They've Got Connections...
Though the coast
redwood is not affected severely by any sort of diseases, recent
studies show the pathogen
Phytophthora ramorum, or
Sudden Oak Death, is now known to have
an effect on
Sequoia sempervirens, along with more than three dozen other plant
species in California. Luckily though, there is still no evidence that mature
redwoods are harmed by the pathogen.
is a parasitic water mold that has a wide range of hosts among
native California plants. Even if redwood seedlings and sprouts
are affected, the possibility that mature redwoods could show
resistance to infection still remains. Even if further research
specifies that redwoods are not significantly affected by Sudden
Oak Death, the disease still creates a major threat to the
ecosystem of the coast redwood. The most vulnerable species, tanoak, is a very common tree in the southern range of the redwood
forest that several animals depend on for food and shelter. The
death of these trees could potentially put the forest at risk
through loss of food and habitat, and thus could raise the total
amount of combustible material in the area, resulting in more
severe fires that could kill larger redwoods and Douglas firs.
As mentioned in the earlier section, Adaptations, redwoods have no insects that cause serious damage. However, several insects are found living on the redwood. These include a flatheaded twig borer and girdler, two redwood bark beetles, and the sequoia pitch moth.
When growing with other species of trees, redwoods are usually the dominant tree. Although this is true, it is generally mixed with other conifers and broad-leaf trees. Douglas fir can occupy dominant and co-dominant positions along with the redwood, competing with them for height. Common species of trees on the coastal side of the redwoods include grand fir, western hemlock, and Sitka spruce. The Sitka spruce outcompete the redwoods in these areas because they are able to endure salty conditions. These trees assist the redwoods by shielding them from salt and wind. Other conifers found mixed with the redwoods include Gowen cypress and various species of pine.
The two most common hardwoods in the redwood areas are tanoak and Pacific madrone. The tanoak grows far beneath the towering redwoods, where its seedlings can tolerate shade better than redwoods. In addition, their acorns establish themselves on the forest floor more efficiently than the seeds of most trees. Other hardwoods found with redwood are vine maple, bigleaf maple, red alder, giant chinkapin, Oregon ash, Pacific bayberry, Oregon white oak, cascara buckthorn, willows, and California-laurel. The most common species of lesser vegetation found in association with the coast redwood are bracken, sword fern, azalea, California huckleberry, Pacific rhododendron, salmonberry, coyote-brush, and snowbrush. The redwoods provide protection and shelter for these plants and various others.
The redwoods offer shelter to many animals as well such as birds like the spotted owl and the marbled murrelet, both of which nest almost exclusively in old-growth redwood and Douglas fir forests. Two species of threatened bird species that depend greatly on the bay near the coast redwoods for food include the peregrine falcon and the bald eagle. Red tree voles, relatives of mice, live almost in the very tops of the redwood trees, eating the needles. Deer ticks that carry Lyme disease also occur in the coast redwood forests. Other animals found among the coast redwoods include mammals like black bears, elk, deer, cougars, raccoons, squirrels, and martens. Unfortunately, the black bear has been known to cause serious damage to parts of the redwood region by stripping the bark of the trees. Wide sections of bark are torn from the tree mainly during the months of April to August. Younger, thinner trees are damaged the most by this occurrence. Click here to read more about this issue between the black bear and the coast redwoods.
In figure (A), I captured a photo of the rare teddy bear species while I was out walking through the Prairie Creek State Park. There are not many sightings of this vicious creature, so I was very lucky to have caught the wild beast on camera. However, the more common species one would normally find in the Redwood State Parks is Ursus americanus, generally known as the black bear (B).
The banana slug is also a very common organism found among coast redwoods. Banana slugs chew leaves, waste from other animals, and dead plant material, which it later recycles into soil. In addition to working well as decomposers, they also benefit the forest by spreading seeds and spores of different plants through their waste. These slugs eat everything but redwood seedlings and seeds.
forestsalso contain various organisms in the forest soil where fungi, microscopic invertebrates, and bacteria play critical roles in nutrient cycling and overall forest health. One common species of fungi often found growing beneath coast redwoods is Caulorhizae umbonata, also known as the rooting redwood mushroom. Luckily, this fungus does not harm the coast redwoods in any way. More fungi associated with the coast redwood are members of the phylum Glomeromycota. Species of this phylum form mutualistic relationships between the roots of plants and fungi called mycorrhizae. The fungus benefits from this relationship by obtaining sugars from the plant, while the plant benefits by acquiring an increase in surface area to allow for greater absorption of water and nutrients.
If you would like to know more about any of the following organisms that are connected to the coast redwood, just click on the website!
Peregrine falcon: http://bioweb.uwlax.edu/bio203/s2008/lauterba_jona/
Sweet violet: http://bioweb.uwlax.edu/bio203/s2008/tacke_kati/
Lyme Disease bacteria: http://bioweb.uwlax.edu/bio203/s2007/joyce_kait/
Even more organisms can be found by going to:
Click on Human Impacts to learn how humans have affected coast redwoods throughout history.
Go back to Reproduction.