Ancient Trees

When you think of ancient trees, you probably think of petrified wood. You may be shocked to know that there are some ancient trees that are still living. The oldest known living organism is a bristlecone pine in Nevada that is over 5000 years old. When this tree sprouted, writing was a new concept and Egypt was under the rule of its first pharaohs. In fact, the pyramids weren’t even built yet, although Stonehenge was an active construction site.

Bristlecone pine (US Forest Service)

Other ancient trees are the giant sequoias of California in the 3000 year old range and limber pines date back to the 3^rd to 5^th centuries. East of the Mississippi, the oldest tree is a northern whitecedar in Ontario, which was just a gangly teen of 1100 years old when Columbus sailed the ocean blue. Other trees around the world are estimated to be over 3000 years old, with a yew in a Welsh churchyard that might come close to 5000 years old.

Limber pine

None of those ancients come close to the ages of some cloned trees. Clones are genetically identical to the parent tree. Rather than germinating from a seed, they grow from the parent tree’s root system. Genetically identical Huon pines in Australia are estimated to be 3000 years old. Norway spruces in Sweden, which normally live to be about 600, are growing from live roots that are estimated at 9000 years old.

The king of ancient trees is the Pando in Utah. The Pando is a grove of quaking aspens with about 47,000 trees growing from a single root system. The individual trunk parts of the aspens average 130 years old, but the entire system is estimated to be anywhere from 80,000 to a million years old. The heaviest known organism in the world, the Pando recently made headlines because it is dying. Like so much else in the world, the cause of death is human activity.

The Pando (Smithsonian)

This week's information comes from Wikipedia, of all places. Not to be trusted as a reliable source, it's a great place to find lists.

Daffy Ducks

This week, let’s have a look at one of my favorite critters, ducks. Mallards are probably one of the most common birds in North America. There have always been a lot of them near me, whether I was living in Pennsylvania or Washington. Many species are migratory, but my mallards are year-round residents. Growing up, I could always count on a few in the back yard, as we had a small stream separating us from the town park.

A pair of ducks swimming in a stream

There are two kinds of ducks- diving ducks and dabbling ducks. Diving ducks, as the name implies, dive underwater for food. Dabbling ducks like the mallard flip their butts in the air and their heads in the water to find food, but remain afloat. Different species have different food needs, but as a group they feed on fish, insects, worms, mollusks, and plants.

A mallard (a dabbling duck) goes bottoms up for food

A Barrow's goldeneye (a diving duck) beginning a dive

Females lay eggs in a nest, then lead their hatchlings to water. One year, a mallard nested in a tree in my parents’ yard. It’s a common practice among wood ducks, but at the time such behavior was unknown to me or anyone else in town. City workers came and got the ducks out of the tree. They didn’t believe it until they saw it. Ducks with tree nests usually nest right above a body of water. After hatching, the babies will plop out of the nest into the water, following mom’s lead.

Wood duck hatchlings leaving the nest (Pintrest)

One thing I’ve been guilty of in the past is feeding the ducks. Since they were frequent visitors, and because no one likes the end piece of bread, I would tear it into little pieces and toss it to the ducks. Bread isn’t part of a duck’s natural diet and can lead to health issues down the road. It’s better to let wildlife be wild and not count on people for food, but if you must feed the ducks, give them grape halves.

Mother mallard and babies

Ducks are known for their stereotypical quacking, but that sound belongs to the female mallard alone. She seems to be especially noisy in a large group of ducks. Probably the best duck sound is the mutter. I notice this if I’m on a bridge or at the water’s edge and a duck swims by. They sound to me like they’re muttering something under their breath at me. My favorite duck behavior occurs during mating season. On many occasions, I’ve seen half a dozen or more males chasing a female around the back yard. There’s nothing like a bunch little footballs with heads waddling around as quickly as possible.

Maybe you see a lot of ducks in your area too. Are they so common as to become almost invisible? Slow down and take the time to watch them.

Species of the Month

Halloween is right around the corner, so it’s time for another creepy crawly species of the month. We’ve covered bats and owls, so this year we’ll go to the spiders. Stop reading here if they creep you and come back next week. Grass spiders are a genus of several funnel weaving spiders, including the Pennsylvania grass spider. You’ll likely start noticing these robust spiders in your house as they venture inside to avoid the falling outdoor temperatures. We associate spiders with Halloween because they are at their biggest after growing all year.

Pennsylvania grass spider at my sister's house

Scientific name: Agelenopsis species

Kingdom: Animalia (animals)

Class: Arachnida (arachnids)

Order: Araneae (spiders)

Range: All of North America except Arctic areas

Habitat: Lawns, your house during fall

Grass spider in its natural habitat (Penn State)

Lifespan: One year

Diet: Insects

Predators: Birds

Conservation Status: No special protection

Grass spider in its web (Missouri Department of Conservation)

Other Information: Grass spiders build funnel or tunnel shaped webs in the grass, hence the name. Females lay eggs in sacs during late summer or early fall, with eggs hatching in spring. The eggs survive over the winter but adult spiders do not. Grass spiders are fast and typically avoid humans, but will occasionally bite with trapped and threatened. Information this week comes from Insect Identification, despite spiders not being an insect.

Symbiotic Fish and Forests

With the arrival of fall, salmon spawning is in full swing in the Pacific Northwest. Being a fish, they obviously interact with a lot of other sea creatures and aquatic life. They also have a symbiotic relationship with the forest, believe it or not.

Fish and forests, at first glance, are as different as, well, fish and forests. But despite being a water-based critter and chunk of land, they interact with each other splendidly. They feed each other. I’ll explain how, starting with the how the forest helps the salmon.

McClane Creek, an example of healthy salmon habitat

Forest trees are crucial to salmon habitat. Despite living in a river for part of their lives, salmon lean heavily on trees for survival. Salmon need cool, clean water. The forest keeps the river clean by slowing the flow of surface water and the sediments it carries. Sediments can clog their gills and cover the rocks where they lay their eggs during spawning. Shade from the trees keeps the water temperature at acceptable levels during the summer. Warmer water loses dissolved oxygen, and salmon are very picky about temperatures.

Pink salmon returning to the cool, shaded water of Nisqually River

Fallen trees in the river create habitat diversity. The large woody debris forces the current to change, creating deep pools on the downstream side of the obstruction and changing the complexity of the stream bed. The deep pools provide a place to hide from predators and respite from high flows during the rainy season. The large woody debris adds nutrients to the ecosystem as it decomposes. It also contains or attracts tasty insects for the salmon to munch on.

Artificial logjams like this are used as habitat enhancement
in salmon streams.

The salmon help replenish the forest by provided nutrients (nitrogen in particular) from the sea when they die. Predators are the immediate beneficiaries of the ocean’s bounty, but the forest as a whole benefits. Plenty of leftovers decompose both in the river and on land. As the fish decomposes, or after a bear poops in the woods, the trees and other plants absorb the nutrients so they can continue to give back to the salmon and the cycle continues for another season.

Salmon bones replenishing the Hoh Rainforest

It was once thought that removing obstacles like large woody debris was an improvement to the riparian habitat. Now we know better. In some areas, workers are dropping downed trees into rivers. In others, engineered logjams do just as well. Watch this short video about riparian restoration for the benefit of salmon and flood control in Oregon.

Superfund Site

While I was working toward my environmental science one of my classes was Environmental Law and Policy. For one of our assignments we had to research a Superfund site and present to the class. The site I chose was less than a mile as the crow flies from where I grew up. At that time, EPA hadn’t begun work on the site. Last year after moving back to Pennsylvania, I attended an EPA meeting on the status of the cleanup. This year, as work nears completion, I was able to tour the site with EPA’s Tim Gallagher.

Contrary to what you might think, not all Superfund sites are full of leaking drums of glowing green radioactive waste. The Watson-Johnson property was a landfill from the 50s to the 70s, then forgotten about. In the late 90s, water testing revealed several contaminants in the groundwater. One of the town wells for the water supply was closed. The solution the EPA came up with was to cap the landfill and use chemical injection to neutralize the contaminants in the groundwater.

Watson Johnson landfill site. The geosynthetic is
buried under 18 inches of soil here.

Capping the landfill is a common practice at sites like this. Why not remove the waste? Odds are, everything would just be taken out of the ground and buried in another landfill somewhere else. One oozing container was discovered and removed from the site, but otherwise it was all collected together and capped. The cap uses a layer of compacted clay soil, a waterproof synthetic fabric, more soil, and vegetation. The purpose of the cap is to keep the waste contained and keep water out, preventing anything from seeping into the groundwater.  Water drains to wetlands, ponds, and level spreaders. Level spreaders are cement cisterns that capture water and allow it to overflow and slowly spread away from the site.

Drainage swale around the outside of the capped landfill.
Grass seed has already been spread inside it.

Level spreader beyond the edge of the capped landfill

The soil above and around the cap is contoured to divert surface water away from the cap. There are natural wetlands on site, as well as new artificial wetlands created to contain and disperse runoff. The cap itself layered in a way that creates pathways for gases flow towards several vents. Because they site was once open but now is closed with those release points, concentrations are higher. Methane has been noted at the vents, but not volatile organic compounds (VOCs).

Gas vent. No monitors are attached.

Monitoring and injection wells reach the groundwater. Sodium permanganate is injected to react with the chemicals in the water. The reaction breaks down the chemicals (including the sodium permanganate) into harmless elements like oxygen and hydrogen. Monitoring wells are set up to test the levels of chemicals in the water. Injections will stop once the concentration goes below 100 parts per billion. At that point, EPA will begin bioremediation. Microscopic critters that eat the contaminants will be injected to the groundwater to bring the contaminants down even further.

Work on the site is nearing completion. Despite a cold winter and rainy summer, work is only two months behind schedule. Workers are currently adding a layer of topsoil six inches deep on top of the cover soil. Once topsoil is in place, it will be seeded with native grasses. Around the cap, workers are setting up deer fence to protect new trees that will be going in. Landscaping was supposed to start last week but was delayed by heavy rain.

EPA will continue to monitor the site for a year after completion, before turning that duty over to the state. Future plans include nesting boxes for swallows and bats. The new trees will create a nice matrix with the older existing woods on the edge of the site, which should attract songbirds that prefer new growth. The site is privately owned, so it will not become a park like old landfills in other areas. However, development will be limited by cap so it will likely remain a nice green oasis as the area becomes increasingly more urbanized.

For more information visit the EPA's Watson Johnson website. Special thanks to Tim Gallagher for taking time out of his day to show me around.