Ravenna Park Walking Tour

This walking tour is at Ravenna Park. It is a ravine that possessed old-growth timber.  Ravenna Creek locates at the west side of the ravine alone Brooklyn Avenue NE. The Cowen Park Bridge crosses the park from north to south on 15^th Avenue. We are now at the Ravenna Park Softball field. We will walk through the park, and we will stop by 10 stations at the park. 

1. Land-use History
For our first stop, I will introduce some land-use history of Ravenna Park. About 50,000 years ago melt-off from the Vashion Glacial Ice Sheet that once formed Lake Russell cut and shape a ravine through new glacial fill. The first pioneer settlers began making land claims in Seattle, brining logging industry in the park as well. However, the steep ravine made the task far too difficult and its huge trees and massive ferns were spared that fate. After a couple of years, Ravenna became an attractive site to home buyers. Then David  Denny help found the Rainier Power and Railway Company in order to facilitate easy transportation to the nearby University District. That line was extended to Ravenna Park around 1892 and three years later was reorganized as the Third Street and Suburban Railway, which included a Ravenna Station (near today's NE 58th Street and 20th Avenue NE). In 1986 the City used the ravine for a major stormwater drainpipe installation project. The Ravenna community protested against the City (Historylink.org). 

2.Medical Herbs Uses
The origin of using herbs as medicines can trace back to thousands of years ago. Native Americans also have the tradition of using herbs. As you walking down the trial you can see some plants include Oregon Grape, Pacific Yew, Maple etc.  Tea from the inner Maple bark can use for coughs, and many people use maple for making syrup. The powdered or dried root of the plant was used to sooth lung ailments including asthmatic and bronchial spasms. This is an Oregon Grape, and it can be used for stomach ulcers, stomach upset, and to treat infections. This is a Pacific Yew. The bark of it can be extracted for swollen tonsils, seizures, muscle and joint pain.   

Pacific Yew

Oregon Grape

Big leaf Maple 

3. Birds- The major trail along the stream

A Song Sparrow

Birds are everywhere as long as you pay attention to them! Ravenna Park is definitely not the only site for observing birds, but this forest does benefit many birds to habitat and forage here. I personally spotted Brown Creepers, Black-capped Chickadees, Song Sparrows, and many American Crows. It can be hard to see woodpeckers here, but you can definitely hear a lot of them when you walk through the park. You can observe many common Northwest birds in here. You may see the birds anywhere in the park, but I personally think this central place of the ravine where near the stream is a great location. You can always see many crows defend their territory on these trees. Check out this website if you want to learn some bird songs to identify which bird is around you:
Xenocanto.org

4. Animal Behavior - Birds Call

Now close your eyes, take some time and listen carefully to the birds' songs around you. What are you hearing? A Song Sparrow? A Hairy Woodpecker? An American Crows? Or multiple birds song responding to each other? Singing is an important day-to-day activity to birds. Two important reasons are attracting mates and claiming their territories. We hear mostly males singing, because they typically take the lead in defending territories and attracting mates. However, especially in the tropical area, both male and female species are involving in this animal behavior. Many birds use alarm calls in response to a predator nearby. In Ravenna Park, you can hear many Black-capped Chickadees. They give a chicka-dee-dee-dee alarm call. Usually more "dee" sound means more severe threat they are facing. 

Black-capped Chickadee

5. Geology-Erratic

The Ravenna Park was formed when Vashon Glacial Ice Sheet melted and formed Lake Russel and cut ravines through new glacial fill. Then Lake Russell disappeared when the Ice Sheet retreated north of the Straits of Juan de Fuca, but various geologies remained, including the Green Lake basin. This big rock is the evidence of glacier used to cover this region. It most likely came to the Salish Lowland via the Cordilleran ice sheets that descended the Fraser River. Probably all of these erratics in this region are from the final advance, the Vashon, which sat over the Seattle area for only a couple thousand years, between 18,000 to 16,000 years ago. The maximum ice thickness was around 3000 feet at Seattle (Tucker, 2011).

6. Plants - Under the bridge
Ravenna Park is perfect place to observe plants. It has a large collection of plants throughout the park. You can see many ferns include Sword fern, lady Fern, Deer Fern, and Licorice Fern, trees such as Douglas Fir, Grand Fir, Big-leaf Maple, and berries such as Thimble Berry, Salmon Berry, and Himalayan Blackberry. The most interesting plants I found were Skunk Cabbage and Horsetail. When I first visited the park during the beginning of the spring, the Horsetails were just about my ankle tall, and were barely sprouting. After 10 weeks, they were surprisingly about my hip tall. This is a Common Horsetail, another common species in the Northwest is Giant Horsetail, you can find it in the Ravenna and Union Bay Natural Area. The other interesting plant I found were Skunk Cabbage. It has yellow, parallel-veined spathe, giant green leaves, and of course skunky smelling.

Skunk Cabbage

Sword Fern

Common Horsetail 

Thimbleberry

7. Invertebrates - stream
We are going to observe some invertebrates in the stream. There are two basic groups of animals: invertebrates and vertebrates. The fundamental difference between two groups is invertebrates do not have backbones. I personally saw many mayflies in the Ephemeroptera Order and stone flies in the Plecoptera Order before. The best way to see stream invertebrates is to collect water with a glass jar for a couple of times, and look carefully to the jar.  Sometimes just flip over logs or rocks, open folded leaves, and trace any flying objects. It is also very hard to identify the species of invertebrates because they are so tiny to see the details. These stream invertebrates include Mayflies and Stone flies are indicators of clean water. Now spend some time looking at the stream, and gently rolling over rocks and logs, you may find some surprises!

8. Lichens/ Fungi 

Most Fungi obtain food from organic matter, and they do not participant in photosynthesis. Fungi reproduce through the release of single-celled bodies called spores. Many mushroom growing in the Northwest are deadly poisonous to eat, so be careful when you touch them, and make sure they are safe and nontoxic. Here is an example of Artist's Fungus. It usually grow low on trunks of dead or dying trees. Lichens are dual organism made up of a fungus and algae or cyanobacteria. 

Artist's Fungus 

This is a twig that I found has two lichens on one branch, which has a Hammered Shield Lichen and a Oakmoss Lichen.

9. Ecological Disturbance- Invasive Species 

Himalaya Blackberry

For this station, we are going to look at a invasive species in the park, which is a negative example of ecological interaction. Himalaya Blackberry is native to Asian. It can adapt to a variety of environments. They are found throughout the Washington. To distinguish it from the native berry remember that leaves are large, oblong and toothed, and typically come in sets of three or five, and have robust stems. Another major invasive species in the park is English Ivy. There are some volunteers and workparties held by Seattle Parks Department working on the invasive species removal include Himalaya Blackberry and English Ivy. 

English Ivy

10. Ecologic Interaction -Nurse log
This is an example of the nurse log, which is an ecologic interaction within the nature. A nurse log is just a fallen tree, but can provide habitat for plants to live atop it, nursing new life. The roots of new plants take up the nutrients of the old fallen tree. Nurse log is one of characteristics of the old growth forest. You may see many of these in the forest. There are some trees fallen into the stream as well. The nurse log can also provide nutrients to the insects living in the stream.