CORN PRODUCTION ISSUES IN WESTERN ND

Transcription

1 CORN PRODUCTION ISSUES IN WESTERN ND

2 WHAT IS CORN? Corn is a warm season grass. Has its origins in the sub tropical climates. Prefers warm soils 85 degrees or higher. Very responsive to fertilizer. Multiple options for weed control. -GMO s glyphosate tolerant, glufosinate or both. -Conventional options.

3 MOISTURE Most of the corn production is dry land. Annual rainfall in western ND inches. Management practices matter!! No till. Strip till. Conventional.

4 NO TILL

5 STRIP TILL

6 CONVENTIONAL TILL

7 GROWING DEGREE UNITS After moisture the most limiting factor in corn production. Total GDU accumulation varies across western ND yr. avg. Williston Minot Bismarck Dickinson

8 SELECTING THE PROPER CRM Knowing the average GDU accumulation for your area is critical in selecting the proper CRM. Planting a hybrid with too long of a CRM can cause you to lose yield and quality. Planting a hybrid with too short of CRM can cause you to lose yield potential. Seed companies have no standard for rating the CRM of corn hybrids.

9 PLANTING Date Corn should be planted once the ground temperature has reached 50 F (maybe hard to accomplish this in northern areas of the state) Better to take a chance and seed early when you can still replant if a frost occurs than to have a frost affect you in the fall when no options exist.

10 PLANTING DEPTH Ideally corn should be seeded at 1 ½ to 2 inches. 1 ½ inches may be favorable when planting early into cool wet soils (high residue) Never plant shallower than 1 ½ inches!!! Planting should be done with a row planter.

11 PLANTING DEPTH RECOMMENDATIONS Set planting depth in the field with the planter at full speed. Check for good seed-soil contact. Slower planting speeds achieve more uniform planting depths. Utilize in-row residue management equipment where needed Utilize in-furrow seed depth control devices

12 TYPES OF NON-UNIFORM PLANT SPACING

13 UNEVEN PLANT SPACING

14 EVEN PLANT SPACING

15 DETERMINING PLANT POPULATION Stored soil moisture and average precipitation Productivity of the soil Fertility levels (willingness to fertilize) Does your hybrid have fixed or flexed type of ear?? Plant populations range from 18,000 to 28,000 on dry land, 32,000-35,000 irrigated.

16 MANAGEMENT TIPS Make sure the target pant population is high enough to maximize profitability. Typical seed corn germination is about 95%. Over plant by at least 5% to reduce the effects of germination-induced skips. Overplant for expected reductions due to insects and soil conditions Be sure the planter is properly adjusted and calibrated.

17 FERTILITY 100 Bushel corn crop requires: 120 lb. actual Nitrogen (1.2 per/bu) Phosphate 45 lb. /acre for soil testing low for P and 25 lb./acre for those testing medium. Potassium 15 lb./acre. Sulfur likely responsive on coarse soils. Zinc most responsive micronutrient.

18 MACRONUTRIENTS Nutrients essential to plant growth that are needed in large quantities. Nitrogen, Phosphate, Potassium, Sulfur, Magnesium and Calcium.

19 MICRONUTRIENTS Micronutrients are essential to plant growth and are needed in only very small quantities. Boron, Chlorine, Copper, Iron, Manganese Molybdenum and Zinc.

20 WHAT DOES A CORN PLANT REQUIRE 150 bu/acre corn crop requires 180 lb./acre of Nitrogen..25 lb./acre of Zinc. Should I be adding micronutrients? Micronutrients should only be added if You have done a soil or tissue test showing a deficiency in a particular micronutrient. You have met all of your macronutrient requirements.

21 NUTRIENT DEFICIENCIES N I T R O G E N P H O S P H O R U S

22 NUTRIENT DEFICIENCIES Z I N C S U L F U R

23 WEED CONTROL There are many options for controlling weeds in corn. Pre emergent herbicides-applied prior to planting or after planting but before the corn emerges. Post emergent herbicides-applied after the crop has emerged.

24 PRE EMERGENT HERBICIDES Advantages Stops weeds before they get a chance to compete with the corn. Gives you the ability to rotate your chemical modes of action. Disadvantages Require a rainfall for activation. Cost disadvantage over post options??

25 POST EMERGENT HERBICIDES Advantages Large percentage of corn grown is herbicide tolerant this allows for good crop safety and economical weed control. Allows you to see which particular weeds you are needing to control. Disadvantage Weed resistance and tolerance becoming a bigger issue with glyphosate.

26 WHAT IS THE BEST WEED CONTROL STRATEGY? Pre emergent herbicide followed by a post emergent herbicide to take out any escapes. Can I reduce my rate on pre emergent herbicide? No!!! Resistance and performance issues.

27 WHAT IS GOSS S WILT? Causal organism: Clavibacter michiganesis subsp. nebraskensis Diverse bacterial pathogen Resides in infected residue Opportunistic pathogen Requires injury to plant Wind sandblasting Hail - causes greatest risk for infection Infection by rain/irrigation splash Systemic May be confused with Stewart s wilt

28 Disease Triangle FAVORABLE ENVIRONMENT SUSCEPTIBLE HOST DISEASE PATHOGEN Crop monocultures High inoculum carryover High plant density Imbalanced fertility Ideal weather conditions Susceptible hybrids

29 HOSTS Major Hosts: Maize Secondary Hosts Sugarcane Sorghum Sudan grass Minor Hosts: Barnyard grass Triticale Wheat

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33 GOSS S INFLUENCE ON YIELD Yield reduction caused by premature death Severe leaf blight at early grain fill = greatest risk Hybrids with poor late season plant health suffer greatest losses Compounding effect Can lead to other disease problems Stalk rots Ear molds Causes harvest ability issues

34 GOSS S INFLUENCE ON YIELD Goss s Wilt causes premature death of corn Leaf blight phase reduces leaf area Consequences to grain fill

35 CONCLUSIONS Hybrid resistance is key defense Residue borne Full season hybrid have more natural tolerance Disease is here to stay Id Goss s vs Bacterial soft rot Hybrid knowledge and placement is critical

36 INSECTS PESTS IN CORN Wireworms Often attack small grains and other crops in ND. Larvae and adults move toward the soil surface during the spring once soil temperatures reach F. Larvae will move deeper into the soil as the soil surface warms.

37 CORN ROOT WORM Western corn rootworm and northern corn rootworm are the two primary species of significance in ND. Corn hybrids with rootworm BT have been on the market for several years. Soil applied insecticides are affective in controlling rootworm. Resistance to cry3bb1 documented.

38 EUROPEAN CORN BORER Very challenging pest to manage due to the lengthy emergence interval of the moths from overwintering in ND. Can have up to two generations in one season. Control greatly improved with introduction of first BT hybrids in the late 90 s. EPA concerned with IRM practices.

39 CONCLUSION ROTATION, ROTATION AND ROTATION!!! Rotate crops, avoid continuous seeding of any one particular crop. Rotate modes of action of herbicides and use multiple modes of action when possible. Rotate fungicides use different modes of action. Rotate insecticides use different modes of action.