Volume 11, Issue 3
April 11, 2003
Volume 11, Issue 3
April 11, 2003
Fruit
Fruit Insects
-
Section 18 Approved for Provado
on Stone Fruits.
Provado 1.6F has been approved for use on peaches,
nectarines, plums and apricots in
A maximum of 4 applications
at the rate of 5-6 fl. oz. of product/A (0.06-0.08 lbs. a.i./acre)
of Provado 1.6F may be made by ground equipment. No more that 24 ounces of the product (0.32
lbs a.i.) may be applied per acre per year.
Vegetables
Watermelon
Promotion –
The National Watermelon Promotion Board has received approval from the USDA for a new logo that emphasizes watermelon as the “lycopene leader in fresh produce.” Research has indicated that lycopene, a cartenoid, may help reduce the risk of prostrate cancer and heart disease. Another good reason for consumers to buy Delmarvalous watermelons.
Wet Conditions
and Potato Weed Control Decisions –
The continuing wet conditions have obviously delayed much of the potato planting progress. In some cases, the weather may have eliminated the opportunity for pre-emergence treatments of herbicides. However, there are excellent post-emergence materials available.
If no pre-emergence materials were applied, a Matrix (rimsulfuron) and Sencor (metribuzin) combination will control many grass and broadleaf weed species. While the Matrix rate is 1 ounce/acre, a reduced rate of Sencor (metribuzin) at 1/3 lb./acre should be used when mixed with Matrix. Use non-ionic surfactant at 1 quart per 100 gallons of spray. Always check the label for additional instructions and restrictions. This must be applied before the potatoes are 14 inches tall. Of course, the earlier the application, the better the weed control.
The post-emergence grass materials, Select or Poast, can also be used as separate applications to control escaped grasses.
Vegetable Diseases
–
Ozone injury on watermelon.
Bifacial necrosis of old watermelon leaves.
(Mid-August.)
Photo
taken from the USDA-ARS, North Carolina State University Air Quality Research
Unit at the following address:
http://www.ces.ncsu.edu/depts/pp/notes/Ozone/o3waterm.html
Ozone
Damage in Watermelons.
Ozone injury to
watermelons is common in
Grain Marketing Highlights -
Supply and Demand Report Viewed as
Uneventful
Commodity
analysts are reporting no big surprises from the April 10th Supply and Demand
report. The numbers most watched in this report were ending stocks for
Corn
ending stocks are now listed at 1.009 billion bushels vs. the average trade
guess of 999 million bushels. Ending stocks for corn were reported to be 5
million bushels less than last month's estimate.
Soybean
ending stocks are down to 145 million bushels, vs
trade guesses ranging from 125 to 150 million bushels. Soybean stock estimates
are down 15 million bushels from last month.
Wheat
stocks are down 20 million bushels from last month. The decrease in wheat
stocks, now placed at 445 million bushels is due primarily to a 25 million
bushel increase in domestic feed and residual use and a 5 million bushel
increase in imports on the supply side.
CBOT Launches Mini Agricultural Futures
Contracts
The
Chicago Board of Trade launched CBOT mini corn, wheat, and soybean futures
contracts on Monday, April 7. The trading hours for these 1,000 bushel
contracts will be from
Is It Too Late to Apply Nitrogen to Small Grains? - Richard W. Taylor, Extension Agronomist; rtaylor@udel.edu
;
The question being raised after the most recent period of
bad weather is if it still is worth while fertilizing small grains. An important component of the answer is the
determination of the stage of growth of the crop. Where you haven’t been able to apply
fertilizer yet, you should take the opportunity to scout a field for the crop’s
growth stage while you wait for it to dry.
Examine a number of plants across the field and determine growth stage
by looking closely at the primary tillers on each plant. Check tillers to see if you can feel a
swelling that indicates node development.
Another way is to pull back leaf sheaths to expose the growing point and
see if more than one or two internodes (the space between two nodes) are
present. Also, observe how far above the
soil surface the growing point is. The
jointing stage of growth begins when the first node appears above the soil
surface and jointing progresses as more and more nodes occur above the soil
surface until boot stage when the seed head can be felt within the leaf
sheaths.
Once the space between the nodes begins to lengthen and
pushes the growing point that ends in the seed head above the soil surface, the
likelihood of doing at least some damage to the crop by driving across a field
to spread fertilizer is great. After
several internodes are visible, the chance of having a large impact on yield by
applying nitrogen (N) diminishes.
Another helpful indicator will be the intensity or greenness of the crop
or signs of N deficiency on the lower leaves.
The number of leaves per plant showing N deficiency symptoms relates to
the amount of N stress and that corresponds to loss of yield potential. When combined with plants at later stages of
development (late jointing or early boot), the damage caused by N stress
reaches the point where additions of N will no longer boost yields enough to be
profitable. The earlier you can apply N
the more yield response you are likely to see.
By boot stage, N will have little impact on yield potential although it
can still influence the grain N content.
Another question asked is whether wheat that recently came
up will yield? This question is harder
to answer because wheat requires a period of cold temperatures to change it
from vegetative state to a reproductive state.
Winter wheats require more cold weather than
spring wheats and southern varieties of winter wheat
can be switched to a reproductive state by fewer days of cold than varieties
developed further north. The problem
with deciding if a field will move to the development of grain (yield) is knowing when the crop germinated enough for the cold
temperatures to begin the process of vernalizing the
crop and switching it to a reproductive state.
With a microscope or a very good hand lens (and good eyesight), you
might be able to dissect plants and identify the developing panicle if it has
switched to the reproductive state. At
the growing point even when it is very tiny, you can identify the developing
panicle or seed head since it looks like a miniature wheat head. Even if you find that the crop has vernalized, the yield potential is an open question. Experience suggests wheat that emerges in
late February can produce 50 to 60 bu/A but we’ve not had experience with wheat emerging later
than that date.
Avoiding Leaf Burn from UAN on
Small Grains - Richard W. Taylor, Extension Agronomist;
rtaylor@udel.edu;
Several years ago Ron Mulford, the
farm manager for
If you have to apply UAN under warm conditions, you may want
to follow the guidelines below to possibly reduce the potential for leaf
burn. Since weather conditions may be
forcing many producers to apply N much later than they like, preventing even
the mildest of stress such as the temporary leaf burn UAN can cause can be
worth the extra effort.
|
Table 1. Approximate dilutions for UAN solutions
when topdressing small grain to reduce the potential for leaf burning under
warm conditions (60˚F and higher). |
|||
|
Gallons of UAN |
Gallons of Water |
N Application Rate |
Total solution
volume |
|
Lb N/a |
Gallons/acre |
||
|
28% UAN |
|||
|
13.4 |
None |
40 |
13.4 |
|
16.8 |
4.2 |
50 |
21 |
|
20.1 |
4.9 |
60 |
25 |
|
23.5 |
5.5 |
70 |
29 |
|
26.8 |
6.2 |
80 |
33 |
|
30% UAN |
|||
|
12.3 |
None |
40 |
12.3 |
|
15.4 |
4.6 |
50 |
20 |
|
18.5 |
5.5 |
60 |
24 |
|
21.6 |
6.4 |
70 |
28 |
|
24.6 |
7.4 |
80 |
32 |
|
32% UAN |
|||
|
11.3 |
None |
||