More Grafting

Wallowa Mountains (Circled)

Chief Joseph

We purchased potted Pinus sylvestris rootstocks to graft two-needle cultivars of P. thunbergii, P. mugo, P. sylvestris and P. densiflora. For Pinus contorta var. latifolia cultivars we used to also use P. sylvestris, but we switched to P. contorta var. latifolia* as rootstock about 10 years ago and our results improved considerably. The nurseryman must pay attention to the varieties or subspecies of his rootstock; the differences matter. For example, one could use P. contorta var. contorta to graft 'Chief Joseph', but var. latifolia is the mountain version of the species, and is much more winter hardy versus var. contorta which is known as the “Beach pine.” Surprisingly the usually reliable Hillier Manual of Trees and Shrubs (2019) blunders inexplicably on the issue by stating that the Beach pine “is a vigorous species used for fixing sand dunes in maritime areas. Introduced in 1831 by David Douglas.” Then 'Chief Joseph' is included as a cultivar of var. contorta which it certainly is not. Hillier is correct that 'Chief Joseph' was “discovered in the Wallowa Mountains, Oregon USA by Doug Wills [sic] and named after the famous leader of the Native American Nez Perce tribe of the Wallowa Valley.” The late Doug Will – not Wills – found the pine and I include an Oregon map (above) to aid the English reader, demonstrating that the Wallowa Mountains are far away from any beach.

Pinus contorta var. latifolia

*Pinus contorta var. latifolia, the “Lodgepole pine,” was discovered about 1853 by John Jeffrey, about 20 years after Douglas introduced the type species. “Latifolia” is Latin for “broad-leaved,” while “angustifolia” refers to “narrow-leaved.” For what it's worth, at Buchholz Nursery the needles of var. latifolia, or at least the cultivars we grow, are actually thinner than those of var. contorta. Of course it's too late to improve the scientific designation...even though it's not a very good one. There are two additional “Lodgepole pine” varieties: P.c. var. murrayana (“Sierra Lodgepole pine”) and P.c. var. bolanderi (“Mendocino Lodgepole pine”).

Pinus contorta grafts

The P.c. var. latifolia are prepared for grafting by removing the lower needles and all side branches, leaving a single, naked shaft. We want all extra, unnecessary foliage out of the way so that the grafted cultivars receive adequate air and light, especially in spring when both the rootstock and scions begin to push new growth. The grafting manager or owner decides what cultivars to produce, but many times the desired numbers are limited due to a lack of quality scionwood. The schedule may appear as this:

100 Pinus contorta var. latifolia 'Taylor's Sunburst'

All Pinus contorta var. latifolia 'Frisian Gold'

All Pinus contorta var. latifolia 'Willow Creek'

Finish with Pinus contorta var. latifolia 'Chief Joseph'

The scion cutter, in our case new employee Jordan, begins with “all,” which means all the scions possible without ruining the stock tree(s). If too many of the good shoots are harvested then you risk sustainability for future years. After the “alls” are completed and the quantities known, plus the 100 rootstocks reserved for 'Taylor's Sunburst', whatever number is left will be “finished” with 'Chief Joseph'. Of course I preview the scion locations with Jordan and show him the length and caliper that's ideal for each variety, plus I estimate the quantity that he “should” be able to find.

Pinus contorta 'Frisian Gold'

Pinus contorta 'Frisian Gold'

Pinus 'Frisian Gold' is a wonderful conifer that lights up the dreary garden in winter. It's not quite as intense for vibrant color as compared to 'Chief Joseph', but then it's not susceptible to the late-winter needle burn of 'Chief Joseph'. If planted in shade the color will also be more mellow, which is true for all cultivars of golden pine, whatever the species. 'Frisian Gold' originated as a witch's broom mutation at Jeddeloh Nursery in northern Germany near Oldenburg, an area in Lower (northern) Saxony called Friesland.* Jeddeloh (pronounced yed-de-low) is one of the largest nurseries in Europe, and well-known for other introductions such as Acer palmatum 'Jeddeloh Orange' and Tsuga canadensis 'Jeddeloh'. The original mutation of 'Frisian Gold' is sited in their display garden, and it's interesting that they have chosen to keep the green host tree still attached. It's a notable lesson as to the origin of certain cultivars that impresses the novice as well as the seasoned conifer collector. In ten years 'Frisian Gold' will grow about 2' tall by 3' wide at Buchholz Nursery in Oregon.

*Named for the Frisii, a migrating German tribe that settled along the North Sea. The land is mostly grassland with numerous lakes, and the locals are engaged with agriculture and raising cattle. They are considered “simple” by other Germans, especially concerning the Frisii located in northern Netherlands. The Frisii are mocked similar to the way Americans view our hillbillies from Appalachia. One arrogant German informed me that the Frisii have windshield wipers on the inside of their cars because the rustics tend to bubble sputter-spit when they drive.

Pinus contorta 'Willow Creek'

Pinus contorta var. latifolia 'Willow Creek' is a dwarf, compact upright Lodgepole pine that was discovered in Colorado's Rocky Mountains. Needles are long and dark green and they set off the orange-brown candles nicely, especially in winter. We only have one tree available for scionwood, and it's small and located at Flora Farm, so the 20 we grafted will become future stock trees as they mature (requiring a 4-5 year investment). Ultimately we hope to produce a couple of hundred per year. Hardy to -30 F, USDA zone 4.

Pinus contorta 'Taylor's Sunburst'

Pinus contorta 'Taylor's Sunburst'

Pinus contorta var. latifolia 'Taylor's Sunburst' was also discovered in the Colorado Rockies in the mid 1980s. The original tree was found by Dr. Allan Taylor at about 9000 ft. altitude, and supposedly the upper half of the 35 ft. tree was creamy yellow even in September. At Buchholz Nursery we grow it in full sun where the new shoots are brilliantly colored which contrasts with older, green foliage. 'Taylor's Sunburst' is particularly attractive when sized about 3' to 8' tall; once it gets older it can appear a bit scrappy, especially since it is a boring green tree for 10 months out of the year. My advice is to grow it at the bottom of a hill so you can look down on it rather than up at it. I coach Jordan to carefully cut off any cones growing on the scion...without damaging the terminal buds. He wondered if the grafting shoots that I pointed out were a little too large for our rootstock, but I likened them to a fluffy-coated dog, that when wet he doesn't look so big after all; when the lower needles of the pine scion are removed, suddenly the stick caliper appears more acceptable. Also, stay away from the skimpy lower shoots with wimpy buds. Those lower scions might “take” if one is desperate for numbers, but the vigorous scions save a year or two on producing a salable, vigorous tree.

Pinus contorta 'Chief Joseph'

Pinus contorta 'Chief Joseph'

We “finished” our Pinus contorta var. latifolia rootstock with the hard-to-find 'Chief Joseph'. Hard to find, but easy to sell for a good price. Most propagators find the 'Chief' difficult, where 20-30% takes are common; others use various strategies to increase performance. One grower keeps all his stock trees inside a shaded greenhouse where the scions will be more green. Another grower grafts his from outside stock, but does so in October before the tree goes vibrantly gold. Last year I was happy with a 65% take, although my grafter (David) wondered why he got 90% take on 'Taylor's Sunburst', 'Willow Creek' and 'Frisian Gold', but did so poor on 'Chief Joseph'. He doesn't remember that we've never achieved a 90% on the Chief; and no, you won't lose your job because of it. Actually I love it when employees worry about results because it shows that they take the outcome seriously. I prefer to have company when I worry, and after all, we all want to make more money. We leave the green rootstocks attached to 'Chief Joseph' for at least a year or two, as the green understock will develop faster root growth than the purely yellow scion when potted up. Two additional years – after the graft year – are required to make a salable one-gallon pot, and I wished I had a couple thousand for sale each year, not our normal couple of hundred.

Ok, now we have finished all P. contorta rootstock. Right? Make sure that nothing is left before we bring in the Pinus sylvestris. Yes, we have mixed them up in the past, so focus is required from all who are involved in the propagation process. No one gets fired when he or she makes mistakes, no one receives a pay deduction for their errors...except for Old Buchholz.

Pinus mugo 'Carsten's Wintergold'

Pinus mugo 'Carsten's Wintergold'

Every flat of grafts that we complete is identified with two stick labels, one on each front corner. Unfortunately there are only about ten label colors, so there are many pinus cultivars – maybe a dozen – with the same label color. When the flats are moved from the prop building into the greenhouse I never want to see two similar Pinus cultivars next to each other. It's too easy for the crew to space out on the exact names, especially when they are potted up or sold later in the year. For example Pinus mugo 'Carsten's Wintergold' should not be placed next to Pinus mugo 'Ophir'. Put a green cultivar, or a variegated one in between the two golden selections. I'm fussy about those details, but for good reason. 'Carsten's Wintergold' is a dense mounding shrub with green needles in spring and summer, then in late autumn and throughout winter they turn to a rich golden-yellow. In ten years our plants are about 3 ft. tall by 4 ft. wide, and the winter color is best when planted in full sun. Also known as 'Carsten', it was discovered and introduced by Erwin Carsten of Varel, Germany in the 1980s.

Pinus mugo 'Ophir'

Solomon

Remember now, don't put the Pinus mugo 'Ophir' next to the 'Carstens'. Why do I have to always remind the crew? 'Ophir' is not quite as intense a golden winter color, but it displays a wonderful glow in the winterscape, so I actually prefer it over 'Carstens'. In any case both cultivars received the prestigious Award of Garden Merit (AGM) of the Royal Horticultural Society. 'Ophir' was selected in Holland, and at Buchholz Nursery it grows a little more dwarf than 'Carstens'. Both cultivars are problem free for us, and when we hit 116F in late June a couple of years ago the needles had already changed to green and didn't burn at all. “Ophir” is a name mentioned in the Bible, a port (probably) famous for its wealth, i.e. gold. King Solomon led an expedition to Ophir and brought back large amounts of gold, and other books in the Hebrew Bible also describe “the gold of Ophir.” The exact location of Ophir is unknown, but it was probably a port on the Red Sea. Old Solomon was fortunate to have made his gold haul when he did; if today, his ship would probably be attacked by pirates and missiles.

Pinus sylvestris 'Gold Coin'

Likewise, don't mix up the similar Pinus sylvestris 'Gold Coin' with Pinus sylvestris 'Nisbet's Gold'. 'Gold Coin' is slightly more brilliant for golden winter color, but then it can burn when newly planted in full sun (in Oregon). It should be grown in full sun for best color though, and will burn less and less for each season as it becomes established. 'Gold Coin' is not a dwarf (at all) though it starts out slow. Eventually it can put out 2-3 ft. of growth annually, so my recommendation is to candle-prune in May (at least in our lush nursery). The leader candle is cut in half and the side shoots about 2/3 to keep the tree compact. According to to the RHS Encyclopedia of Conifers, 'Gold Coin' “originated before 1979 by R.S. Corley, UK.”

Pinus sylvestris 'Nisbet's Gold'

Pinus sylvestris 'Nisbet's Gold' is similar to P.s. 'Gold Coin', but the former's origin is uncertain...and the RHS simply mentions that it was “recorded from the USA and growing in the Arboretum Trompenburg before 2008.” 'Nisbet's Gold' should not be confused with 'Nisbet's Gem' as they are very different. The RHS implies that the Nisbet clones are from the A.H. Nisbet Collection, Gosport, Hampshire, UK, even though claiming previously that the origin is unknown. I've been growing both 'Gold Coin' and 'Nisbet's Gold' for about 30 years, but probably the new Buchholz Nursery owners (MrMaple) should grow just one cultivar, whichever garners the most sales.

Pinus densiflora

Pinus densiflora

South Korean Flag

Pinus densiflora is variously described as the “Japanese Red pine,” but it's also known in Korea as the “Korean Red pine.” The specific epithet densiflora simply means “densely-flowered” due to the many small cones that are produced on a mature tree. The species is native to Korea, Japan, China and Siberia, but it's the Koreans with their national zeal that assume “ownership.” It is known as sonamu, or “Supreme tree,” and is honored in their national anthem:

As the tree atop Namsan* stands firm
unchanged through wind and frost,
as if wrapped in armour,
so shall our resilient spirit.

*Namsan is a hill in the center of Seoul.

Pinus densiflora 'Pope'

We grafted two cultivars of Pinus densiflora last week: 'Golden Ghost' and 'Pope', and both are known for variegated needles in the “Dragon's Eye” fashion. I don't know much about the origin of 'Pope', which we have grafted off-and-on for a dozen years, but it looks particularly attractive this winter. My Master Plant List (MPL), the bible of all our species and cultivars, simply indicates that my source is “Pope,” but I can't remember now who or where or what “Pope” is. I doubt that the selection originated at the Vatican.

Pinus densiflora 'Golden Ghost'

Pinus densiflora 'Golden Ghost'

Pinus densiflora 'Golden Ghost' is also a variegated form of the “Red pine” but its needles feature cream-yellow markings versus the golden-orange foliage of 'Pope'. Both selections are propagated using Pinus sylvestris rootstock, but the vibrancy of the variegation can vary depending upon cultural and geographical factors. I have seen stunning specimens of 'Golden Ghost' on the East Coast, USA that far outshine the color we get in Oregon. As is often the case, the colder the climate the better the variegation, and also more lean soils provide for improved appearance. I remember an impressive 'Golden Ghost' specimen at the now defunct Mitsch nursery of Oregon, and the former owner (John Mitsch) attributed the spectacular variegation to the fact that he seldom irrigated the area where it was growing. My start came from the late Bill Devine (1927-2022); I never met the man but we traded scionwood about 25 years ago, and he was also noted for Cedrus deodara 'Devinely Blue', Pinus densiflora 'Glitzer Pendula', Pinus mugo 'Elmwood', Pinus parviflora 'Bonny' and other conifers, not that he necessarily introduced all of them.

Pinus thunbergii 'Ogon'

We grafted Pinus thunbergii 'Ogon' and 'War Bonnet' on Pinus sylvestris, and these two cultivars also needed separation in the greenhouse due to similarity. Ogon means gold in Japanese, but the characters refer to a “yellow-gold,” whereas kin means a solid gold. My oldest stock tree of 'Ogon' is growing in full sun at Flora Farm and it is approximately 8' tall by 10' wide in 20 years. The needles burned on the south side when we reached 108 F last summer – even with plenty of irrigation – so I cut the scions from the north and east portions that had no scorch. I consider 'Ogon' to be a vigorous dwarf, but one difficulty in grafting is that the scion shoots are often very thick. A lot of times you can't use the leader in the new-growth whorl, rather you must use one of the side shoots...and that might account for its bushy, sprawling form.

Pinus thunbergii 'War Bonnet'

Also quite vigorous is Pinus thunbergii 'War Bonnet', and the propagator faces the same challenges as with 'Ogon'. To produce full, colorful trees – especially in containers – one should candle prune to prevent a leggy form. I don't know the source of the 'War Bonnet' introduction or how it received its name. I do remember, though, that scions originally came to me as densiflora for the specific epithet, which it clearly is not. I'm sure I sold a few grafts or other small sizes before I was set straight by a customer...so sorry about that.

Pinus monophylla

Fascicle Example

We've grafted other cultivars of two-needle pines which I won't discuss in this blog. But first, let's make sure the reader knows what I mean by “two-needle.” We have grown one-needle, two-needle, three-needle and finally, five needle pines, and the needle count refers to how many needles (leaves) occupy a single fascicle on the scion shoot. The term fascicle is derived from Latin fascis which means “bundle.” An example of a one-leaved pine is Pinus monophylla, a two-leaved pine are all the cultivars mentioned in this blog, a three-leaved pine is Pinus bungeana, and a five-leaved pine is Pinus strobus. Some pines try to confound you when the number of needles can vary; but anyway, if you stick to the general outline, a scion with a certain number of needles per bundle will suggest to the propagator an appropriate rootstock to use.