no till and soil improvement
- To: m*@ucdavis.edu
- Subject: no till and soil improvement
- From: M* B*
- Date: Sat, 18 Dec 1999 15:59:03 -0700
The Ryans wrote, " Strangely, and against all received wisdom and
common sense both individual observations and formal experiments disagree
with you in this." "This" being Richard Starkeson's recommendation to in-
corporate compost and wood chips and mulch into the top six-twelve inches of
airless sticky clay. They continue, "Field trials (snip) a few years ago
were done to find out which was the best way to incorporate organic matter
(compost) in(to) soils. They compared conventional ploughing, rototilling
and simply applying the compost to the surface. They found that the
surface application was in fact the most effective and the ploughing the
least (!).
I'm no scientist but we bought our double lot high in the Berkeley
Hills in Aug. 1968. It consisted of one hillside covered with Vinca major
(boo!!!), the entire front garden was a good strain of English ivy (Hedera
helix) and the main garden was a huge nest of Pittosporum undulatum from
seedlings to 25 foot trees with as much as 32" circumference at 36" from the
soil. Soil (ha,ha & ha!)---greenish grey sticky clay no matter how deep
you dug. Airless, dense, incredibly heavy---glue in the winter and a bit
like Miss Havesham's face in the summer. From 1968 to 1974 I spent about
$ 6,000.00 on soil amendments: redwood sawdust, pine chips, homemade com-
post, oak leaf mold (screened), crushed lava, SuperSoil. Some of it
worked for one, even two seasons but when you wanted to plant a shrub in
an area of amended garden it was solid clay.
Finally in 1977 I heard about no-till at the Cal Chapter of the
American Rhododendron Society in a talk by the Evanses. I had 50 cu yds of
Clark's mix (G-d alone knows what was in it) poured in my driveway and my
first wife and I spent the next four months bucketing it up the hill and
putting down a layer a full 12" or more thick over newspaper over the
entire garden. We waited a year and then began to sample. In a very few
places
I now had a smelly sandy loam like the English dream of, other areas were
less successful. We grew annual rye grass and dug it into the mulch that
Spring, 18 mos. after delivery and by then I had designed a new hardier
garden---no more palms and hibiscus, no more melastomaceous ground covers.
I still try to dig a substantial hole---you remember the old saw we were
taught---a $ .50 plant in a $ 5.00 hole and amend the hole to what I think
each plant needs. Sometimes, when it's a xerophyte I fill the hole with
80% granite chippings and 20% light weight compost. Rhododendrons are
planted above the soil. Roses get 50% clay and 50% leaf mold. You may
extrapolate from here.
Every second or third year I mulch with 6" of 1/4" fir bark clean
(that is dust free) and in autumn all calciphile plants get a good sprinkling
of tomato and vegetable food, all calcifuge get several cups of cottonseed
meal and then I mulch lightly.
TROTS. About 40% of my garden now has friable soil of good tilth.
The woodland failed completely because of lack of sun so we dug out and
gave away 16 cu yds of "fill" and created raised beds underground and still
we plant on top of this area when it comes to rhododendrons. We're generous
with water and free manures, etc. It does not work completely but it sure
beats breaking your back year after year only to have amended soils return
to the state of anaerobic clays. Maybe by the time I die 75% of the real
soil will have "converted" but this method is certainly superior to amend
and till and if it weren't for the Otorrynchus sulcatus weevils I'd let the
fallen leaves under rhodies stay there. I don't remove any fallen pine needles
from my neighbor's Pinus radiata and I hide dying perennial foliage under
the mulch.
Best holidays to all, this has been the most difficult year of my
life and shall be thrilled to say goodbye and good riddance,
SKOL
Michael D. Barclay
Really Special Plants & Gardens, Kensington, CA
Cal Hort Council opga@wenet.net Growing 2,000 species of plants
15 miles from the Golden Gate. ARS Speakers Bureau lecturer.
