Most of this page may also be found on the Friends of Silver Falls State Park webpages at http://www.open.org/slvrfall/Nathist/foodcycl.htm . I have volunteered many hours since 1993 at Silver Falls State Park. Among the things that I have done are creating the Friends webpages, leading nature hikes and making videos. I feel that this page is one of the most important things that I have done as this important information is not really in the mainstream body of knowledge.

What makes a forest?

You are missing a great mushroom GIF.Silver Falls Park is a fine example of the way that plant communities interact with animals and mushrooms (the scientists call them "fungi") in a temperate rainforest.

The area around the South Falls Lodge is located on basalt (see the Geology pages for an explanation of this). The soil is actually only thin layer of dirt covering this solid rock. If you walk around in the trees by the top of South Falls, you may be able to feel and hear that the soil is probably only six inches to one foot deep in many places.

The Park receives over 80 inches of rain each year. If it all fell at once and was collected, it would be one foot over the head a 5' 8" person!!!! With the amount of rain that falls annually, most of the nutrients that plants need to grow are washed out of the soil, down the side of the canyon, into Silver Creek, into the Pudding River, into the Willamette River, into the Columbia River and finally into the Pacific Ocean. This is an example of what happens throughout the Pacific Northwest.

If the nutrients aren't stored in the soil, how do the trees and other plants stay alive?

Most of the nutrients in our forest are stored in the plants living above the ground ("overstory" is the word scientists use). This is the reason that foresters don't take soil samples to check the nutrient levels in the soil like a farmer would. The foresters take small cuttings of the tree needles to see if the trees are healthy.

Many people recognize some of the fungi that live here. You are missing a great mushroom GIF. When the fungi fruits (like an apple or pear tree does), they form mushrooms. Some of these mushrooms are collected and eaten by people. Others have value as medicine. Since it is so wet here and there is plenty of material for fungi to digest, we have many different types of fungi. Scientists list ("classify") fungi in several different categories. These are based on different characteristics including how the mushrooms reproduce and the shape of their spores (if mushrooms were plants, the spores would be their seeds). One of the ways that mushrooms are further described is by the way that the fungi get their food.

Some fungi digest live plants or trees (these are called "parasitic"), some digest dead plants and trees (these are called "saprophytic") and some form thread-like "roots" (called "mycelium")You are missing a great mushroom GIF. that digest organic matter in the soil. The individual strands of these fungi wrap around the roots of trees and actually grow into the roots. Plants make sugar from the nutrients in the soil and energy from the sun (in a process called "photosynthesis"). The plants share some of this sugar with the fungi. This is food for the fungi. The fungi spread through the soil over an area larger than the roots of the trees do and digest the organic matter in the soil. The fungi share the nutrients that they release from the soil and don't use with the trees. The fungi also aid the trees in the uptake of water from the soil so the trees are able to better survive periods of drought. When two living things share food with each other and neither harms the other, this is called a "symbiotic" or "mutualistic" relationship.

Where do the nutrients that the fungi release come from?

When a plant or part of a plant dies, it falls to the forest floor. The spores from the fungi are carried by the wind and animals. Living plants have protection against most spores that keeps the plants from getting "infected" by the spores. When the plant material (all of the living and dead plants together are called "biomass") dies, this protection is no longer available and the spores that land on the dead material may start to grow.

There are many other inhabitants of our forests. We have deer that eat the brush and rabbits that nibble the grass. When the animals digest their food, they leave behind the remains on the ground (don't step in any!!!). This is the first step in releasing the nutrients from the trees and plants back into the forest food system.

You may notice some smaller animals in our forest. One of these is an arthropod that is black with yellow dots along their sides called a millipede. These millipedes eat much smaller organic matter than the deer and other large animals do. After the millipede eats, for example, a needle from a Douglas Fir tree, it digests it and leaves behind a "millipede muffin" (you probably won't notice these droppings unless you have a magnifying glass so you won't care if you step on them!!!). When the millipede's food travels through its digestive system, it gets water from the millipede. This water is left in the millipede muffin and makes the m.m. a perfect place for the spores from some fungi to grow.

There are many smaller arthropods that live in our forest soils. Some of these are so small that you would need a very powerful electron microscope to see them. Many of these arthropods live on the fungi that grows on various dead pieces of organic matter in the soil (including the millipede muffins). The cycle of digesting, depositing, digesting and depositing continues until the nutrients in the soil are released for the trees to use or are carried to the trees by the mycelium of some of the fungi. You may think that there might be some of these tiny animals around but you may be surprised to find that scientists estimate that there are over 150,000 of one type called oribatted (how IS that spelled anyway?-{) mites in one square meter of healthy coniferous forest soil!!!

This is a shot of an oldgrowth tree that has red-spored butt rot.

This tree was around when Columbus landed in America.
It is the host for Phaeolus schweinitzii (Dyer's Polypore or Red-Spored Butt Rot).
It was cut down as it posed a threat to people visiting Bagby Hot Springs.

This is a shot of red-spored butt rot mushroom.

Although there were no fruiting bodies around the tree above, here is a shot of Phaeolus schweinitzii on a nearby stump.

The nutrient chain in our forest is really one big circle!!!!


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