Strategies to convert exotic grass dominated pastures to tall grass prairie communities. Objectives. The Situation.

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1 Thomas G. Barnes, Ph.D. Extension Professor Department of Forestry Strategies to convert exotic grass dominated pastures to tall grass prairie communities Objectives Summarize a decade of research & experience in re-creating, restoring, and rehabilitating grasslands using herbicides Provide some recommendations for various exotic grass conversion to native warm season grasses The Situation One of most endangered ecosystems Conversion to agriculture Degradation from exotics KY < 3 million acres Several thousand Keys to Success 1. Purchase Good Quality Seed 2. Make your own mix to fit site conditions 3. No-till more successful than conventional tillage 4. Must control existing vegetation prior to seeding 5. Handle weed problems before seeding 6. Weed control after seeding is essential 7. Spring seeding more successful than dormant 8. Drilling more successful than broadcasting 9. Make sure get good seed/soil contact 1. Do not seed too deep 11. Pray for rain The Strategies With New Herbicide Technology 1. Restoration Using Herbicides Without Seeding 2. Conversion Using Herbicides & No- Till Technology 3. Conversion Using Conventional Tillage With Herbicides For Weed Control 1

2 Possible to establish on the most difficult of sites, such as Appalachian stripmines,, but you MUST pay attention to detail and plan appropriately PATIENCE IS A VIRTUE!!! Issue One: Seed Quality You get what you pay for no cheap mixes Take sample of every bag and send to UK regulatory services for testing Year One Year Three Issue Two: Seed Mixes Total Rate for Restoration: 8 1 lbs PLS 6% forb 4% grass Wildlife Habitat 4 6 lbs PLS 6% grass 4% forb Grazing 1 12 lbs PLS Pure grass stand Eastern gama,, big bluestem Biomass 1 12 lbs PLS Pure grass stand - switchgrass Use local genotype if possible If not possible, use closest source Match species to site conditions Seeds & Seeding The Replacement Species Warm Season Grasses Big Bluestem Indian Grass Little Bluestem switchgrass usually never more than ½ lb PLS/acre AT MOST,, usually reserve wet sites Eastern gama (need deep, well-drained, not Plateau tolerant) Sideoats grama Tall dropseed Northern Dropseed Other Andropogon spp. Cool Season Elymus spp.. (in more northern environments also have Stipas) Plateau Tolerant Forbs Black-eyed Susan Lance-leaf coreopsis Illinois Bundleflower Purple & White Prairie Clover Blanket Flower Partridge Pea More being added pre-emergent emergent & post emergent 2

3 Avg # seedlings/sq m Lexington 4 oz imazapic trmt conventional till Amorpha canescens A. laevis A. novae-angliae angliae Baptisia lactea D. canadense D. illinoense Heliopsis helianthoides Ratibida pinnata Rudbeckia fulgida Solidago rigida Post-emergent Plateau Tolerant Forbs (J. Natural Areas Jan. 27) Eupatorium coelestinum, hyssopifolium, serotinum, fistulosum Aster pilosus, dumosus,, patens, ontarionensis, lateriflorus,, novae-angliae angliae Solidago altissima, rugosa, odorata, nemoralis Asclepias tuberosa, viridis, viridiflorus Silphium terebinthenaceum, pinnatifidum Rudbeckia hirta, fulgida, Ratibida pinnata, Helianthus divaricatus,, H. atrorubens Issue Three: No - till Preserves existing moisture Better seed-soil soil contact Less weed pressure Based on premise that you use herbicides to control existing vegetation as completely as possible & provide for residual weed control Issue Four: Killing Existing Vegetation The Problem Species Cool Season Grasses Tall Fescue KY Bluegrass Smooth Brome Quackgrass Reed Canary Grass 3

4 The Problem Species Warm Season Grasses Common Bermuda Grass Bahia Grass Old World Bluestems The Primary Herbicides Used Glyphosate (Round up) Imazapic (Plateau or Journey) Imazapyr (Arsenal or Stalker) Sulfosulfuron (Outrider) Graminicides (Select, Fusilade, Fusion, etc.) Using Herbicides Using Herbicides to Remove Tall Fescue Make sure to always follow the label (it s s the law) None of herbicides used or recommended are restricted use Make sure the equipment is calibrated properly 1. Which herbicide(s) 2. What rate 3. Timing - critical Killing Existing Vegetation IMPORTANT: Burn (graze, hay) fescue Newer herbicides work by shutting down photosynthesis Burning stimulates the grasses, removes litter to get maximum herbicide leaf tissue contact Burning Burning alone will NOT kill fescue 4

5 % Fescue Remaining Effect of Imazapic on Fescue Reduction With Burning % Fescue Remaining Effect of Imazapic on Fescue Reduction Without Burning fall 99 spring sum control water Burn Burn water.7 Pl.7 + NIS.14 Pl.14 Pl NIS.18 Pl.18 Pl NIS fall 99 spring sum control water.7 Pl.7 + NIS.14 Pl.14 Pl NIS.18 Pl.18 Pl NIS Initial Studies in Tall Fescue Fescue Control in Spring vs. Fall Using Glyphosate % Fescue Remaining 1 Prior to release of newer herbicides, glyphosate was only option available Multiple studies (more than 5) showed single spring application at label rate (2 quarts per acre) was sufficient for an excellent kill Fayette Muhlenberg Caldwell Control Spring Control Fall % tall fescue after spring herbicide application Adkins thesis 26 % tall fescue after summer herbicide application Adkins thesis griffith julian griffith julian 5

6 % tall fescue after fall herbicide application Adkins thesis griffith julian Very similar results in following papers Madison, Barnes, & Sole 21: Wildlife Society Bulletin Washburn, Barnes, & Sole 21: Wildlife Society Bulletin Washburn & Barnes 2: Weed Tech Barnes 27: Natural Areas Journal Ruffner & Barnes 24: Proceedings North American Prairie Conference Herbicide Comparisons For Killing Tall Fescue % Fescue Remaining Kleber Taylorsville Washington control Sethoxydim Clethodim 1 Clethodim 12 Imazapic Glyphosate Killing Fescue With Clethodim & Glyphosate % Fescue Remaining week 4 week 6 week 12 week control 1 oz 12 oz 16 oz Roundup Controlling Tall Fescue Multiple studies indicate Imazapic (Plateau or Journey) at label rate with MSO & 2.5 lbs AMS/acre tank mix will kill tall fescue in spring, fall, and even during dormant season (mid-summer) Burning increases efficacy in removing existing litter, get good plant herbicide contact With Plateau use methylated seed oil as a surfactant Added advantage is residual weed control Controlling Tall Fescue Continued Glyphosate at 2 quarts per acre is also equally effective Best control in spring but can be used in fall but will most likely need to reapply in spring Cheaper than Imazapic No residual chemical no residual weed control 6

7 Controlling Tall Fescue Continued Outrider at 2 oz per acre is also quite effective in spring and can be used in the fall Advantage in using it post-emergent to kill Johnsongrass (1.5 oz/acre) Only stays in soil for about 5 days, no residual weed control Controlling Tall Fescue Continued Graminicides can be used but are not as effective, cost equivalent to Imazipic or Sulfosulfuron,, might need multiple applications No residual soil activity, therefore no residual weed control Fescue Conversion Using No-till Several Studies Summary Burn early Spring Apply 12 oz Imazapic about month later (mid-april) when tall (add 1 qt MSO & 2.5 lbs AMS / ac in tank) 2 gallon/acre spray rate Seed from May through June Kentucky Bluegrass Current Studies in South Dakota and Kentucky % KY Bluegrass cover after fall herbicide treatment (removing & restoring unbroken native grassland in SD) % KY Bluegrass cover after spring herbicide treatment (removing & restoring unbroken native grassland in SD) control arsnl arsnl pla out out split out plat control arsnl arsnl pla out out split out plat % bluegrass % bluegrass 7

8 % KY Bluegrass cover in the spring after a fall herbicide treatment control out out + ru ru journey plateau arsenal arsenal % KY bluegrass after spring herbicide application in Central KY Adkins thesis % bluegrass griffith julian % KY bluegrass after summer herbicide application in Central KY Adkins thesis griffith julian % KY Bluegrass after fall herbicide application in Central KY Adkins thesis blk 2 gw blk 2 js Issues Five & Six: Weed Control Time to begin is year prior to treatment to evaluate potential weed issues Example, Thistle (nodding or Canada), Johnsongrass Must control these problems prior to doing a conversion Also will dictate a single seeding or a two-stage seeding Issues Five & Six: Weed Control Johnsongrass (1.5 oz Outrider or 32 oz Journey = 12 oz Imazapic) Thistle (label rate for Crossbow or Milestone new DOW product has residual soil activity important for putting in forbs) 8

9 Use of Imazapic (Plateau or Journey) for Weed Control Advantage of using imazapic in burn- down is you get residual weed control No-till use 32 oz Journey or 12 oz Plateau Weed control for 6 days ragweed, foxtail grasses, crabgrass, etc. If using conventional tillage only need 8 oz Journey or 4 oz Plateau at seeding for weed control 6 Weeks Post-Planting Planting 12 oz Plateau No-till 2 Months Post-Planting Planting 12 oz Plateau No-till 2 quarts glyphosate + 4 oz seeding Year One % cover = 7% If You Are Doing Restoration or Have Thistle or Other Broadleaf Weed Issues Do a split seeding Seed grasses in spring Do weed control with crossbow, 2 4 D, Remedy, or Milestone depending on weed issue Seed forbs in fall Has the advantage of cold-moist stratifying forb seed 9

10 Issue Seven to Ten: Seeding Calibrate drill Use no-till drill Seed from Mid-April through June (if you get rain) Make sure seed no deeper than ¼ Get off tractor check to seed if seed is dropping tubes do & will plug Fluffy Seed Mix Grass & Forbs With Awns Together Put Larger & Legume Seeds in Box This is the proper seeding depth As much as 1/3 of the seed can lay on the top of the soil Prescription for disaster Must compact the soil prior to seeding 1

11 Establishment Using Conventional Tillage Prepare seedbed Cultipack or roll Seed Cultipack or roll Apply 4 6 oz Plateau Trtmt Data Supporting Recommendations Little Bluestem Big Bluestem Indian grass (plants/sq meter) Control oz oz oz Keys to Success 1. Purchase Good Quality Seed 2. Make your own mix to fit site conditions 3. No-till more successful than conventional tillage 4. Must control existing vegetation prior to seeding 5. Handle weed problems before seeding 6. Weed control after seeding is essential 7. Spring seeding more successful than dormant 8. Drilling more successful than broadcasting 9. Make sure get good seed/soil contact 1. Do not seed too deep 11. Pray for rain Questions? tbarnes@uky.edu Department of Forestry University of Kentucky Lexington, KY