May 12, 2016
Volume 7, Issue 2
Cont. pg. 2
The University of Maryland, College of Agriculture and Natural Resources programs are open to all and will not discriminate against anyone because of race, age, sex, color, sexual orientation, physical or mental disability, religion, ancestry, or national origin, marital status, genetic information, or political affiliation, or gender identity and expression.

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Agronomy News - May 12, 2016
Planting
Date
1-Apr
10-Apr
20-Apr
30-Apr
9-May
19-May
29-May
8-Jun
10
54
57
58
58
55
50
44
35
15
68
70
71
70
68
63
56
47
Population (1000 plants/acre)
20 25 30
------------ % of maximum yield --------------
78
81
81
88
91
91
95
97
97
35
99
100
100
80
77
72
65
56
89
86
80
73
63
95
91
85
77
67
97
93
86
78
67
40
99
100
99
96
91
84
75
64
3

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Adult Asian tiger mosquito.
(Photo: Susan Ellis, Bugwood.)
Mosquito larvae and pupa floating with their breathing tubes at the surface of the water.
(Photo: University of Maryland)
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Dr. Joanne Whalen, Extension IPM Specialist, University of Delaware (WCU—May 6, 2016)
Alfalfa: Be sur e to check for weevil adults within one week of cutting. A stubble tr eatment will be needed if you find 2 or more weevils per stem.
Field Corn: Watch for both cutwor ms and slugs feeding in newly emer ged fields. Sample through the 5 leaf stage for cutworms. Look for slime trails on the leaves for evidence of slugs.
Small Grains : Aphids, gr ass sawflies, tr ue ar mywor ms and cer eal leaf beetles can be found in fields throughout [ Delaware ].

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Wet conditions across Maryland have increase the risk of sidewall compaction. Below are some points pulled from Mike Staton’s article about sidewall compaction. You can also read the full original article here.
Sidewall compaction includes all soil compaction and soil smearing in and around the seed furrow and can restrict root growth and reduce crop yields. It will be the most detrimental when the soil becomes dry after planting. There are several methods for determining if the soil is too wet to plant.
Some tips from Mark Hanna (ag engineer, Iowa State) and Paul Jasa (ag engineer, Nebraska) for assessing planting conditions:
 From the surface of the soil, form a ball. You may either throw this ball across the field or drop it in place (from waist high). If it stays mostly intact, your soil is too wet to plant.
 Take a similar soil sample in your hand and squeeze the soil in your fist and use your thumb and forefinger to form a ribbon of soil. If the ribbon extends beyond 3 inches before breaking off, the soil is probably too wet to plant. Additionally, you may squeeze the soil in your fist. If moisture and soil cling to your hand, the field is too wet to plant.
 If soil is building up on the rubber wheels, the seed furrow is smearing or not closing with minimal down pressure, the soil is too wet to plant.
Jasa also provides some excellent recommendations for reducing sidewall compaction:
 Reduce the down pressure on both the gauge wheels and the closing wheels.
 Try to leave some crop residue over the row to delay soil drying and opening of the seed furrow.
 Level the planter from front to rear or possibly operate it slightly tail down to improve seed-to-soil contact and seed furrow closing.
 Use seed firmers to improve seed-to-soil contact when using two spoked closing wheels per row to breakup sidewall compaction.
 Consider adding just one spoked closing wheel per row. This will break up the sidewall compaction on one side of the furrow and close the seed furrow more effectively in a wide range of conditions.
 Staggering the closing wheels will reduce the potential for the seed furrow to open up as the soil dries. If using one spoked wheel and one standard rubber wheel, place the spoked wheel in front.

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Some corn finds its way through cold wet weather on the lower eastern shore

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Scott A. Minnick, Meteorologist - NOAA - National Weather Service
Wakefield, VA
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Current rainfall may have reduced these conditions for the week of May 11th.

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