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Let’s start with the array of plant communities visible from this spot. Our goal is to understand not only what species grow here but why. We also want to know how they are changing over time. On this diverse and dynamic site, communities respond primarily to soil moisture and surface age:
1) Mowed lawn, well drained; 2) Tall herbs including Angelica (A. genuflexa, white blossoms) on intermediate drainage sloping to the stream terrace; 3) Former tidal slough, now a sluggish freshwater creek choked with invasive marsh forget-me-not; 4) Mixed grass/sedge community indicates slowly drained soils; 5) Willows grow on slightly drier but still-damp soils; 6) “Uplift spruces” frame most of Amalga meadows, backed by: 7) old growth on upland slopes.
Simply by noticing this pattern of communities, we can start to understand some of the geological processes and human influences fundamental to an understanding of Amalga Meadows.
Eagle River Landing
For years a picnic beach known only to bushwacking aficionados, Eagle River Landing is now a popular short walk on a gently graded trail. In the saddle (map on center panel), the new trail intersects the historic Amalga horse tram, dating back to a time when the only way to move freight to or from the Eagle River Mine up-valley was by once-a-week steamship service. This cove was the site of the steamship wharf, and the coastal terminus of that tram–though little evidence of either remains. Today, highways closely hug most of Juneau’s marine shoreline, so quiet, south-facing sandy beaches such as this one are rare. Eagle River Landing has otter haulouts and even a few marmots.
Few areas of the world experience glacial rebound. Most, in fact, now confront sea-level rise due to polar ice melt. But in northern Southeast Alaska, land is rising faster than is global sea level, a legacy of the Little Ice Age that peaked in the mid-1700s. Along marine shorelines, the increased regional weight of ice depressed the land about 10 feet. All of today’s homes, facilities and favored hiking trails on the map above would have been under water on an average high tide.
As ice waned, reduced pressure allowed the land to rise again. The current rate of glacial rebound is about 0.7 inches per year. Amalga and 26-mile Meadows have been transformed into a mosaic of freshwater wetlands, brush and spruce parkland, giving rise to the nickname “Risen Valleys.”
Much uplift habitat on the Mendenhall Wetlands was lost to development before establishment of the State Game Refuge; only at Risen Valleys–and at Cowee Meadows to the north–can we fully appreciate its value to wildlife.
The gifts of glacial rebound
In northern Southeast Alaska, land rising from the sea creates a globally unique habitat. Heavily developed near towns, first choice for public parks, “uplift meadow” with scattered groves of Sitka spruce also provides rich forage with nearby cover for bear, deer, long-tailed voles and Lincoln’s sparrows. Competition for this land is intense.
No scientific study has addressed the ecological importance of raised tideland. What are its geological underpinnings? What explains the delightful mosaic of subcommunities? How does it change over time?
Wildlife viewing etiquette
One of the great appeals of the Amalga Meadows trails is the chance to see wildlife. But as this area grows in accessibility and popularity, we could unwittingly “love it to death.” Places most appealing to outdoorspeople for the intricate parkland mosaic are also most valuable to sensitive species such as bear, wolf, lynx, deer, otter, mink, and ground-nesting birds. Considerate naturalists sometimes voluntarily avoid these “hotspots,” particularly in key seasons (spring) and times (dawn, dusk). Dogs have high potential to displace wildlife.
The large meadow north of the lodge currently has no trails, and that is by design. As we fill in Juneau’s last wild spaces, planners and trail committees are trying to meet the needs of wildlife as well as people. We can help them in the way we use public trails.
Over the years
1910 From 1905 to 1920 there was a large gold-mining community at the face of Eagle Glacier. Six miles of horse tram connected the mines to tidewater at Eagle River Landing.
This wonderfully accurate bedrock geology map was made before the days of GPS, laser transits, or even air photography. A few modern features are overlaid for reference. Berner’s Formation rocks farther up-valley yielded about a million dollars of gold.
Inset is Winter & Pond photo of the horse tram. Eagle Glacier, much thicker than today, shows in distance.
1948 Uplift meadows and tidal marshes provided some of the only Southeast habitat suitable for livestock. During the dairy period, soils were compacted, non-native plants introduced, and wildlife such as bears and wolves displaced. Inset is 1938 view west over Guernseys to Salt Chuck tidal gut in distance. Tides cannot reach this high today. Spruce saplings on right are now tall trees. Grazing impacts gradually shifted; in later 1962 photos, areas farther up- valley were trampled.
The Ackerman homestead passed to Joe Smith, then CBJ. The valley is now managed as a Natural Area.
1979 Cattle grazing ceased in the 1950s, but horses remained into the 1970s. In heavily trampled areas, red alders colonized; these are otherwise uncommon in uplift meadows and represent one of the positive impacts of grazing history because they now add to habitat diversity.
Subtle tone-shift in color infra-red imagery denotes boundaries of meadow subcommunities. Here, the low, wet swales are peach-colored, and the higher areas (grazed in 1948) are darker. These drier raised areas support scattered spruces in the 2006 photo below.
As the land rose, saltwater no longer backed into tidal sloughs of Amalga Meadows. But the streams remain valuable coho rearing habitat. Inset shows the old Ackerman Homestead in the 1970s; decay has since progressed considerably, but one roof still shows on the 2006 photo.
2006 The land is 5 feet higher than in the 1948 photo, when seawater poured daily into the Salt Chuck. But there’s still saline water at depth, enough to support marine invertebrates such as sea cucumbers.
Slight differences in elevation and sediment size determine where trees will grow. Pale grey areas in the meadow are higher and more suitable to conifers than the green swales along former tidal sloughs. By studying the gradual expansion of spruces, could you create a map of forest extent in the year 2050?
Access InformationTo Eagle River Landing
Distance: 0.5 miles
Elevation gain: 50 feet
Ownership: CBJ Natural Area
Notes: includes uplift meadow, old growth, 100-year second growth, and sand-gravel beach
To Kayak Beach
Distance: 0.27 miles
Elevation gain: 40 feet
Ownership: CBJ Natural Area
Notes: same as above, but shorter, and lacks mining-era second growth.
• Please don’t pick wild flowers.
• Do not feed wildlife.
Pack it out
• Carry out all trash.
• Please pick up after your pet.
Please respect SAGA facilities along the Kayak Beach trail by staying off the challenge course.