in-crop-weather State Indiana Crop Weather Week Ending Date July 16, 2006 Issue IN-CW2906 Agricultural Summary Winter wheat harvest continues to make good progress for the entire state, according to the Indiana Field Office of USDA's National Agricultural Statistics Service. Many parts of the state received a much needed rain just as the corn began to tassel. Soybean plant development continues to vary but have seen improvements due to rainfall. Field Crops Report There were 3.7 days suitable for field work. Corn condition is rated 65 percent good to excellent compared with 39 percent last year at this time. Forty-three percent of the corn acreage has silked compared to 59 percent last year and 46 percent for the 5-year average. Soybean condition is rated 61 percent good to excellent compared with 43 percent last year. Thirty-three percent of the soybean acreage is blooming compared to 60 percent last year and 47 percent for the 5-year average. Harvest of winter wheat is 94 percent complete compared to 96 percent last year and 91 percent for the 5-year average. By area, wheat harvest is 88 percent complete in the north, 96 percent in the central, and 99 percent in the south. Second cutting of alfalfa hay is 70 percent complete. Major activities during the week included: attending county fairs, spraying chemicals, baling hay and straw, double cropping after wheat and mowing roadsides and ditches. Livestock, Pasture and Range Report Pasture condition is rated 10 percent excellent, 61 percent good, 24 percent fair, 4 percent poor and 1 percent very poor. No reports of any livestock issues. Crop Progress Table ------------------------------------------------------- : This : Last : Last : 5-Year Crop : Week : Week : Year : Avg ------------------------------------------------------- Percent Corn Silked 43 13 59 46 Corn in Dough 2 NA 4 3 Soybeans Blooming 33 12 60 47 Soybeans Podding 5 NA 11 11 Winter Wheat Harvested 94 70 96 91 Alfalfa Second Cutting 70 53 78 64 Crop Condition Table ------------------------------------------------------------ : Very : : : : Excel- Crop : Poor : Poor : Fair : Good : lent ------------------------------------------------------------ Percent Corn 1 6 28 53 12 Soybeans 2 7 30 53 8 Pasture 1 4 24 61 10 Soil Moisture & Days Suitable for Fieldwork Table -------------------------------------- : This : Last : Last : : Week : Week : Year : -------------------------------------- Percent Topsoil Very Short 1 4 16 Short 7 19 34 Adequate 68 70 47 Surplus 24 7 3 Subsoil Very Short 1 3 18 Short 9 15 38 Adequate 77 74 44 Surplus 13 8 0 Days Suitable 3.7 5.9 3.7 Contact information --Greg Preston, Director --Jamie Price, Agricultural Statistician E-Mail Address: nass-in@nass.usda.gov http://www.nass.usda.gov/Statistics_by_State/Indiana --------------------------------------------------------------------------- Other Agricultural Comments And News TASSEL EMERGENCE & POLLEN SHED * Corn produces individual male and female flowers on the same plant. * The tassel represents the male flower of the corn plant. Over the next several weeks, the Indiana corn crop will move into the critical flowering stages of pollen shed and silk emergence. Success or failure during this period of the corn plant's life will greatly influence the potential yield at harvest time. As important as this process is to the determination of grain yield, it is surprising how little some folks know about the whole thing. Rather than leaving you to learn about such things "in the streets", I've developed this article and the accompanying one on silking (Nielsen, 2005b) that describe the ins and outs of sex in the corn field. Remember that corn has both male flowers and female flowers on the same plant (a flowering habit called monoecious for you trivia fans.) Interestingly, both flowers are initially bisexual (aka "perfect"), but during the course of development the female components (gynoecia) of the male flowers and the male components (stamens) of the female flowers abort, resulting in tassel (male) and ear (female) development. Technically, growth stage VT occurs when the last branch of the tassel emerges from the whorl (Ritchie et al., 1993). Portions of the tassel may be visible before the maximum leaf stage (final visible leaf collar) has occurred. Plant height is nearly at its maximum at growth stage VT. Pollen shed may begin before the tassel has completely emerged from the whorl. The corn plant is most vulnerable to hail damage at growth stage VT since all of its leaves have emerged. Complete (100%) leaf loss at growth stage VT will usually result in complete (100%) yield loss by harvest. Even if pollination is successful, the ear shoots will usually die because few leaves remain to produce the necessary carbohydrates (by photosynthesis) to complete grain fill. An individual tassel produces approximately 6,000 pollen-bearing anthers, although hybrids can vary greatly for this number. The anthers are those 'thingamajigs' that hang from the tassel during pollination. Under a magnifying lens, anthers look somewhat like the double barrel of a shotgun. Approximately 1,000 individual spikelets form on each tassel and each one bears two florets encased in two large glumes. Each floret contains three anthers. An anther and its attached filament comprise the stamen of the male flower. As these florets mature, elongation of the filaments helps exsert the anthers from the glumes. Pollen is dispersed through pores that open at the tips of the anthers. Pollen shed usually begins in the mid-portion of the central tassel spike and then progresses upward, downward and outward over time. Anthers typically emerge from the upper floret of the pair first, while those from lower floret typically emerge later the same day or on following days. Spent anthers eventually drop from the tassel and are sometimes mistaken for the pollen when observed on the leaves or ground. The yellow or white "dust-like" pollen that falls from a tassel represents millions of individual, nearly microscopic, spherical, yellowish - or whitish translucent pollen grains. Estimates of the total number of pollen grains produced per tassel range from 2 to 25 million. Each pollen grain contains the male genetic material necessary for fertilizing the ovary of one potential kernel. The outer membrane of a pollen grain is very thin. Once dispersed into the atmosphere, pollen grains remain viable for only a few minutes before they desiccate. Yet, with only a 15 mph wind, pollen grains can travel as far as 1/2 mile within those couple of minutes. Therein lies the concern of the potential for pollen "drift" from a transgenic corn field to an adjacent non-transgenic corn field and the risk of transgenic "contamination" of grain intended for non-transgenic markets. The good news is that recent research suggests that the overwhelming majority of a corn field's pollen load is shed in the field itself. All of the pollen from a single anther may be released in as little as three minutes. All the anthers on an individual tassel may take as long as seven days to finish shedding pollen, although the greatest volume of pollen is typically shed during the second and third day of anther emergence. Because of natural field variability in plant development, a whole field may take as long as 14 days to complete pollen shed. Peak pollen shed usually occurs in mid-morning. Some research indicates that pollen shed decreases after temperatures surpass 86ºF. A second "flush" of pollen often occurs in late afternoon or evening as temperatures cool. Pollen shed may occur throughout most of the day under relatively cool, cloudy conditions. Weather conditions influence pollen shed. If the anthers are wet, the pores will not open and pollen will not be released. Thus, on an average Indiana summer morning following a heavy evening dew, pollen shed will not begin until the dew dries and the anther pores open. Similarly, pollen is not shed during rainy conditions. Cool, humid temperatures delay pollen shed, while hot, dry conditions hasten pollen shed. Extreme heat stress (100ºF or greater) can kill corn pollen, but fortunately the plant avoids significant pollen loss by virtue of two developmental characteristics. First of all, corn pollen does not mature or shed all at once. Pollen maturity and shed occur over several days and up to two weeks. Therefore, a day or two of extreme heat usually does not affect the entire pollen supply. More importantly, the majority of daily pollen shed occurs in the morning hours when air temperature is much more moderate. A listing of "Related References" for this article can be viewed at: http://128.210.99.160/entomology/ext/targets/p&c/PandC16_2006.pdf, page 8. Bob Nielsen, Department of Agronomy, Purdue University. The INDIANA CROP & WEATHER REPORT (USPS 675-770), (ISSN 0442-817X) is issued weekly April through November by the USDA, NASS, Indiana Field Office, 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 USDA, NASS, Indiana Field Office, 1435 Win Hentschel Blvd, Suite B105, West Lafayette IN 47906-4145. --------------------------------------------------------------------------------- Weather Information Table Week ending Sunday July 16, 2006 ----------------------------------------------------- | Past Week Weather Summary Data |--------------------------------- Station | Air | | Avg | Temperature | Precip. |4 in. |---------------|------------|Soil |Hi |Lo |Avg|DFN| Total|Days |Temp ----------------------------------------------------- Northwest (1) Chalmers_5W 91 64 77 +3 1.25 3 Francesville 91 66 76 +4 4.37 5 Valparaiso_AP_I 92 66 75 +3 2.47 5 Wanatah 91 62 74 +3 3.12 3 81 Winamac 91 66 76 +3 2.96 3 76 North Central(2) Plymouth 91 67 76 +3 1.68 2 South_Bend 90 65 75 +3 3.11 2 Young_America 90 66 76 +3 1.15 2 Northeast (3) Columbia_City 91 63 75 +3 1.95 3 73 Fort_Wayne 92 63 77 +3 1.61 3 West Central(4) Greencastle 91 61 75 -1 0.60 3 Perrysville 92 63 77 +3 1.48 3 78 Spencer_Ag 92 61 76 +1 2.34 4 Terre_Haute_AFB 93 62 77 +2 1.35 3 W_Lafayette_6NW 91 66 77 +4 1.62 3 80 Central (5) Eagle_Creek_AP 92 67 78 +3 1.76 3 Greenfield 91 64 76 +2 1.90 4 Indianapolis_AP 92 65 77 +2 2.62 3 Indianapolis_SE 90 66 76 +0 1.59 4 Tipton_Ag 90 64 76 +3 1.58 2 79 East Central(6) Farmland 90 63 76 +4 0.74 4 78 New_Castle 91 63 75 +3 0.67 3 Southwest (7) Evansville 92 65 79 +2 4.99 4 Freelandville 93 66 78 +2 0.46 2 Shoals 91 61 77 +2 1.76 3 Stendal 93 67 79 +3 4.02 4 Vincennes_5NE 92 66 78 +3 1.25 3 77 South Central(8) Leavenworth 91 64 77 +3 2.58 5 Oolitic 91 60 76 +2 2.36 5 77 Tell_City 91 61 78 +1 3.14 4 Southeast (9) Brookville 95 63 77 +4 2.00 2 Greensburg 90 66 78 +4 1.59 3 Scottsburg 91 65 78 +3 2.15 5 ---------------------------------------------------- Weather Information Table (Continued) Week ending Sunday July 16, 2006 ------------------------------------------------ Accumulation -------------------------------- April 1, 2006 thru Station July 16, 2006 -------------------------------- Precipitation |GDD Base 50oF -------------------------------- | | | | Total | DFN |Days|Total| DFN ------------------------------------------------- Northwest (1) | Chalmers_5W |16.14 +2.89 37 1449 -69 Francesville |20.14 +6.69 43 1394 +10 Valparaiso_AP_I | 9.88 -4.30 33 1433 +85 Wanatah |12.59 -1.05 36 1287 +4 Winamac |14.16 +0.71 34 1404 +20 North Central(2)| Plymouth |11.87 -2.21 39 1321 -122 South_Bend |13.03 -0.14 40 1395 +64 Young_America |16.95 +4.05 42 1472 +63 Northeast (3) | Columbia_City |14.38 +1.12 43 1309 +45 Fort_Wayne |16.64 +4.43 43 1437 +38 West Central(4) | Greencastle |16.03 +1.18 41 1447 -163 Perrysville |13.66 -0.83 41 1634 +129 Spencer_Ag |18.39 +3.06 49 1542 +40 Terre_Haute_AFB |13.04 -1.43 41 1682 +74 W_Lafayette_6NW |15.08 +1.77 43 1525 +112 Central (5) | Eagle_Creek_AP |17.40 +3.93 46 1659 +68 Greenfield |19.60 +5.05 49 1466 -46 Indianapolis_AP |17.57 +4.10 47 1669 +78 Indianapolis_SE |17.83 +3.97 46 1448 -120 Tipton_Ag |17.97 +4.63 50 1359 -6 East Central(6) | Farmland |16.64 +3.18 49 1321 -1 New_Castle |16.41 +1.74 45 1388 +36 Southwest (7) | Evansville |18.85 +4.49 40 1986 +96 Freelandville |11.98 -2.83 37 1796 +127 Shoals |19.48 +3.56 41 1707 +109 Stendal |20.93 +4.94 41 1979 +217 Vincennes_5NE |19.21 +4.40 47 1828 +159 South Central(8)| Leavenworth |22.57 +6.48 52 1743 +145 Oolitic |16.46 +1.37 43 1537 +19 Tell_City |21.82 +5.72 43 1980 +200 Southeast (9) | Brookville |16.35 +1.96 40 1581 +160 Greensburg |18.08 +3.46 44 1664 +175 Scottsburg |21.65 +6.81 48 1739 +83 ------------------------------------------------------------------ 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 2006: Agricultural Weather Information Service, 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