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The California Acorn Report
Vol. 3 28 Sept. 1999
The Newsletter of the Official California Acorn Counting Team: Walt Koenig and Jean Knops
Author/Editor:Walt Koenig (wicker@uclink4.berkeley.edu)
HELLO TO OUR MANY FANS OUT THERE IN ACORN LAND
Welcome yet again to the California acorn report! We know many of you have been eagerly awaiting the latest news on this, the last acorn crop of the millennium. And we will not disappoint you. However, as usual, we will make you wade through virtually this entire rag before you finally run across anything resembling data. Relax and enjoy!
FIRST TO THE GREAT MIDWEST
Oddly enough, the California acorn survey traditionally begins in Minnesota. Why Minnesota, the land of endless mosquitoes, deep-fried cheese curds, and minidonuts? Up until this year, Jean had a job there babysitting field assistants at Cedar Creek, a field station 30 miles north of Minneapolis. As a result, I started visiting several years ago and while I was there we figured we should count a few acorns. We now survey six sites differing in burn frequency, within which we count acorns on pin, bur, white, and red oaks. This was the fifth year for the Cedar Creek survey.
Cedar Creek happens
to be an LTER site, which basically means that NSF throws unbelievable
amounts of money at it hoping that people will do interesting things
there. Even though (or perhaps because) this year Jean left Cedar Creek
and moved to the University of Nebraska, Jean was able to tap into
this amazing source of wealth and obtain "additional funding" for
the acorn survey, Thus, we now have two (count them: one, two) official
sponsors of the California acorn survey: the California Fish and Game
(thanks once again to Barry Garrison, who orchestrated it all), and
the National Science Foundation. Not only are these official sponsors,
but we have decided this year to designate Cal Fish and Game and the
Official Department of Fish and Game and the National Science Foundation
as the Official Science Foundation of the California
Acorn Survey. Congratulations to both these organizations, and keep
up the good work! By the way, we expect several additional sponsorship
opportunities to open up in the near future; we're particularly interested
in recruiting an agency that rents Hummers. If you know of any that
have a side interest in the acorn crop, please let us know.
...WHERE WAS I?
Minnesota. Right. With Jean now training to become a Cornhusker in Lincoln, Nebraska, we both had to fly to Minneapolis to do the Cedar Creek survey, which we did over the weekend of 27-29 August. Unfortunately, Jean has all the data and since he now actually works for a living he hasn't had time to organize it all and so I can't actually tell you much about the crop, other than that there were acorns there. At least some. On one of the species; or was it two of them? Oh well. Perhaps we'll succeed in getting the data included in a late edition of the newsletter.
Otherwise, Minnesota was great, despite the everpresent bugs. Unfortunately I pooped out on Saturday and didn't make it to the State Fair, which is usually the unquestioned highlight of the trip. We might have gone on Sunday, but Jean was so adamantly allergic to the concept that he chose instead to drive out to Stillwater and have lunch with an old high school friend of mine and her husband. I guess those Dutch just aren't taught to crave minidonuts all their lives as were those of us who actually grew up in the Midwest.
THEN OUT TO CALIFORNIA
After but a brief interlude, Jean
reciprocated with his visit to California. This year, with a few extra
bucks to squander, we rented a full-size car ("The Boat")
for the trip, which was actually pretty nice for me since it was pretty
easy to sleep in and perhaps not so nice for Jean since he had to put
up with my snoring while driving. In any case, the good news is that
Jean wrote up the xylem water potential paper so we did not have
to totally wipe ourselves out the first couple of days by dragging
ourselves out of bed at 3 am to go blow up leaves. (Unfortunately,
the paper hasn't been accepted by anybody yet, so there's still
a chance we might get to do so again in the future...). The bad news
was that, with Jean coming over Labor Day weekend (the only week he
could get out of teaching those Cornhuskers) and with Bill Carmen having
just had knee surgery (we assume to remove the alien implants given
to him during prior acorn surveys), Bill wasn't able to join us for
the traditional gin and tonics up at Red House following the end of
the survey. Of course, one of the great things about the California
Acorn Survey, is that there's always next year.
In any case, this, the 20th anniversary Hastings acorn survey, was done on 2-4 September. This is earlier than in prior years, which made for a few disputes over whether acorns were "immature and on their way" or "little squirts that were going nowhere". On the other hand, we didn't have to contend with trees from which all the acorns had apparently already fallen or been removed. All in all, we decided that earlier is probably better than later.
THE STATEWIDE SURVEY
With Jean only here for one full week, we had little choice but to totally revamp our now well-established schedule. We apologize profusely for the many fans who usually line our route and who consequently missed us. If any of you are still out there, you can go home now, at least until next year. Don't forget to count a few acorns along the way back.
One advantage of doing the survey in one fell swoop, as opposed to in a northern and a southern route, as in past years, is that we didn't have to spend a lot of time hassling over which direction to turn on Carmel Valley Road which, as many of you will recall, has been a continuing hangup in prior surveys. So, bright and early at 5 am on 6 September, Jean and I headed out in The Boat and turned.....right, thus heading up toward Jasper Ridge. This year for once we remembered not to drive through Palo Alto and buy nostalgic (but overrated) sandwiches at the Cheese Shop, but rather headed for SF and the Pho Phu Quoc at 1816 Irving St. just off 19th avenue before Golden Gate Park. The lunch was excellent, and prompted us to consider designating the "PPQ" the official Vietnamese Restaurant of the California Acorn Counting Team. In the end, however, we decided to rate the restaurants we succeeded in visiting along the way for those of you who are trying to plan your 2000 vacations to retrace the legendary California Acorn Counting Route. At 5 or 6 restaurants per year, we figure we should have the majority of serious California eating establishments covered by about 2315, so stay tuned. The scale is 1 to 5 acorns.
BACK TO THE CHASE
This was an exciting year for the California Acorn Survey. Forced to circle the state in a single sweep, we made the audaciously optimistic gesture of adding two sites, one species, and several additional populations to the survey. In particular, we are pleased to announce that Kaweah Oaks and the Kaweah River Ecological Preserve have now joined the California Acorn Survey's family of acorn-counting sites. We are equally pleased to welcome our very own Interior Live Oak (Quercus wislizenii) to the California Acorn Survey's family of species. For the first time, this provides at least some data from the southern end of the Sierras and from this third species of live oak widespread throughout the state. While we were at it, we figured we would add a few new populations at sites we were already covering. Additions included:
Hopland (Mendocino
Co.) Valley Oak
Sierra Foothills (Yuba Co.) Interior Live Oak
San Joaquin Exp. Stn. (Madera Co.) Interior Live Oak
Kaweah Oaks (Tulare Co.) Valley Oak
Kaweah River Ecol. Reserve (Tulare Co.)
Canyon Live Oak
Blue Oak
Liebre Mtn. (Los Angeles Co.) Valley Oak
Kaweah Oaks is one of the last remnant Valley Oak forests left in the central valley and was a logical place to stop as we shored up our otherwise fairly sparse Valley Oak sites. Kaweah River Ecological Reserve took a bit of searching; despite the directions in the usually reliable Oaks of California we drove right past it and marked 10 trees along somebody's driveway before we eventually discovered the reserve above (not below) the road. In any case, the addition of these populations brings the total number of species covered by the survey to 7, the total number of sites 16, the total number of populations surveyed 41, and the total number of individual trees 958, The survey now covers all tree species in California except for the island oak (we still haven't figured out any way to make it out to Santa Cruz Island efficiently), the Shreve oak (which I didn't even know existed until now), and, of course, the tanbark oak, which we really should survey somewhere even if it isn't a damn Quercus.
Blue oak sites now included in the statewide survey
In the end, we covered 2,105 miles in 6 days, collapsing in a heap back at Hastings on the afternoon of 11 September, just in time for Jean to head back home early on the 12th. If anyone figures out a way to shrink the state for a week in early September every year, let us know.
COUNTING ACORNS, AND A HISTORICAL DIGRESSION
Much to my surprise,
the hints I dropped in last year's newsletter concerning how we actually
count acorns on all those 900+ trees simply whet the appetite of our
readers as to the logistics of the California Acorn Survey. So, here's
what we do, really. When we set up a site, we mark trees that will
be relatively easy to find again, either with an aluminum tag or with
directions ("30m w of road next to large rock") written on
our survey sheet. At each site, we survey 20 or so trees of each species
surveyed at the site, except in a few cases, where we go down to as
few as 10 trees or (in the case of Hastings) up to as many as 86. (As
it happens, we have reason to believe that even a very small sample
of trees surveyed over a long period of time will yield a ranking of
the years that is as accurate as a large number of trees sampled over
the same period.) 
Jean exhibits his award-winning form while counting those rare, elusive Engleman oak acorns on the Santa Rosa Plateau.
Each year we then go to the same individual trees and, usually with binoculars, count as many acorns on different parts of the tree as we can in 15 seconds. This yields a value (acorns counted in 30 s = N30) that provides a fairly good index as to the acorn crop of the tree, and works well statistically, especially after log transformation. It's not perfect; in particular, lighting and foliage can be a problem and the measure is fairly insensitive to differences between trees that have lots of acorns and those that have lots and lots of acorns. However, it's fast, efficient, and probably more accurate than any viable alternative, including traps, which are used a lot in the East but don't work particularly well here in the West where there are still a lot of predators like jays and woodpeckers that remove acorns directly from the canopy before they have a chance to fall to the ground. This sort of "visual survey" is also the only feasible way of measuring lots of trees over a wide area in the relatively brief length of time that is available.
This method is modified from one presented at the original oak symposium in Claremont back in 1979 by Walter C. Graves, at the time a Wildlife Biologist working for the California Department of Fish and Game in Chico. Graves, who has since passed on to that great oak savanna in the sky, was ahead of his time in that he envisioned a series of sites throughout the state at which Wildlife Biologists would survey acorn production. In his symposium report, for example, he presents information on acorn production by 9 species of oaks in 19 counties over 3 years, 1976 to 1978. Unfortunately, individual workers were apparently not always particularly fastidious about what species they were surveying or when they performed the survey and little has emerged from this inspired attempt at surveying acorn production on a statewide scale, although remnants of it are still conducted. Nonetheless, we owe a considerable debt to Graves, the California Department of Fish and Game, and the Integrated Hardwoods Range Management Program, all of whom played, and indeed continue to play, an important role in today's New Revised California Acorn Survey.
We were barely prepared for the busloads of tourists that came to watch us count acorns in Yosemite Valley. How were we to know we had become international celebrities?
...AND THE COUNT IS?
In order to see into the minds of the California Acorn Counting Team, you will need to imagine yourself back at Hastings in April. The weather was wretched. It was cold, foggy, and generally dismal day after day. Mean temperatures were the lowest since 1983. It short, it sucked.
As a result, I had sort of figured it would be a bad acorn year, at least for blue and valley oaks. This follows from the excellent relationship we've had (up until now, at any rate) between mean April temperature and the subsequent acorn crop, as per the following graph:
So what can I say? It was a much better year than I had expected. In fact, it was really quite good for blue oaks up and down the state; all sites surveyed were well above the overall averages recorded since the survey was initiated. Valley oaks were not as good but were average or above average at all sites.
Our expectations didn't prove more successful with the other species either. Coast live oaks have previously correlated well with rainfall from two years previously (rainfall lagged one year), but the crop in 1999 was considerably lower than we expected given the El Niño floods of 1997-98:
Again, this pattern held true elsewhere as well. Crops of both canyon live oak and California black oak were generally about average compared to prior years. Even up on Liebre Mountain, where the black oak acorns often seem to be everywhere, the crop was relatively mediocre.
So there you have
it. Once again, the crop fooled us in terms of the proximate cues trees
use to determine what to do. You'd think that after 20 years at this
we'd have figured it all out, but hey, nobody ever said this was going
to be easy. At least there's an excuse to keep at it for a couple more
years at least. Who knows? Maybe one of these days we'll actually figure
out what the heck's going on out there!
The official exotic mammal of the California Acorn Survey team tends his herd at Hopland.
SCIENTIFIC PROGRESS
I know it seems almost unbelievable, but in between the annual acorn survey Jean and I actually do other things, like (try to) write papers. Since last year's newsletter, we've reported on synchrony in acorn production in the central coast, focusing primarily on the Hastings, Jasper Ridge, and Pozo data as well as a transect we did for several years between Hastings and Paso Robles (Spatial dynamics in the absence of dispersal: acorn production by oaks in central coastal California, Ecography [in press]), synchrony between acorn production at Hastings and Hopland (combining our data with that of Dale McCullough's from Hopland going back to 1982)(Synchrony and asynchrony of acorn production at two coastal California sites, Madroño 46: 20-24, 1999), large-scale synchrony and asynchrony between seed production and tree-ring growth of boreal trees (Scale of mast-seeding and tree-ring growth, Nature 396: 225-226, 1998), general masting patterns and their relationship to variability in weather (Patterns of annual seed production by Northern hemisphere trees: a global perspective, Amer. Natur. [in press]), and the relationship between acorn production, oak species diversity, and acorn woodpecker distributional ecology (Oaks acorns, and the geographical ecology of acorn woodpeckers, J. of Biogeography 26: 159-165, 1999). I got really lucky with the latter as it was written up in a News and Views in Nature in June (Woodpecker population drills, Nature 399: 528-529, 1999). As always, stay tuned for the latest in cutting edge acorn production literature satirized here in The California Acorn Report.
THE CALIFORNIA
ACORN REPORT REACHES
100 MILLION SUBSCRIBERS!
Well, not exactly. But as you can see from the graph, the trajectory from the past three years (during which time the subscriber base has risen from 1 to 25 or so) clearly demonstrates that shortly after 2005 we can expect somewhere close to 100 million eager recipients. Unfortunately, this will require felling a substantial fraction of the world's boreal forests in order to provide paper, a dedicated KINKO's for photocopying the newsletter, a full-time staff of 50 to stuff envelopes, and somewhere around a $48,001,000 budget ($33,000,000 for stamps, $15,000,000 for paper, supplies, and photocopying, and $1,000 for the survey itself).
<www.hastingsreserve.org> and click on "Resources for teachers" at the bottom on the left side.
So keep in touch! We of course would like to hear from you regarding your questions and experiences regarding the California acorn crop. See you next year, and, as always, live long and keep counting those acorns.
How do we stay so fit and trim in the field? It's incredible, I know. Stay tuned to the California Acorn Report where we will have a special section next year on "Fashion tips from the California Acorn Counting Team".
You can contact the California Acorn Survey Team at either of our international offices:
Hastings Reservation,
38601 E. Carmel Valley Rd.
Carmel Valley, CA 93924 (831-659-5981)
or
School of Biological Sciences, University of Nebraska
348 Manter Hall, Lincoln, NE 68588-0118 (402-472-6449)
There is only a moderate grain of truth to the rumor that we are planning to go public within the next year.