From Wildflowers of the Trinity Alps. Photo by Ken DeCamp.
Green plants are considered autotrophs because they photosynthesize—making sugar from water and carbon dioxide. The world of heterotrophic plants is complicated but all have moved away from total energy production from photosynthesis toward obtaining organic carbon either directly from other living beings or through a parasitic relationship with a fungus. Heterotrophic plants include directly parasitic and mycotrophic forms. The conifer forests of the western United States nurture an exceptional diversity of heterotrophic plants and the Klamath Mountains may have the most heterotrophic plants in the western United States!
My elegant crossing Tule Creek. Photo by Josh Smith.
Last weekend, I hiked in Trinity County along a low-elevation, fire-prone section of the Bigfoot Trail between Highway 3 and Hayfork and was able to witness obligate & facultative seeding in action.
One-third of manzanita species are facultative seeders. These are species that regenerate post-fire by both seed and burl resprouting. The remainder are obligate seeders that lose their entire adult population in a fire and depend on a seed bank for regeneration. Obligate seeding is the current model in manzanita evolution.
To understand why, consider the climatic dynamics over thousands, or tens of thousands of years or more. In the case of the resprouting species, particular individuals can live for centuries, resprouting over and over, cloning new individuals as the burls expand with each fire cycle. But in that population, the rate of genetic change is limited, because most individuals live a long time by way of asexual reproduction. This suggests that populations may be unable to respond to rapid climatic changes that might occur in only hundreds of years. The obligate seeders, on the other hand, lose all adults in stand-replacing fires and new post-fire generations have to establish from more genetically diverse seeds. Those populations consequently have greater flexibility to shift and adjust as circumstances require; traits that might have been rare and less important in older generations can emerge through natural selection and become critical in the newer generations within the lifetime of resprouting manzanitas.
Much of this area burned in the summer of 2015. While evidence of the fires were everywhere, there are many signs of the next generation of plants returning to the landscape. This was particularly true on some of the south-facing slopes above Philpot Campground where two species of manzanitas were exploring different reproductive regimes– both obligate & facultative seeding.
Arctostaphylos manzanita is a facultatative seeder. It can resprout by seed but also from dormant buds. When present, these structures are often prominent and are called burls (also ligno tubers)–seen in the middle of the sprouting leaves.
Arctostaphylos canescens is an obligate seeder and does not have a burl. Instead, genetically unique seedlings resprout from a well-stocked seed bank.
Select Forest Pathogens of California’s Klamath Mountains
Forest Pathogens often go unnoticed while exploring, but offer an exceptional window into the intricacies of forest ecology when better understood. I created the free document linked below in 2011 while in Grad School at Humboldt State. Forest Pathology was one of the more interesting classes I took while turning Conifer Country into my thesis for a Master’s Degree in Biology. Most of the information for this document was taken from Terry Henkel’s lecture notes as well as from internet and book sources–all cited within the document. I was recently reminded of this creation because of the October weather that has dropped unprecedented amounts of rain and nurtured fungal growth across Northwest California.
I recently started a citizen science project with 5 classes of high school biology students from Fortuna, California. The plan is to combine their observation skills with the technology offered by iNaturalist. Each month they will visit Rohner Park and record data on a chosen spot in the forest–looking for plants and animals as well as changes in canopy and ground cover. As they become more proficient in species ID, students will also upload observations to our iNatural Project ultimately creating a field guide to their local forest. We all know how much I like field guides…
My plan, over future visits to wilderness areas, is to start similar citizen science projects. The first attempt at this wide-ranging project began this week on a visit to the Bear Peak Botanical Area on the Klamath National Forest. I originally wrote about this area in my book Conifer Country because it is unique in many ways, including the populations of yellow-cedar found here. This species in common further north, but quite rare in California.
Quaking aspens (Populus tremuloides) in the Blackrock-High Rock Desert.
Fall is coming.
For me it is a time of rejuvenation and also my favorite season. With the shift of the California Current, rains begin to fall in California after a summer of drought. The high country along the Pacific Slope finds snow returning. While we retreat inside our homes, native plants and animals must adjust to the changes. Some birds migrate, mammals might hibernate, and some plants shed their leaves and “hibernate” for winter in their own way.
What follows is a journey across the Pacific Slope to four favorite fall hikes–excellent for colorful foliage. I’ve also included some of the plant species that will be found.
Siskiyou Wilderness
Pasayten Wilderness
San Gabriel River National Monument
Blackrock-High Rock Desert National Conservation Area
