Practical Applications

Transcription

1 Practical Applications wsm.wsu.edu/discovery/index.php/tag/cheatgrass/ Rachel Mealor Extension Range Specialist Department of Renewable Resources and Brian Mealor Extension Weed Specialist Department of Plant Sciences

2 PRACTICAL APPLICATIONS: PART I Tools and Techniques to Manage Cheatgrass

3 Road Map What are we doing to combat cheatgrass? common tools used for cheatgrass management and control Projects already completed Developing a strategy that fits your situation

4 Density and size of invasion may determine management strategy Monitor, monitor, monitor! SIZE Small Large Low Monitor infestations; ti may Monitor; grazing practices; need a change in management monitor or manage escape or may pull by hand routes DENSITY High Eradicate spots; continue to monitor closely; promote sustainability of native vegetation tti (change (h in management) Integrated weed management; restoration efforts

5 The Tools of Control Grazing / mowing Herbicides Although costly to approve and apply, the best option to control cheatgrass prior to applying restoration practices (Pellant 1996) Reseeding

6 Mechanical Timed before seed production (early flowering) may reduce seed numbers It is unlikely that seed production will be entirely prevented or stopped (Wicks 1984) Repeated mowing throughout growing season nearly as effective as glyphosate (Ponzetti 1997) Summer mowing may facilitate seed dispersal

7 Mowing Practicality is a question, especially considering i costs May cause significant damage to desirable plants within the matrix of cheatgrass invasion Stephen Enloe photo

8 Livestock Grazing To be effective in reducing cheatgrass you must: Repeat appropriate grazing practices over a multiyear period under different climatic conditions over a diverse landscape. Mealor photo

9 Grazing When cheatgrass comprises the majority of the forage base: Early spring grazing (high intensity / short duration) before seeds are formed Move cattle to allow remnant perennial grass recovery Requires available soil moisture after removing cattle to be effective Avoid overgrazing desirable plants Mealor photo

10 Schmelzer 2009 At least two grazing treatments needed to decrease cheatgrass density (Hulbert 1955) Sandberg bluegrass and crested wheatgrass cover increased in grazed areas after 2 nd fall grazing treatment Preference eee for cheatgrass in fall or winter, e, at least es in drought years (Bishop et al and others) Cattle grazed cheatgrass without loosing body condition, but sample nutritional quality to determine supplementation needs Monitor for weeds, perennial grasses and cheatgrass Mealor photo

11 Proper management of native rangelands to insure that cheatgrass does not increase is the highest priority (Pellant 1996) Cartoon by Laurel Ovitt, NRCS, Montana

12 Herbicides Effective but with some risks Expensive No soil disturbance ALWAYS APPLY ACCORDING TO LABEL!

13 Imazapic (Plateau ) Pre- or post emergent (2-12 oz product / acre) 4-8 oz seems optimum Maintain residual desirable plants No grazing restrictions Can re-seed following application Chemical needs to reach soil surface (litter will inhibit activity) Sagebrush species display high tolerance at label rates

14 Glyphosate (Roundup ) Can be applied at low rates in early spring for suppression Take care to apply when desirable vegetation is dormant to reduce injury Can be used in re-seeding projects 6-12 oz product per acre

15 Imazapic + Glyphosate (Journey ) Provides both pre- and postemergent control Fall is ideal, spring applications can also be used Spring be careful with desirable plants oz product per acre

16 Reseeding Rangeland Where productive rangeland has been taken over by cheatgrass (no native grasses left) Where revegetation ti (drill seeding) is possible Following wildfires Improved/introduced forage grasses that have effectively suppressed cheatgrass (Whitson and Koch 1998): Luna pubescent wheatgrass Hycrest crested wheatgrass Native grasses should be used whenever possible Sodar streambank wheatgrass Calvin Strom photo

17 Assisted Succession Cox and Anderson 2004 Convert site from annual to perennial domination Remove existing vegetation and prepare adequate seedbed for the seeded species This case crested wheatgrass Open niches and allow native seedlings to establish in crested wheatgrass Drilling is effective way to reseed rangelands; rough terrain may need to use broadcast Calvin Strom photo

18 Treatment effectiveness Vary according to: Cheatgrass phenology Pre and post treatment climatic conditions Soil moisture Timing i of treatment t t Land manager choice of treatment Cost of treatment t talso varies