32% N; and ammonium sulfate (AMS) should be spray grade dry ammonium sulfate (21-0-0). 10-34-0 may also be used with some products. In general, unless otherwise directed by label, NIS should be included in the spray tank at 0.25% v/v (1 qt/100 gal), COC at 1% v/v (1 gal/100 gal), UAN at 2 qt/acre, and AMS at 3 lb/acre.
2 Earliest applications should be made when weeds are most susceptible to herbicide (refer to product label), otherwise apply at or after earliest soybean stage specified.
3 Adjuvants for use with Cobra depended on relative humidity and weed species.
4 Use crop oil concentrate under drought-stressed conditions.
5 For use on Roundup Ready soybean varieties only.
6 For Poast Plus with Storm in a tank-mixture, include 1 gal/100 gal of crop oil concentrate.
7 For use on STS soybean varieties only.

Postemergence herbicide programs are becoming widely used and can provide an effective weed control option. When using a POST program consider crop and weed size, necessary adjuvant(s) and rate, rainfastness, and application timing restrictions; see Table 2 for more information. Tank mixing not only broadens the control spectrum, but also is generally necessary for planned POST programs. Keep in mind that certain tank-mix combinations may cause antagonism. In most cases, grass control is reduced when a broadleaf plus grass herbicide mixture is used. To overcome this problem either increase the grass herbicide rate or apply the broadleaf product a day or two after applying the grass herbicide. See current herbicide label(s) for additional information on herbicide application information and precautions.

Dwight Lingenfelter and Bill Curran Agronomy, Weed Science

Agents Corner:


ARMSTRONG/INDIANA/WESTMORELAND COUNTIES

With the exception of a recent thunderstorm, the region has been very dry this spring. Soil probe samples of 8 to 12 inches reveal very little moisture below the topsoil. Corn planting is in full swing, and a few farmers have begun planting soybeans. One producer in the region had planted 750 acres of corn as of May 6. Many others were also on target this spring with timely corn planting.

Due to some much needed rain in late March and early April, oats, spring barley, and spring seeded forage stands were delayed in planting. Many farmers in the area were still seeding small grains in early May. Mildew in small grains has not been a factor this year.

Pasture growth has been slow due to dry weather. Many local farmers say that the forage crops are a week ahead of "normal". I would agree, as I saw an orchardgrass plant in head on April 30, with most of the orchardgrass stands now in full head. At least one stocker cattle producer has reduced the number of animals he will graze this year due to lack of pasture growth.

Alfalfa stands have had some problems, due to insect, disease, and deer pressure. Alfalfa weevil is present in many stands throughout the tri-county area, and clover root curculio damage is evident on the roots. White-tailed deer are over-abundant in SW Pennsylvania, and are causing damage in alfalfa and winter wheat fields. But they will soon move to the soybeans, allowing for some second cutting alfalfa (we hope).

On April 23 I was in southern Westmoreland County, and the alfalfa-grass hay fields looked very promising, as pest pressures were not as evident. In fact, these forage stands could have been harvested at ideal maturity in early May without much difficulty from the weather. A couple dairy farmers had first cutting laying this week, ready to be ensiled, but most have yet to begin first harvest.

Robert Stout
Armstrong County

CLEARFIELD/JEFFERSON COUNTIES

The planting of crops is ahead of previous years due to the warm, dry weather. Producers are busy making use of the days to get their crops planted. Some farms will be planting a few acres of soybeans once they are finished with their corn acreage. Oats are up and doing well. The much needed rain of early May helped give the pastures and hay fields a good boost in their growth.

Unfortunately, there is still a shortage of moisture. In fact, I have had a report of a spring going dry the middle of May and stream levels are not what they should be for this time of the year.

Susan Alexander
Clearfield/Jefferson Counties

CRAWFORD/ERIE COUNTIES

Drier than normal soil conditions coupled with a rather moderate winter seem to have brought perennial forages and winter cereal grains through dormancy in good shape. The start of the 1999 growing season in Northwestern Pennsylvania has been unusually good. I am pleased to report that both fall and spring conditions were favorable for lime applications, and many producers, to their credit, apparently took advantage of that situation. Soil conditions have been good for working ground since March with the exception of about one week in April. Both soil and air temperatures have been higher than normal with only a few nights since mid-April where temperatures dropped into the higher twenties.

These favorable early season conditions have provided producers with opportunities for both early and timely forage and spring cereal grain plantings. Intensively managed cool-season grasses do seem to be getting more due consideration as an alternative to alfalfa on our considerable acreage of less than well drained soils in the region. For the second year in a row, the timing for the first cutting of high-quality, nitrogen-fertilized grasses in the region demanded early May harvesting as opposed to the more typical mid-May timing. Of course, the need for staying on top of management in this system is nothing new, but the rewards are well worth the effort. First cutting of alfalfa and mixed forage stands are just now getting underway. In some cases, some quality has already likely been sacrificed.

The favorable weather conditions have also provided some excellent opportunities to get an earlier than normal start on corn and soybean plantings. Some producers, especially in the southern areas of the region, even got started in mid-April, which is obviously very early (and normally very risky) for us, but it appears that it just might work out for us this season (although we've still got to get by the full moon towards the end of the month). Soil temperatures, even in reduced tillage systems, seemed to hit the 50 degree mark as early as late April. And although soil moisture was fairly limited, corn planted in early May was germinating and emerging in about a week to ten days on average. Coupled with consistent high winds and dry soils, these conditions are making effective pre-emergence herbicide programs a challenge this season. However, a significant front that moved through the region late yesterday and through the night brought nearly an inch of badly needed moisture to most parts of the region which should hopefully help.

Zone tillage of both corn and soybean continues to increase throughout the region. The system seems to be working out well for the region with fairly consistent adoption and acceptance among a growing number of producers each year. Implementation of reduced reduced tillage system in the region is welcomed and long overdue. Another practice that has captured the interest of a number of producers in the region is the use of higher nitrogen rates (40 to 60 units of N per acre) for starter materials. The theory for this practice may have some potential merit in our normally cold and wet early season conditions, and some field evaluations are of great interest. However, with the warm and relatively dry conditions thus far this season, the "jury may still be out" for a few more seasons. Along these same lines, I continue to be quite concerned with the apparent willingness of some to use urea and DAP in starter materials as opposed to the recommended ammonium nitrate, ammonium sulfate, and MAP materials for insured safety against corn injury. There would seem to be a possibility that the relatively drier conditions this year may provide a lesson the "hard way" in this regard this season.

All in all, we are off to a good start in Northwestern PA, but we're hoping to get soil moisture levels back up to a more comfortable level before to long. We'll keep you posted. Best wishes for a great season to all.

Joel Hunter, CCA
Crawford County

DAUPHIN COUNTY

Until the past week, the spring in Dauphin County had been relatively dry and cool. In spite of the cooler than normal soils much of the corn has been planted and soybean planting is progressing. The corn that is up looks good. In addition, much of the rye has been cut. There have been several reports of the presence of weevils in some alfalfa fields. However, all fields that I checked seem to have minimal damage and larvae numbers below economic thresholds. A few farmers are planning earlier than normal cuttings in light of this.

Hay fields and pastures have not grown as normal due to cool, dry weather. Dauphin County received .6 to 1 inch of much needed rain over the May 1 weekend. This rain, coupled with warmer temperatures, has caused hay and pasture growth to pick up significantly. Hay harvest is in full swing in all parts of the county.

Jerry Martin
Dauphin County

LYCOMING COUNTY

The corn crop is mostly in the ground at this point other then the fields that will be planted after the first cut of alfalfa. Emergence is good with weed pressure just now starting to show up. Soybeans are about 1/3 planted but I haven't seen any coming out of the ground at this point. Some soils are getting crusted due to the lack of recent rains which is starting to concern a few producers. Officially we are below normal rainfall in the area but we have plenty of time left this spring to make this up. The clear weather has however been real positive for getting the multitude of spring jobs completed.

Alfalfa growth is spotty in the county with drier areas and shorter growth showing up. Overall though, the crop looks good to excellent with few insect pest problems observed and much of the crop being cut now that the corn is planted. The grass hay crop is shorter than last year at this point and I would expect yields to be average or less when the first cut is taken off. The drier weather has produced less disease pressure in the small grain crop so far but the height of the grain plant looks good at this point.

Tom Murphy
Lycoming County

WAYNE COUNTY

Dry, windy conditions during April and early May have us all thinking this is a repeat of the 1998 growing season. The similarities between the two Springs are amazing. Hopefully 1999 will turn out to be a better year than 1998 but we'll need some rain to make that happen. Corn planting in the region is progressing well ahead of schedule. Many producers are finishing up their planting duties, which is probably a week or so ahead of normal. Soil temperatures are in the mid 50's which is unheard of for mid May in Northeastern PA. Corn has spiked through the ground within seven days after planting which is also unheard of for us in mid May. I anticipate uneven emergence in some fields due to prolonged dry soil conditions after planting. No pest problems have been observed or reported yet.

Most of the orchardgrass (our primary forage crop) in Wayne County is in the boot stage or just starting to head out. In other words, IT'S TIME TO CUT! The dry Spring has dramatically affected our hay crop. First cutting yields are expected to be 1/2 to 2/3 of a normal harvest. Several of the "early birds" have started haying and will be putting up a high quality forage; although most producers are anticipating a more traditional early to mid June harvest. Incidentally, a random sampling of last year's first cutting indicated crude protein values of around 20% for mid May harvested orchardgrass. Mid June harvested orchardgrass averaged 12% CP.

Dave Messersmith
Wayne County

Degree Day Accumulations:

1999 DEGREE DAY ACCUMULATIONS

To track corn and insect development, compare the 1999 cumulative degree-days shown in Table 3 to the required values in Tables 4 and 5. Choose a location that is closest to your site when making a comparison.

Table 3. Cumulative Degree Days for Corn and Insects for the Period Ending May 21, 1999
Corn Insects
County Location 1999 30-year ave. SCM/SB AW BCW CRW ECB
50F 50F Diff 40F 48F 50F 53F 55F
Erie Waterford 162 127 35 657 311 246 166 125
Crawford Meadville 168 136 32 717 340 272 186 140
Mercer Mercer 169 138 31 736 349 279 193 146
Bradford Towanda 165 134 31 710 330 261 175 131
Lycoming Montoursville 172 144 28 788 368 294 201 151
Tioga Mansfield 159 126 33 656 305 239 160 119
Susquehanna Montrose 151 115 36 596 273 213 140 103
Butler Butler 175 146 29 800 381 305 213 162
Indiana Indiana 174 145 28 803 380 305 212 161
Lawrence Lawrence Jct 169 137 32 713 339 271 185 140
Blair Martinsburg 170 141 29 782 368 294 203 154
Centre State College 168 139 29 758 355 283 194 146
Columbia Bloomsburg 174 147 27 814 379 303 208 157
Clearfield Curwensville 168 138 30 744 350 278 191 144
Dauphin Elizabethville 178 152 26 866 406 325 226 171
Bedford Bedford 177 151 26 863 409 328 229 176
Mifflin Belleville 175 148 27 828 389 312 216 164
Northumberland Sunbury 178 152 26 856 401 321 222 168
Lehigh Trexlertown 179 154 25 893 417 333 231 175
Schuylkill Hegins 174 147 27 825 385 307 212 160
Westmoreland Greensburg 174 146 28 817 388 311 217 166
Somerset Somerset 162 128 33 711 335 267 183 139
Washington Washington 181 155 26 881 423 340 240 185
Franklin Chambersburg 184 160 23 947 450 361 254 195
York York 186 164 22 989 470 376 265 204
Lancaster Ephrata 180 155 24 907 425 340 237 180
Berks Hamburg 180 156 24 905 424 339 236 179
Corn degree-days based on a May 1 starting date. Insect degree-days based on a January 1 starting date.


Table 4. Cumulative Degree-Days Required for Insects to Reach key Periods for Scouting or Management
  Maturity rating (days)
80 90 100 110 120
50% Silking 1100 1150 1250 1300 1400
Black Layer Formation 1900 2100 2300 2500 2800


Table 5. Cumulative Degree-Days Required for Insects to Reach key Periods for Scouting or Management
  Stalk Borer Alfalfa Weevil Black Cutworm* Corn Rootworm European Corn Borer Seed Corn Maggot
Adlt Emrg 5% Hatch 1st Gen 2nd Gen
SB AW BCW CRW ECB1 ECB2  
Initiation 1400 300 91 1283 380 WCRW** 558 1550 450***
Termination 1700 500 430 2253 478 NCRW** 1228 2045  

*Degree-day accumulation should begin at first moth capture in a black light or pheromone trap.
**These values represent degree day accumulations for optimal timing of Furadan 4F post emergence applications. WCRW-Western Corn Rootworm, NCRW-Northern Corn Rootworm
***This number of degree days represents the number of degree days required from plowdown of green vegetation until it is safe to plant corn or soybeans and avoid seed corn maggot injury.

Dennis Calvin, Entomology

William S. Curran
Associate Professor Weed Science
email: wsc2@psu.edu

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