FCN Logo College of Agricultural Sciences Penn State

June 18, 1999 Vol. 99.6

IN THIS ISSUE:

Mark Your Calendar

Production

Pest Management

Agents Corner

Degree Day Accumulations

WEED TOUR QUICKLY APPROACHING

Don't forget to register for the 1999 Weed Tour on July 13 at Rock Springs. Return registration form contained in the last issue of the Field Crop News (June 4, 1999, Vol. 99:5) or call Lisa Crytser at 814-865-2543 to register or for additional information.

Production:

NITROGEN AVAILABILITY FROM MANURE APPLIED ON GRASS HAY FIELDS

Grasses are especially well suited to manure application because they have a high demand for all of the major nutrients in manure. Grasses, unlike legumes, require regular applications of nitrogen for optimum production. The general recommendation is 40 lbs. of nitrogen per ton of expected yield per acre. Rates of manure application to grasses should be based separate applications meeting this nitrogen requirement for each cutting of the grass. This means that manure applications to grass should split up to meet the requirements of the next cutting of the grass. The rate must also be low enough so that the stand is not physically damaged by the application. When calculating the manure application rate based on nitrogen, the nitrogen availability of the manure must be considered. The amount of available nitrogen will depend on the type of manure, the time of year, and how long it will be exposed on the surface before it receives 1/2 inch of rainfall. Factors for estimating N availability for grasses are given in the Penn State Agronomy Guide.

There has been some confusion about what nitrogen availability factors to use for grass because the factors vary with the time of year that the manure will be spread on the grass. For manure applied to grass from the late fall to early spring prior to first cutting, the appropriate availability factor is 40%. This is because during this cold, wet period there is less potential for volatilization and in an established grass stand, uptake continues late into the fall and begins early in the spring. For manure applied during the summer, the potential for volatilization losses from manure applied to grass will be greater. Thus, if manure is applied on the surface of a grass field between later cuttings, and there is no rain for a week, the N availability factor is only 20%. However, if manure is applied immediately prior to a significant rainfall, the availability factor is 50%. If rain falls sometime within the first week the availability can be adjusted between these two extremes.

For this practice to be successful there are several important rules. The manure should be applied as soon after cutting as possible. It should be applied at a rate that matches the nitrogen requirement of the next cutting. Finally, you need to be careful that the rate or the spreading equipment doesn't physically damage the crop.

Douglas Beegle
Agronomy, Soils



MANAGING ALFALFA DURING AND FOLLOWING A DROUGHT

Alfalfa in some areas of Pennsylvania is experiencing water stress and the question of alfalfa management during this time is being raised. But before we discuss the management of water-stressed alfalfa, lets look at how alfalfa responds to drought conditions.

Alfalfa is commonly referred to as a drought tolerant plant. During the onset of drought conditions, alfalfa will stop using carbohydrates for stem and leaf production and store those carbohydrates in the roots. This provides high levels of root carbohydrates for long term survival if drought conditions persist and the leaves become photosynthetically inactive. However, alfalfa's ability to survive a drought does not mean that alfalfa will not show drought related symptoms. Water-stressed alfalfa will experience decreased stem elongation and in some cases mature more rapidly. Leaf production is less effected by water stress than stem elongation. This results in higher forage quality of water-stressed plants than their unstressed counterparts.

To Harvest or Not to Harvest?

The primary criterion influencing the decision to harvest drought-stressed alfalfa should be based on the cost of harvesting and the value of the forage. The alfalfa plants may look weak and severely stressed during a drought; however, harvesting at the stage of plant development when you would normally harvest is recommended as long as adequate alfalfa is present to justify the cost of harvesting. The plant, even though it may be very short, will already have stored more than enough root carbohydrates to insure survival if the drought persists or insure regrowth is sufficient rains remove the drought conditions.



EMERGENCY FORAGES IN DRY YEARS

Because of the drought conditions and the resulting less than anticipated forage growth, I'm sure you have been asked what alternatives farmers have for forage production once the drought breaks. Here are some suggestions and sources for more detailed information.

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FARMERS WHO GRAZE:

These farmers may not have been able to produce sufficient hay/silage to get through the winter. For them, an option is to plant some forage crops in August (hopefully it will be raining again by then) that can provide grazing this fall and allow hay/silage to be made from their traditional pasture land. Following are some options:

Forage Brassica (e.g. Rape or turnip):
Small Grains (e.g. wheat, barley, rye, or triticale) For additional information on growth characteristics, establishment, fertility, and grazing management of these crops refer to Agronomy Facts 33, "USE OF BRASSICA CROPS TO EXTEND THE GRAZING SEASON" and Agronomy Facts 41, "STRATEGIES FOR EXTENDING THE GRAZING SEASON".

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FARMERS WHO DON'T GRAZE:

Most of the crops that could be planted at this late time and produce some forage are better suited for harvesting as silage rather than hay. These crops are listed below along with sources for more detailed information.

Summer-Annual Grasses (e.g. Sorghum, Sudangrass, Sorghum-sudan hybrids, and Millet). After July 15 these crops are really only an option for Pennsylvania's more southern and warmer counties. For most of the State these crops will not mature before cool fall weather and frost stop their growth. In a situation where the drought damaged corn has been harvested in July then these crops may be the only option because of herbicides used on the corn and the greater potential for carryover due to the dry conditions. For more information refer to Agronomy Facts 23, "SUMMER-ANNUAL GRASSES FOR SUPPLEMENTAL OR EMERGENCY FORAGE"

Small Grains (Oats and Rye, use taller varieties). Small grains should be planted as soon as possible and harvested for silage in the milk to soft dough stage. Generally, the milk stage is less desirable than the early dough stage because it is less palatable and studies indicate that animal performance may be reduced. Moisture levels between 60 - 70% 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 some stems are hollow and filled with air. Minimizing the length of the chopped material will help minimize silage heating and maintain forage quality.

In a Penn State study conducted at the Landisville (Lancaster Co.) Research Center small grains yielded more than sorghum-sudan grass when both were seeded on August 5.

Yield and TDN of four crops seeded on August 5
Corn (harvest on 10/5) - 1.5 ton/a and 61.2% TDN
Sorghum-sudan hybrid (harvest on 10/5) - 1.6 ton/a and 61.2% TDN
Oat (harvest at soft dough) - 2.1 ton/a and 75.8% TDN
Rye (harvest at soft dough) - 2.1 ton/acre and 68.4% TDN

Marvin Hall,
Agronomy, Forages

Pest Management:

QUICK NOTES - HERBICIDE PREHARVEST AIDS FOR SMALL GRAINS

2,4-D and Roundup Ultra are about the only options available for preharvest application in small grains to control or suppress tall weeds such as bindweed, dogbane, ragweed, velvetleaf, thistle and others. 2,4-D (low volatile ester) is labeled for wheat, barley, and rye. Roundup Ultra is labeled for wheat only. There are no preharvest labels for oats. Refer to a current herbicide label for additional information and restrictions.



QUICK NOTES- TOUCHDOWN 5 LABELED FOR POST APPLICATION ON ROUNDUP READY SOYBEANS

Zeneca has recently received EPA registration for use of Touchdown 5 over-the-top of any variety of Roundup Ready soybeans only (not Roundup Ready corn hybrids). Touchdown 5 can be applied at 1.2 to 3.2 pt/A (common rate - 1.6 pt/A) from soybean emergence through full flower. Touchdown may be tank-mixed with other soybean herbicides to enhance weed control.



ROUNDUP VS. TOUCHDOWN: WHICH ONE IS BETTER?

Almost everyone involved in corn and soybean production is familiar with glyphosate, which is marketed as Roundup Ultra by Monsanto. However, the introduction of Touchdown, which contains sulfate, by Zeneca has created some confusion. Both products contain the same active ingredient, N-(phosphonomethyl)glycine. The difference between the two herbicides is that glyphosate is the isopropylamine salt of the parent acid, whereas sulfosate is the trimethylsulfonium salt of the acid.

Does the amine salt influence the effectiveness of the herbicide? Once the herbicide is inside the plant, the amine salt disassociates from the parent molecule so there is no difference in the two herbicides at the site of action (EPSP synthase). It is possible that the different salts influence herbicide absorption (how fast the herbicide gets inside the plant). Zeneca claims faster action with sulfosate, however, we have not seen any differences in activity of the two products in Iowa State University tests.

Touchdown is formulated at 5 lbs active ingredient/gallon of product whereas Roundup Ultra is a 4 lb/gal solution. Because of this, use rates will likely be lower on a product per acre basis. Another difference is in adjuvant selection. Touchdown allows the use of additional adjuvant at 0.5% v/v, but this is rarely needed. Both Touchdown and Roundup Ultra allow the use of ammonium sulfate (AMS), which is recommended for most applications.

Until 1999 the main difference was in labeled uses of Touchdown. Prior to this year, the primary use of Touchdown in Iowa (and Pennsylvania) was as a burndown herbicide in no-till fields, while only Roundup Ultra could be used postemergence on Roundup Ready designated soybeans and corn. A label is was recently granted by EPA for the 1999 growing season (see related article in this newsletter) that will allow Touchdown to be applied postemergence to Roundup Ready soybeans (NOT Roundup Ready corn.) More information about Touchdown and the label for Roundup Ready soybeans can be found on the Zeneca website.

In summary, the difference between glyphosate and sulfosate is that they are different amine salts of the same molecule. As with different amine salts of 2,4-D, we do not expect significant differences in performance of the two herbicides. Users should keep in mind the differences in surfactant needs, use rates, and labeled uses.

This article was taken from the Iowa State Univ. Weed Science Online website and was written by Dr. Bob Hartzler.



POSTEMERGENCE OPTIONS FOR CONTROLLING YELLOW NUTSEDGE IN CORN AND SOYBEANS

Below are some post options for nutsedge control in corn and soybeans. Remember that yellow nutsedge is not that competitive with corn or soybeans, and that light infestations may not affect corn or soybean yield.

Table 1. Postemergence herbicides for yellow nutsedge control in corn and soybeans.
Herbicide Crop Product/A Control Ratinga Comments
POST
Atrazine 4L/90DF + COC corn 1.5-2 qt 4L
or
1.7-2.2 lb 90DF 		7 Apply while nutsedge is 4-8 inches tall and before corn is 12 inches in height. Add 1 qt of crop oil concentrate/A to spray solution. If corn is under stress from prolonged cold, wet weather or other factors, this treatment may cause crop injury. Refer to current atrazine label for use restrictions and additional information. (Restricted-use pesticide and groundwater advisory)
Basagran 4S (bentazon)

or

Laddok S-12 5L (bentazon + atrazine) 		corn, soybeans




corn		 1.5-2 pt


or

2.3 pt		 8




8+		 Basagran application should be made when nutsedge is 6-8 inches tall and actively growing. Add 1 q/A of crop oil concentrate to spray solution. Apply in a minimum of 20 gal of water/A and at a minimum pressure of 40 psi. Split-applications are suggested for improved nutsedge control. Make second application 7-10 days after the first, if necessary.

Laddok application should be made to actively growing nutsedge but before corn is 12 inches in height. Add 2 pt/A of crop oil concentrate to spray solution. For best results, cultivate 7-14 days after application. (Restricted-use pesticide and groundwater advisory)
Classic (chlorimuron) soybeans 0.5-0.75 oz 8 Apply treatment when nutsedge is 2-4 inches tall and soybeans have at least one trifoliate leaf; both should be actively growing. Always include a proper adjuvant with this product. Use a minimum of 10 gal of water/A at a pressure of 25-40 psi. If the soil pH is less than 7.0 at Classic rates of 0.5 oz/A or greater, do not plant corn for at least 9 months after application. Classic must be applied 60 days before harvest.
Permit 75DF (halosulfuron) corn 1 -1 1/3 oz 9+ Permit can be applied over-the-top or with drop nozzles from spike through layby (last cultivation) of corn and when nutsedge is 4-12 inches tall and actively growing. A nonionic surfactant or crop oil concentrate must be added to the spray solution. Spray volumes of 10 or more gallons of water/A at a pressure which provides thorough and uniform weed coverage is optimal. Refer to label for any additional information.
Tough 3.75E (pyridate) corn 2 pt 7+ Apply 2 pt product/A when nutsedge is 6-8 inches high. Treatment will burn back top growth but regrowth may occur. Use a spray solution of 20-30 gal of water/A at 30-40 psi. Tank-mixing with atrazine enhances activity.
Roundup Ultra 4S (glyphosate) Roundup Ready corn and soybeans only;

burndown/spot treatment		 1-2 qt


1-3 qt or
1-2% solution 		8 Apply 1 qt/A (single application) in Roundup Ready corn before 30 inches tall (V8) and 1-2 qt/A (single or split application) in Roundup Ready soybeans before flowering. Apply when nutsedge is >6 inches tall but before nutsedge flowering. Lower spray volumes/A (10 gpa) provide better control. Roundup Ultra does not require the additional adjuvants in the spray tank. Roundup is a nonselective herbicide and will injure or kill any plant it comes into contact with unless it is a Roundup Ready crop.
a10=95-100%,9=85-95%,8=75-85%,7=65-75%,6=55-65%. Ratings based on optimal application timing.

Dwight Lingenfelter
Agronomy, Weed Science



WHITE HEADS IN WINTER WHEAT FIELDS

Winter wheat is in the early stages of maturity. This is typically when we start noticing white heads showing up in isolated spots or at random across the field. There are at least five possibilities that can produce these symptoms: take-all, fusarium root and crown rot, cephalosporium leaf stripe, scab or head blight, and stem sawflies.

A fungus causes Take-All. Affected plants are stunted and uneven in localized areas of the field. Affected plants have a reduced number of tillers, ripen early, may lodge in all directions and have white heads. Roots, crowns and stem bases develop a brittle, dry, brown-to-black rot. A black mycelia mat develops under the lower leaf sheaths. Losses are greatest in fields with a short rotation between wheat crops. The fungus overwinters in the soil and crop debris.

Fusarium root and crown rot is caused by the same fungus that causes scab or head blight. Root and crown rot develops when the fungus invades injured root and stem tissues in cool wet weather. The damage is most evident in warm to hot weather when the plant is under stress. Seedlings may die while older plants mature early producing fewer tillers and white heads with shriveled kernels. Scab, on the other hand, develops when the fungus infects the spikelets during flowering. One or more spikelets per head turn prematurely straw colored while glumes on healthy spikelets are green. A pink to orange mold often grows at the base of diseased spikelets. Infected spikelets normally produce shriveled rough kernels. The fungus overwinters in the soil and on seed plus cereal, grasses and corn residues.

Cephalosporium leaf stripe is associated with wet soils and on fields planted to frequently to wheat. Yellow then brown stripes develop on the leaf and often continue the length of the leaf. One to four stripes develop per leaf. Diseased plants are stunted and produce white, poorly filled heads with shriveled kernels. The fungus overwinters in crop residue and soil near the surface.

The stem sawfly can cause stunted growth, stem breakage and white heads. This pest seldom causes significant yield losses. The sawfly larva has a wrinkled body, a brown head and is nearly legless. Detection of a stem filled with a sawdust-like cutting indicates the presence of sawflies. The use of crop rotations and seed treatments is the main means for controlling the root and seedling diseases. Planting varieties with varying maturity can aid in the control of head blight or scab. There is no recommended control of the sawfly.

Elwood Hatley,
CCA Agronomy, Small Grains



INSECT ALERT

The following insects can be active during this time period. This does not mean they have been seen in the state, but it is the period of time when they can injure crops. Insects that have been reported are shown in bold type and specifics about their management are presented in individual articles. Pictures of each corn insect species, economic thresholds, and scouting guidelines can be seen on our webpage at: http://www.fra.cas.psu.edu/. Also, insect and insect injury images for all crops are being added to the new Agronomy Guide website. Other websites of interest include the University of Maryland's Pest Report in (http://pest.umd.edu/ipm/AgIPM/CropAndIPMReport/CropIPMReport.html). Information on insect trap data and other IPM information can be found under http://www.udel.edu/IPM/. This website contains black cutworm data from a network of 50+ pheromone traps operated by Terra Inc., Bridgeville, DE (Galen Dively). The data is for Delaware, but may provide an alert to future black cutworm injury in Pennsylvania. A website of the Maryland Department of Agriculture operated by Dick Bean has information from a network of blacklight and pheromone traps. You can access the data at ftp://ftp.mda.state.md.us/plantpro/blt/weekly/ or call 800-492-2106. Again, the information is not for Pennsylvania but can provide an alert to pending insect problems.

Corn
armyworm
black cutworm
European Corn Borer
sod webworm		 billbug
corn rootworm larvae
flea beetle
stalk borer
Soybeans
bean leaf beetle
potato leaf hopper		 green cloverworm
thrips
Alfalfa
alfalfa blotch leafminer
meadow spittlebug
potato leafhopper		 cutworm spp.
pea aphids
Small Grains
armyworm

Corn Rootworm larvae - All areas in the state have passed the 5% hatch period of corn rootworm. Egg hatch will continue over about a three week period in southern areas of the state, a four week period in central areas, and a five week period in northern areas and areas of high elevation. Remember from Table 3 that five percent hatch occurs between 380 (western corn rootworm) to 474 (northern corn rootworm) degree days (DD). Soil insecticides applied at planting will protect the roots for about six to eight weeks. Soil insecticides applied to fields planted during late April and early May are reaching the end of there effective period. Those applied to fields planted in mid- to late-May should still provide ample protection against CRW root feeding. If Furadan 4F is to be applied as a post-emergence application, it should be timed to between one week before or after the date of 5% hatch for your area. This year the dry conditions would favor an applying the material on the early side to allow the minimal rainfall to move the pesticide into the root zone while larvae are still small. With the minimal rainfall in most areas of the state Regent may have a reduced effectiveness because of its low water solubility. This product has performed well when moisture is available to activate the material, but tends to have reduced performance if a field experiences extended dry conditions during the early growing season.

European corn borer (first generation) - In most areas of the state, we should be approaching or have passed the midpoint in the first moth flight. The beginning of first generation injury should be evident in the warmer areas of the state and should begin soon in the central regions. Scouting for first generation injury should begin at about 648 DD and insecticide control implemented at about 734 DD. If a Bt-corn hybrid was used in the field, evaluation of its effectiveness on first generation can be determined during this time.

Economic Threshold Values

A simple single value economic thresholds is 75% of plants showing leaf feeding and live larvae are found. More dynamics economic thresholds can be calculated using the worksheet in the publication, "Field Crop IPM Training and Reference Manual", in Table 14 on page 28 or by logging into the Fund for Rural America Webpage (http://www.fra.cas.psu.edu/) and using the interactive economic threshold calculator.

Meadow spittlebug - This insect is for the most part a not pest. However, it is mistaken frequently for the potato leafhopper. Spittlebug adults are much large 1/4 to 3/8 inches long verse 1/8 inches for potato leafhoppers. Also, spittlebug adults are either a mixture of brown shapes or dark brown and orange. Potato leafhoppers are pale yellowish green. Nymphs of the spittlebug feed within a foamy mass that looks like someone spit on the plant. These spittle masses are found in the area where the leaf petiole attaches to the stem. The nymphs are yellow to green in color, but still much larger than a potato leafhopper.

Economic Threshold Values

One or more spittle masses per stem.

Potato leafhopper - PLH adults are beginning to show up in the state. So far, however, numbers are low with only a few fields above threshold. These adults most likely arrived in the state on the last storm front that originated out of the Gulf of Mexico. Since we have been in a weather pattern where most storms that are originating in the Gulf are moving north of Pennsylvania, we have not received an influx of the pest. If this weather pattern changes and we begin to get these storms, then PLH numbers will increase. The adults that have arrived will begin laying eggs and their offspring will require about 28 days to reach the late nymphal and adult stages when they do most of their feeding. Therefore, the second cutting will most likely escape heavy pressure from the pest. The new adults that have developed on the second cutting, however, will move to regrowth in third cutting fields. The incidence of PLH injury is typically a little higher in the third cutting. By the fourth cutting, PLH numbers are usually declining. Since PLH pressure is low in the state, it is unlikely that soybean field will be injured by the pest.

Economic Threshold Values

See the publication, "A Pest Management Program for Alfalfa in Pennsylvania", for specific economic thresholds.

Stalk Borer - All areas of the state have entered the period when stalk borer larvae will be moving into young corn seedlings from grasses and large stems broadleaf weeds along the margins of fields. It is during this period that you should be on the alert for the pest and that rescue insecticide applications should be applied. Use the economic thresholds to determine if treatment is needed.

Young larvae migrate from other hosts when the stem diameter becomes too small for them or their current host is killed by a post-emergence herbicide application. Typically, injury is confined to the first 10 rows along a field margin. In cases where orchardgrass has escaped an earlier herbicide application, larvae will move when the orchardgrass begins to die back. If the presence of small stalk borer larvae is known prior to the herbicide application, it can be advantage to apply an insecticide with the herbicide. Otherwise, it is best to watch the field for the beginnings of injury and treat if needed. Injury by this pest can be expressed in several ways. In small plant (>V5) the flag leaf may be dead and drying up. This indicates that a larva has bored into the stem and has cut-off the growing leaves. In larger plants, the larvae feed in the whorl and the in the stem. Whorl feeding results in ragged looking leaves with elongated areas eaten out.

Economic Threshold Values

Leaf stage   Percent Infested Plants at
Three Corn Prices
    $2/bu. $3/bu. $4/bu.
V1   10 7 5
V2   12 8 6
V3   15 10 7
V4   16 11 8
V5   17 12 9
V6   34 23 17
V7   100 100 100

Dennis Calvin, Entomology

Agents Corner:


ARMSTRONG/INDIANA/WESTMORELAND COUNTIES

Although rain has been sparse in most areas of the region, and non-existent in some, the crops are surviving. In general, early-planted corn (around May 1) curled a few times under drought stress, but is growing and looks somewhat healthy. Later planted corn (late May) seems to be stunted and not growing at all. Sweet corn stands planted since June 1 are downright ugly, except for those with irrigation capabilities. Oat stands, especially late seeded crops, are variable at best.

On the upside, this was the best spring in recent memory for making timely first cutting forage crops, especially dry hay. Many producers were mowing in early May. For the last two weeks, daytime temperatures hovered in the 80s and 90s, with respectable humidity levels for field curing the latest of first cutting hay. With that exception, grass hay fields and pastures are very stressed. Alfalfa regrowth looks favorable, but some rain would be a great help. Temperatures have cooled significantly this week, and some moisture may accompany the front.

Cereal leaf beetle was reported in oat fields in Westmoreland County (early June), while Potato Leaf Hoppers have been sighted in alfalfa throughout the region already. I was introduced to Jerusalem Artichoke (in field corn) for the first time this spring. It could be a contender for the APD Weed Contest!

Hope you all get some rain over the next few weeks.

Rob Stout
Armstrong County

CRAWFORD COUNTY

Temperatures for the first half of June have been well above normal to near record breaking for our region. Rainfall amounts, on the other hand, have been lower than normal for this time of year. However, what limited rains we have received have been timely and crops seem to be doing very well in general. In fact, I recently traveled to central Pennsylvania and was quite surprised that our corn (and soybean) crops appear to be a week or two ahead of theirs. Apparently, our limited rainfall was timely enough to account for the differences in crop development.

With the corn and soybean crops' rapid germination and emergence, many producers found themselves challenged with late preemergence and/or postemergence herbicide programs rather than their intended preemergence programs. This seems to be a difficult scenario to be confronted with for many of our producers. In corn, as long as the corn is less than eight inches tall, 2,4-D and/or dicamba (Banvel or Clarity) can typically take care of most broadleaf weed problems. For grasses, Accent and/or Beacon are generally the "weapons of choice" for postemergence grasses. Emerged yellow nutsedge generally results in the application of Permit in the tank mix. A reminder that most postemergence applications generally call for the addition of a NIS (nonionic surfactant) or crop oil is an important consideration that should not be overlooked. Many producers seem insistent on adding atrazine or something for residual soil activity, although it has been my experience that it is frequently uncalled for. In the case of soybeans, the fact that most preemergence programs must be applied before the soybeans emerge helps prevent producers from trying "late preemergence" applications of herbicides. Some preemergence programs with Canopy XL have shown impressive burndown capabilities, even on some difficult perennials. Postemergence herbicide programs in soybeans generally result in producers selecting a product for postemergence broadleaf control (many of which cause at least temporary visible injury to the crop) in combination with a product for postemergence grass control. The selection of this combination must be made carefully because of the potential for antagonism with some combinations. However, in cases where herbicide resistant crops have been planted, such as Roundup Ready or Liberty Link, postemergence weed control is simplified considerably.

Corn, especially the earlier planted corn, is quickly approaching "sidedressing height" and some producers are already setting about that task. In general, canopy closure in wide-row soybeans is still a ways off.

In the case of perennial forage crops, second cutting of intensively managed grasses, generally took place the second week of June in the region. Second crop for most other legume and mixed hay crops is progressing well with some scattered showers and cooler temperatures that arrived this week. Some producers had indicated a concern over weevil pressure in alfalfa, and the leaf hopper pressure is building with threshold levels occurring.

Finally, spring cereal grains (oats and barley) are generally well into heading and progressing nicely as well. As usual, there is some concern, especially on later planted oats, regarding the heat that we've had and the related potential for blasting. Our limited acreage of winter cereal grains (wheat and barley) seem to be coming along nicely also with only limited or typical amounts of disease pressure.

Joel Hunter, CCA
Crawford County

JEFFERSON/CLEARFIELD COUNTIES

The conditions here can be summed up as Hot, Dry and Slow Growing. I am receiving reports of 25 to 50% reductions in first cuttings of hay crops.

Oats are heading but based upon height of the fields I have seen there won't be much straw produced. Corn fields are up but they do not appear to have an even germination and growth pattern. Some areas of the counties have received sprinkles of rain while others haven't seen any.

Susan Alexander
Jefferson County

LEBANON COUNTY

Crops in Lebanon need moisture but the situation is not critical as of 6/14. Lebanon received 969 heat units (base 50 from March 1) a little less than 100 units shy of the ten year average, which puts us ahead a few days this year so far. The county had an ideal planting window and some took full advantage of the openings to make that all important timing criteria for high yields. I will briefly cover some of the various crops and present status.

Corn populations (now at v-7) suffered some stand loss and most fields I visited were at the 25,000 ppa mark. Uneven corn emergence has been common this year. Its is amazing given that some planters are in extreme need of maintenance especially in regard to double disk openers! Just looking at the doubles and skips in some fields is enough to make a person cringe. Corn missed major seed maggot injury and early season cutworms. Moth captures indicate a moderate population of corn borer and armyworm in Lebanon with last weeks 7 day trap count of 40 ECB moths. Sweet corn growers need to be on a 7 day spray schedule. Most post treatments of Furadan were applied at the ideal stage for the rootworm larvae. Aphids (underside of leaf and on stem) were found in a few fields and were just below threshold. Velvetleaf and giant foxtail escaped some pre treatments in corn and most producers applied a rescue treatment which worked despite dry weather concerns. I personally did see corn wilt especially where weeds were present but the foxtail was not wilted indicating to me growth and therefore crop protection products worked well.

Soybean stands (v-3) established were much lower than seed drop due to some crusting, low soil moisture and seed depth variation. In my opinion standard drills struggled compared to a planter for soybean stand establishment and insuring even emergence. As a result of soil conditions the weeds got the jump over the beans and producers were forced to spray earlier than usual.

Alfalfa has gotten off to a great start with aggressive regrowth and second cutting needs to be done ASAP. Yields were at the 3 ton dm/acre for first cutting. Early season weevils caught me off guard and some stands were lost according to Mark Goodson of Agway as some fields were completely killed by weevils. Apparently our ace in the hole, the parasitic wasps, did not help much this year. Most fields I have swept for hoppers were clean early and most second cutting fields that are on time should remain clean through harvest. Third cutting will be a different story, I have found many nymphs and adults that will if dry weather persists grow rapidly.

Small grains suffered from the drought in fall and the drought this spring. Septoria started and stopped followed by powdery mildew start and stop dictated by moisture and temperatures. The flag leaves I looked at appeared to have some mildew spores but no enough to impact yield. Barley is being combined and wheat is turning as I write. Most producers were late in harvest of the barley, so that in combination with low moisture conditions, may indicate poor test weight and yields. Of course no one really knows until the harvest is in the bin.

Finally, on light soil, pastures are drying up and supplemental feeding is advised to protect crowns. There needs to be some real education in this area, too many producers are overgrazing and not fertilizing enough to maintain adequate stands.

On another note, please plan to attend the Statewide Forage and Silage Exposition to be held in Lebanon County. Four different types of custom machines and both self propelled and pull behind choppers outfitted with the latest in roller mills will be demonstrated by area operators. Biotechnology plots will be viewed with Round Up Ready, IMI, and Liberty resistant corn hybrids planted and sprayed with the proper locally used products. Penn State specialists will be on hand and topics such as current silage research on quality and hybrid interactions, forage specie and stand management, storage and feeding strategies as well as pricing silage and forages out of the field will be covered by the specialists. In addition, 18 hybrids are planted to be viewed the day of the event. If you would like to sign up to come or if you represent a company and would like to have a booth at the event please call me at 270-4391 ASAP. This program is co sponsored by the Pennsylvania Master Corn Growers Association. See you there!

Del Voight
Lebanon County

LYCOMING COUNTY

The region is approx. 3.5 inches short of rainfall for this time of the year. Subsequently, crop conditions are now stressed and are showing reductions in yields and plant height. Corn in the county ranges from 3" to 36" with much of it showing signs of curling during hotter days. Corn planted earlier is much better off then that which was planted in mid-May. Population checks done have been generally good but dry knobs are thinner then the surrounding rows. Planter problems have been easier to identify this spring due to the weather stress on the plants. Weed control ranges from total failure to excellent, again depending on the soil moisture conditions. Currently, much of the side dressing is being done along with late post- treatments for weeds (bur cucumber, shattercane, etc)

1st cutting alfalfa yields were normal for most of the are but the second cutting is below normal. Weevil damage was light and leaf hoppers are not showing up in large numbers yet although they have been observed in isolated fields. Grass hay yields are off approx 25% of normal.

Small grains are headed or now heading with oats being considerably shorter then normal. Barley is starting to ripen with reports of 30% in the lower part of the region. Disease pressure is low with the dry conditions. Soybeans are looking good but soil crusting was causing a problem earlier in some fields. There appears to be a 10% + increase in soybean plantings this year. Weed control in beans is looking fair to poor but the majority of them are Roundup Ready so there is still plenty of opportunity to control the problem.

The bottom line: the potential is still there but we need a long soaking shower soon to make the difference in yields, especially second cutting hay.

Tom Murphy
Lycoming County

SCHUYLKILL COUNTY

Like most of my fellow agents have been reporting, it has been dry to the point that corn even at the V5 stage has been showing signs of stress. Oat fields have apparently also minded the dryness because while well headed the stalks are short and the stands appear thin. First cutting hay was good in both quality and quantity but regrowth has been slow. But after the showers of the past few days things are reviving and to quote the former corn specialist we are now only ten days away from a drought.

Marketing Hay at Harvest vs. Storage for Later Sale

With the grain crop price outlook being a little less than optimistic, hay may be the best money maker for this crop year. But do you sell now, off-the-field, or store the hay for the more promising prices of next winter? There is no easy pat answer but there are some considerations that need to be made and they are the same considerations that should be made when deciding whether or not to store grain.

Let's use an example of hay made June 1 at a harvest moisture of 18% and a value of $90 per ton. If sold off-the-field, the income is $90. If the decision is to store the crop until some time next winter and sell it at a higher price several factors affect the income value. First is moisture shrink. Let's assume the crop dries in the barn from the 18% harvest moisture down to 12% moisture. This would amount to a 6.82% shrink or a reduction in weight of 136 pounds per ton. In addition the extra handling of the crop into and out of storage would result in some physical loss. Let's be conservative and set that at 3% or 60 pounds per ton. So the ton of harvested hay that was harvested will come out of the barn weighing only 1804 pounds. You would now need almost $100 per ton to receive the same amount of income as the $90 would have provided at harvest time.

Also to be considered is the cost of money (interest or opportunity value) representing the value of the crop while in storage. If the crop is to be stored 8 months and the interest rate is 7 % on the $90 per ton harvest value, the cost of money during the storage period would amount to $4.80 per ton. Another consideration is the labor cost of putting the crop into storage and taking it back out again. Let's estimate that to be a total of $5 per ton.

Summarizing the costs;
harvest price $90.00
shrink cost 8.84
Interest 4.80
Labor 5.00
Total $108.64

To net the same amount of money after storage, the hay in this example with a $90 per ton value at harvest would need to sell for $108.64 per ton.

J. Allan Shoener
Schuylkill County

WAYNE COUNTY

Lack of rain continues to be our biggest production issue of the 1999 growing season. As we head into mid June, precipitation amounts across Northeastern PA are about 3.00 inches below normal for the season. Rainfall deficits in May alone were 1.00 to 2.00 inches. Here in Wayne County we've received enough precipitation to maintain fairly normal corn growth, however hay and pasture growth has suffered.

The above normal temperatures during the past two weeks have pushed corn growth into the V5 to V7 stage. A number of weed escapes have been observed, presumably due to lack of rain to activate preemergent herbicides. Producers are scrambling to re-spray fields and sidedress nitrogen before the corn gets ahead of them. Black cutworm has been observed in many fields throughout the region in the past few weeks. I've seen infestations as high as 5 plants/100 (corn = V2) which was high enough to warrant an insecticide application. Fortunately, black cutworm activity will soon be tapering off for the year. Crows have been another notable pest this season.

Many consecutive rain-free weeks allowed producers to finish first cutting in a very timely fashion. Yields were down significantly, but the quality of this early-harvested first cutting should make up for quantity. Regrowth on our grass hayfields and pastures has been slow to non-existent. Most producers are waiting for rain before topdressing these fields with nitrogen.

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 2 to the required values in Tables 3 and 4. Choose a location that is closest to your site when making a comparison.

Table 2. Cumulative Degree Days for Corn and Insects for the Period Ending June 13, 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 595 453 142 1385 796 673 512 420
Crawford Meadville 622 486 137 1466 847 719 550 453
Mercer Mercer 623 487 136 1484 857 728 558 459
Bradford Towanda 617 483 133 1462 832 704 535 438
Lycoming Montoursville 647 519 129 1565 894 760 582 479
Tioga Mansfield 589 451 138 1381 785 662 501 409
Susquehanna Montrose 552 411 141 1292 727 608 456 371
Butler Butler 647 517 130 1568 906 772 595 491
Indiana Indiana 642 512 129 1566 901 767 590 486
Lawrence Lawrence Jct 628 490 138 1467 849 722 553 455
Blair Martinsburg 623 491 131 1528 874 742 569 467
Centre State College 622 490 132 1507 961 731 558 458
Columbia Bloomsburg 652 526 127 1595 909 773 593 488
Clearfield Curwensville 620 486 133 1490 854 725 554 454
Dauphin Elizabethville 668 545 123 1657 946 807 622 513
Bedford Bedford 654 530 124 1633 938 799 617 510
Mifflin Belleville 651 526 125 1602 917 781 601 495
Northumberland Sunbury 671 547 124 1653 945 806 621 512
Lehigh Trexlertown 678 557 121 1697 965 822 635 523
Schuylkill Hegins 650 524 125 1601 912 776 595 490
Westmoreland Greensburg 642 512 129 1576 908 773 596 492
Somerset Somerset 581 441 141 1421 813 686 522 428
Washington Washington 670 546 124 1663 964 823 639 530
Franklin Chambersburg 690 573 117 1750 1006 859 666 552
York York 706 593 114 1810 1039 887 689 572
Lancaster Ephrata 675 555 120 1704 970 827 638 527
Berks Hamburg 684 564 120 1714 977 833 644 532
Corn degree-days based on a May 1 starting date. Insect degree-days based on a January 1 starting date.


Table 3. 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 4. 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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Website Address: http://fcn.agronomy.psu.edu/