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

coast live oak / California live oak

Quercus agrifolia var. agrifolia

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.

CA oak moth ~ 09/23/12 ~ Toro Park

California oak moth caterpillar / California oakworm on coast live oak or interior live oak
Phryganidia californica on Quercus agrifolia var. agrifolia or Quercus wislizeni
Fagaceae

Coming down through Wildcat Canyon, I found great swaths of dead-looking oaks, yellowish brown and upon closer inspection severely munched upon by oak moth caterpillars.  I don't think the folks who named the canyon had this kind of wild cat in mind.

Sounds of drops like gentle rain and tinkly crunchy chomping surrounded me.  The smell in this area was distinctive, too, but I can't easily describe it.  The trail and nearby ground were completely coated in greenish tan pellets.  Frass.  Caterpillar poop. And lots of it! The most I've ever seen... which really doesn't mean much considering I don't follow the fluctuating annual cycles of oak moth populations all that closely.  I believe there are people who use frass mass to estimate population densities, so my assertion isn't totally out of the blue.  This past spring, I did casually notice oak moths were on the wing in full force unusually early on with a second generation flying in June or July.  Unfortunately, I didn't take notes of the timing and my recollection isn't specific, only that it was significant enough that I commented to a couple of Monterey City forestry fellows at the local farmers' market how I predicted this was going to be a booming oak moth year.  They laughed me off and politely disagreed.

The few green leaves I found here had become veritable buffet lines for caterpillars. What surprised me was finding so many feeding on dead leaves. Their mandibles have got to be industrial strength to masticate crispy dried evergreen oak leaves.  There were plenty of dead caterpillars that simply looked dessicated, but there were also numerous dead caterpillars hanging by their first prolegs, a sure sign of a viral and/or bacterial infection.  Interestingly, I did not find a single chrysalis (yes, I use this term for moth pupa in addition to butterfly pupa, if it's not covered in hairs or silk and hangs by a stalk).  I wonder if this 3rd seasonal generation will successfully pupate and emerge in the next few weeks, or if this is an early sign of a natural population crash.

Even when everything else is dried up, live oaks usually remain green all year round.  I doubt the caterpillars were directly responsible for the dried oaks, because I suspect their heavy feeding did not actually kill the trees.  Our unusually mild winter with very little rain was gentle on last year's overwintering early instar caterpillars and also water stressed the oaks.  However, there were numerous other oaks in the park that were still green and with significant numbers of oak moth caterpillars.  There is a part of me that wonders if this area, easily accessible to group picnickers, had been hit by Sudden Oak Death or an Armillaria oak root rot fungi.  I will be curious to find out if these oaks have a fresh flush of green leaves after the rains hit.

I blogged about CA oak moths once before, which is an unexpectedly popular post.  I've linked to the UC IPM Online site for CA oakworms in the scientific name ID above, and I don't recall why I didn't include it in my previous oak moth post since it's chock full of great information. Also, while doing another oak moth search, I found this fellow blogger Garden Wise Guy's post to be quite entertaining.

ps 09/26/12 - Thanks to Cindy at Dipper Ranch who commented and always gets me thinking about things.  I have such a difficult time IDing trees, let alone the confusing complex of oaks. I've edited the post above to include the possibility that the oaks I saw were interior live oaks and the possibility the browned leaves were due to an oak root rot fungi.  I'll see what I can do about contacting the proper agencies to check into this, because SOD is closely monitored.

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

tanbark oak
Notholithocarpus densiflorus
Fagaceae

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.

curly dock ~ 02/20/12 ~ Pinnacles

curly dock
Rumex crispus
Polygonaceae

I was a little disappointed to see this weed at Pinnacles, a place I consider relatively pristine. To my knowledge, Pinnacles has never been farmed or used for any other purpose than pure enjoyment. I wonder how much hikers inadvertently bring in weedy seeds or spores on their shoes, clothing, and camping gear.

At the research reserve in Elkhorn Slough, they require every visitor to step into bleach water with hopes to keep out Sudden Oak Death (SOD). I don't mind at all. Hehe, this reminds me of the time our camping gear was held for several days at the Auckland airport upon arrival in New Zealand. Andy didn't have a lick of spare clothing, and we were in Tairua by the time an airport shuttle finally delivered his backpack. It wasn't all bad; he got a now-favorite holiday shirt from a second-hand store along with some swim trunks, and we stayed in a lovely cabin since we couldn't camp.

ps 09/13/14 - It's been interesting reading through my older posts.  I have to say, now that I know the lovely great copper butterfly uses dock as a host plant,  I very much like seeing this very distinctive reddish plant around.  I'm amazed at how I was getting caught up in the biological xenophobia that's been going around.  I don't want to be in the mind frame that it's okay to kill things and be super distructo simply because, today, I deem it somehow to be bad.  Tomorrow, I may change my mind and deem it be good (as shown here), but then it's too late.  And, also during a recent visit to the Park, I talked with a couple historical researchers who told me that a part of the property was once a copper mine claim.  They'll have that information available in the next year on the website.  Cool.  Also, I'm trying to make it a habit to clean my hiking shoes and gear before I leave a place, so that I can minimize anything I might potentially spread at my next hiking destination.

CA bay ~ 11/19/11 ~ Garland Ranch

California bay / Oregon myrtle
Umbellularia californica
Lauraceae

After a full year of thinking about it and posting about it back in July, I finally had my first taste of a California bay nut. Well, actually, being the piglet I am and wanting to compare, I tried 3 bay nuts. I was so excited I didn't get a picture of the first one, but it was reddish and squishy like the first photo above. The flesh had the texture and taste that reminded me of a cross between a firm avocado and an unripe mango, mild, slightly sweet, and with only a hint of bay. The second one I tried was a bit greener yet also soft. I barely nibbled it before I spat it out. It had a very, very strong bay flavor. It left a burning tingle in the back of my throat, similar to the effect I get when I eat fresh mangoes - I've already looked it up, CA bays are related to avocados but not mangoes. Hoping to try another ripe bay nut, I ate a third that was somewhere in between. Had I been prudent, I would have simply saved them and waited until I got home to taste them; for the rest of my hike, my throat tingled and every exhale tasted like bay. My stomach was not a happy camper by the time I finished my hike.

Interesting to note the seed of the first ripe one was very dark, whereas the seed of the second green one was a much lighter color. In the third photo I also want to show there are buds on the evergreen CA bay already. And the last picture shows a very large and mature CA bay tree.

ps 02/06/12 - I initially posted the last picture believing the large tree was an oak (Quercus sp.) next to a smaller CA bay. The significance of this is that the CA bay serves as a host to a pathogen that causes Sudden Oak Death, which also affects tanbark oaks (Notholithocarpus densiflorus). For a very informative blog post about SOD, check out Randy at Way Points. I'm always amazed at the things I learn from fellow bloggers. During another hike at Garzas Creek on 01/16/12, I took a second look at the large tree and realized I had been mistaken about its ID. I've still got a lot to learn about trees.