holyoutlaw

A bulleted list! So you know it’s precise! Considering each HMU where we did some work in 2014, starting with the South Plateau:

South Plateau

1. Had been neglected since project dropped by previous forest steward.
2. Neighbor complaints caused us to return to working on it.
3. Water flow appears to be under control. One forest steward has examined it in the rain and observed that most of the water was flowing into a wood chip pile.
4. Personal contact was made with two neighbors of the South Plateau, and a homeowner engaged in a gutting and refurbishing of a house. All contacts were positive.
5. There was one work party in 2014, clearing and planting prep with SPU students.
6. Issues:
• Ivy, holly, blackberry, yellow archangel resurgence.
• Nipplewort, wall lettuce, other annual weeds.
• Water flow seems to be under control, but still needs to be inspected regularly during heavy rain.
• Establishment and after care for already established plants.
• Maintain neighbor relations.
7. 2015 Plans:
• January: Planting work party, 128 plants.
• September: Clearing and prep for planting with SPU students.
• Forest stewards will continue to work approximately one Monday a month, to maintain cleared areas and prevent reinfestation. We will also attempt to spread seeds of native plants as appropriate, particularly Dicentra Formosa (Pacific bleeding heart).

Central Valley:

1. Began 2014 with clearing about 800 square feet, down the trail from Knotweed Hill. The clearing happened on both sides of the trail, so it was in both the Central Valley and on the base of the 91st St. Slope.
2. The area was neglected during the summer months in favor of after care for plants in drier areas of the park – along the North Slope side of the main trail and along the 24th Ave. rim.
3. A three person crew worked on the area during the August work party.
4. This area will be planted in the November work party. There will be enough people there to do some clean up first.
5. Extensive planting happened in the seeps at the eastern edge of the Central Valley during the October work party.
6. 2015 plans: Forest stewards and work parties will monitor cleared areas to prevent invasive resurgence and provide after care as/if necessary.

91st St. Slope:

1. In addition to the clearing mentioned above, a thicket of laurel was limbed by forest stewards early in the summer.
2. This thicket was given both E-Z-Ject and cut and paint treatments to kill the laurel.
3. Forest stewards will monitor this laurel thicket.

Knotweed Hill (Knotweed Hill is located at the border of the North Slope and the 91st St. Slope HMUs.)

1. Knotweed Hill was treated for knotweed in the summer of 2014.
2. There was some watering of the upland plants in the summer, but it has received no other attention.
3. It needs to be monitored for invasive resurgence and any after care.

Headwaters Bowl (“HWB”):

1. The narrow, western section of the HWB received about half the plants from the October work party. Some plants were put into bowl section as well.
2. The area between the north side of the streambank and the main trail received a lot of clearing in 2013 from EarthCorps and Parks Dept. contract crew. These cleared areas need to be regularly inspected to prevent resurgence and to provide after care for plants installed in 2013.
3. An area of the HWB that has received little attention so far was transected by two forest stewards (Luke and Drexie) in October. We started at the Two Cedars area (about 150 feet down the main trail) and crossed the HWB just west of a line of old Alnus rubra (red alder).
   • North of the stream, we saw a large number of small Vaccinium parvifolium (red huckleberry). It was unclear whether they were planted or volunteers.
   • Immediately south of the stream crossing the soil was very wet and marshy. There were many large Lysichiton americanum (skunk cabbage) leaves dying back. There was also evidence of Equisetum arvense (horsetail) from earlier in the season.
   • Further south of the stream crossing, the ground rose slightly and was dryer. At that point, the Rubus spectabilis (salmonberry) became very thick.
   • There was some Polystichum munitum (sword fern) and Athyrium filix femina (lady fern), but ground cover in general was relatively sparse.
   • There was a thicket of Ribes bracteosum (stink currant) at the border of the wet and dry areas.
   • At the base of the south slope we stopped to write down what we’d seen so far. In addition to the already mentioned plants, there were:
   • Emergent (that is, taller than the shrub layer) Acer macrophyllum (big leaf maple) and Alnus rubra (red alder).
   • Sambucus racemosa ssp. pubens (red elderberry) thicket.
   • Sorbus aucuparia, European ash.
   • An apparently dead Populus balsamifera (cottonwood) stake from 2012.
   • Going up the south slope to the houses, we saw:
   • Sword fern as dominant groundcover.
   • Occasional salmonberry, but fairly isolated and lower on the slope. Otherwise, no shrub layer to speak of.
   • Big leaf maple trees dominant towards the middle of the slope, with conifers along the rim (we weren’t able to identify the conifers from that distance).
   • We continued east along the base of the south slope towards the 24th Ave. Slope.
   • Outside of the tree cover, the ivy was very dense, bushy, and had many many seed pods.
   • There were a couple small Thuja plicata (Western red-cedar) that Tad and Luke had liberated from salmonberry in 2012; Luke and Drexie liberated them again.
   • The base of the 24th Ave. rim was dominated by Hedera helix (English ivy), with Urtica dioica (stinging nettle) growing up between it. There was no shrub layer and no regenerating trees.
   • The culvert that empties into the park from the corner of the 24th Ave. slope and the south slope has gouged a deep channel. There is a lot of construction rubble in the channel, but also some large garbage (garbage cans, tires, etc.) that should be removed. This is on private property, but if at all possible it should get treated with some rip rap. The channel is still carved farther down, and at the base of the slope and in the flat area it can receive fascines or woody debris.
4. For 2015, we will work with the Parks Department to determine what can be the scope of volunteer work in the private property areas of the HWB, and then contact the neighbors to get permission for that work.

Mirrored from Nature Intrudes. Please comment over there.

This post gives an overview of the wetlands in North Beach Park and looks specifically at the Headwaters Bowl. The next post looks at the Central Valley. The third post in this series will discuss the stewardship grant from the Washington Native Plant Society to the Friends of North Beach Park. The 92nd St. Wetlands will be discussed later, with Fletcher’s Slope.

Approximately 4.5 acres of North Beach Park are designated as wetlands. These wetlands are formed by broad, horizontal, groundwater seeps emerging from the sides of the ravine. These join to form the stream that leaves the park. The seeps are perennial, and have lasted through record droughts.

The wetlands have many areas that are permanently saturated, and walking in them quickly disrupts whatever soil structure there is. Other places are more stable.

Figure 1: Wetlands in North Beach Park. Thick green lines indicate park boundaries. Light grey lines indicate HMU boundaries. The filled blue area is the wetlands. Wetland delineation by Doug Gresham of Gresham Environmental (2012). (Map by the author.)

Doug Gresham, of Gresham Environmental, delineated and typed the wetlands in 2012:

North Beach has both Palustrine (freshwater) and Riverine (riparian) wetlands. The plant community is scrub/shrub and the water regime ranges from saturated soil to permanently flowing streams. The groundwater seep wetlands would be called palustrine, scrub/shrub, saturated (PSSc). The stream would be called riverine, upper perennial, unconsolidated shore, permanently flooded (R3USh).

The hydrogeomorphic classification system groups wetlands based on functions and values. … The groundwater seep wetlands would be called slope wetlands and the stream is a riverine wetland.

The Washington Department of Ecology classifies wetlands into four categories based on their hydrogeomorphic class and score from a rating form. King County and City of Seattle governments rely on this classification system to create their critical area ordinances. The highest quality wetlands (Category I) are rare, while low quality wetlands (Category IV) are somewhat rare also. Most wetlands fall into the Category II and III level depending on how well they function. North Beach would probably be Category III because it is degraded. (Gresham, 2014)

In October 2005, the US Fish and Wildlife Service did a fish habitat survey of streams in the Seattle area. “Unnamed PS08 West Fork” is the stream that flows through North Beach Park (see figure 2, below). At their sample site (which would now be in the Headwaters Bowl HMU), they found the stream to have a mean wetted width of 1 meter (m); a mean depth of 0.03m with a max depth of 0.1m; and to consist of 100% riffles with no pools or glides. The substrate was 100% silt/sand. They did not catch any fish in the sample site. (Tabor 2010)

Figure 2: Location of US Fish and Wildlife 2005 survey sample in North Beach Park.

The Central Valley, at 1.97 acres, and the Headwaters Bowl, at 1.39 acres, are the two largest HMUs in North Beach Park. For restoration purposes, we have split them into four subareas each. The subdivision is based on who can do the work: all volunteers, experienced forest stewards, Parks Department Natural Area Crew, or privately-contracted restoration crew.

Headwaters’ Bowl

Description

Figure 3: Headwaters Bowl. The Headwaters Bowl is the area in light green (planting) and blue (establishment). The blue line is the stream. North is to the top. (Source: GSP Reference Map on ArcGIS.com.)

The Headwaters Bowl (“HWB”) is the easternmost HMU of North Beach Park.

The northern boundary is the main trail of the park, the eastern boundary is 24th Ave. NW, the southern boundary is property lines and the South Slope, and the western boundary is the stream crossing and the social trail between the Headwaters Bowl and the Central Valley.

The property lines cut the bottom of the bowl and the 24th Ave. slope in half, and remove the southern slope entirely. Parks Department volunteers and Natural Area Crew are not allowed to work on private property. This complicates restoration of the HWB as discussed below in “Invasive Removal and Restoration Plan.”

At the start of restoration, nearly half the trees in the HWB had severe Hedera helix (ivy) infestations which frequently reached into the canopy. There were large pockets of ivy monoculture on the ground.

The percent cover for trees was approximately 70% deciduous, with Alnus rubra in the wetlands and Acer macrophyllum on the dryer slopes and uplands. There was 5-10% conifer cover, exclusively Thuja plicata (Western red-cedar). The remaining 15-20% cover was open gaps, either over areas too wet to sustain trees or where A. rubra had fallen. The percent cover of the regenerative trees (tall enough to be above the shrub layer) was less than 5% for deciduous and less than 1% for coniferous trees.

Ilex aquifolium (English holly) and Prunus laurocerasus (English laurel) formed occasional dense thickets. Most of these have been removed, either by uprooting or cutting and painting with herbicide.

The HWB native plant communities at the start of restoration were very similar to the Alnus rubra/Rubus spectabilis (Red alder/Salmonberry; ALRU/RUSP) and Alnus rubra/Lysichitum americanum (Red alder/skunk cabbage; ALRU/LYAM) communities described by Kunze (1994). The differences were largely that the communities in the park lacked herbaceous diversity compared to the reference communities.

These communities are dominated by an Alnus rubra (red alder) canopy, with either Rubus spectabilis (salmonberry) or Lysichitum americanum (skunk cabbage) as the undercanopy. Kunze describes the ALRU/LYAM community as being wetter than ALRU/RUSP, and that is the case in NBP. (Plant communities are discussed in more detail in “Target Forest Types”).

There is a canopy gap over the most saturated, eastern part of the HWB. This area is dominated by skunk cabbage and horsetail, with some Salix sitchensis (Sitka willow) shrub. The invasive plants here include Rubus armeniacus (blackberry) and Calystegia sepium (bindweed). Numerous A. rubra lean over this part of the HWB from the slopes. As they die and fall, the gap will enlarge. This will also increase the amount of coarse woody debris in the wetland and the number of rootballs on the slope walls.

Progressing to the west, the topography and soils become more complicated. Some areas are more stable, and some are seeps that have reached down to the gleyed soils. As the ravine narrows, Acer macrophyllum (Big leaf maple) on the south slope add their shade.

The majority of the HWB is in phase two, “planting,” of restoration. A section of Subarea C is considered to be in “establishment,” phase 3. For a discussion of the phases, please see “Monitoring Protocols and Success Metrics.”

Water Flow

Groundwater emerges from several places at the base of the 24th Ave. slope. One of these areas has a number of displaced conduits. During heavy rainfall, water emerges from a conduit in the southeastern corner of the hillside.

Through the rest of the Headwaters Bowl, the water emerges as seeps or occasionally channels from the south slope of the ravine. In many places the seeps have carried away most of the soils.

These seeps join the stream, which runs along the northern edge of the headwaters bowl. Water flow in North Beach Park, in general, needs a lot more research and observation.

Vegetation

As discussed above, the plant communities in the HWB are currently a mixture of ALRU/LYAM (to the east) and ALRU/RUSP (to the west).

The reference ecosystem for the Headwaters Bowl is “riparian forest and shrubland.” The target forest type is ALRU/RUSP/CAOB-LYAM (Red alder/salmonberry/slough sedge – skunk cabbage) as described by Chappell (2006).

There has been one circular, 1/10th-acre, monitoring plot established in the Headwaters Bowl. Baseline monitoring was taken in August 2012, with a follow-up in August 2013. See “Green City Monitoring Protocol” in “Monitoring” for a discussion of this protocol. This monitoring plot was established in the middle of the most saturated section of the Headwaters Bowl.
The following table presents the vegetation findings from the 2012 and the 2013 monitoring and the change. Native plants listed as 0 in the “2012 % Cover” column were planted in autumn 2012. Percent cover was determined by consensus of the people doing the monitoring plot, and is reported in broad categories to enable the data to be consistent across the city.

Table 1: Forest Monitoring Plot report, Headwaters Bowl.

Only one invasive plant decreased in cover, Rubus armeniacus (blackberry). This was the plant we most vigorously removed. The native plants that went from 0 to <1% cover had been planted in the fall of 2012. Lysichiton americanum (Skunk cabbage) increased from the seed bank. Calystegia sepium increased noticeably all over the park in 2013.

Although this gives a good representation of the most-saturated areas of the HWB, it does not give a good representation of the HWB as a whole. A couple dozen feet to the west of this monitoring plot, there is a stand of A. rubra that indicates dryer conditions. This allows greater shrub establishment.

Invasive Removal and Restoration Plan

I have divided the Headwaters Bowl into four subareas, based on who can perform the needed restoration work (see below).

Figure 4: Headwaters Bowl and subareas. A: All volunteers can work here. B: Forest stewards and experienced volunteers. C: Parks District Natural Area Crew (slope). D: Privately contracted crew (slope, private property).

Subarea A

Subarea A is between the main trail and the stream bank. It is relatively flat and dry, making it accessible to all volunteers. It measures approximately 16,500 square feet (all areas calculated using the measurement tool on GSP Reference Map on Arcgis.com).

Subarea A has received the most attention of any area in the park, beginning with the very first work party. As a consequence of it receiving such early attention, no good record was kept of its pre-restoration state; the notes below are reconstructed from memory.

There were few areas of Hedera helix (English ivy) monocultures in Subarea A. There were some areas of Ilex aquifolium (English holly) and Prunus laurocerasus (Cherry laurel) dominance. The ivy has been removed by hand. The holly was removed by uprooting. The laurel was removed by cutting and painting.

In late summer and fall of 2013, several EarthCorps work parties concentrated on invasive removal in this section.
Plants have been installed and invasives removed every year, and it is now in an establishment phase.

Suggested tasks for Subarea A:

• Explore the western end in further detail.
• Continue monitoring the planted area for native plant establishment and invasive resurgence.
• Track mature Alnus rubra and naturally regenerating Thuja plicata and Acer macrophyllum.
• Start a new generation of deciduous trees.
• Add to the herbaceous diversity annually.
• In 2021 (ten years after restoration began), add a new generation of conifer trees.

Subarea B

Subarea B is the center of the bowl, and because of the saturation and fragile soil structure is more difficult to work in than Subarea A. This makes it accessible to small groups of experienced forest stewards only. It measures about 45,000 square feet.

The widest part, to the right in the image, is permanently saturated. It receives invasive removal in the late summer, when it’s relatively dry. It has received plantings of graminoids and shrubs. The eastern edge of Subarea B is the location of the circle monitoring plot discussed above. The part of Subarea B not in park property needs further exploration.

The narrower part has many seeps, separated by tongues of soil held in place by Carex obnupta (slough sedge) and/or Rubus spectabilis (salmonberry). In the spring and summer, these seeps contain forbs such as Oenanthe sarmentosa (Water parsley). However, there is no woody vegetation to hold the seeps during winter.

Some Picea sitchensis (Sitka spruce) and Thuja plicata (Western red-cedar) have been planted in the seeps.

In June 2014, Friends of North Beach Park received a $500 stewardship grant from the Puget Sound Chapter for the purchase of wetland plants. These plants will be installed along the streambank and in the seeps of the western (left) edge of Subarea B of the Headwaters Bowl, and across to Subarea B of the Central Valley. This grant is discussed in more detail in “Stewardship Grant.”

Suggested tasks for Subarea B, in the lobed area to the east:

• Continue removing blackberry.
• Establish shrubs where possible, graminoids elsewhere.
• Explore the base of the slope and the bowl during a rain event.

Suggested tasks for Subarea B, in the narrow part to the west:

• Implement the WNPS Stewardship Grant in autumn of 2014.
• Continue removing invasives as necessary.
• Monitor seeps for erosion.
• Establish obligate wetland plants in the seeps.

Subarea C

Subarea C measures roughly 10,200 square feet. It is the slope along 24th Ave NW and around the entrance to the park along the main trail. Because it is a greater than 40% grade, only Parks Department Natural Area crew or contract crew can work on it. Volunteers have worked on it in the past, however.

In 2011, trees along the rim and slope received survival rings and there was some clearing of the slope.

In 2012 and 2013, the rim received some planting by the Friends of North Beach Park. During the summer months, these plants are watered and weeded. These plants include shrubs such as Aruncus dioicus var. acuminatus (Goatsbeard), Rosa nootkana (Nootka rose) and trees such as Pseudotsuga menziesii (Douglas-fir) and Pinus contorta var. contorta (Shore pine).

In 2013, the slope was partially cleared by a group of EarthCorps volunteers. The clearing was completed by a contract crew, who also put down jute rolls and planted in the fall.

Figure 5: Steep slope jute erosion control by contract crew.

The remainder of the clearing, following the curve of the slope along 24th Ave. and ending at the property line, will happen in 2014 or 2015.

Volunteers and forest stewards can maintain the plants at the rim and the base, but further tasks along the slope in this subarea will be executed by the Parks Department.

Subarea D

Subarea D measures approximately 13,800 square feet. It has not been explored in any great depth. Some trees were given survival rings during the first work parties in 2011. One house appears to have impermeable erosion control fabric, held down by sandbags, on the slope beneath it.

Subarea D is entirely private property on a very steep slope. The houses were built between 1959 and 1963 (King County Parcel Viewer), long before there was any movement to make the ravine a park or any attempt to preserve urban wetlands. The property lines, as shown below, extend into the bowl of the park, which allows the owners to have addresses on 24th Ave. This group of houses, as a whole, is called Olympic Terrace.

Figure 6: Property lines and park boundaries of HWB. The green area is North Beach Park. The red lines are parcel boundaries for private property. (Source: Seattle Department of Public Development DPDGIS).

Due to the steepness of the slope, and the fact that it is private property, Subarea D can only be worked on by a privately contracted crew.

Working in Subarea D depends on securing the cooperation of the homeowners. We plan to contact them in autumn 2014 or early 2015 by doorbelling or leaving door hangers. If this contact is successful, we will

• Explore the area along the bowl and the base of the slope to get an estimate of its invasiveness and what work needs to be done.
• Design restoration plans that range from one-year brute force through multi-year phased work (which plan gets executed would depend on the size and time span of the grant).
• Work with neighbors to write a grant that can be applied to private property (with King Conservation District or other organization).
• Restore Subarea D per grant.

The large contingencies in this plan are (a) successfully contacting and securing the cooperation of the neighbors and (b) obtaining the very competitive King Conservation District grants.

The constraints against working in Subarea D would make it low priority if it were in another section of the park. However, its proximity to the headwaters increases its importance.

Mirrored from Nature Intrudes. Please comment over there.

Last Saturday (7/13) was another EarthCorps event at North Beach Park. This one featured ivy removal on a slope at the Headwaters Bowl. The previous work party had about 50 people signed up, but the summer work parties have much smaller attendance. This time, we had about 16 people altogether. This was exactly enough people for the spaces we were working in and the work we had to do.

Tools ready for use

When EarthCorps arrives on site, they set up a couple shade structures and tables, and they set out the tools expected for the day. (They also provide a porta potty and bring a big bag of energy bars. All helpful!)

Now we have a few “before” pictures:

Holly Thicket

About five people (altogether) worked throughout the day on pulling up this holly thicket.

Ivy Platform

Friends of North Beach Park built this ivy platform in June; we thought that it would last a couple work parties. Not only did one EarthCorps work party completely fill it, but they had to build two more platforms, one for the holly and one for more ivy.

Headwaters Bowl Slope

This is a partial view of the ivy removal work area. The slope was pretty much an ivy monoculture.

Morning Plan

Ethan (from EarthCorps) explains the morning plan.

Platform filled in

After about an hour of work, the platform was almost filled. Masha (from EarthCorps) in foreground.

Gigantic Holly Root

Tad holds up a holly root. It’s that large brown mass in front of him.

Slope Crew

The morning slope crew poses for a quick snapshot. You can begin to see how much they’ve cleared already, about about 90 minutes of work.

Slope at Lunch Break

The bare slope in this picture was covered in ivy just a short while before. The ivy still visible is just scraps.

For the afternoon, we basically split into three crews. One worked on putting burlap down on the exposed slope, another worked on more ivy removal, and the third returned to the holly thicket.

Afternoon Removal

The afternoon removal crew worked in an area that had ivy and sword fern mixed.

Mulching the Slope

Even though it’s burlap, it’s still considered mulch. We used up the burlap that was on site, and for the next work party (in September) we will finish covering the slope with burlap and then add some wood chips on top. This will both suppress ivy resurgence and keep the soil moist.

And now a few “after” pictures, taken after the work party was over.

The slope with burlap

Since we only had a little burlap, we only did one layer. On other slopes, we’ve done two layers. Even so, there’s enough overlap that there are some areas with two or three layers of burlap. The stakes hold the burlap in place and provide footing as you work up the slope. Starting at the bottom allows you to overlay the burlap like roof shingles. Overall, this will slow down (if not stop) the water to allow it to soak in, rather than just run off.

Holly Thicket After

This is the holly thicket, much reduced. Although there is still a lot to do, and we’ll have to keep an eye on this site for a while. Holly can resprout from even tiny root fragments. But they’ll be easy to pull.

Afternoon Debriefing

Masha leads the afternoon debriefing, a quick survey and general feedback.

Trash Haul

And last but not least, the trash haul this time: Three tires, a couple coolers, torn-up mattress, and three contractor bags of bottles’n'cans. Not spectacular, but about average.

Also in the park that day was a film crew for the 48 Hour Film Project, Team Bad Elephant. I didn’t get to see what they were doing, but it was fun to have another group in the park doing something completely unrelated to what we were.

The remaining EarthCorps work parties are on these days. All events meet at the main entrance to the park, 90th St. and 24th Ave NW., and all events are from 10 a.m. to 2 p.m. Go here to sign up. As of this writing, they’re not posted yet.

Saturday, September 14 (more removal, mulching of cleared areas)
Wednesday, October 23 (planting!)
Saturday, November 9 (planting!)

Mirrored from Nature Intrudes. Please comment over there.