Edge* in Today s Farming

Transcription

1 Edge* in Today s Farming Agronomy Update 2015 Lethbridge, Alberta 1

2 Dinitroaniline Chemistry BACKGROUND : CHEMICAL GROUP: Initially developed in the early 1970 s and 1980 s and applied pre-emergently in the spring or fall season prior to planting of canola, mustard, soy bean and legume crops. Ethalfluralin & Trifluralin Group 3 Mitotic Inhibitors- Prevent Mitosis (normal cell division). Impacted by lipid content in the seed coat. Does not enter the plant. Pre-emergent weed control- soil incorporated USE RATES: lbs a.i./acre depending on soil type FORMULATION: Primarily Granular 5% active. 2

3 How do the products work? Inhibits cell division- occurs in growing points or merristematic cells > Activity on germinating or emerging seedlings >Not effective as a post emergence treatment Weed seeds must be located in the treated soil layer. > This is different than Triallate which acts on the growing point of the wild oat as it grows through the treated layer 3

4 DNA Adsorption and Soils Molecules associate with the surface of soil particles. Bind to soil and organic mater and dissipates as a very slow moving gas. Organic matter and high clay content soils have high adsorption versus low organic matter coarse textured soils. Rate is dependant on soil type and season of application Not water mobile and does not leach 4

5 Dissipation Microbial degradation with warm temperature is the most significant means of breakdown. ½ life of 56 days and with safe rotation of wheat, barley, oilseed and legume crops. Risk to small seeded annual grasses Rate of dissipation is influenced by soil type(surface area), moisture, and soil temperature Secondary pathway of degradation is via photolysis- UV light 5

6 DNA- Affects of Soil Moisture Typically bound to the soil with little change over normal soil moisture ranges other than permanent wilting point or under flooded conditions. > Extreme flood conditions will increase desorption very rapidly because water molecules displace DNA products resulting in rapid degradation 6

7 Changing Trends in Farming Introduction of Herbicide Tolerant Canola varieties Adoption of zero till and minimum tillage practices Conserve moisture and prevent erosion Reduce fuel consumption Integration of glyphosate as a standard pre-seed practice Significant adoption of Groups 1,2 and 9 herbicide in pre-seed, fallow, oilseed, legume and cereal rotations. 7

8 Changing Trends in Farming Subsequent development of weed resistance: Virtually all kochia is Group 2 resistant Wild oat resistance to Group 1, and 2 graminicides Development of Group 9 Kochia resistance Growers looking at creative ways to introduce the use of different herbicide groups Used in conventional tillage and practices integrating use in direct/zero till seeding. 8

9 Status Today Use pattern in conventional tillage continues where the product must be incorporated 3-4 inches deep. Continued concerns with weed resistance which is causing reassessment of herbicide and crop rotations. Edge has recent PMRA re-evaluation which now allows for changes to use patterns and further crop submissions. To align with reduced tillage trends testing has been completed for Edge use in surface applications to fields that have been in reduced tillage practices. 9

10 Edge Surface Applications and Direct Seeding With adoption of no-to-low tillage practices less soil disturbance has resulted in weed seed concentrations in the top ½ inch of the soil Glyphosate has been an effective tool in pre-seed applications control early weed flushes. When Edge is applied to low disturbance fields <30%- weeds are now shallow and grow in treated layer 10

11 Surface Applied Use Control occurs within the Edge layer. If weeds germinate below this layer due to disturbance such as tillage control is erratic. 11

12 Edge and Direct Seeding Management Can be effective if: Land has been in a direct seeding system for at least 2 years with less than 30% soil disturbance. Applications occur in the fall or 7-10 days prior to seeding with a mild harrowing to assure granule soil contact. A glyphosate pre-seed burn down application is essential for weeds that emerge prior to the Edge fully activating. The less soil disturbance the better. Disc opener vs. wide openers.. Keep weeds on the soil surface. 12

13 Dinitroanaline Symptoms 13

14 Use Rates for Edge Granular Spring rates: In either surface applied or conventional applications 15 lbs/acre- coarse textured & low organic matter (2-4%) soils 20 lbs/acre in medium texture soils with organic matter between 4-6%. Fall rates: 20 lbs/acre in coarse textured or low organic matter (2-4%) soils 25 lbs/acre in medium texture soils with organic matter between 4-6%. 14

15 Crop Selectivity- Major Crops Edge: Alfalfa establishment Canola Beans Peas Soybean Beans Safflower Sunflower Yellow Mustard Sunflower 15

16 Weed Sensitivity-(Non-labeled) High Sensitivity Wild buckwheat Chickweed Pigweed Cow cockle Foxtail Purslane Barnyard grass Corn spurry Small annual grasses Down Brome Japanese Brome Moderate Sensitivity Lamb s quarters Wild oats Volunteer Cereals Kochia Smartweed Hemp nettle Cleavers Volunteer Barley Russian Thistle Nightshade-Black Nightshade- American 16

17 Edge and Direct Seeding... Research Findings Performs well if: The land has been in a direct seeding system for at least 2 years and soil disturbance is less than 30%. Less is better Equipment that minimizes soil disturbance has been used. Disc opener vs. spoons. Used in conjunction with pre-seed burn down application to control early emerging weeds. 18

18 Edge Use Rates Use rates are identical to conventional tillage. 1 > lbs in the spring and lbs/acre in the fall > Lightest rates used in low organic matter coarse textured soils Good soil contact is essential; harrow sloped backwards helps to helps granules reach soil surface with minimal disturbance Spring applications require application was at least 10 days prior to seeding to optimize dispersion A pre-seed burn down treatment using products like VP MAX II (glyphosate) is essential to control emerged weeds 19

19 Weed Efficacy- Direct Seeding Wild Oats AVEFA XX(X) Volunteer Wheat TRZAS XXX Green Foxtail SETVI XXX(X) Wild Buckwheat POLCO XXX Lamb's-Quarters CHEAL XXX Kochia KCHSC XXX Cleavers GALAP XXX XXXX= Exceeds current standards XXX= Commercial Control XX= Suppression 20