Here are some pictures from way up near the headwaters of Grizzly Creek. The forest is right on the redwood transition areas where redwood and coastal Douglas-fir and oak woodlands collide. The combination of good soils, heavy rain, and persistent fog make these areas very productive for trees.
These mountain streams may look small, but once the rains start they really pick up. Most of the headwater areas transition to open grasslands, and as result the peak flows into these streams is enormous. Flows tend to be flashy and can be very intense right after big rains.
This particular forest came with an interesting story. Most of the surrounding areas where logged in the 1960s. Apparently as they moved into this stand, there was a horrible accident, costing one of the loggers their life. The crew backed out after the accident, leaving this area unlogged. And so it has stood until now. And so it will remain, now that a northern spotted owl has found its home here.
As you travel east and into higher elevations, the forests begin to transition to a mixed conifer type, which is generally defined as Douglas-fir and/or true fir with pine and various hardwoods. Mixed conifer forests are pretty complex and can vary widely across the interior of the state, but thats another story.
Only the eastern and more remote portions of Humboldt county have these types of forests, though occasionally you may find islands of habitats that resemble mixed conifer and form unique areas on the landscape. (e.g. willow creek, south fork mountain, etc.) This place is near the pilot drainage and is nestled within a thousand acre oak woodland, where just about 10 acres have developed into this unique forest island.
Here is another example of what I would say was natural encroachment of oak woodlands, or better put, succession. There are a few aged white oak trees, but they are in severe decline. Most of the woody debris on the ground and standing snags are white oak, a last testament of what was there a few hundred years ago. This forest obviously developed with fire as all the trees have layers of fire scars, including this madrone.
Here is a good view of a stand that has almost fully transitioned from a black oak forest to a Douglas-fir stand. Encroachment began in this stand in the 1960s and finally the last of the taller oaks are reaching the end of their lives. Over then next ten or so years the oak stems will loose all of their limbs and begin to feel the pull of gravity as their root masses die. Many species of insects and fungus will invade these trees and speed up the fall. Once on the ground, the boles will persist for decades as the forest recyclers slowly and consistently do their work.
Meanwhile the Douglas-fir canopy will close in around the space previously occupied by the oaks and the little remaining areas of filtered light on the forest floor will become dark. This will also effect the shrub and ground cover component of the forest, severely limiting what can grow there in the absence of light.
Its interesting how the full encroachment cycle changes the bio-diversity of stand over time. It would seem that during the last phases of transition, like in the photo, the diversity is highest. This is in part due to the vertical structure offered by the overstory conifer, the decaying oak trees in the mid canopy, and the collection of downed wood on the forest floor. There are also pockets of shrubs that still receive light where the fir canopy has not closed in. Oak snags make potential cavities for numerous birds and mammals. The fallen trees become home to hosts of insects that in turn are feasted on by many of the locals.
While I generally speak of this encroachment as a negative, there is certainly a positive, or at least productive element to this process from a forest health prospective. In a truly “natural” setting, there would be recruitment of oak woodlands somewhere near-by while this process was occurring, creating the balance of habitats over the landscape. However in our fire starved environment, Douglas-fir encroachment is occurring much more frequently than the rate oak stands are developing. In fact, very little oak stands are developing at all in Humboldt County. This is why, I believe, that there is an urgency to prevent encroachment into woodlands.
Leave it to children to be able to find neat places that you would otherwise never see. How often are you at a place like Moosntone Beach and have the desire to go crawl through the brush just to see whats in there? I used to have that urge, and while I do crawl through the brush at work, its the last thing I want to do when Im not working. But its hard to turn down your kid, so adventure it is. Lead on boy!
He had been going on and on about this so-called “sand slide”. Essentially Moonstone Rock is a sandstone bluff, almost completely covered with a mat of English ivy. Animal paths have been expanded by kids and make a maze of tunnels to explore. Once I got in there I remembered exploring these ivy tunnels as a teenager.
Although this is an exotic, invasive species – it sure is pretty looking. Who doesnt like to look at a ivy covered castle or brick wall? And ivy caves make for wonderful adventures. Once they really dominate an area like this, there is certainly habitat for many birds and mammals.