Hello ENTS,
earlier this month I visited my brother and his family in Pasadena, California
and I was able see some cool trees. I especially focused on oaks because I
really like them and California is blessed with quite a few species. They have
a total of twenty species and nine of these get to be tree-size. Four of these
belong to the subgenus Lepidobalanus or the White Oaks. These include valley
oak (Quercus lobata), blue oak (Q. douglasii), Engelmann oak (Q. engelmannii)
and Oregon oak (Q. garryana). Three species belong to the subgenus
Erythrobalanus or the Red Oaks. These include black oak (Q. kelloggii), coast
live oak (Q. agrifolia) and interior live oak (Q. wislizenii). These two
groups are very familiar to us in the East, but then there is a third group in
California as well; these are the Intermediate Oaks in the subgenus
Protobalanus. Canyon oak (Q. chrysolepis) and island oak (Q. tomentella)
belong to this group which, as the common name implies,
is intermediate between the White and Red Oaks.
I made almost no measurements so this will mostly be some pictures with
descriptions. I think I'll start with canyon oak because it was the first
species that we really encountered in good numbers on this trip. It is the
only species in the Intermediate Oak Group that we encountered. We started our
California trip by going from Pasadena to San Diego to see the city, the zoo
and a friend that Ellen had not seen since high school. From there we went
East to Cuyamaca Rancho State Park to spend the night.
Image #1 This is a closeup of the leaves and acorns of canyon oak. According
to the authors of "Oaks of California", this species "probably has the largest
acorns of any North American Quercus, especially if trees from coastal hardwood
forests are measured." The acorns are certainly large but I think that the bur
oaks of the southern states, especially Texas, probably have larger acorns.
The leaves are shiny and bright green above but dull and more bluish or grayish
below with many tiny golden or silvery hairs. The golden color extends to the
acorn scales and this is why this species is also known as goldencup oak. The
scientific name of chrysolepis, which means gold scale, also refers to this
particular characteristic.
Image #2 Cuyamaca Rancho State Park was mostly recovering from a relatively
recent fire. In fact we later learned that it had burned twice in the last few
years. This image shows several canyon oaks that burned but they were
resprouting...I think from the roots? In some areas where the fire was not as
intense, I guess, the trees were able to resprout from the trunk and limbs.
Some were able to resprout almost all the way to the top! The leaves of this
species can be either smooth or spiky. On old trees the leaves are mostly
smooth but leaves from trees that are resprouting are mostly spiky. This image
was taken while we were hiking up Stonewall Peak.
Image #3 After leaving Cuyamaca Rancho State Park we went to Palomar Mountain
State Park. There were some burned areas here as well but they were not nearly
as extensive as at Cuyamaca. This tree was an especially nice one located next
to an Employee Residence at the campground. It was 15.5' in girth.
Image #4 A closeup of the trunk of the same tree showing the fairly smooth
bark.
Image #5 Looking up the trunk of the same tree.
Image #6 Another nice tree next to a bunch of boulders. This species often
seems to be growing among boulders.
Image #7 This is still in Palomar Mountain State Park at the campground within
site of the previous two trees. This tree was 17.4' in girth. A nearby tall
canyon oak made it into the low 80's in height.
More California oaks to come in the future.
Doug
--
Eastern Native Tree Society http://www.nativetreesociety.org
Send email to [email protected]
Visit this group at http://groups.google.com/group/entstrees?hl=en
To unsubscribe send email to [email protected]
