Week 7: A Little Decoration for the Trees

Date: Saturday, May 19, 2013

Weather: Partly Cloudy, Windy

Temperature: 47ºF

Time: 12:00 PM -1:00 PM

Location: Union Bay Natural Area, Seattle, WA

Back at Union Bay Natural Area this week! Amidst all of the cotton flying around, here’s the view of my observation site this week.

A beautiful spring day at my observation site.

I got a firsthand look at how destructive an invasive plant, the Himalayan Blackberry, can be. When I first entered my site, I noticed that a large branch of an apple tree had split and was only attached to the rest of the tree by a few fibers. After looking down, I realized that the branch had gotten too heavy because many Himalayan Blackberry twigs were weighing it down.

Besides that tragic sight, the most noticeable change was how tall all the plants were growing. The plants are sort of like children, you turn around for one second (in my case, went to a different site for a week) and suddenly everything doubles in size. The grasses and sedges are now at the height of my shoulders. Also, on the base of leaves and on various branches, I noticed a milky-white foam has appeared. It turns out to be the spittle of a Meadow Spittlebug (Philaenus spumarius). The nymph form of the spittlebug is actually inside the foam as it hides from predators and shields itself from the environment’s varying temperatures.

A few spittlebugs in their nymph form.

Up above were some American Crows flying in the area, fighting over food scraps as they clawed at each other. Perhaps it was because I visited my site at a later time than usual, but I noticed a disproportionately large number of crows compared to any other bird species.

Meanwhile, as I looked around, I saw many leaves emerging from a Black Cottonwood tree. The leaves are especially glossy in color when they have just eclosed from the leaf bud. The orange and red leaf buds I had mentioned in a previous post have also gotten larger and there are many more of them.

The Bitter Cherry tree has also grown in size as its twigs now extend over the trail. Many fruiting bodies have formed and they are changing from a green to yellow color.

Bitter Cherry fruit that has changed from a green to yellow color.

There was all sorts of activity occurring in the marsh. There are now many Yellow Water Lilies covering the water surface as they grow larger in size. The Yellow Irises have proliferated in the marsh and are currently flowering in earnest. While it is a pretty sight, the Yellow Iris is an invasive species, which means it is taking many types of resources from the native plants nearby. It is rather sad to see that it has actually infiltrated almost every corner of the marsh.

Yellow irises growing and blooming everywhere in the marsh.

There were two Eastern Painted Turtles residing on a log and I’ve come to notice, their favorite position is to actually angle themselves upwards and stretch their head as far out as possible. I’m still unsure why this position is ideal because the turtles simply freeze in that pose for the length of my stay at my observation site. They are not feeding nor interacting, but perhaps this is the best way to maximize the surface area that sunlight can hit, so they can stay warm.

On another log, I saw a Mallard nest. What first caught my attention was that the male Mallard looked like it had bit one of the ducklings and the female Mallard became highly aggressive. The female flapped its wings and bit the male fervently until the male finally flew away. After that agitation, I realized the female Mallard was protecting at least six ducklings in the nest and each of them was getting cleaned by their mother. When the mother was finished, all of the ducklings got into a line and followed their mother out of the nest and swam out towards the lake.

A Mallard’s ducklings following their mother in a single file line.

Nearby was a busy Marsh Wren (Cistothorus palustris) that was hopping along the shore of the marsh to feed on small insects. After feeding, it would grab twigs and bits of cotton and then fly back into the Cattails. The Marsh Wren was working hard to build its nest!

As I mentioned before, bird activity was pretty low today, probably an artifact of my later visit. There were some Red-Winged Blackbirds making calls far out in the distance and Canadian Geese flying overhead. There were also some American Coots dabbling farther out in the lake. In addition, many Savannah Sparrows were flying from branches to the grassier areas. They were probably attending to their nests and for fear of stepping on a nest, I decided to stay out of the grassier areas.

One Savannah sparrow actually led me right to what I was trying to find. Today’s assignment is to look out for fungi and lichens and the sparrow was perched right on a tree covered in lichen.

My helpful lookout for the day, the Savannah Sparrow.

I had spent most of my time searching around logs and the base of trees for mushrooms, but with no luck. It turns out there were many fascinating lichen to look at instead. On an apple tree were three types of lichen. The first was the Hammered Shield Lichen (Parmelia sulcata), a foliose lichen. It is a gray-green lichen with rounded lobes. The lobes have ridges and depressions, so it looks like it has been hammered. The lichen was growing in patches on the branches and tree trunk. It would grow on a branch node and then expand outwards. When the lichen was growing on a branch, it would only grow on one edge of the branch instead of completely enveloping a branch.

An example of Hammered Shield Lichen growing on an apple tree branch.

The second type of lichen was the Oakmoss Lichen (Evernia prunastri), a foliose lichen. This type of lichen was not as prevalent on the tree and only grew at the locations in which a branch was split to become two new branches. The lichen is a green color with a yellow tinge on the top side and white on the bottom side. It grows in a forked, branching pattern. The lichen was also very thin and papery in texture. The last type of lichen was the Common Orange Lichen (Xanthoria parietina), another foliose lichen. This lichen grew in small patches, only on the edges of the branches. It appeared to grow in little yellow-orange disc shapes, but were very tightly packed in one location.

It was interesting to see how all of the lichens occupied the same branches, but each had their own niche with the Hammered Shield Lichen being the most prevalent.

Left, the Oakmoss Lichen growing on an apple tree branch. Right, all three types of lichens residing together on one apple tree branch.

I also spotted another form of lichen, a crustose lichen called Phlyctis argena. This lichen grows in white circles and ovals on the trunk of the Red Alder and looks like it’s a part of the trunk. The lichen has a felty texture. I’m not sure if there is a studied relationship between this lichen and the red alder, but I didn’t realize I have been using the white patches of lichen as a way to ID the tree.

The signature patches of white on the Red Alder bark are actually a lichen!