LA-39 Year 5 Reggio Monitoring Report Final (2)

Pezold, Blaise and Strickland, Ashton -Crescent Soil Water Conservation District

LA-39 YEAR 5 REGGIO FIELD TRIAL FINAL REPORT 2015

LA-39 Year 5 Reggio Field Trial Final Report

Background

The NRCS project team visited the Reggio area on April 1, 2015. The area was found to be badly

deteriorated. While the team agreed that there may be some potential to improve the area with

vegetative plantings, there are some significant challenges -- very soft organic soils, tidal

influence, large open water fetch, nutria herbivory, and some areas where access is impeded by

cypress stumps. Because of the great need for restoration, but difficult conditions, the project

team designed a vegetative field trial to install 1,000 Schoenoplectus californicus (California

bulrush) plants. A cooperative agreement between Crescent Soil and Water Conservation

District and NRCS was executed on June 9, 2015. A Notice of Grant and Agreement Award was

also executed on June 9, 2015.

Prescribed Planting Layout

Two types of plantings were to be installed: single row and paired double row plantings. For

each of the single row locations, 100 plants would be installed on five-foot (5’) centers to the

extent possible. For each pair double row plantings, 200 plants shall be installed. The paired

rows were to be five to ten feet (5’-10’) apart and parallel to the planting centerlines with plants

to be installed on five-foot (5’) centers to the extent possible. The cooperative agreement

includes a plan map with the planned locations of each row centerline.

At each of the seven (7) sites, seven (7) of the plants (49 total) were to be protected by a nutria

excluder device (NED), the design of which would be agreed upon by SWCD and NRCS.

Plant Installation

NRCS and SWCD travelled to the project site on June 22. Based on site conditions (primarily

water depth and surrounding aquatic vegetation) and accessibility, NRCS and SWCD jointly

adjusted the planting centerlines, marking each with 10-foot pvc poles and recording coordinates.

Plants were supplied to Crescent SWCD by T-Beb’s Wetland Nursery of Montegut, LA. The

plants were installed on June 23, 24, and 25. Planting was very challenging due to soft and fluid

organic soils. While all sites had fluid soils, the double row planting sites (located on un-

vegetated mudflats and away from the emergent shorelines) were so fluid that the plants were

generally “suspended” 6 to 12 inches deep into the “ooze” with very little soil structure to

support the plants. This condition was one of the main reasons why a field trial approach was

being used in this badly deteriorated area. Plant survival was expected to be very low.

The final location of all plants are illustrated in a set of as-built plans prepared by NRCS dated

July 8, 2015 (Attachment A), reflecting the locations marked on June 22 with the following

minor adjustments. 1) On one of the single row planting sites, the western end pole (Point 1000)

was re-set after planting was complete to mark the as-built end of the row. 2) The double row

identified by points 1010-1011 extends to the southeast approximately 60 feet past point 1010. 3)

Twelve excess plants were installed in the vicinity of point 1016. 4) Additional excess plants

(approximately 60) were installed on a double row, identified by points 1017-1018, with plants

on 10-foot centers.

At each of the seven (7) original sites, a NED was installed on seven (7) plants. One (1) NED

was installed in the group of excess plants installed in the vicinity of point 1016. No NEDs were

installed among the excess plants on the double row identified by points 1017-1018.

A final inspection was conducted by NRCS on June 25, 2015, and the work was found to be

completed in accordance with requirements.

Monitoring Results Crescent SWCD monitored plant survival / mortality and vegetative expansion at 30, 60, 90 and

120 days post plant installation. Data sheets for each monitoring event are provided in

Attachment B). The survival of the plants decreased each month to due environmental factors

such as herbivory and the accumulation of aquatic vegetation.

The plants on the mud flats (1008-1009, 1010-1011, 1012-1013, 1016, 1017-1018) were easily

accessible to nutria and therefore suffered the most mortality, however, the plants that were

further into deeper, open water had a higher survival rate than those in shallow areas. See Graph

1. For all mudflats combined at 120 days post installation, overall plant survival was 12%;

survival for plants without NED’s was 10%; and survival for plants with NED’s was 100%.

The plants on the emergent shorelines (1000-1001, 1002-1003, 1004-1005, 1006-1015, 1007-

1014) suffered little to no herbivory, and had high survival in the first half of the monitoring

period. A change in wind direction pushed a large amount of aquatic vegetation against the

shoreline, causing large mats to accumulate and cover the California bulrush. It is likely that the

photosynthetic process was inhibited for an extended period of time, causing high mortality

rates. See Graph 2. For all shoreline plantings combined at 120 days post installation, overall

plant survival was 17%; survival for plants without NED’s was 12%; and survival for plants with

NED’s was 95%

Attachment C provides selected photographs, in a presentation format, that illustrate the two

primary causes of mortality: herbivory and aquatic vegetation.

Graph 1. Plant survival at 30, 60, 90 and 120 days post plant installation for the mud flat

plantings.

0

50

100

150

200

250

June July August September October

PLA

NT

SUR

VIV

AL

MONITORING MONTHS

Mud Flat Plantings1008-1009 1010-1011 1012-1013 1016 1017-1018

Graph 2. Plant survival at 30, 60, 90 and 120 days post plant installation for the shoreline

plantings.

Future Plantings

While survival at 120 days post construction was low, there remains a great need for restoration

all around the vicinity of the LA-39 Year 5 Reggio Field Trial site. As part of the State of

Louisiana’s Vegetative Planting Program, Crescent SWCD has a proposed Schoenoplectus

californicus planting for the Reggio area in spring 2016. This planting will attempt to address

the primary causes of mortality by placing plants at slightly greater depths, away from emergent

shorelines to discourage herbivory and prevent large mats of aquatic vegetation from

accumulating on top of the plants.

Suggestions

Because the cooperative agreement between Crescent SWCD and NRCS expires on December

31, 2015, Crescent SWCD suggests that NRCS return to the project site next growing season to

determine survivability, particularly whether the NEDs continue to be effective and whether

some of the plants may have persisted despite the above described impacts of the aquatic

vegetation.

0

20

40

60

80

100

120

June July August September October

PLA

NT

SUR

VIV

AL

MONITORING MONTHS

Shoreline Plantings1000-1001 1002-1003 1004-1005 1006-1014

Attachment A.

Attachment B.

7/29/2015 30 days post planting

Blaise Pezoid Ashton Strickland

Outboard Pirogue

1000-1001 Shoreline 100 85 85 83% Good 7 Minor Nutria

1002-1003 Shoreline 100 99 100 99% Excellent 6 (1 mangled) None Some tips of Bulrush have slight insect damage

1004-1005 Shoreline 100 62 62 53% Poor 6 (1 mangled) Minor Nutria Poor planting technique led to high mortality

1006-1014 Shoreline 100 96 96 92% Excellent 7 Minor Nutria Some yellowing of leaves due to algae being deposited on plants by high tides.

1008-1009 Double Row 200 148 148 72% Good 7 None Some yellowing and broken stems, not significant.

1010-1011 Double Row 200 61 61 31% Good 7 Extreme, every plant not covered with a NED at higher elevation is gone.Largest mortality is at slightly higher elevation, large amount of wading fowl are present

in that area.

1012-1013 Double Row 200 82 82 39% Fair Significant Nutria Damage

1016Excess Plants-

Cluster12 7 7 58% Good 1 Minor Nutria

1017-1018

Excess Plants-

Double Row (10'

ctrs)

65 innaccessable 0 N/A N/A N/A N/A N/A

LA-39 Year 5 Reggio Field TrialMonitoring Date:

Participants:

Boat Type(s):

Occular Estimate or

complete count

Approx # Plants

InstalledType

Location

Points

# or % Plants

Present

# or % Plants

Surviving

* Condition categories: Excellent = vigorous w/ new growth evident; Good = appears healthy but no new growth yet; Fair = alive but evidence of some stress (yellowing, broken stems, etc); Poor = alive but damaged or definite evidence of stress

** Grazing categories: None; Minor = a few stems clipped; Significant = ~50-75% of stems clipped; Extreme = Most or all stems clipped &/or plant dug up.

OTHER OBSERVATIONS /

COMMENTS

# or % NEDs Present

& Intact

Condition of

Surviving Plants * Evidence of Grazing on Unprotected Plants (Y/N; describe) ** Other Observations / Comments



Outboard Pirogue

1000-1001 Shoreline 100 85 85 85% Good 7 Minor Nutria SAV has obstructed photosynthesis. SAV was removed from plants.

1002-1003 Shoreline 100 67 67 67% Fair 6 (1 mangled) Minor Nutria SAV has obstructed photosynthesis. SAV was removed from plants.

1004-1005 Shoreline 100 41 41 31% Poor 6 (1 mangled) Minor NutriaSAV has obstructed photosynthesis. SAV was removed from plants. Poor planting technique

combined with SAV led to high mortality.

1006-1014 Shoreline 100 93 93 87% Fair 7 Minor Nutria SAV has obstructed photosynthesis. SAV was removed from plants.

1008-1009 Double Row 200 83 83 39% Excellent 7 NoneFirst 30 ft. of plants in rows have been washed out of the mud flat. A total of 5 plants observed

floating in 2 ft. deep water.

1010-1011 Double Row 200 37 38 19% Excellent 7 Extreme, every plant not covered with a NED at higher elevation is gone. Minor amount of mortality due to SAV obstructing photosynthesis.

1012-1013 Double Row 200 21 21 10% Excellent 7 Significant Nutria Damage, most unprotected plants are nonexistant. The plants toward the Eastern end (Way point 1013) are in greater condition.

1016Excess Plants-

Cluster12 2 2 16% Excellent 1 Extreme, every plant not covered with a NED at higher elevation is gone. Nutria or unstable substrate have killed a majority of the plants.

1017-1018

Excess Plants-

Double Row (10'

ctrs)

65 0 0 0 Poor 0 Extreme, no plants exist. The row no longer exists.


Participants:

Boat Type(s):

Location

Points Type

Approx # Plants

Installed

Occular Estimate or

complete count

# or % Plants

Present

# or % Plants

Surviving



Condition of

Surviving Plants *

# or % NEDs Present

& Intact Evidence of Grazing on Unprotected Plants (Y/N; describe) ** Other Observations / Comments


COMMENTS



Outboard Pirogue

1000-1001 Shoreline 100 61 61 61% Excellent 7 Minor Nutria Evidence of mortality due to SAV, Survivors in great condition

1002-1003 Shoreline 100 42 42 42% Fair 5 Minor Nutria 50% mortality due to SAV

1004-1005 Shoreline 100 22 22 19% Poor 6 None High SAV mortality

1006-1014 Shoreline 100 63 63 25% Fair 7 None SAV has decimated population, some plants have rebounded

1008-1009 Double Row 200 61 61 30.50% Good 7 Yes, Significant The plants that are present have exhibited lateral growth

1010-1011 Double Row 200 22 22 11% Good 5 Yes, Significant The plants that are present have exhibited lateral growth

1012-1013 Double Row 200 22 22 11% Fair 7 Yes, Significant Evidence of mortality due to SAV

1016Excess Plants-

Cluster12 1 1 0.08% Good 1 Yes, Extreme

1017-1018

Excess Plants-

Double Row (10'

ctrs)

65 0 0 0% Poor 0 Yes, extreme



Condition of

Surviving Plants *

# or % NEDs Present

& Intact

Evidence of Grazing on Unprotected

Plants (Y/N; describe) ** Other Observations / Comments


COMMENTS


Participants:

Boat Type(s):

Location

Points Type

Approx # Plants

Installed

Occular Estimate or

complete count

# or % Plants

Present

# or % Plants

Surviving



Outboard Pirogue

1000-1001 Shoreline 100 10 10 6%? Poor 2 Yes, Minor, 1 plant on bankline with roots exposed by Nutria Large amount of SAV covering plants, estimates are most likely incorrect

1002-1003 Shoreline 100 31 31 31% Good 5 No, Minor Wind direction has cleared SAV from plants

1004-1005 Shoreline 100 7 7 5% Fair 5 No, Minor Large amounts of SAV present

1006-1014 Shoreline 100 38 38 26% Poor 7 No, Minor High mortality due to SAV

1008-1009 Double Row 200 62 62 27% Excellent 7 No, Minor Tide is + 3.5 in height and 3.7 ppt due to Tropical storm Patricia

1010-1011 Double Row 200 20 20 10% Good 5 No, Minor Tide is + 3.5 in height and 3.7 ppt due to Tropical storm Patricia

1012-1013 Double Row 200 22 22 11% Good 4 No, Minor Tide is + 3.5 in height and 3.7 ppt due to Tropical storm Patricia

1016Excess Plants-

Cluster12 0 0 0% Poor

1017-1018

Excess Plants-

Double Row (10'

ctrs)

65 0 0 0% Poor


COMMENTS



Condition of

Surviving Plants *

# or % NEDs Present

& Intact Evidence of Grazing on Unprotected Plants (Y/N; describe) ** Other Observations / Comments


Participants:

Boat Type(s):

Location

Points Type

Approx # Plants

Installed

Occular Estimate or

complete count

# or % Plants

Present

# or % Plants

Surviving

Attachment C.

LA-39 Year 5 ReggioField Trial 2015

InstallationAll segments were planted with California bulrush (Schoenoplectus californicus) on five foot spacing and 50 Nutria (Coypus myocastor) exclusion devices (NEDs) were installed.

Two major detrimental factors:

Herbivory and Aquatic Vegetation

HerbivoryCalifornia bulrush plant with roots exposed from nutria herbivory.

HerbivoryThe plants in the foreground are in greater depths, the plants in the background are in shallow depths. In shallow depths only the plants with NEDs remained at 120 days post plant installation. The greater depths seemed to limit herbivory.

HerbivoryIn segment 1012-1013 only plants protected by a NED survived.

Submerged Aquatic Vegetation (SAV) and Floating Aquatic Vegetation (FAV)Wind blown SAV- Myriophyllum aquaticum, Ceratophyllum demersum and FAV- Lemna minor smothering segment 1010-1011.

SAV and FAVCalifornia bulrush in SAV and FAV struggling to photosynthesize.

SAV and FAVCalifornia bulrush with SAV draped over the NED.

SAV and FAVCalifornia bulrush surviving in spite of SAV and FAV

Documents

LA-39 Year 5 Reggio Monitoring Report Final (2)