Phalaris Arundinacea (Reed Canarygrass)

Phalaris arundinacea control and riparian restoration within agricultural watercourses in King County, Washington

Ph.D. defense by Lizbeth Seebacher Presentation Outline

• Introduction and Objectives

• Reed canarygrass (RCG) control field project

• Competitive interactions between RCG and Scirpus microcarpus (small fruited bulrush (SFB))

• RCG rhizome carbohydrate reserve experiment

• Conclusions and Recommendations Project Background

• Water Quality • Sediment/Erosion Control • Large Woody Debris • Riparian Vegetation (RCG control) • Fish Biology • Macroinvertebrate communities Phalaris arundinacea (reed canarygrass) • Description – perennial, cool season grass, 2m tall • Spreads predominately by rhizomes • Distributed throughout northern temperate regions • Noxious weed • Hybrid of a native genotype and an introduced cultivar? • Why was it introduced? 1) Cultivation for agronomic purposes began in Sweden in 1749 2) Agronomy, hay and pasture crop, especially on boggy land 3) Convert marshes and wetland to forage fields 4) Erosion control along drainage canals Impacts

• Produces dense monocultures • Out-competes native species, reducing biodiversity

• Obstacle in wetland restoration (Lavergne and Molofsky 2004) • Diminished heterogeneity of microhabitats • Impacts fish utilization and invertebrate assemblages • Alters hydrology; excessive above & below ground biomass Control Methods

• Card board, black plastic and other weed fabrics • Mulch, alone or on top of fabrics • Shading • Mowing, tilling and grazing • Burning • Herbicide • Flooding • Micro and macronutrient manipulation • Competition by natives or other non-indegenous species Dredging and hydroseeding

2 years later Weed fabric with planted willow, red osier dogwood and oceanspray Mowing, cardboard and mulch

Mowing and willow stakes

After just one season

After one year Treatments not successful…

Reed canarygrass (RCG) possesses:

• No known dormancy, high viability rate • Excessive above & below ground biomass • Returns early in the season

• Morphologically plastic (Maurer and Zedler 2002) • Plant architecture • Substantial carbohydrate storage Objectives

The objectives of the riparian vegetation enhancement section of this project include: a) finding a BMP protocol for the effective control of reed canary grass, and b) determining a method for providing native ground cover and woody riparian vegetation that is vigorous, shade producing and provides habitat for insects that constitute prey for salmonids. Presentation Outline

• Introduction and Objectives

• Reed canarygrass (RCG) control field project

• Competitive interactions between RCG and Scirpus microcarpus (small fruited bulrush (SFB))

• RCG rhizome carbohydrate reserve experiment

• Conclusions and Recommendations RCG Control Field Project

King County Agricultural Production Districts (APD’s)

3 sites located within 2 APD’s

Agriculture site Livestock site Natural site Sammamish APD Woodinville, Washington Agriculture Site Sammamish APD Woodinville/Redmond, Washington Livestock Site Snoqualmie APD Natural Site Duvall, Washington Literature Review on RCG control

• Red : Far Red ratio falls dramatically under a canopy

• Levels as low as.05:1 R:FR compared to 1.15:1 R:FR

• Researchers exposed RCG seeds to low red:far-red

ratios, germination decreased by 30% (Lindig-Cisneros and Zedler 2001)

• Also 60% more seedlings under a single species canopy

than under a multi-species canopy (Lindig-Cisneros and Zedler 2001) • Rhizome fragments under heavy shade reduced survival

by 25% and growth by 95% (Maurer and Zedler 2002) Questions

1) Will the following treatments negatively affect the re-growth of reed canarygrass? – RCG barrier densely planted with native species – Hog fuel densely planted with Salix sitchensis – Hog fuel with the RCG barrier

2) Is Scirpus microcarpus an effective competitor with reed canarygrass?

3) How long will the reed canarygrass rhizomes need to be covered with a weed block fabric to deplete the rhizome carbohydrate reserves? Field project methodology and treatment design

2 meters RCG Barrier Hogfuel/willow Hogfuel/RCG Control Barrier 3 m e t e r s

RCG Barrier = burlap fabric, 25 cm of compost, burlap fabric, multi-canopy planting

HF / Willow = 25 cm of hogfuel, burlap fabric, single canopy planting

HF/RCG Barrier = 25 cm hogfuel, RCG barrier RCG Barrier Plot Design at planting

Scirpus microcarpus Symphoricarpus alba

Rubus spectabilis Cornus sericea

Salix sitchensis Rubus parviflorus

Lonicera involucrata Ribes bracteosum RCG Barrier Treatment Plot Design, projected multi-canopy Methods

1) Randomized block design, with 3 treatments (plus control) within 3 blocks (or replicates) chosen randomly at each of the 3 sites. 2) Reed canarygrass mowed, rhizome barrier placed around 2 x 3 meter plots. 3) Three treatments plus control plots applied at each site.

4) The stems of any returning RCG counted and recorded biweekly during the growing season. 5) Data Analysis conducted using a one way ANOVA. Results – Treatment and Site Interaction

Stem count for each treatment at each site

1400.0

1200.0

1000.0

Control 800.0 HFWillow RCG Barrier 600.0 HF RCG Barrier

400.0

200.0 Mean Stem Count per Treatment per Count Stem Mean

0.0 Ag Site Livestock Site Natural Site RCG Control Field Project Results

RCG Returning Stem Count For All Three Sites

1600

1400

1200

1000

800

600 RCG Stem Count RCGStem

400

200

0 Control HF/Willow 1 RCG Barrier HF/ RCG Barrier RCG Returning Stem Count by Site

RCG Final Stem Count 2005 For All Sites

1600.0

1400.0 Agriculture 1200.0 Livestock 1000.0 Natural 800.0

600.0 RCG Stem Stem Count RCG 400.0

200.0

0.0 1 Control RCG Barrier HF/RCG Barrier HF/Willow

Agriculture site – all 3 treatments were significantly different than control , HF /willow #1 Livestock site – all 3 treatments were significantly different than control, HF/willow & HF/RCG barrier most successful Natural site – 2 treatments were significantly different than control, HF/willow & HF/RCG barrier most successful Presentation Outline

• Introduction and Objectives

• Reed canarygrass (RCG) control field project

• Competitive interactions between RCG and Scirpus microcarpus (small fruited bulrush (SFB))

• RCG rhizome carbohydrate reserve experiment

• Conclusions and Recommendations Competitive interactions between RCG and Scirpus microcarpus (small fruited bulrush (SFB))

Agriculture site End of the season 2004

RCG – high competitive effect but low competitive response SFB – high effect and response? Symmetrical? (Keddy et al. 1998)

Livestock site Middle of the season 2005 Questions

2) Is Scirpus microcarpus an effective competitor with reed canarygrass?

3) How long will the reed canarygrass rhizomes need to be covered with a weed block fabric to deplete the rhizome carbohydrate reserves? Competition Study Methods

1) Bare-root RCG and small fruited bulrush (SFB) of similar size # of nodes were collected. Above ground biomass clipped at 10cm, and weighed. 2) Plants of each randomly chosen, planted in 2 gallon pots and placed in the greenhouse at UWBG for 22 weeks. 3) Treatments - competition (RCG vs. SFB), high and low soil moisture, high and low nitrogen 4) Watered and fertilized (NH4 NO3) weekly with Hoagland solution 5) RCG and SFB harvested, washed, determined dry weight of above & below biomass of RCG and sample of SFB 6) Analyzed using a 3 way ANOVA. SM – Soil Moisture N - Nitrogen Low SM Low SM Low N High N RCG vs.RCG Intra-specific competition High SM High SM Low N High N

Low SM Low SM Low N High N RCG vs.SFB Inter-specific competition High SM High SM Low N High N Competitive Interaction Results

RCG Dry Weight

45 40 35 30 25

grams 20 15 10 5 0 R/LSM LN S/LSM LN R/HSM LN S/HSM LN R/LSM HN S/LSM HN R/HSM HN S/HSM HN

Treatment

LSM = Low Soil Moisture R = RCG vs. RCG HSM = High Soil Moisture S = RCG vs. SFB LN = Low Nitrogen HN = High Nitrogen Biomass 20 40 0 R LoSM Mean Below Mean Below Mean Above Low Low Nitrogen R HiSM RCG AboveBelow andGround Biomass S LoSM S HiSM R LoSM R HiSM High High Nitrogen S =RCGvs. SFB R = RCGvs. RCG S LoSM S HiSM Scirpus microcarpus Above and Below Ground Biomass 35

Biomass

0 LSM LN LSM HN HSM LN HSM HN Treatment LSM = Low Soil Moisture HSM = High Soil Moisture Above mean LN = Low Nitrogen Below mean HN = High Nitrogen Presentation Outline

• Introduction and Objectives

• Reed canarygrass (RCG) control field project

• Competitive interactions between RCG and Scirpus microcarpus (small fruited bulrush (SFB))

• RCG rhizome carbohydrate reserve experiment

• Conclusions and Recommendations RCG Rhizome Carbohydrate Reserves

RCG difficult to control due to substantial carbohydrate reserves

The predisposition of the rhizomes to persist with stored energy allow for : • successfully overwinter and produce new tillers early the next season • new tillers to lift and break through standard weed fabrics . • produce new shoots after control treatments Form of Energy Storage

•Reserve Constituent for temperate region grasses: - Sucrose and Fructosans

•Reserve Constituent for tropical grasses: - Sucrose and Starch

•Predominate reserve polysaccharide for RCG:

- Fructosans (Smith 1968) Questions

2) Is Scirpus microcarpus an effective competitor with reed canarygrass?

3) How long will the reed canarygrass rhizomes need to be covered with a weed block fabric to deplete the rhizome carbohydrate reserves? RCG Rhizome Carbohydrate Levels Methodology

1) Samples were taken during mid June during flowering

2) 45 rhizome samples, placed in pot in pot containers

3) Fabric was placed on top to inhibit any photosynthesis

4) 15 samples removed after 3 months , 15 after 6, the last 15 after 9 months

5) Rinsed & dried rhizomes, ground in a Wiley mill for analysis

6) Fructan Assay Kit from Megazyme International, solution measured with the near-infrared spectrophotometer (NIRS)

7) The data was then calculated with the following equation: A x F x 5 x V s 1.1/0.2 x 100/W x 1/1000 x 162/180 RCG Rhizome Samples RCG Rhizome Carbohydrate Levels Results

Percent Rhizome Fructosan Levels versus Time Covered 6.00

5.00

4.00

3.00 % Fructosan

% Fructosan % Linear (% Fructosan) 2.00

1.00

y = -0.2135x + 2.9745 R² = 0.1107 0.00 0 1 2 3 4 5 6 7 8 9 10 Number of Months RCG Rhizome Carbohydrate Levels Results

Average RCG Fructosan Levels After 3, 6, & 9 Months Presentation Outline

• Introduction and Objectives

• Reed canarygrass (RCG) control field project

• Competitive interactions between RCG and Scirpus microcarpus (small fruited bulrush (SFB))

• RCG rhizome carbohydrate reserve experiment

• Conclusions and Recommendations Conclusions

• Two treatments were successful – HF/willow and HF/RCG Barrier

• Hogfuel placement was effective (allelopathic?) HF /RCG Barrier – reduced RCG – 56% • Two species were particularly competitive – Salix sitchensis and Scirpus microcarpus • Willow planted at 0.5 m centers reduced RCG- 64%. Similar reduction rates of RCG

by (Kim, Ewing and Giblin 2006) • SFB, appears to be competitive vs. RCG in high nitrogen & soil moisture treatment • Carbohydrate reserves vary - first 6 months drop after 9 months to less than 1% Problems in the Field * Flood in late 2003 * Another flood in spring 2004 * Beaver attacks * Willow borer (Cryptorhynchus lapathi) Recommendations

1) Till the site if possible, cover the site with opaque, biodegradable material.

2) Use hogfuel on the site if possible.

3) Densely planted willow Recommendations 4) Plant species with competitive abilities - fast growing, early growth, high leaf area index, tall

5) Plant a dense multi-canopy of native vegetation providing habitat diversity and desired invertebrate assemblage (Wipfli 1997, Alan et al. 2003) Acknowledgements Project funded by: King County Water and Land Resources Division My girls - Abigail and Victoria Advisor – Sarah Reichard GSR – Martha Groom Committee members – Kern Ewing, Liz Van Volkenburgh, Sooh Hyung Kim

CUH Students – Caren Crandell, Julie Combs, Rodney Pond, Wendy Descamp, Doug Schmitt, Cheryl Brammer, Alaine Sommagren, Amy Lambert, Lauren Urgenson CUH Faculty and Staff - Wendy Gibble, Carrie Cone, Jon Bakker Landowners – Dave Olney, Roger Calhoon, Tom Quigley