in-crop-weather State Indiana Crop Weather Week Ending Date July 7, 2002 Issue IN-CW2702 Agricultural Summary Hot, dry weather with day time temperatures reaching into the 90 degree range placed stress on major crops and livestock during the week, according to the Indiana Agricultural Statistics Service. In many fields, corn leaves were rolling and soybean plants were showing effects from the heat and lack of rain. There was virtually no precipitation around the state, except for isolated showers in a few northwestern areas. Winter wheat harvest was in full swing in the central region and gaining momentum in the northern areas of the state. Cutting and baling hay along with spraying soybean fields for weed control made good progress during the week. Pastures are drying out rapidly. Field Crops Report There were 6.9 days suitable for fieldwork. Corn condition declined and is rated 48 percent good to excellent compared with 62 percent last week and 78 percent last year at this time. Planting of double crop soybeans was winding up in most of the southern regions last week. Soybean condition is rated 51 percent good to excellent compared with 61 percent last week and 66 percent a year earlier. Six percent of the soybean acreage is blooming compared with 25 percent last year and 23 percent for the 5-year average. Other activities during the week included mowing roads and pastures, cleaning up and repairing equipment, scouting fields, baling straw, cultivating row crops, moving grain to market, cleaning grain bins and taking care of livestock. Winter wheat condition is rated 50 percent good to excellent, unchanged from a week earlier, but below the 69 percent a year ago at this time. Wheat harvest is 65 percent complete compared with 63 percent last year and 61 percent for the 5-year average. By area, 15 percent of the wheat acreage is harvested in the north, 76 percent in the central regions and 96 percent in the south. Livestock, Pasture and Range Report Pasture condition is rated 3 percent excellent, 44 percent good, 38 percent fair, 12 percent poor and 3 percent very poor. Second cutting of alfalfa hay is 25 percent complete compared with 37 percent last year and 38 percent for the average. Transplanting of tobacco is virtually complete. Livestock were under stress due to the hot temperatures and flies were also a problem. Crop Progress Table -------------------------------------------------------- : This : Last : Last : 5-Year Crop : Week : Week : Year : Avg -------------------------------------------------------- Percent Corn Silked 2 0 20 13 Soybeans Blooming 6 3 25 23 Winter Wheat Harvested 65 42 63 61 Alfalfa Second Cutting 25 NA 37 38 Crop Condition Table -------------------------------------------------------- : Very : : : : Excel- Crop : Poor : Poor : Fair : Good : lent -------------------------------------------------------- Percent Corn 4 12 36 42 6 Soybean 2 12 35 46 5 Pasture 3 12 38 44 3 Winter Wheat 2002 2 14 34 43 7 Soil Moisture & Days Suitable For Fieldwork Table ------------------------------------------------------- : This : Last : Last : Week : Week : Year ------------------------------------------------------- Percent Topsoil Very Short 20 4 4 Short 42 21 12 Adequate 36 64 72 Surplus 2 11 12 Subsoil Very Short 7 1 6 Short 34 11 15 Adequate 55 74 71 Surplus 4 14 8 Days Suitable 6.9 5.5 4.5 Contact information --Ralph W. Gann, State Statistician --Bud Bever, Agricultural Statistician E-Mail Address: nass-in@nass.usda.gov http://www.nass.usda.gov/in/index.htm Other Agricultural Comments And News Soybean Aphid in Indiana * Aphids are moving from winter to summer host * Brief information on biology and damage given * Checklist of considerations before treating * Many insecticides, if applied properly, should control soybean aphid Soybean aphid, Aphis glycines Matsumura, was found on June 18 at the Agronomy Research Center, Tippecanoe County, on V3 soybean plants. This indicates that soybean aphids are now moving from their winter host, buckthorn, onto their summer one, soybean. This is our first observation, not an alert of an economic infestation. States in the northern Corn Belt observed this movement about one week earlier than we did. Groups attending Diagnostic Training Center sessions at the Agronomy Research Center looked for aphids as part of their training activity, but only ONE was found among such critters as thrips, spider mites, and whiteflies. Soybean aphid has a very complicated lifecycle. Simply put, female aphids feed-on and reproduce in the summer on soybean. Females give birth to female off-spring, so aphid numbers can increase quickly on soybean (it is estimated that populations can double every 2-1/2 days). In the fall, as temperatures drop and days grow shorter, a generation of winged females and males are produced. Both migrate from soybean to their over-wintering host plant Rhamnus, a shrubby tree also known as buckthorn. Eggs are laid on buckthorn, which over-winter and hatch in the spring. Aphids emerging in the spring are females. After several generations on the overwintering host, winged spring migrants fly to soybean to establish new colonies. The soybean aphid feeds by using a needle-like, sucking mouthpart to remove plant sap. Plant damage occurs from large numbers of aphids removing a significant amount of water and nutrients as they feed on leaves and stems. Some isolated fields in east central Indiana, in 2001 had plants that were covered with aphids, and leaves that were curled and wilted. Leaves on the bottom-third of plants were covered with shed aphid skins (resembling white powder) and aphid secreted honeydew, both of which are signs of aphid presence. Gray sooty mold growing on the honeydew, also covered these leaves. Plants covered with aphids were often stunted when compared to plants from other parts of the field. In some cases, heavily infested plants showed dramatic leaf yellowing. This yellowing may have been associated with potassium (K) deficiency, because symptoms can be more pronounced in fields where both high numbers of aphids and deficient levels of K are found. It is too early to speculate on how severe the infestations will be in the Midwest, much less Indiana, for this season. Considerable time and effort has been and will be devoted to this pest throughout the Corn Belt because of its potential economic impact on soybeans. Indiana has had minimal crop damage due to this aphid since its discovery in 2000. Therefore, our expertise in this area relies heavily on what we read and hear from colleagues in neighboring states. Many pest managers are asking about thresholds for this insect in case outbreaks occur. Christina DiFonzo, Michigan State University Entomologist, put together a treatment decision "checklist" this past winter. Her checklist follows: "Aphid distribution: Aphids on leaves and stems. When aphids begin to move from the undersides of leaves onto stems, the population is large and increasing. Aphids on stems generally are easy to see without a hand lens. Aphid number: Leaflet rating of at least 3.0. The leaflet rating is fairly quick and easy to do, and will allow you to assess aphid numbers after treatment. A rating of a 3.0 is a minimum of 25 aphids on every leaflet of the plant. Plant appearance: Honeydew (sticky substance) on plants. Honeydew is a sugary substance secreted by aphids as they feed. It is mainly an annoyance, although it promotes the growth of gray sooty mold on leaf surfaces. Honeydew is a sign aphid numbers are large. Aphid appearance: Healthy. Aphid-infesting fungi already exist in your fields, in the soil and on plant surfaces. These fungi specifically attack and infect aphids and can crash the aphid population in a field in a matter of days. Infected aphids are pinkish, white, or tan, and fuzzy from the growth of fungi out of their bodies. When weather conditions are favorable, the fungi can infest and control aphids quickly. Once a fungal infection starts, an insecticide spray may not be needed. Weather conditions: Warm and dry. Aphid pathogenic fungi reduce aphid numbers best in warm, humid weather. Under dry conditions, these fungi cannot infect aphids. When thinking about aphids and weather, think about the same conditions favorable for spider mite infestation in soybean. Timing: July. June is likely too early to assess aphid populations and make a spray decision. August is probably too late to get the most yield advantage from treatment. Plant stage: Flowering and early pod development. Flowering and early pod fill seem to be critical times for aphid control. Large numbers of aphid feeding on the plant may cause flowers and pods to abort. Also, there is Minnesota data showing that node number was reduced by large numbers of aphids. Spraying too late in the season, once pods are formed, is probably too late to get the most yield advantage from treatment." As well, predatory insects, especially lady beetle adults and larvae, lacewing larvae, and syrphid fly larvae, have been very abundant in infested fields and should provide some control, if present. Parasitic wasps, which lay eggs directly into aphids, have been less abundant, but still present. In addition to the above mentioned pathogenic fungi, these biocontrol agents have the potential to dramatically reduce aphid numbers in Indiana to below economic levels. Efficacy trials conducted by Michigan State and Minnesota demonstrated that many products control aphids in soybean. Complete coverage on the foliage, as with spider mites, seems to be the key. Last year, on-farm trials conducted in Michigan yielded from 2 to 24 bushels better than the untreated. Yield benefits decreased the later applications were applied in the season. Further information with many color pictures can be found in extension publication E-217, Soybean Aphid (new May 2001). A hard copy of this publication can be obtained by calling 1888-EXT-INFO or an electronic copy viewed at . John Obermeyer, Rich Edwards, and Larry Bledsoe, Department of Entomology, Purdue University. Weather Information Table Week Ending Sunday July 7, 2002 --------------------------------------------------------------- | Past Week Weather Summary Data |--------------------------------- Station | Air | | Avg | Temperature | Precip. |4 in. |---------------|-----------|Soil |Hi |Lo |Avg|DFN|Total |Days|Temp ------------------------------------------------------------- Northwest (1) | Chalmers_5W |98 61 80 +7 0.00 0 Valparaiso_AP_I |95 61 79 +7 0.83 1 Wanatah |96 59 79 +8 0.50 1 85 Wheatfield |94 59 79 +7 0.00 0 Winamac |95 60 79 +7 0.00 0 85 North Central(2)| Plymouth |94 60 79 +6 0.00 0 South_Bend |94 61 79 +7 0.00 0 Young_America |93 60 78 +6 0.00 0 Northeast (3) | Columbia_City |92 57 76 +5 0.00 0 81 Fort_Wayne |94 59 78 +6 0.00 0 West Central (4)| Greencastle |92 58 76 +2 0.00 0 Perrysville |94 63 79 +5 0.00 0 81 Spencer_Ag |93 62 78 +5 0.00 0 Terre_Haute_AFB |95 60 79 +5 0.00 0 W_Lafayette_6NW |94 61 79 +7 0.00 0 86 Central (5) | Eagle_Creek_AP |93 63 80 +6 0.00 0 Greenfield |93 60 79 +5 0.00 0 Indianapolis_AP |93 66 80 +6 0.00 0 Indianapolis_SE |92 61 78 +4 0.00 0 Tipton_Ag |93 58 78 +6 0.00 0 82 East Central (6)| Farmland |94 55 78 +6 0.00 0 80 New_Castle |90 56 75 +4 0.00 0 Southwest (7) | Evansville |96 63 82 +4 0.00 0 Freelandville |95 66 82 +7 0.00 0 Shoals |95 61 80 +5 0.00 0 Stendal |95 64 81 +5 0.00 0 Vincennes_5NE |96 64 81 +6 0.00 0 81 South Central(8)| Leavenworth |94 63 80 +6 0.00 0 Oolitic |93 63 79 +6 0.00 0 84 Tell_City |97 65 83 +7 0.00 0 Southeast (9) | Brookville |98 59 80 +8 0.00 0 Milan_5NE |91 57 76 +3 0.00 0 Scottsburg |95 55 78 +3 0.00 0 ------------------------------------------------------------- ------------------------------------------------------------- | Accumulation | April 1, 2002 thru Station | July 7, 2002 | Precipitation |GDD Base 50oF | | | | | |Total | DFN |Days|Total| DFN ------------------------------------------------------------- Northwest (1) | Chalmers_5W |10.77 -1.34 42 1315 +15 Valparaiso_AP_I |12.29 -0.72 37 1295 +154 Wanatah |11.95 -0.43 40 1226 +142 Wheatfield |11.06 -1.19 33 1258 +141 Winamac |11.27 -1.04 40 1242 +65 North Central(2)| Plymouth |12.81 -0.03 41 1180 -48 South_Bend |10.21 -1.85 39 1238 +114 Young_America |12.52 +0.70 37 1337 +143 Northeast (3) | Columbia_City |11.09 -1.06 39 1154 +88 Fort_Wayne |13.17 +1.95 36 1298 +115 West Central (4)| Greencastle |18.71 +5.39 39 1283 -99 Perrysville |17.25 +4.11 40 1382 +99 Spencer_Ag |19.67 +5.78 43 1365 +85 Terre_Haute_AFB |25.23 +12.24 42 1526 +150 W_Lafayette_6NW |16.87 +4.72 46 1367 +166 Central (5) | Eagle_Creek_AP |16.58 +4.43 42 1472 +109 Greenfield |20.52 +7.56 45 1391 +104 Indianapolis_AP |16.22 +4.07 38 1532 +169 Indianapolis_SE |19.52 +7.11 38 1381 +43 Tipton_Ag |13.88 +1.76 38 1267 +111 East Central (6)| Farmland |13.09 +0.71 43 1317 +202 New_Castle |16.43 +3.02 34 1143 -2 Southwest (7) | Evansville |17.15 +4.00 33 1808 +173 Freelandville |17.81 +4.26 33 1604 +170 Shoals |19.34 +4.86 34 1506 +134 Stendal |19.69 +4.96 33 1667 +148 Vincennes_5NE |19.47 +5.92 35 1638 +204 South Central(8)| Leavenworth |16.68 +2.03 30 1609 +236 Oolitic |22.34 +8.58 42 1455 +157 Tell_City |17.82 +3.07 26 1893 +358 Southeast (9) | Brookville |17.99 +4.95 35 1468 +263 Milan_5NE |23.41 +10.37 42 1256 +51 Scottsburg |19.49 +6.06 38 1494 +72 ------------------------------------------------------------- DFN = Departure From Normal (Using 1961-90 Normals Period). GDD = Growing Degree Days. Precipitation (Rainfall or melted snow/ice) in inches. Precipitation Days = Days with precip of .01 inch or more. Air Temperatures in Degrees Fahrenheit. Copyright 2002: AWIS, Inc. All rights reserved. The above weather information is provided by AWIS, Inc. For detailed ag weather forecasts and data visit the AWIS home page at www.awis.com or call toll free at 1-888-798-9955. The INDIANA CROP WEATHER REPORT (USPS 675-770), (ISSN 0442-817X) is issued weekly April through November by the Indiana Agricultural Statistics Service, 1435 Win Hentschel Blvd, Suite B105, West Lafayette IN 47906-4145. Second Class postage paid at Lafayette IN. For information on subscribing, send request to above address. POSTMASTER: Send address change to the Indiana Agricultural Statistics Service, 1435 Win Hentschel Blvd, Suite B105, West Lafayette IN 47906-4145. Source: Indiana Agricultural Statistics Service