松の「もみあげ」とは──古い葉を手でむしる冬の手入れ|樹木医が解説(Momiage: Needle Plucking on Japanese Pines)

English: Momiage — Needle Plucking on Japanese Pines in Autumn and Winter

Momiage (もみあげ) is the Japanese gardener’s practice of plucking the old needles from pines by hand in autumn and winter, so that light and air reach the lower branches. In this article, a Jumokui (tree doctor) explains why pines alone are never sheared but have their needles pulled, how many needles to leave and when, and the harm of overdoing it, drawing on Japanese forestry and garden sources and on research from abroad.

This is the second article in our series on the pruning techniques of Japanese gardeners (niwashi and uekiya). After sukashi (thinning) in the first article, we turn with the season to the winter care of pines that is about to begin: momiage.

What momiage is: plucking the old needles of a pine by hand

As autumn deepens, bundles of brown pine needles lie beneath the pines of gardens and temples. A gardener has climbed the tree and is plucking the old needles with their fingers. This is momiage. Written 揉み上げ, it is also called ha-mushiri (needle plucking) or furuba-tori (old-needle removal).

The Nagano Prefectural Forestry Research Center’s technical note “Pruning Pines” (1999) explains it this way: to keep a pine’s form beautiful and to prevent pests and diseases, sunlight must reach the lower branches; so in autumn, last year’s old needles and part of this year’s are plucked lightly by hand. The special specification for the Ministry of the Environment’s maintenance contract covering 139 Japanese black pines (Pinus thunbergii) in the Kokyo Gaien National Garden (fiscal 2023) likewise calls for “momiage of old needles”. The National Gardens Association, which manages the Kyoto Gyoen National Garden, presents it as the December “New Year preparation” of the pines, removing old needles so that sunlight reaches the lower branches. In Japanese garden pine care, this work is built in as a matter of course.

The distinction between needles to keep and needles to pluck is clear. The needles that grew this year, at the shoot tips (current-year needles), are kept; the previous years’ needles further back along the shoot (old needles) are plucked.

Why pines alone are not sheared, but have their needles pulled

Other garden trees are sheared with hedge shears or cut back partway along their branches. There are reasons in the pine’s own biology why this is not done to pines.

The first is needle longevity. Pine needles are evergreen, but they do not stay on the tree for many years. A report from the Kyoto University Forests, “Needle longevity in the genus Pinus” (1992), surveyed the number of years needles were retained on 60 pine species and found an average of 2.27 years. In the same report, Japanese black pine retained needles for about 2.6 years and Japanese red pine (Pinus densiflora) for about 1.6 years. In other words, the old needles removed in momiage are needles that would turn brown and fall anyway. The gardener drops them first, by hand, before they turn brown.

The second is where the buds are. Pines form buds only at the shoot tips and grow in a single flush each year. The Nagano note says that pines form next year’s buds by summer, so pinching those buds after mid-August means no new shoots the following spring, and that shearing the foliage in autumn removes much of the current year’s needles and starts a decline in vigor.

If you shear the foliage, you cut through the current-year needles you wanted to keep and lose the source of next year’s buds. That is why, on pines, shears are used only to cut branches, and the needles are removed by hand. The Nagano note states flatly that shaping a pine by hacking at it with large shears is the single greatest cause of pines losing vigor. From our experience in the field, pine needles cut with shears turn brown from the cut end.

Bringing light to the lower branches: the purpose of momiage

The first purpose of momiage is light. The USDA Forest Service guide “How to Prune Trees” states that branches which cannot produce enough carbohydrates through photosynthesis to sustain themselves die and are shed. Pines are especially intolerant of shade, and lower and inner branches that receive no light die back.

A pine pad (the cushion of foliage on a tiered branch) with several years of old needles piled up is dark inside, and the inner twigs are losing their needles. Plucking the old needles thins the layer of foliage, and light reaches the inside of the pad. From our experience in the field, on pines where momiage is kept up, the small inner twigs survive with their buds intact, the branches do not become leggy, and the pads hold their shape for many years.

The second purpose is air flow and pest and disease control; the Nagano note says light reaching the lower branches is needed to prevent pests and diseases. The third is appearance. The garden newsletter of Murin-an in Kyoto writes that by the end of November the old needles from the previous spring have faded, that they turn brown over the winter and look unsightly, and that all of them are therefore plucked by hand before they turn brown.

Timing: autumn to year’s end, then candle pinching in spring

The season is autumn to winter. A survey by Minoru Maeda (1966) states that autumn needle plucking and pruning are done from September to December; Murin-an cites late November and Kyoto Gyoen December. The Kokyo Gaien maintenance contract runs until February or March of the following year. In our own work, momiage is done from November into the New Year, and on the “Garyu no Matsu” (the Reclining Dragon Pine) at Jushoin temple in Edogawa, Tokyo, we carry out momiage of the old needles every year as the year-end care.

Pine care comes as a pair of operations each year. The Nagano note presents two methods peculiar to pines: “midori-tsumi” (candle pinching), in which part of the new shoot or “midori” that emerges around May is pinched off with the fingers to regulate the amount of foliage, and autumn “ha-mushiri (momiage)”. Maeda’s survey also describes spring candle pinching (May to July) and autumn needle plucking and pruning (September to December) as the basis. Restrain the growth in spring, drop the old needles in winter: through this back-and-forth, the pine renews its needles without changing size. Midori-tsumi will be covered in a spring article.

How it is done: top to bottom, thin first, then pluck

Maeda’s survey states that the crowded parts of the branches are first thinned by pruning, and then all the old needles among those remaining are plucked off by hand. Murin-an writes that the work begins at the top of the tree and moves gradually down to the lower branches, because the plucked needles fall onto the pads below.

The branches removed in the preliminary thinning overlap with the imi-eda (branches to be avoided) described in the first article. The Kokyo Gaien specification lists “dead branches, upright branches, crossing branches, overlapping branches and the like”; Kyoto Gyoen describes dealing with overcrowded branches, dead branches, and branches growing upward or hanging downward. The red marks in the illustration show the cutting points, just outside the fork with the parent branch.

Once the branches are in order, the needles are plucked. In our own work, we pinch a few old needles at a time between thumb and forefinger and pull them in the direction the needles grow, that is, from the base of the shoot toward its tip. Pull against that direction and you may strip the bark with them or damage the needles you want to keep and the bud at the tip.

How many to leave? In Maeda’s survey, the guideline for the hard plucking done at ordinary private houses was 15 to 16 needles per bud (7 to 8 pairs, since the needles come in twos); at the Kyoto Imperial Palace and the Shugakuin Imperial Villa, black pines were deliberately left with more, an average of 24 to 25 needles per bud after plucking.

The amount left is not uniform over the tree. In our own work, the vigorous upper tiers are left with fewer needles, and the weaker lower tiers and inner branches with more. A National Bonsai Foundation article (2020) on the care of a Japanese black pine at the U.S. National Bonsai & Penjing Museum says the same: more needles are pulled in stronger areas and fewer in weaker spots to balance the growth.

The work is done from a Japanese tripod ladder, with both hands in the top of the pad, finishing one pad before moving to the next. On tall pines or pines with wide-spreading branches, we climb the tree on ropes and follow the same sequence (see our article on caring for trained pines).

When a shoot is finished, only the current-year needle cluster remains at the tip of each twig, and the way the branches divide becomes visible.

What only the hands can tell: the craftsman’s sense, and pines for the New Year

There is no machine for momiage. Thousands of needles are plucked by the fingers for a single pine. Among gardeners, this labor has long been regarded as the substance of pine care itself. Touch tells you the vigor of a branch through the stiffness of its needles and the tension of the shoot: a vigorous branch has firm, tightly set needles, a weak one has thin needles that feel slight between the fingers. Through that feel, which never comes through a pair of shears, the number of needles left is varied branch by branch. Japanese black pine needles are sharp-pointed; the Kyoto Gyoen article notes that they hurt and cannot be removed easily, so the work takes time. Even with gloves the fingertips ache, and with that ache the gardener comes to know the tree.

The aesthetic of the finished work is distinctive too. Gosho-sukashi, the thinning style of the Kyoto Imperial Palace, is described in the multilingual guide of Japan’s Ministry of Land, Infrastructure, Transport and Tourism as demanding such care that one notices the tree has been worked on only by seeing the cut branches and needles lying at its foot. Pruned without looking pruned, plucked without looking plucked: spending effort to erase the traces of one’s own work is the sensibility of the Japanese gardener.

And pine care is bound to the calendar. Kyoto Gyoen calls its December momiage the pines’ “New Year preparation,” and Murin-an carries out the work from autumn as preparation for the coming year. Greeting the New Year with pines that stand green and trim marks the turn of the year for the garden’s owner and for the gardener alike. This handwork is learned by watching the master’s hands and through one’s own cold fingertips. In our company too, young gardeners join the year-end momiage of the Garyu no Matsu under the guidance of experienced Jumokui and senior craftsmen.

The harm of overdoing it, and the form that only yearly repetition can produce: for readers abroad

Momiage is work that reduces foliage, so overdoing it weakens the pine. Maeda estimated the proportion of needles lost each year to candle pinching and needle plucking on the pines of the Imperial Palace and Shugakuin, put it at 85 percent or more, and wrote that the method generally practiced had already reached its limit from the standpoint of growth.

The Nagano note asks that on pines whose vigor is declining, candle pinching be skipped for that year. The same applies to momiage. In our own work, on pines losing needles to needle-cast diseases, pines recently transplanted, and pines that received hard treatment the previous year, we leave more of the old needles. As we noted in our Jumokui diagnosis of a Japanese red pine, excessive pruning or momiage on an infected pine risks a decline in vigor. Look at the condition of the tree before working on it. This is the premise of all pruning, not only of pines.

The Kokyo Gaien specification calls for shaping the pines so that the number of buds increases year by year and the branches fill out. Momiage does not make a form in a single session; repeated every year, it keeps a pine with thin, well-ordered pads and needles down to the lowest branches. A pine left untended for years develops swollen pads that merge together, its interior and lower branches die back, and it cannot be returned to its former shape.

In arboriculture abroad, pine care is more often discussed as pinching the spring candles by hand. Work close to Japanese momiage is called needle plucking in the English-speaking world, in the context of bonsai and Japanese gardens.

The pine’s mechanics, its needle longevity and the position of its buds, are the same in any country. Reading those mechanics, and renewing a year’s needles with the fingers rather than with shears: one pillar of GREEN MANAGEMENT, the approach of our company, is the integration of scientific knowledge (arboriculture) and field experience, and I believe it applies directly to the winter care of pines.

Frequently asked questions

Q1. What is momiage on pines?

A. It is the practice of plucking by hand, in autumn and winter, the previous years’ old needles from the base of pine shoots while keeping the current-year needles at the tips. It is also called ha-mushiri (needle plucking) or furuba-tori. The Nagano Prefectural Forestry Research Center describes it as work to let sunlight reach the lower branches, keep the form, and prevent pests and diseases, improving air flow and light.

Q2. When is momiage done?

A. Mainly from autumn to the end of the year. Minoru Maeda’s 1966 survey cites September to December, Murin-an in Kyoto late November, and Kyoto Gyoen December; the Kokyo Gaien maintenance contract runs to February or March. In our own work it is done from November into the New Year.

Q3. How many needles should be left?

A. The basic rule is to keep the current-year needles at the tips and pluck the previous years’ needles. In Maeda’s survey, 15 to 16 needles per bud were left in hard plucking at ordinary houses, and an average of 24 to 25 on the black pines of the Kyoto Imperial Palace and Shugakuin. Vigorous branches are left with fewer and weak branches with more.

Q4. Why must pine needles not be cut with shears?

A. Shears are used only to cut branches; needles are removed by hand. Pines form buds only at the shoot tips and set next year’s buds by summer, so shearing the foliage removes the current-year needles and next year’s buds and weakens the tree. The Nagano note calls shearing with large shears the greatest cause of pines losing vigor. Needles cut with shears turn brown from the cut.

Q5. What happens if momiage is not done?

A. Old needles pile up, the inside of the pad becomes dark, and the inner twigs and lower branches that receive no light die back, because pines love sun and branches that cannot sustain themselves by photosynthesis die and are shed. A pine untended for years develops swollen, merged pads and is hard to return to its former shape. The old needles turn brown and fall in winter in any case.

Sources

– Nagano Prefectural Forestry Research Center. Mini Technical Note No. 11, “Pruning Pines”. May 1999.
– Ministry of the Environment, Kokyo Gaien National Garden Office. Special Specification, Fiscal 2023 Kokyo Gaien Pine Maintenance Works (139 Japanese black pines).
– National Gardens Association, Kyoto Gyoen. “Pine momiage and pruning: toward the year’s end.” 19 December 2018.
– Murin-an (Kyoto). Garden newsletter “Sarasara”, October–November 2019, “The gardener’s eye”.
– Maeda, M. “On the training and pruning of pine trees.” Journal of the Japanese Institute of Landscape Architects 29(4): 2–5, 1966. doi:10.5632/jila1934.29.4_2
– Oshima, S. “Needle longevity in the genus Pinus.” Bulletin of the Kyoto University Forests 64, 1992.
– Tokyo Metropolitan Government, Bureau of Construction. Standard Specification for Street Tree Maintenance (Green Space Management). April 2013.
– Virginia Cooperative Extension. A Guide to Successful Pruning, Pruning Evergreen Trees. Publication 430-457, 2022.
– University of Wisconsin–Madison Extension. Pruning Evergreens. Revised 2012.
– Bedker, P.J., O’Brien, J.G., Mielke, M.E. How to Prune Trees. USDA Forest Service, NA-FR-01-95, 1995 (revised 2012).
– National Bonsai Foundation. “Historical Tree Spotlight: A Black Pine from Dr. Yee-sun Wu.” 18 December 2020.
– Japan Tourism Agency, MLIT. Multilingual commentary database: “Tools for Gosho-sukashi, Kan’in-no-miya Residence Site Exhibition Hall.”

Masatoshi Nakamura
Jumokui (Tree Doctor), Toshi Landscape Co., Ltd., Tokyo