Monday, March 24, 2008

A SOD Story, attachment to "my" forest.

Not the loss of lawns, which I can easily get over. But Sudden Oak Death syndrome (SOD).

SOD is decimating “my” forest. This alien disease first appeared in Marin county—the county just south of me—in 1995, although some say it may have been here since the mid ‘80s. It is caused by the water mold disease called Phytophthora ramorum.

The devastation of the tan oak along this ridge is enormous. As I drive home, the last three miles of the forest reveal hundreds of small and large dead and dying trees—some as high as 30 feet. It looks like a botanical firebombing. The dead trees stand out because they don’t loose their dead leaves for years, if not a decade or more. These sentinels are possibly a harbinger of things to come. SOD is decimating “my” forest. 

(A list of potential native host plants is at the end of this blog.)

Already the California bay laurel on this property is looking pretty shaggy and there is die-back on some of the limbs. Tan oaks and California bay tress make up 80% of the trees surrounding my house. Some say “this may merely be one of nature’s ‘house cleanings,’ removing genetically weak or damaged trees and leaving the healthier, stronger ones to produce better, sturdier offspring.” Well, I’m looking at a dead 40-foot high by 50 wide dead tan oak tree just 40 feet from my office and it’s not a pretty picture. I keep telling myself it wouldn’t be so bad if the leaves would fall off so the tree doesn’t look so miserable. But I still resent the death of these trees. These trees may follow the way of the elms that once graced so many yards and streets and the chestnuts that once were the major forest tree in the Eastern woodlands. But I hate it when it’s happening in my forest.

There will be a cascading effect on plants and animals as these trees die in greater numbers. As an example, the acorn woodpecker makes good use of the nuts from this tree. Squirrels nest in it. More than 300 species of animals; including 170 species of birds, 80 or more mammals and 60 varieties of amphibians and reptiles, and more than 5,000 insects make a home out of the habitats provided by the coastal live oak and tan oak trees, according to Bill Tietje, a natural resources specialist with the University of California Cooperative Extension. An acre of oak woodlands can have 10 to 100 million individual invertebrates which help to digest the decomposing oak parts to recycle nutrients for new growth. In the words of John Muir, “When we try to pick out anything by itself, we find it hitched to everything else in the universe.”

The death of tan oaks has been a great struggle at learning how to be unattached to the flow of nature (and mankind for that matter.) Sometimes as I drive home I simply gaze in a way that seems to selectively block out the view of the brown-leaved ghosts of the oak. I use to return from a trip out of state or the country and wonder in amazement at why I went somewhere else when it’s so beautiful here. Now when I return, I’m shocked at the death in the forest that I’ve forgotten about when I traveled. The forest may not cry, but I do. 

The ecological changes that happen will be slow and I probably won’t see the recovery or replacement of this wonderful tree in my lifetime. So the tragedy seems so personal. I am only one piece of the ecology but a very selfish one that doesn’t want to witness the slow demise or partial downfall of this tree that was here long before me. I just can’t let go.

This is the list of those trees and plants known to be host plants for the disease in California.

Scientific Name Common Name(s)
N= Native, MH = Grows around my house.

Acer macrophyllum Bigleaf maple - N
Adiantum aleuticum Western maidenhair fern - N
Adiantum jordanii California maidenhair fern - N
Aesculus californica California buckeye - N, MH
Arbutus menziesii Madrone - N, MH
Arctostaphylos manzanita Manzanita - N. MH
Rhamnus californica California coffeeberry - N
Heteromeles arbutifolia Toyon - N
Lithocarpus densiflorus Tanoak – N, MH
Lonicera hispidula California honeysuckle – N, MH
Pseudotsuga menziesii var.
menziesii & all nursery
grown P. menziesii Douglas fir - N, MH
Quercus agrifolia Coast live oak - N, MH
Quercus chrysolepis Canyon live oak - N
Quercus kelloggii California black oak - N
Quercus parvula var. shrevei
& all nursery grown Q. parvula Shreve’s oak - N
Sequoia sempervirens Coast redwood - N, MH
Trientalis latifolia Western starflower - N
Umbellularia californica CA bay laurel, Oregon myrtle – N, MH
Vaccinium ovatum Evergreen huckleberry - N, MH

Please post a comment - I want to know what you think.

Note: I somehow lost the usual section "Post a comment". To leave a comment, simply click on the area/button that says "___ Comments". Clicking on the title of a Post under "Blog Archive" also gets you to a view that gives the option of leaving a comment. I hope to figure this out soon. Robert

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