[PCA] NEWS: Acorn Watchers Wonder What Happened to Crop

Craig Dremann craig at astreet.com
Mon Dec 1 11:52:43 CST 2008


Dear All,

I own a seed business, and in 1972-1980 we collected tree seeds for
nurseries, including all of the species of oaks in central California.
We used to have consistent acorn crops every year, until 1975.  I could
harvest 200 pounds from a single tree of Quercus lobata, for example.

We have two groups of oaks, the deciduous and the evergreen.  Q. lobata,
Q. kelloggii,  and Q. douglasii fall into the deciduous, and Q.
agrifolia and Q. durata fall into the evergreen group.

Probably all of the oaks above the Mason-Dixon line are deciduous and
below are mostly evergreen, like the Q. virginiana.

What appeared to be happening to our California oaks, is that the
flowers are being hit in spring by acid rain, which I have measured at
around 4.7 pH, and then the acorns do not form.

The only time they are forming, is during the current severe drought
<http://www.drought.unl.edu/dm/monitor.html>, when we have little or no
rainfall during oak flowering period.   The deciduous oaks are much more
sensitive than the evergreen species, and for the deciduous species,
there has not been a good crop for 20 years, or at least not until this
last year of severe drought.

The paradox of the California oaks only able to produce an acorn crop
during an extreme drought year, is that the ground is then too dry for
the oak seedlings to survive, which is what I have seen on my own
property.

Plus there are exotic animals in our forest, like introduced turkeys,
and wild pigs, that feed on any acorn crop that is produced.

During the Reagan era in 1983, I submitted a petition to list the three
most common deciduous species of California oaks, when I saw that they
were no longer producing any acorn crops, and you can still read in the
Federal Register, my 90-day rejection from that administration.

If acid rain or other factors are keeping our North American forest
trees from reproducing, we need to get them listed, at least as
Threatened, so that efforts can be made to recover the non-reproducing
species.

Sincerely, Craig Dremann, Redwood City (650) 325-7333





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