by Laurie Meadows
significantly smaller pinenut tree that bears very large cones
with large pinenuts of nutrional value second only to Pinus pinea. It is probably
tolerant of a wide variety of soil conditions, as long as
drainage is good. Time from seedling or cutting to first cones
is unknown. It is no longer available in New Zealand. It is
possible to graft this species to a Pinus pinea rootstock, or may even find a use
as a possible size-reducing rootstock for Pinus pinea, although this
This is a rare pine nut species
found only on an isolated Mesa in the wilds of Mexico
(recently another small population has been found). It was
first discovered in 1964.The common name is Martínez piñon
('pinyon'), and increasingly commonly 'maxipiñon'.
The cones are very large, and the seeds are also very
large (about 6 grams each, fresh weight), although the seeds
have a very thick shell. Apart from size, the
seeds are remarkable for their high protein content - around
30%, second only to Pinus
pinea, one of the major 'pine nuts' of commerce.
Some time around 2005-2007 (at a guess), I bought four
cutting-grown plants from Cedar Lodge nurseries in Taranaki.
I have always assumed they are all from the same tree, and
therefore identical to each other genetically.
They have grown here quite well, (they are about 4 metres
tall and wide), and all four trees developed their first
ever male flowers in the spring of 2013. So far, I haven't
found any information to say whether or not they are self
fertile. My working hypothesis is that they aren't, and I am
going to need an unrelated tree to cross pollinize with.
The trees are now more or less globe shaped, and somewhat
open. I trimmed some side branches that were in the way,
which was a mistake, as these have mostly died back.
Apparently this species does have dormant buds under the
bark (epicormic buds), but these may not be triggered unless
there is major damage to the trunk. Update April 2012
- 3 out of the 4 trees here have a few tiny shoots growing
low on the trunk. I assume these are from epicormic buds.
In autumn 2012 I
grafted some wood of P. maximartinezii into Pinus pinea. There was
a brief reference on the internet from an Australian pine
grower saying that the species are graft compatible,
although the union is very rough. This success with grafting
maximartinezii onto P. pinea opened the way to grafting an
unrelated P. maximartinezii scion onto both the
trees in the ground, and a couple of trees destined for
growing in tubs.
There are unrelated trees in New Zealand. Cedar Lodge no
longer sell P. maximartinezii
(and were not long ago appealing for seed sources for some
of the rarer conifers that had been introduced to New
Zealand prior to the new additional MAF
controls put in place in mid 2002 to mitigate the risk
of bring in the devastating pitch pine canker disease, Fusarium
Trees were available from at least one New Zealand nursery
in the mid 1980's. Seed was also distributed by the late Loy
Shreve, (Texas Cooperative Extension
Forestry specialist) in the mid 1990's.
Dow Seeds Ltd listed
Pinus maximartinezii in their 2000-2001 seed
catalogue, and it was not marked as a 'new item' at that
date, so it has been offered for some time before then
($78.40 for 50 grams of seed, about 8 seeds - that's $9.80 a
months on (30 march 2013), and the scion has made some good
growth. The stock has just been cut back. The tips of all
the lower Pinus pinea stock side branches have been
cut back repeatedly to encourage the maxipinon to become
dominant. This has caused the stock to produce short-leaved,
blue-green juvenile foliage.
Some scions from unrelated trees were finally obtained in
summer 2013. Some of these grafts into the trees in the
ground here look promising as at mid june 2013 (in spite of
the 2013 drought). Scions obtained
and grafted in autumn
(from a different source) all failed.
Unexplained graft union failure some years after grafting is
a recognised phenomenon in pines. Just because maxipinon
grows successfully when grafted to a different pine species
does not guarantee the graft won't fail by five years time.
One paper, concluded that (in the 5-leaf
pines tested) compatible grafts (those that grow well and
survive long term) "usually" formed smooth graft unions, and
no "abnormal" swellings occurred at the graft.
Semi-compatible rootstocks also formed good graft unions,
and grew well for 5 or more years, but gradually showed
swelling at the graft union and "weakened" growth rates.
However, they also started flowering heavily around this
Semi - incompatible rootstock-scion combinations grew
weakly, and generally failed at or soon after 5 years.
However, the odd individual plant was the exception to the
rule, surviving well long term.
The grafting technique used by the authors of the 1972 paper
was a "side slit" graft on the terminal branch of the
rootstock. I first used side veneer grafts, but these tend
to lift, and more lately have used simple wedge grafts on
the terminal shoot. Wedge grafting might result in a rougher
graft union no matter how compatible the stock and scion. I
have tried a couple of whip and tongue grafts, but these
have failed, as have my few attempts at the "side slit"
Pinus maximartinezii appears, so far, to be
'provisionally' graft compatible with P. pinea and P.
armandii. Given P. armandii appears
compatible, the similar Eurasian Strobus species P.
siberica, P. koraiensis, and P. cembra
should also be tried. Pinus mugho is also know to be
compatible with many 5 leaf pines (a single graft on P.
mugho has survived so far - P. mugho is a very
small shrubby pine, so may ultimately be unsuited as a
Pinus pinea is an attractive proposition as a
rootstock due to its wide adaptation to various soils, and
its drought resistance.
Very little is published on rootstock compatibility, so much
is trial and error, and results are a very long time coming.
Ideally, this tree would be grown on its own roots, either
as seedlings, or cuttings.
My attempts to grow trees from cutting have failed; albeit
one cutting produced a few fine brown roots, but in the end,
did not establish. A few attempts at marcots have so far
Pinus armandii has proved to be graft
P. maximartinezii, but if it will endure in the long
run is as yet unknown. (Several grafted plants on this
combination have died, but further investigation showed the
rootstock had died from root rot, possibly Phytopthora.
Left: maxipiñon grafted onto P.
armandii seedling stock. The large mushroom that
appeared in the pot is probably the burgundy mushroom, Stropharia
rugoso-annulata. I bought inoculum some years ago, and
while they seemed to have died out, the last few years has
seen their return - probably due to my increasing use of
fresh woody mulch (which I have also put on top of the pots
of grafted maxi).
It is not a mycorrhizal species, so doesn't help the pine,
but it doesn't seem to have done any harm. Some reports
claim it 'boosts' soil fertility. Maybe, maybe not. But
young fruiting bodies of this species are edible (it
'fruits' in summer, after rain). And growing in a plant pot
has the advantage of protecting it from marauding hedgehogs,
which normally eat the fruiting body before or soon after it
emerges through the wood chips.
Experiments with a few stocks of other Pinus species
show greater or lesser promise, but my success rate with any
species remains dismally low. It is of no comfort that one
of New Zealand's most experienced and skilled conifer
grafters has yet to succeed with this species.
Much remains to be learned.
 Ahlgren, C E 1972. 'Some effects of
inter-and intraspecific grafting on growth and flowering of
some five-needle pines'
Silvae Genetica, 21, 3-4 1972
first published 2012, minor