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July 16, 1999 Vol. 99.8

IN THIS ISSUE:

Mark Your Calendar

Production

Pest Management

Agents Corner

Degree Day Accumulations

Production:

SMALL GRAINS FOR SUPPLEMENTAL FORAGE

Drought conditions across most of Pennsylvania have resulted in lower quantities of forage and grains for livestock producers. Many are facing the possibility of needing additional forage this fall and/or next spring.

One possible source is utilizing winter small grains for forage this fall (for grazing) or next spring (for grazing or silage). Winter grains can be grazed in the fall and early spring without greatly affecting grain yield if they are allowed to go into the winter with approximately two to three inches of growth and the cattle are removed in the spring prior to growth stage 6 or stem elongation.

When used for pasture winter small grains should be planted in mid-August to early September and can be utilized for grazing from October to late December and again in early spring. If the small grain is to be harvested for silage, grazing should be discontinued prior to Growth Stage 6 in the spring. When fall and spring silage production is desired, seeding a mixture of spring oat and a winter grain is suggested since it is difficult to harvest a winter grain for silage prior to Growth Stage 6. Spring oat can also be seeded in mid-August for fall grazing or silage production.

All winter grain species can be harvested for forage. Winter rye has traditionally been the major small grain used for forage. It has the most winter hardiness and can be planted the latest for both erosion control and forage. It does, however, drop in quality faster then the other small grains. Therefore, it must be harvested prior to head emergence (boot stage). Other small grains can be harvested later; however, most are harvested at about head emergence to allow earlier planting of corn or sorghum for silage. In most years' rye is ready in late April, barley in early May, wheat and triticale in early to mid-May. Seeding other winter grains with rye (rye-wheat, rye-triticale) has helped maintain quality when rye harvest is delayed past head emergence.

Spring oat and spring barley can also be used for forage. Seed early (mid- to late March). Mixtures of spring grains and peas are available and should also be seeded early. Harvest at head emergence (Growth Stage 10), which is in early June. Grain or forage crops can be seeded after harvest.

When planting small grains for forage, increase the seeding rate 30%. If grazing in the fall, apply 40 to 50 lbs. nitrogen per acre at planting to stimulate late summer and early fall growth. Follow the recommendations in the Agronomy Guide for phosphorus and potassium applications. Do not delay applying spring nitrogen. Apply the required amount at green-up in early spring. Early applied nitrogen can stimulate additional tillering which may contribute to dry matter production.

Elwood Hatley, CCA,
Agronomy, Small Grains

FALL FERTILIZATION OF FORAGE CROPS

The question of fall fertilization of forage crops is most often related to concerns about winter survival of perennial forages. While fall fertilization can have an impact on winter survival there are many other factors that influence winter survival, including the overall nutritional management of the crop, harvest practices throughout the year, weather conditions, and varieties just to name a few. Here I will focus only on the nutritional factors.

For new seedings the key to winter survival is to have a healthy, well-established plant going into the first winter. Having soil test levels at least in the optimum range for pH, phosphorus, and potassium before establishment is critical. While all of these fertility factors are important, it has been shown that good levels of phosphorus will promote vigorous root growth in the new seeding. A larger, more well established root system will be more resistant to heaving, which is a major cause of winter stand loss, especially in new seedings. A fall application of fertilizer to a new seeding cannot make up for the lack of good fertility at planting and resulting small root system.

Once a forage crop is established, the fertility program should focus on maintenance of good fertility levels in the soil for the life of the forage stand. The most important part of the maintenance program is regular soil testing to determine the need for lime, phosphorus, or potassium to replace the large amount of nutrients removed in the forage. On grasses nitrogen will also be an important part of the maintenance fertility program. For legumes and grasses, potassium seems to be the most critical nutrient for winter survival. Potassium, being a salt, lowers the freezing point of cells just like applying salt to a road lowers the temperature where the water on the road will freeze. Also, potassium influences the levels of soluble sugars in the cell sap. These sugars act as antifreeze in the plant cells enabling them to withstand lower temperatures without freezing

The timing of phosphorus and potassium applications for forages will depend on the situation. When the soil test levels are in the optimum range and the recommendations are low, the timing of fertilizer application is not critical. These low recommendations on an optimum testing soil are only to replace what the crop will remove so that the test level is still in the optimum range going into the following season. Fertilizer can be applied after one of the cuttings or in the fall. There will be no advantage to splitting the fertilizer application in this situation. Given a choice between applying the fertilizer during the season or in the fall, fall application may provide a very slight insurance effect, but this is not a major consideration.

Where high rates of fertilizer are recommended there may be an advantage to splitting the application some after first cutting and the balance in the fall. Many plants will take up potassium whether they need it or not. This is called luxury consumption. If all of the fertilizer is applied at one time, the next cutting may take up more than it needs leaving the crop short later on. By splitting the applications the efficiency of potassium use will be improved because there will be less luxury consumption. Also, as noted before, if the soil test levels are low enough to result in a large recommendation, particularly for potassium, applying some of the fertilizer in the fall before the plants are dormant may improve winter survival.

On forage grasses nitrogen is another consideration. Nitrogen should be applied to grasses in the spring and after each cutting, except the last cutting in the fall. The rate should be based on the expected yield of the following cutting. Applying nitrogen in the fall for use by the crop the following spring is not recommended. Another important consideration for nitrogen fertilization of grasses is the balance between nitrogen and potassium. Nitrogen applied in the fall on soils with low potassium levels can increase winter kill of grasses over where no fertilizer is applied. Thus, soil testing and applying a balanced fertility program is important.

There are no special considerations for nutrient sources used for fall fertilization of forages. All of the standard fertilizer materials are acceptable. Manure is also a source of nutrients. The phosphorus and potassium in manure can be considered equivalent to fertilizer phosphorus and potassium in their effect for building soil fertility. The availability of nitrogen will range from 20 to 50% depending on how soon after application it is soaked into the soil by rain fall. The sooner it gets rain the better. Manure is not generally recommended for legumes because the nitrogen in the manure is wasted and there is the potential for some adverse effects from manure application to legumes. If manure must be applied to a legume, fall is probably the best time to apply it to minimize the potential negative effects.

While having good fertility levels for a forage crop in the fall is critical for optimum production, fall fertilization is only one part of the management system to achieve this. Optimum soil test levels should be established prior to seeding and a maintenance fertilization program based on regular soil testing are the foundation of good nutrient management of forages.

Douglas Beegle, Agronomy
Soils

POLLINATION AND THE CORN CROP

The prevailing drought conditions throughout much of the state may adversely affect the pollination of the 1999 corn crop. Under normal conditions, tassel emergence begins in some fields about July 15 and continues in others until about August 15. Ideally, pollination should occur in most areas by August 1 since about 60 days are required to mature the crop following pollination.

Drought stress will also affect ear development and pollination. In most plants there is an internal competition for vegetative development, tassel development, and ear shoot development. With severe drought stress prior to tasseling, ear shoot development can be delayed. This can result in barrenness or delayed silk emergence. If silk emergence is delayed significantly following pollen shed by the tassels, then incomplete pollination can occur.

Silk elongation normally begins 7 to 10 days prior to silk emergence from the husk. Complete silk emergence from an ear generally occurs within two to seven days. Silks from the basal portion of the ear typically emerge first, while the tip silks generally emerge last. Pollen shed normally coincides with silk emergence and lasts for up to 7 days on an individual tassel. Because of plant variability in typical fields, pollen is sometimes available for up to 14 days.

Pollination can also be limited if emerging silks are clipped by rootworm beetles. Generally at least a half-inch of emerged silk is required for successful fertilization to occur. The recent high temperatures have caused high corn rootworm beetle populations in some fields. In some situations this year, control of the rootworm beetles may be necessary to prevent serious silk clipping. The threshold for corn rootworm beetles is 5 per plant before an insecticide should be considered.

Pollination can be assessed by gently pulling the husks off of an ear once the silks have turned brown and then gently shaking the ear. Those silks that remain attached to the ear were not pollinated. Often these will be the late emerging silks from the ear tip but they can be scattered throughout the ear.

Once the pollination process is complete, a rough yield estimate can be made by determining the average number of kernels per ear and multiplying it by the plant population. Multiply the number of rows by the number of kernels per row to get the number of kernels per ear. Then multiply this number by the plant population to get the kernels/acre. Divide the kernels/acre by 90,000 to get the yield estimate in bushels/acre.
Example: 16 rows x 20 kernels/row x 23000 plants/acre = 7.36 million kernels/acre 7.4 million/90,000 = 82 bushels/acre

Yield estimates can be useful to make marketing decisions. Row numbers and especially kernels per row will likely be reduced in many fields because of the drought stress that occurred while these yield components were being determined.

Greg Roth, Agronomy
Corn and Sorghum Management

Pest Management:

NATIVE VS. NON-NATIVE PLANTS

In the last Field Crop News, I introduced you to the 'Invasive Species Executive Order that will likely impact plant management programs over the next several years. One area of controversy deals with categorizing plant species based on their origin. Non-indigenous, nonnative, exotic, foreign, introduced, alien, invasive, noxious, are all terms used to describe weedy pests. All of these definitions incorporate a basic concept: invasive plants are plants that have been introduced into an environment in which they did not evolve and thus usually have no natural enemies to limit their reproduction and spread. Whether plants are transported across an ocean to a new country or across a mountain range into a new valley or from an infested farm to a non-infested farm, the result is often the same - they can become a problem, especially when humans intervene. About 8000 species or 3% of all known plants are considered to be invasive in agriculture. However, of these, only about 200 to 250 species (less than 0.1% of the total) are recognized as major problems in world agriculture. Table 1 lists some common weeds and their suspected origin in the broadest sense.

All species are constantly shifting in both their distribution and abundance. The controversy over "native vs. non-native" or "good vs. evil" is not easily resolved. In the most simple definition, native to North America is defined as being present prior to settlement by Europeans. However, by this definition we would include corn and squash along with a number of agricultural weeds associated with native American agriculture. Numerous species were introduced as crops by indigenous peoples prior to European colonization (remember the Bering Strait theory). Also, native to one region (i.e. upper Midwest, central Mexico, etc.) doesn't make it native to all North America. Some purists would prefer a definition for indigenous that includes criteria such as fossil evidence, historical evidence, genetic diversity, reproductive patterns, relationships with plant eating insects and mammals, and at the very least a cutoff date sometime between 3000 and 10,000 years ago after the most recent glaciation, but prior to extensive agriculture in North America.

Table 1. Some common weeds and their suspected origin.
Cropland weeds Suspected Origin Pasture/
range-land weeds		 Suspected Origin Forestry/
rights of way/
wetland weeds		 Suspected Origin
Burcucumber N. America Bedstraw, smooth Europe/Asia Bittersweet, oriental Asia
Cheatgrass Mediterranean Bindweed, hedge Europe/Asia Hogged, giant eastern Europe
Chickweed, common N. America Burdock, common Europe Honeysuckle, Japanese Asia
Dogbane, hemp N. America Dandelion Europe/Asia Ivy, English Europe/Asia
Foxtail, Giant China Dock, curly Europe/Asia Knotweed, Japanese Asia
Goatgrass, jointed Asia Dogbane, hemp N. America Kudzu Asia
Johnsongrass Mediterranean Four-o-clock, wild Tropical America Loosestrife, purple Europe
Lambsquaters, common Europe/Asia/
N. America? 		Ironweed, tall N. America Maple, Norway Europe
Morningglory, Tall Tropical America Knapweed, spotted Europe Mile-a-minute Asia
Nightshade, Eastern Black Europe? Milkweed, common N. America Mustard, garlic Europe
Nutsedge, Yellow Europe/Asia Mullein, common Europe/Asia Olive, autumn Asia
Oats, wild Europe Pokeweed, common N. America Olive, Russian Europe/Asia
Pigweed, smooth N. America Quackgrass Europe Reed, common Europe/Asia
Ragweed, common N. America Rose, multiflora Asia Asia Asia
Shattercane Africa Snakeroot, white N. America Watermilfoil, Eurasian Europe/Asia
Shepherdspurse Europe Spurge, leafy Europe/Asia    
Smartweed, Penn. N. America Thistle, Canada Europe/Asia    
Velvetleaf India Thistle, musk Europe/Asia    
Wirestem muhly N. America St. Johnswort Europe/Asia    

So, are crownvetch, tall fescue, birdsfoot trefoil, sweet clover, and reed canary grass, to name a few, noxious weeds because they can be invasive in some environments/situations and are non-native to North America. Or….are these useful plants that serve some benefit such as valuable forage, protection from soil erosion, or habitat for wildlife in other environments/situations. This is the type of debate we currently face as we decide what goals we seek as land managers and what is appropriate - Produce high yielding crops, reduce soil erosion, produce habitat for wildlife, maintain genetic or species diversity, create historical representations of pre-European habitat. What are the goals?

Bill Curran, Agronomy,
Weed Control

CONSIDER MANAGING THOSE PERENNIALS NOW

Late August or early September is an excellent time to attempt some control of perennial weeds including hemp dogbane, horsenettle, milkweed, Canada thistle, quackgrass, bindweed, etc. Fall treatments are usually longer lasting and more successful than attempting to continually suppress these weeds in corn or soybeans. However, in order to use the benefits of mother nature, targeted fields must be fallow or recently harvested to allow regrowth of the perennial weeds prior to herbicide application. Winter wheat or barley, spring oats, sweet corn or some other vegetable crops can allow for this late summer application. Apply Roundup Ultra at 1 to 3 quarts per acre to perennial weeds that appear green and healthy (insect damaged or disease infested plants are not as susceptible as healthy plants). Include 1 to 2 pints of 2,4-D or Banvel/Clarity in the tank-mix to broaden the spectrum of control. Some tillage (moldboard or chisel plow) a minimum of two weeks after the herbicide application can improve control.

WEED CONTROL OPTIONS FOR LATE SUMMER ALFALFA ESTABLISHMENT

August can be an excellent time to establish alfalfa. Seeding the crop in late summer can avoid some of the weed problems that typically occur with spring seedings, especially if the field has been in corn or some other summer annual crop during the past two to three years. Summer annual weeds like lambsquarters and pigweed are usually not a threat to August seedings. However, if a winter cereal grain was the previous crop, be sure you recognize the winter annual weeds that could be a problem the year of establishment. Study the crop and weed history of the field to identify the best weed management tactics.

Some options for late summer seedings:

  1. Try to reduce perennial weed problems prior to seeding. Roundup Ultra is an effective herbicide for many perennial weeds and may be applied prior to seeding forages. Avoid the use of 2,4-D and especially Banvel/Clarity prior to seeding alfalfa or other forage legumes.

  2. Controlling annual weeds after alfalfa and weed emergence can be successful. 2,4-DB or Buctril are effective on a number of winter annual mustards. However, both tend to be weak on wild radish as well as chickweed, henbit, and red deadnettle. Poast Plus/Poast or Select can control several annual grasses in new alfalfa seedings. Perennials such as quackgrass are difficult to remove from alfalfa with Poast Plus but Select may provide adequate suppression. These "POST" products are most effective when applied prior to frost when air temperatures are still relatively mild.

  3. Pursuit is labeled on seedling and established alfalfa during establishment year. Pursuit should be applied to small actively growing weeds when the alfalfa has at least 2 trifoliates. Pursuit is effective on many broadleaf weeds including chickweed and a number of winter annual mustards. Be sure to apply Pursuit when weeds are small and include the appropriate adjuvants (nonionic surfactant or crop oil concentrate plus UAN).

  4. Both Gramoxone and Sinbar allow dormant season applications during the seeding year of alfalfa. These programs are generally targeting winter annual broadleaves such as chickweed. However, both herbicides can injure young alfalfa, especially if not completely dormant or when other plant stress occur (i.e. cold weather, disease, etc.).

  5. Other pre options include Balan and Eptam, however each must be incorporated prior to planting. These herbicides provide good control of many summer annual weeds so they generally have limited use in fall alfalfa seedings. They are effective on downy brome and annual bluegrass. Do not use Eptam within 12 months of atrazine application.

Corn Herbicide Rotation Restrictions

With the drought in much of the commonwealth, many producers may consider trying to establish a late summer crop for additional forage or feed. Herbicide recrop restrictions are based on susceptibility of potential rotation crops to herbicide residues or are based on limits set by EPA for potential residue in feed or food crops. In drought conditions, several herbicides have the potential to persist longer in the soil and injure susceptible follow crops. Pay particular attention to atrazine, simazine (which can cause problems even in a more "normal" year), and the herbicides with 3 to 5 month crop rotation intervals for alfalfa, clover, or small grains. Refer to the current Penn State Agronomy Guide, Field Crop Weed Control Guide or the herbicide label for rotational crop restrictions. Also, consult the label if two or more of these materials are applied during the same season.

CORN HERBICIDE GRAZING, FORAGING AND GRAIN HARVEST RESTRICTIONS

If early harvest of corn is necessary because of drought conditions, a number of corn herbicides restrict the length of time necessary for safe harvest. The following products restrict grazing and/or foraging (silage) following their use in corn. If a corn herbicide product is not listed in the following table, no grazing/feeding restrictions were listed on the product label. For additional information, contact the product manufacturer.

Table 2. Corn herbicide grazing, foraging and grain harvest restrictions.
Corn herbicide Graze Silage/grain
  (Days after treatment)
Accent 30 30
Aim 0 0
Atrazine 21 21
Banvel or
Marksman		 after milk stage after milk stage
Basagran 12 12
Basis 30 30
Basis Gold 30 30
Beacon/
NorthStar 		30 45/60
Broadstrike + Dual 85 85
Buctril 30 30
Celebrity after milk stage after milk stage
Exceed 30 40/60
Gramoxone Extra
(post directed)		 do not graze do not feed
Hornet 85 85
Laddok 21 21
Liberty 70 60/70
Lightning 45 45
Pinnacle 30 30
Pursuit 45 45
Poast Plus/Poast 60 45/60
Python no 85
Resource 28 28
Roundup
(spot treatment) 		14 14
Roundup Ultra1 501 50/71
Scorpion III 85 85
Sencor 60 60
Shotgun do not graze -
Stinger 40 40
2,4-D 7 7
1 Do not graze, ensile, or feed corn if sequential applications of Roundup were applied to Roundup Ready corn hybrids

Bill Curran and Dwight Lingenfelter
Agronomy Weed Science

Agents Corner:

LYCOMING COUNTY

The region continues to be very dry with a rain deficit of over 3.50 inches since the middle of April. Most of the crops in the area are showing some type of damage, yield reduction, or stress. There were showers through the area 10 days ago that brought 2 to 3 inches of rain but it was consumed by the crops since that time with the hot, dry conditions.

Corn is tasseling now in most fields with some appearing as early as the 1st of July, which hasn't happened since the 70's. Most all fields observed are showing some type of moisture stress with the sandy soils being the worst hit. Most fields are also showing a very uneven corn height, which is attributed to the dry conditions earlier in the season. Silking in those areas will be uneven and is assumed to be a factor in yields this fall. European corn borer damage is not a large problem in most fields but corn rootworm beetles are now emerging in larger numbers then have been observed in the past. Some fields have counts as high as 20 per plant, which will have an impact on cropping decisions next year.

Alfalfa quality with the reduced rainfall has been running good to excellent but the quantity is off by 30 to 50% (2nd and 3rd cutting) depending upon the location in the region. Leafhopper damage is still lighter then normal. Mixed hay is all harvested and regrowth is very limited.

Soybeans are looking fair to excellent depending on the time they were planted with height ranging from 10 inches to 3 feet. They seem to be tolerating the drought better then most crops. Weed control is mostly excellent since most producers are using the Roundup Ready seed. We are just starting to see mites in some fields, especially along the edges of grassy areas. So far, we haven't seen or had reports of white mold in soybeans. I expect we will have some pretty decent bean yields this fall.

Small grains have been variable with wheat and barley showing strong harvest yields but oats expected to come in lower than normal. Oat straw will be at the absolute minimal this year.

The bottom line is we need rain, we need it now, and we need lots of it!

Tom Murphy
Lycoming County

WAYNE COUNTY

Like many areas of the state, Wayne County has had limited rainfall for the entire growing season. However sporadic, yet timely, rains throughout the summer have kept most crops green and growing - never enough to make us comfortable but enough to keep things growing. Our corn crop looks surprisingly good with most producers expecting better than average tonnage this Fall. Most corn fields have only been visibly stressed (rolled leaves) one or two days thus far. The only fields that do not look good are those where adequate weed control was not achieved. Unless we have a dramatic change in our weather pattern, soil moisture will continue to be our biggest concern, especially as we head into tasseling and grain fill. Hopefully our luck will hold out and we will end up with a respectable corn crop this Fall.

Our grass hay and pasture fields have been hardest hit this summer. First cutting yields were down significantly and second cutting is almost non-existent. Producers that decided to make a second cutting report yields that are 20% to 30% of normal harvest. Graziers have been supplementing pasture with stored forages for several weeks now. Interestingly, some producers spent the month of June mowing hay in old meadows that are rarely harvested. The quality of this late-made first cutting will be poor; however the extra bales may serve a critical need this winter.

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 July 11, 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 1132 930 202 2204 1391 1212 969 823
Crawford Meadville 1186 996 189 2311 1468 1284 1032 881
Mercer Mercer 1183 995 188 2326 1474 1290 1037 884
Bradford Towanda 1202 1002 199 2328 1474 1291 1038 887
Lycoming Montoursville 1256 1070 186 2456 1560 1371 1109 950
Tioga Mansfield 1140 931 209 2214 1394 1215 971 825
Susquehanna Montrose 1070 844 226 2093 1304 1130 895 757
Butler Butler 1233 1056 177 2436 1549 1360 1099 940
Indiana Indiana 1225 1045 180 2431 1542 1352 1092 933
Lawrence Lawrence Jct 1197 1009 189 2319 1476 1293 1040 889
Blair Martinsburg 1188 999 190 2376 1498 1310 1053 898
Centre State College 1195 1003 191 2362 1492 1305 1050 895
Columbia Bloomsburg 1267 1083 184 2491 1581 1390 1126 965
Clearfield Curwensville 1186 995 192 2339 1478 1293 1039 885
Dauphin Elizabethville 1292 1116 176 2563 1628 1433 1164 999
Bedford Bedford 1251 1077 174 2512 1592 1397 1132 969
Mifflin Belleville 1255 1076 179 2487 1578 1386 1122 961
Northumberland Sunbury 1301 1124 177 2565 1632 1437 1168 1004
Lehigh Trexlertown 1318 1142 176 2619 1663 1464 1193 1026
Schuylkill Hegins 1259 1076 183 2492 1579 1387 1123 962
Westmoreland Greensburg 1219 1040 179 2436 1544 1353 1092 933
Somerset Somerset 1092 881 211 2215 1382 1200 953 806
Washington Washington 1272 1107 165 2547 1624 1427 1159 995
Franklin Chambersburg 1326 1163 163 2668 1700 1496 1219 1050
York York 1363 1203 159 2748 1753 1545 1262 1090
Lancaster Ephrata 1308 1134 174 2618 1660 1461 1188 1022
Berks Hamburg 1329 1156 173 2641 1679 1479 1206 1038
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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