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 86F. 
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 (100F 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