Showing posts with label * fungal diseases. Show all posts
Showing posts with label * fungal diseases. Show all posts

Saturday, December 7, 2013

coast live oak ~ 12/07/13 ~ Fort Ord

Fagaceae

As we were driving out to the Creekside entrance on Hwy 68, I noticed most of the oaks had dead tips.  Speeding past, it looked like a deep green mosaic with scattered bits of tan.  I don't think this is sudden oak death, which is caused by a fungus-like pathogen.  I'm guessing it's caused by true fungal diseases, some of which apparently show themselves more when the oaks are drought-stressed, like this year.  I'm not quite sure how that works since fungi generally like moisture.  Right?  This looks very different from the swaths of entirely dead trees I saw last year at Toro Park, which is located right across the street of Hwy 68.  The U.S. Forest Service Pacific Southwest Research Station has an excellent technical report "A Field Guide to Insects and Diseases of California Oaks".  Maybe it's Diplodia quercina branch canker (pp. 88-89) or Cryptocline cinerescens twig blight (pp. 76-79)?  I really don't know.  I'm no tree doctor.  Half the time I can't even distinguish coast live oak from other Quercus spp.  In any case, this widespread dieback is interesting to note.

ps 03/12/14 - An intern from a local paper The Californian contacted me regarding this post.  She wants to use my pictures and information in an article she's writing.  This is the first time I've ever been contacted by a newspaper for Nature ID, so it was an interesting experience... I think for the both of us.  She was sweet but sounded a little nervous.  I gave my photos free of charge, because I didn't want the hassle of creating an invoice and dinging for payment (so many places conveniently "forget" to actually pay).  I'll link to the article once it comes out.  Cool beans.

Wednesday, July 18, 2012

tanbark oak ~ 07/18/12 ~ Mt. Madonna

posted 08/03/12 - When we last camped at Mt. Madonna in December 2010 I noticed great swaths of tanbark oaks had been recently chopped down. At the time I wasn't positive about the ID of this tree, nor did I hazard a guess as to why so many of these trees had been cut. Thanks to Randy at Way Points I learned more about Sudden Oak Death, which can affect tanbark oaks and Quercus spp. I suspected the clearing had to do with this disease, but I was wrong. As I looked into Santa Clara County Parks for this blog post, I discovered their best management practices included monitoring for pathogens such as Armillaria oak root rot fungi and others. What? It never occurred to me that mushrooms could kill trees. Clustered fruits, such as honey mushrooms (Armillaria mellea), may indicate the presence of deadly diseases. I now wonder about the ID of the possible sulfur tufts I found. Hmm, always learning something new.

Sunday, March 20, 2011

CA yerba santa ~ 03/20/11 ~ Fort Ord


California yerba santa
Eriodictyon californicum
Boraginaceae (formerly Hydrophyllaceae)

I've hiked past these always wondering what they are, most notably for the black fungus covering most of the leaves. You can see some black leaves in both pictures above. Wikipedia says this fungus is called Heterosporium californicum, but I can't find any online information other than this sooty fungus is common on this plant. This is the first time I've seen these shrubs blooming. It's really hard for me to believe that these are in the same Eriodictyon genus as the woolly yerba santa I spotted at Pinnacles recently. Erg. Once again this plant has changed families from the waterleaf family Hydrophyllaceae to the borage family. These family changes are harder to track than women who change their surnames due to marriage and/or divorce.